Sensor having a primary coil, two secondary coils as well as an evaluator. An excitation signal may be applied to the primary coil. An output signal depending on a position of a coupling element may be induced in each secondary coil. An evaluator is configured to evaluate the output signals in order to evaluate a phase offset between the output signals. Further, the evaluator is configured to provide a sensor output signal indicating the position or change in position of the coupling element.

The functional principle of inductive sensors operating in accordance with the linear variable differential transformer (LVDT) principle is based on coupling between a primary coil and two secondary coils by means of a coupling element. Shifting the coupling element has an influence on the voltages induced in the secondary coils so that drawing conclusions as to the position of the coupling element is possible using the voltages at the secondary coils.
The primary coil here is driven by an excitation signal or primary signal having an excitation frequency. The signal induced may be tapped at both secondary coils. With a symmetrical arrangement of the primary and secondary coils, the secondary signal induced by the primary signal in both secondary coils may be of equal quantity, when there is no coupling element. When there is a coupling element, there is a position thereof where coupling between the primary coil and the two secondary coils is equal such that the two secondary signals are also equal. When shifting the coupling element from said position, the secondary signals change reversely to each other such that a difference signal, which is dependent on the shift, may be achieved. Using so-called amplitude modulation methods, such as, for example, full-wave rectification, separate full-wave rectification including difference formation or synchronous demodulation, the difference signal may be evaluated.
With full-wave rectification, as may exemplarily take place in LVDT positional sensors by the ASM Automation Sensorik Messtechnik GmbH company, the two secondary coils are connected in phase opposition. The demodulated output signal may exhibit a typical V-shape, as is exemplarily illustrated in FIG. 18a. With a shifted coupling element, an amplitude in the output voltage may hint at two positions different from each other. In other words, full-wave rectification induces a problem of lacking unambiguity of the measuring signal. Without further auxiliary measures or further evaluations, it may be impossible to recognize whether the coupling element is on one or the other side of the zero position. Furthermore, the demodulated output signal is originally non-linear and may exhibit an offset which may result in the sensor signal also to comprise a value un-equaling zero in the symmetry position of the coupling element. In accordance with literature, the reason for this is, among other things, flow losses in the LVDT.
A separate full-wave rectification may exemplarily be performed in order to make the measuring signal unambiguous, wherein at first each of the secondary signals is demodulated separately and subsequently a difference is calculated such that the result is an unambiguous characteristic curve, as is exemplarily illustrated in FIG. 18b. Alternatively, full-wave rectification may be combined with phase detection such that a case-by-case analysis for the left and right branches of the V-shaped sensor signal curve is possible, as is exemplarily illustrated in FIG. 18c.
Both full-wave rectification and separate full-wave rectification and synchronous demodulation, as may exemplarily be performed in accordance with the application document SPRA 946 by the Texas Instruments company, result in additional circuit complexity which may necessitate expensive electronics.
Evaluating the signal amplitudes may also take place using a route mean square-to-direct current (RMS-to-DC) conversion, as is exemplarily described in the Design Note 362 by the Linear Technology company.
Integrated devices which combine several of these functions are, for example, the devices AD598 or AD698 by the Analog Devices company.
When evaluating the sensor signals, digitalization of the signals at the secondary coils may exemplarily be performed by an analog-to-digital converter (ADC).
The amplitude response of LVDT sensors may exhibit strong distortions when there are external magnetic fields or ferromagnetic material, as is exemplarily illustrated in FIGS. 21a to 21d. The result is that sensors operating in accordance with the LVDT principle may be unsuitable in many measuring arrangements where, for example, the sensor is to be accommodated in a metal casing or where there are strong magnetic fields, such as, for example, in electric motors.
Consequently, a device and a method for being able to measure a position of an element unambiguously and independently of external magnetic fields would be desirable.
The object underlying the present invention is providing sensors and methods for operating same which exhibit reduced space requirements and provide a more robust and more reliable detection of positions of movable objects.

Sensor for indicating a position or a change in position of a coupling element and method for operating the sensor

Hahn-Schickard-Gesellschaft für angewandte Forschung e.V.


A method is for making an electrical inductor. The method includes forming a first subunit having a sacrificial substrate, and an electrically conductive layer defining the electrical inductor and including a first metal on the sacrificial substrate. The method includes forming a second subunit having a dielectric layer and an electrically conductive layer thereon defining electrical inductor terminals and having the first metal, and coating a second metal onto the first metal of one of the first and second subunits. The method includes aligning the first and second subunits together, heating and pressing the aligned first and second subunits to form an intermetallic compound of the first and second metals bonding adjacent metal portions together, and removing the sacrificial substrate.

An electronic device may include one or more circuit boards. A typical circuit board is a planar board that mechanically supports electronic components. The electronic components may comprise, for example, resistors, capacitors, switches, batteries, and other more complex integrated circuit components, i.e. microprocessors. The circuit board typically comprises a dielectric material, for example, a plastic material.
The circuit board may include conductive traces on the surface for connecting the electronic components to each other. As electronic circuitry has become more complex, multilayer circuit boards with at least two electrically conductive pattern layers have been developed. Typically, the different conductive trace layers of a multilayer circuit board may be connected through vertically extending vias, which comprise conductive materials, for example, metal.
A typical multilayer circuit board may comprise a plurality of core layers with bonding layers therebetween affixing the adjacent core layers together. Each core layer typically includes a dielectric layer with electrically conductive pattern layers on the opposing major surfaces of the dielectric layer. Typically, during manufacture of the multilayer circuit boards, the core and bonding layers are stacked together and then heated (laminated) to cause the bonding layer to affix the adjacent core layers together.
For example, one device application for the multilayer circuit board comprises an electrical inductor. The device is typically formed with spiral inductive elements on a major surface of the multilayer circuit board. Of course, an increase in the number of spiral inductive elements results in a commensurate rise in the generated inductance. Accordingly, there is a desire to decrease the spiral spacing between elements to generate more inductance while consuming less real estate of the multilayer circuit board.
In some applications, polymers may be used as the substrate for the spiral inductive elements. They may provide for several desirable characteristics, such as less loss. Nevertheless, the manufacturing techniques for these polymers may place a minimum on the spacing of the spiral inductive elements, for example, spiral spacing greater than or equal to 50 μm. Additionally, these polymer approaches may suffer from reduced operational bandwidth and may become self-resonant at low frequencies, i.e. making the inductor unusable.
An approach to this problem is to manufacture the spiral inductive elements on a semiconductor substrate, such as silicon or glass, where manufacturing precision is greater and allows for reduced spiral spacing. Notwithstanding the greater manufacturing resolution of building the electrical inductor on semiconductor material, these approaches may suffer from less operating bandwidth and greater loss due to the electrical characteristics of semiconductor material. Also, the semiconductor approaches may also experience self-resonance as the number of spiral inductive elements increases due to the loading effects of the semiconductor. Another drawback may include the need to insert a thick insulating layer between the semiconductor layer and the spiraled inductive elements to prevent a DC shorting of the spiral inductive elements, which adds to cost and board size.
For example, one approach is disclosed in U.S. Pat. No. 7,551,052 to Jow et al. The electrical inductor includes a high permeability magnetic substrate, conductive traces formed on the substrate to form circular inductive spirals, and a via passing through the substrate and coupling the conductive traces with additional traces on the backside of the substrate.
U.S. Pat. No. 7,345,563 to Pavier discloses a multi-layer circuit board comprising a laminate layer, a conductive layer thereon, and a magnetic layer also on the laminate layer. The multi-layer circuit board also includes a plurality of spiral inductive elements on the magnetic layer.

Method for making an electrical inductor and related inductor devices


One or more important sentence structural functional units are extracted from an important portion of each of a plurality of documents, and one or more input sentence structural functional units are extracted from an input sentence. Each of the functional units is a noun phrase, a verb phrase, a pair of nouns connected each other through a preposition or the like. The important sentence structural functional units of each document are collated with the input sentence structural functional units to detect a matching degree, and a similarity level is determined from the matching degree for each document. Thereafter, occurrence frequencies of retrieval words existing in each documents are collated with occurrence frequencies of query words existing in the input sentence to determine an estimation value according to an estimation function for each document, the documents are ranked on condition that one or more documents of a high similarity level are ranked to a higher rank than one or more documents of a low similarity level and a plurality of documents of the same similarity level are ranked in the order of decreasing their estimation values. Accordingly, because the similarity level is determined for each document by considering the functional units, a user can retrieve one or more necessary documents with a high accuracy.

1. Field of the Invention
The present invention relates generally to a document retrieval system in which a desired document is retrieved from a data base in which pieces of electronic document information are stored, and more particularly to a document retrieval system in which a desired document is efficiently retrieved with high accuracy from a storing unit such as a document information data base, a general word processor or an office computer.
2. Description of the Related Art
A large number of pieces of electronic document information such as electronic mails, electronic catalogs, electronic publications and the like have been recently circulated, so that a document retrieval system in which a desired document is retrieved from a document information data base has been required.
In a conventional document retrieval system, a keyword search method for using a keyword manually attached to each of documents or a full-text search method for performing the collation of a plurality of character strings in a whole document with a reference character string with a high speed is generally used. In the full-text search method, any keyword attaching work manually performed is not required.
However, any of the above conventional methods is performed according to an exact match retrieval model in which the perfect agreement of query (or reference) information with superficial information such as a word, a character string or the like is required. That is, a user is required to prepare a retrieval formula (normally denoting a logical formula including a logical symbol "AND", "OR", "NOT" or the like) composed of a query character string as the query information. Therefore, unless the user is an expert for a document retrieval, it is difficult for the user to prepare an appropriate retrieval formula matching with a retrieval intention of the user. As a result, there is a case that all desired documents are not retrieved or a large number of unnecessary documents are undesirably retrieved, so that there is a drawback that a retrieval accuracy and a retrieval efficiency deteriorate together.
To avoid the above drawback, a large number of document retrieval methods according to an inexact match retrieval model have been proposed. In the inexact match retrieval model, a user specifies a natural language sentence or a typical sentence expressing a user's retrieval intention, so that the user is not required to prepare a logical formula. As a representative example of the inexact match retrieval model, a vector space model is well-known. In the vector space model, each of a plurality of documents and a query sentence is respectively expressed by a multi-dimensional characteristic vector, the similarity between the query sentence and each of the documents is measured by calculating a distance between the vector of the query sentence and the vector of a corresponding document, and the documents are ranked in order of similarity. A technique represented by the vector space model is disclosed in a literature "Salton, G. and McGill, M. J. :Introduction to Modern Information Retrieval, McGraw-Hill Publishing Company, 1983".
2.1. Previously Proposed Art
A document retrieval processing according to the conventional vector space model is described with reference to drawings.
FIG. 1 is a block diagram of a conventional document retrieval system operated according to the conventional vector space model. As shown in FIG. 1, a conventional document retrieval system 100 is composed of
a document storing unit 101 for storing a plurality of documents planned to be retrieved, PA1 a word occurrence frequency calculating unit 102 for reading out the documents from the document storing unit 101 and calculating an occurrence frequency of each of a plurality of words used in each of the documents, p1 a word occurrence frequency information storing unit 103 for storing the words and the occurrence frequencies calculated in the word occurrence frequency calculating unit 102 for each of the documents as word occurrence frequency information, PA1 an input and output unit 104 for receiving an input sentence from a user and outputting ranks of the documents to the user, PA1 an input sentence analyzing unit 105 for analyzing the input sentence received by the input and output unit 104 to extract a plurality of words from the input sentence as a plurality of query words used for retrieval and calculate an occurrence frequency of each of the query words and a weighting factor for each of the query words, PA1 an input word information storing unit 106 for temporarily storing the query words, the occurrence frequencies and the weighting factors obtained in the input sentence analyzing unit 105 as input word information, and PA1 a document rank calculating unit 107 for comparing and collating the word occurrence frequency information stored in the word occurrence frequency information storing unit 103 with the input word information stored in the input word information storing unit 106 to rank the documents in order of similarity to the input sentence and outputting a retrieval result indicating the ranks of the documents to the input and output unit 104. PA1 S1=.SIGMA. (weighting factor for one query word * occurrence frequency of one retrieval word agreeing with the query word)=1*2 (athletic)+1*3 (meeting)+1*1 (hold)=6 PA1 S=1*1 (athletic)+1*1 (meeting)+1*1 (hold)=3 PA1 S3=.SIGMA. (weighting factor for one query word * occurrence frequency of a corresponding retrieval word)=1*3 (athletic)+1*2 (meeting)+1*2 (hold)=7 PA1 word occurrence frequency calculating means for calculating an occurrence frequency of each of a plurality of retrieval words existing in each of a plurality of documents; PA1 functional unit extracting means for extracting one or more document sentence structural functional units from each of the documents; PA1 input sentence analyzing means for calculating an occurrence frequency of each of a plurality of query words existing in an input sentence and extracting one or more input sentence structural functional units from the input sentence; PA1 functional unit collating means for collating the document sentence structural functional units of each document extracted by the functional unit extracting means with the input sentence structural functional units extracted by the input sentence analyzing means to calculate a matching degree of each document with the input sentence and classifying the documents into a plurality of similarity levels according to the matching degrees of the documents; and PA1 document rank determining means for calculating an estimation value of each of the documents from the occurrence frequencies of the retrieval words of the corresponding document calculated by the word occurrence frequency calculating means and the occurrence frequencies of the query words of the input sentence calculated by the input sentence analyzing means according to an estimation function and ranking each of the documents on condition that one or more documents classified into a high similarity level by the functional unit collating means are ranked to a higher level than one or more documents classified into a low similarity level by the functional unit collating means and a plurality of documents classified into the same similarity level are ranked in the order of decreasing their estimation values; and PA1 outputting means for outputting a document retrieval result indicating the ranks of the documents. PA1 important portion extracting means for extracting an important portion expressing a theme of one document from each of the documents; and PA1 important functional unit extracting means for extracting one or more important sentence structural functional units from each of the important portions of the documents extracted by the important portion extracting means as the document sentence structural functional units. PA1 retrieval formula generating means for generating a retrieval formula expressed by a logical combination of the query words of the input sentence; and PA1 retrieval document selecting means for examining whether or not each of the documents satisfies the retrieval formula generated by the retrieval formula generating means by searching the whole documents and selecting one or more particular documents satisfying the retrieval formula from the documents, particular document sentence structural functional units of each particular document selected from the document sentence structural functional units of each document being collated with the input sentence structural functional units by the functional unit collating means.
In the above configuration, before a document retrieval is performed by a user, the documents stored in the document storing unit 101 are read out to the word occurrence frequency calculating unit 102, a morphological analysis is performed for each of the documents if necessary, each of the documents is divided into a plurality of retrieval words, an occurrence frequency of each of the retrieval words is measured for each of the documents, and the retrieval words and the occurrence frequencies are stored in the word occurrence frequency information storing unit 103 as word occurrence frequency information.
An example of a document planned to be retrieved is shown in FIG. 2.
As shown in FIG. 2, a first document "The first National Athletic Meeting was held at the Tokyo sport center on May 15. In this year, three thousands athletes took part in the Meeting from the whole nation, and the athletic meeting was the greatest scale in history." is stored in the unit 101. Also, a second document "An annual general meeting of the Nation Athletic Association was held at the Oriental hotel in the Shinagawa ward of Tokyo on December 10. The number of participators in this year is five hundreds, so that 30% is increased as compared with the number in an ordinary year." is stored in the unit 101.
An example of the word occurrence frequency information which are obtained from the first and second documents shown in FIG. 2 and is stored in the word occurrence frequency information storing unit 103 is shown in FIG. 3. In this example, occurrence frequencies for the retrieval words "hold", "national", "athletic", "sport", "center", "meeting", "Tokyo" and the like are measured, and any word relating to an article, a preposition, an auxiliary verb or the like or "be", "is", "are", "was" or "were" is not measured for convenience. The word "held" of each document is measured as the retrieval word "hold".
Thereafter, when the user intends to perform a document retrieval, the user inputs a natural language sentence (or a query document) to the input and output unit 104 as an input sentence, and the input sentence is divided into a plurality of words in the input sentence analyzing unit 105. In this case, a morphological analysis is performed for the input sentence, if necessary. Therefore, the words are extracted from the input sentence as a plurality of query words, and a weighting factor indicating an important degree of one query word is calculated for each of the query words. In general, each of the weighting factors is determined according to an occurrence frequency of a corresponding query word in the input sentence or a value input by the user. Thereafter, the query words, the occurrence frequencies of the query words and the weighting factors for the query words are stored in the input word information storing unit 106 as input word information.
An example of the input sentence "about holding the Athletic meeting" is shown in FIG. 4. An example of the input word information analyzed in the input sentence analyzing unit 105 is shown in FIG. 5. In this case, the word "holding" is analyzed as a query word "hold", and an occurrence frequency of each query word is set as a weighting factor.
Thereafter, the word occurrence frequency information stored in the word occurrence frequency information storing unit 103 is compared and collated with the input word information stored in the input word information storing unit 106 in the document rank calculating unit 107, a weighting factor for each of the retrieval words is calculated, and the documents are ranked in order of similarity to the input sentence. For example, a weighting factor for each of the query words is often calculated according to a weighting calculating equation indicated by tf*idf. Each of the documents is expressed by a multi-dimensional characteristic vector calculated from the weighting factors for the retrieval words and the occurrence frequencies of the retrieval words. In the same manner, the input sentence is expressed by a multi-dimensional characteristic vector calculated from the weighting factors for the query words and the occurrence frequencies of the query words. Thereafter, a similarity between each of the documents and the input sentence is calculated from the multi-dimensional characteristic vector of the corresponding document and the multi-dimensional characteristic vector of the input sentence according to an estimation function. For example, an inner product of the two multi-dimensional characteristic vectors is calculated or an angle between the two multi-dimensional characteristic vectors is calculated as the estimation function.
In cases where a simple estimation function is used, a similarity S1 between the first document and the input sentence is calculated as follows.
In the same manner, a similarity S2 between the second document and the input sentence is calculated as follows.
Therefore, because the similarity S1 is higher than the similarity S2, a rank for the first document is higher than that for the second document.
Thereafter, a retrieval result indicating the ranks of the documents is output to the input and output unit 104.
Accordingly, in the conventional document retrieval system 100 operated according to the conventional vector space model, because the user is not required to convert a sentence expressing a user's retrieval intention to a retrieval formula, the user can easily use the conventional document retrieval system 100. Also, because a plurality of documents are ranked in order of similarity to the natural language sentence (or a query document) expressing the user's retrieval intention, one or more desired documents matching with the user's retrieval intention can be efficiently retrieved by referring the ranks of the documents output from the document retrieval system 100.
2.2. Problems to be Solved by the Invention
However, in the conventional document retrieval system 100 operated according to the conventional vector space model, because the documents and the input sentence expressing the user's retrieval intention are converted to the multi-dimensional characteristic vectors by using the occurrence frequencies and the weighting factors, there is a drawback that one or more documents matching with the user's retrieval intention can not be retrieved with a high accuracy.
In particular, because it is difficult to express an original meaning of a document or contents of a theme of a document by using a characteristic vector in the calculation of similarity, even though contents of a particular document greatly differs from those of a necessary document matching with the user's retrieval intention, an occurrence distribution of query words in the particular document is similar to that in the input sentence, the particular document is ranked to a high level, so that there is a drawback that a plurality of documents cannot be correctly ranked in order of similarity to the user's retrieval intention.
For example, when a third document "a research meeting for a plurality of athletic teachers working in a plurality of senior high schools of the whole nation is held on August 3. This meeting is held to introduce various athletic coaching examples in an actual teaching load and discuss various problems in the athletic education performed in each of the schools" is stored in the storing unit 101, a similarity S3 between the third document and the input sentence is calculated as follows.
Therefore, because the similarity S3 is higher than the similarity S1 and the similarity S2, the third document is ranked to a higher level than those of the first and second documents. However, it is apparent that the contents of the first document match with the user's retrieval intention more than those of the third document.

Document retrieval system for retrieving a necessary document

Matsushita Electric Industrial Co., Ltd.


A driving device for installing a pipe or casing, without the use of hydraulic or pneumatic means, by capturing the rotational motion of the drill string. The driving device is placed at the top end of the pipe being (42) installed and the drill string (2) passes through the center of the device. The drill string freely rotates, advances or retracts within the driving device, until the driving device is attached (4) to the drill string when required. When the driving device is attached to the drill string, the rotational force of the drill string and any downward force applied to the drill string are captured, and used to install the pipe. The driving device uses the rotation of the drill string to impact a blow to the pipe, driving the pipe downward. The driving device uses any downward force applied to the drill string to maintain downward pressure on the pipe.

Drilling a well hole typically involves drilling to a certain depth with a drill bit mounted on a drill string, then removing the drill string from the hole in order to case the hole. The pipe or casing is driven into the hole by repeated impact. Generally it is not desirable to drill too far down before casing the hole, as the sides of an uncased hole may be susceptible to collapse and to leaks from the surrounding formation. The drill-then-case process has to be repeated several times to produce a deep hole. Drilling a hole can therefore be a time-consuming process. To maximize production and profits, it is necessary to minimize the time spent completing a hole.
Advancing a pipe into the earth usually requires costly, heavy and cumbersome equipment, including a massive driving device to either develop the impact energy or to transmit impact energy to the pipe or casing. The device must be securely mounted on a drill rig, necessitating modifications to the drill rig to be able to handle the driving device. Existing driving devices are generally large and require additional equipment for their operation, such as hydraulic pumps or air compressors. Once installed on a rig, a driving device is usually difficult to remove.
U.S. Pat. No. 3,895,680 to Cook discloses a hammer by which a pipe may be driven into the ground, without any type of drilling mechanism. A heavy, hollow ram is raised by a pair of air cylinders mounted on the outside of the ram. The ram travels downward transmitting a blow to the pipe being installed. The force of the blow is determined by the weight of the ram. The system requires an external source of compressed air and a complex control system. The force of the impact is not adjustable, as might be desired when casing in softer or less dense strata.
Drilling equipment or drilling rigs come in various sizes, with different hoisting systems and various tower configurations. A common approach is to modify the tower and equipment to adapt to the driving device. Due to the size and operational methods, several drilling rigs have towers and hoisting capabilities, which are too small to adapt to the installation of conventional casing driving equipment.
It is known in the art to case the hole while drilling as a means of improving the speed and efficiency of the drilling process. The present invention relies on a simple casing driver which is small, easy to handle and adaptable for various drilling rigs, in contrast to many of the other prior art devices, which rely on heavy, cumbersome machinery and require special handling procedures. Further, the prior art devices, generally being controlled by hydraulic or pneumatic means, require an independent source of power, and controls for that power.
U.S. Pat. No. 3,833,072 to Back illustrates a drilling machine including a casing-driving element. While the device is intended to be relatively low weight and portable, it still requires an external source of hydraulic pressure, and a complex intermittent pressure regulation system to operate the driver.
U.S. Pat. No. 4,232,752 to Hauk et al. employs a lightweight, short stroke annular piston, while increasing the rate of impact on the casing. Each individual impact is low energy, which is compensated by the increased frequency of the impacts. As in Cook, the piston is pneumatically driven. The driver further includes a complex set of valve chambers and passages to maximize the efficiency of pneumatic system.
In U.S. Pat. No. 6,029,757, Anderson et al. disclose a casing hammer assembly containing a central aperture surrounding a drill string. To drive the casing, a reciprocating hammer strikes an impact anvil surrounding the central aperture. Anderson et al. manage to avoid the use of pneumatic or hydraulic means to operate the hammer, instead reciprocating the hammer by use of an eccentric arrangement. This arrangement involves sprockets and chains driven by a rotating shaft and sleeve. The shaft itself is driven by a motor, which requires its own power source. However, the relatively complex arrangement of chains and sprockets between the shaft and the hammer leaves the entire assembly more vulnerable to failure. The use of a separate motor results in an additional part that could fail or need maintenance. Further, the entire assembly is suspended from the drilling rig above the casing pipe by a set of cable pulleys and cables, which could cause problems with the storage of the driver when not in use.
U.S. Pat. No. 6,371,209 to Allyn et al. discloses a device for the removal of casing. The device disclosed by Allyn et al. relies upon an existing pneumatic hammer drill for it to operate, and a source of power. Allyn et al. rotates the pipe or casing to install it, which requires that the ends of the each pipe be threaded.
It is one object of the invention to provide a new method of advancing pipe into the earth.
It is a further object of the invention to provide a method of advancing pipe without the need for air or hydraulics to operate the device.
It is an object of the invention to provide a driving device which is versatile, in that it may be used on virtually any existing drill rigs without modification to the drill rigs in order to use the driver.
It is a further object of the invention to provide a driving device which is easily attached to a string of drilling tools being rotated by a drilling rig or rotating device.
It is a further object of the invention to provide a driving device which, once attached to the drill string, can be selectively operated, allowing the drill crew to drill without hammering, yet without physically removing the driver from the drill string.
These and other objects of the invention will be appreciated by reference to the summary of the invention and to the detailed description of the preferred embodiment that follow. It will be appreciated that all of the foregoing objectives may not be satisfied simultaneously by the preferred embodiment or by each of the claims.

Device for simulataneously casing a hole while drilling


A slat carrier for facilitating transportation of slats to be used in an animal pen. The slat carrier includes a support assembly being designed for selectively receiving the slat to be transported. A mounting assembly is rotatably coupled to the support assembly. The support assembly is rotated with respect to the mounting assembly whereby the support assembly is designed for rotating the slat from a horizontal position to a vertical position to facilitate transportation of the slat through doorways. The mounting assembly is designed for being selectively coupled to a vehicle whereby the mounting assembly permits the vehicle to transport the slat supported by the support assembly. A wheel assembly is coupled to the mounting assembly. The wheel assembly is designed for engaging a support surface whereby the wheel assembly facilitates transportation of the support assembly across the support surface.

1. Field of the Invention
The present invention relates to load transporting devices and more particularly pertains to a new slat carrier for facilitating transportation of slats to be used in an animal pen.
2. Description of the Prior Art
The use of load transporting devices is known in the prior art. U.S. Pat. No. 3,529,736 describes a device for raising loads to allow for handling of the load. Another type of load transporting device is U.S. Pat. No. 5,441,379 having a hand cart for facilitating transportation and erecting of wall panels. U.S. Pat. No. 5,988,659 has a device for lifting and transporting panels. U.S. Pat. No. 3,795,336 has an apparatus coupled to a vehicle for lifting and transporting a building module. U.S. Pat. No. 6,270,299 has a system for securing a load of material during storage in transit. U.S. Pat. No. 1,239,771 has a truck that is positioned under a chicken coop and raised to lift the chicken coop and allow the chicken coop to be transported to a desired location. U.S. Pat. No. 5,697,309 has a apparatus for supporting a mattress and manipulating the mattress as is being sewn. U.S. Pat. No. 5,464,315 has an apparatus for compressing and lifting objects to facilitate transporting of the objects. U.S. Pat. No. 3,346,131 has a trailer having wheel assemblies that are vertically positionable to allow the for the trailer to be more conveniently loaded by a user. U.S. Pat. No. 3,410,431 has a clamp mechanism that is coupled to a forklift to allow the forklift handle materials not positioned on a pallet. U.S. Pat. No. 3,815,768 has a trailer for hauling wall panels or palletized loads. U.S. Pat. No. 4,626,017 has a trailer structure designed to transport sheets of glass or other frangible materials safely without damage to the materials. U.S. Pat. No. 4,699,558 has a cargo loader that is design for being positioned around a desired cargo and can lift the cargo.
While these devices fulfill their respective, particular objectives and requirements, the need remains for a device that has certain improved features for lifting and manipulating a slat for an animal pen.


A light pipe and an illuminating device having the light pipe are provided. The light pipe may include an optical film in a rolled shape to have a hollow conduit and a supporter surrounding a surface of the optical film. The supporter may have at least one of a protrusion and an indentation on a surface of the supporter.

1. Field
Embodiments of the present invention may relate to a light pipe and an illuminating device having the light pipe. More particularly, embodiments of the present invention may relate to a light pipe including a supporter having a plurality of protrusions, a plurality of grooves or both formed thereon.
2. Background
Illuminating devices that include a light pipe capable of transmitting light to a remote place with less transmission loss may be used in various places (for example, inside and outside a building). Light pipes may also be referred to as light conduits, light guides or light tubes, and have been used to effectively distribute light across a wide area for various purposes such as for illumination.
Light pipes may be used not only for illuminating certain points but also for illuminating whole areas. Light that transmits through a light pipe may be distributed to outside of the light pipe for illuminating certain points or for maximizing the effect of illumination.
However, illuminating devices using a light pipe may provide different illuminance levels according to their distances from a light source, and thus may not be able to achieve uniform brightness across a longitudinal direction of a light pipe.

This patent is subject to a terminal disclaimer.

Light pipe and illuminating device having the same


A method, system, and apparatus for sending data from a base station to an RF tag, whereby the RF tag comprises an "intention to write to memory" field, and the "intention to write to memory" field is written before writing the data and cleared after the data is successfully written. If the data transmission is interrupted and partial data is written to the tag, the "intention to write to memory" field will not have been cleared when the tag is checked at a later time through interrogation by a base station.

RF Tags can be used in a multiplicity of ways for locating and identifying accompanying objects, items, animals, and people, whether these objects, items, animals, and people are stationary or mobile, and transmitting information about the state of the of the objects, items, animals, and people. It has been known since the early 60's in U.S. Pat. No. 3,098,971 by R. M. Richardson, that electronic components on a transponder could be powered by radio frequency (RF) power sent by a "base station" at a carrier frequency and received by an antenna on the tag. The signal picked up by the tag antenna induces an alternating current in the antenna which can be rectified by an RF diode and the rectified current can be used for a power supply for the electronic components. The tag antenna loading is changed by something that was to be measured, for example a microphone resistance in the cited patent. The oscillating current induced in the tag antenna from the incoming RF energy would thus be changed, and the change in the oscillating current led to a change in the RF power radiated from the tag antenna. This change in the radiated power from the tag antenna can be picked up by the base station antenna and thus the microphone would in effect broadcast power without itself having a self contained power supply. In the cited patent, the antenna current also oscillates at a harmonic of the carrier frequency because the diode current contains a doubled frequency component, and this frequency can be picked up and sorted out from the carrier frequency much more easily than if it were merely reflected. Since this type of tag carries no power supply of its own, it is called a "passive" tag to distinguish it from an active tag containing a battery. The battery supplies energy to run the active tag electronics, but not to broadcast the information from the tag antenna. An active tag also changes the loading on the tag antenna for the purpose of transmitting information to the base station.
The "rebroadcast" of the incoming RF energy at the carrier frequency is conventionally called "back scattering", even though the tag broadcasts the energy in a pattern determined solely by the tag antenna and most of the energy may not be directed "back" to the transmitting antenna.
In the 70's, suggestions to use tags with logic and read/write memories were made. In this way, the tag could not only be used to measure some characteristic, for example the temperature of an animal in U.S. Pat. No. 4,075,632 to Baldwin et. al., but could also identify the animal. The antenna load was changed by use of a transistor.
Prior art tags have used electronic logic and memory circuits and receiver circuits and modulator circuits for receiving information from the base station and for sending information from the tag to the base station.
U.S. Pat. No 5,214,410, hereby incorporated by reference, teaches a method for a base station to communicate with a plurality of Tags.
Prior art tags typically use a number of discrete components connected together with an antenna. However, to substantially reduce the cost of the tags, a single chip connected to an antenna must be used. In order to increase the range of passive tags, and to conserve battery life of active tags, the minimum current necessary for the tag functions must be used.
Prior art tags may have information written to the tag memory. Typically, the information is written a single byte at a time. If the communication is interrupted after one or more bytes are successfully written, but before all the information needed to write the field is transferred, wrong information, such as an incorrect bank balance, could be carried away by the tag.

Method of flagging partial write in RF tags


Embodiments relate to MEMS devices, particularly MEMS devices integrated with related electrical devices on a single wafer. Embodiments utilize a modular process flow concept as part of a MEMS-first approach, enabling use of a novel cavity sealing process. The impact and potential detrimental effects on the electrical devices by the MEMS processing are thereby reduced or eliminated. At the same time, a highly flexible solution is provided that enables implementation of a variety of measurement principles, including capacitive and piezoresistive. A variety of sensor applications can therefore be addressed with improved performance and quality while remaining cost-effective.

MEMS devices, such as sensors, and related electrical devices, such as an application-specific integrated circuit (ASIC), are typically implemented on separate chips because the fabrication processes for each are incompatible with the other. For example, in modern CMOS technologies it can be critical to avoid high temperatures in order to preserve doping profiles, whereas high temperature steps may be necessary in steps of the electrical device fabrication. There are many disadvantages associated with two-chip solutions, including more complex and expensive packaging and the inability to implement applications requiring processing of very small signals.
More recently, so-called "MEMS first" processes have been developed for integrating MEMS and electrical devices on a single chip. Such processes, however, still present drawbacks and disadvantages, leaving room for improvement.
Therefore, there is a need for improved systems and methods that enable MEMS and electrical devices to be implemented on a single wafer.


Devices for protecting drain extended metal oxide semiconductor (DEMOS) output transistors from damage caused by electrostatic discharge (ESD) events are provided. In general, the devices include a silicon controlled rectifier (SCR) and a DEMOS transistor configured to breakdown at a lower voltage than a breakdown voltage of the output driver transistor it is configured to protect. The devices further include a pair of ohmic regions configured to trigger the SCR upon breakdown of the drain contact region of the DEMOS transistor and a collection region configured to collect charge generated by the SCR. The transistor, the pair of ohmic regions, and the SCR are respectively configured and arranged to independently set the breakdown voltage of the drain contact region, the trigger voltage of the SCR, and the holding voltage of the SCR. One of the ohmic regions may be coupled to the drain contact region of the transistor.

1. Field of the Invention
The present invention relates generally to devices and circuits providing electrostatic discharge (ESD) protection, and more particularly, to devices and circuits providing ESD protection to high voltage laterally diffused metal oxide semiconductor (LDMOS) transistors.
2. Description of the Related Art
The following descriptions and examples are given as background information only.
As is well known in the microelectronics industry, integrated circuit devices are susceptible to damage from application of excessive voltages, such as, for example, electrostatic discharge (ESD) events. In particular, during an ESD event, charge transferred within a circuit can develop voltages that are large enough to break down insulating films (e.g., gate oxides) on the device or dissipate sufficient energy to cause electro-thermal failures in the device. Such failures include contact spiking, silicon melting, or metal interconnect melting. As such, protection circuits are often connected to I/O bonding pads of an integrated circuit to safely dissipate energy associated with ESD events away from active circuitry. Protection circuits may also be connected to power supply pads or between power supply buses to prevent damage to active circuitry. In developing effective ESD protection circuitry, circuit designers may, however, be limited with regard to the particular structures used, since the protection circuit must integrate well with the remainder of the integrated circuit. For instance, integrated circuits which operate with applications of high voltages (i.e., VDD>12 volts) generally need protection circuitry configured to accommodate high voltage levels.
A transistor structure often used for high voltage applications is a drain extended metal oxide semiconductor (DEMOS) transistor, which may also be referred to in the microelectronics industry as a laterally diffused metal oxide semiconductor (LDMOS) transistor. DEMOS transistors differ from other MOS transistors in that the drain contact region is laterally displaced apart from the channel of the transistor at a greater distance than the source contact region of the transistor. As a consequence of the additional voltage drop in the drain extension region, the voltage across the channel of the DEMOS transistor is lower than a transistor having a drain contact region closer to the transistor gate and, in turn, the electric field across the gate oxide is lower. Although DEMOS transistors are effective for operations at high voltage levels, DEMOS transistors are inherently susceptible to damage from ESD events due to their device structure.
One approach in providing ESD protection for integrated circuits having DEMOS transistors is to employ a silicon controlled rectifier (SCR) type structure for transferring charge away from the transistor. For example, some conventional designs incorporate SCRs within active DEMOS transistors of an integrated circuit (i.e., transistors used for operations of a device other than protection from ESD events). Such a configuration, however, relies on drain breakdown of the active DEMOS transistor to trigger the SCR. In some cases, triggering the SCR in such a manner may not be fast enough to prevent the active DEMOS transistor from being damaged and, therefore, may not be effective for many applications. In other embodiments, an SCR may be incorporated within protection circuitry coupled to I/O bonding pads of an integrated circuit. In some cases, a protection-designated DEMOS transistor may further be included in the protection circuitry to trigger the SCR. In general, however, such configurations have limited controllability of the trigger and holding voltages of the SCR, specifically relative the breakdown voltage of the DEMOS transistor within the protection circuitry. More specifically, conventional designs do not offer layouts in which trigger and holding voltages of the SCR as well as the breakdown of the protection circuitry DEMOS transistor can be independently set. As a consequence, the level of ESD protection offered by such prior art designs is limited.
Accordingly, it would be beneficial to develop an improved ESD protection circuit suitable for use with an integrated circuit utilizing high voltage drain extended MOS transistors. In particular, it would be advantageous to develop an ESD protection device that allows the trigger and holding voltages of an incorporated SCR as well as the breakdown of an incorporated DEMOS transistor to be independently set. In addition, it would be valuable to arrange such protection circuitry in a variety of manners within an integrated circuit such that energy associated with ESD events may be safely dissipated from different types of circuit devices, including but not limited to pull down output transistors and/or pull up output transistors.

Silicon controlled rectifier electrostatic discharge clamp for a high voltage laterally diffused MOS transistor


Systems, methods, and computer readable media to automatically tailor image parameter settings used in a dental X-ray imaging system. At least one dentition characteristic and at least one non-dentition characteristic are selected and used to automatically determine at least one X-ray exposure setting for a patient to be imaged. The at least one dentition characteristic, the at least one non-dentition characteristic, and the at least one X-ray exposure setting are used to automatically generate a set of image parameter settings capable of being applied to acquired X-ray image data, being representative of the dentition of the patient.

A dentist tends to encounter dental patients having many different types of dentition characteristics. These various dentition characteristics may include, for example, a capped tooth, a tooth having a filling, bridge work, an implant, a root canal, and a cracked or broken tooth. Furthermore, these various dentition characteristics can have an affect on the quality of X-ray images of a patient's teeth as acquired by a dentist or a dental technician. For example, a particular set of X-ray machine settings may result in a good image for one type of dentition but not for another.
Further limitations and disadvantages of conventional, traditional, and proposed approaches will become apparent to one of skill in the art, through comparison of such systems and methods with the subject matter of the present application as set forth in the remainder of the present application with reference to the drawings.

System and method for dentition specific image enhancement


A fixing seat for an interface card including a first plate, a second plate and a third plate connected in a sequence, in which a step shape is formed between each two adjacent plates. A clamping portion is formed by bending the relative ends of the first plate and the second plate and a bucking ear is formed by bending each one of two ends of the third plate. An interface card can be combined with an output/input bracket of a computer housing faster and stably without using screws and any matching fixing structure is unnecessarily disposed in the computer housing and the output/input bracket so as to simplify the structure for fixing the interface card.

1. Field of the Invention
The present invention relates to a fixing seat for an interface card, and more particularly to a fixing seat used for allowing an interface card or retaining bracket to be fixed on an output/input bracket on a housing of a computer.
2. Description of Related Art
The conventional interface card (also called as expansion card) is fixed on an output/input bracket on a housing of a computer through screws. A fixing apparatus disclosed in Taiwan Patent No. 491,487 comprises a fixing element with a fixing mechanism disposed at each one of the both ends thereof. A plurality of positioning pins are disposed on the same plane of the fixing element and a plurality of fixing holes and matching holes corresponding to the positioning pins on the fixing mechanisms of the fixing element are disposed in the output/input bracket on the housing of the computer. The fixing mechanism at one end of the fixing element is connected first to the corresponding fixing hole in the output/input bracket and the one at another end thereof is then connected to another fixing hole while assembling. Finally, the positioning pins are inserted into the matching holes. Whereby, the interface card and the retaining bracket can be fixed even if the screws are not needed to connect the fixing element with the output/input bracket.
A several kinds of fixing apparatuses are respectively disclosed in the U.S. patents such as U.S. Pat. Nos. 6,693,802, 6,231,139, 5,936,835, 5,757,618 and 5,694,291, they all are used to fix an interface card on an output/input bracket on a housing of a computer.
The corresponding fixing mechanisms and fixing holes are disposed respectively on the fixing element and in the output/input bracket of the housing of a computer or corresponding screw holes are disposed in both of them for screws to be engaged with in the fixing apparatus disclosed in the all patents mentioned above.


A data processing apparatus includes a diagonal detector, a first processor, and a second processor. The diagonal detector may determine whether a red-blue data set includes data for controlling a display device to display any diagonal line, the display device including subpixels arranged in first-type lines and second-type lines that are alternately disposed, the red-blue data set including 9 data values that correspond to 9 subpixels among the subpixels, the 9 subpixels forming a 3-by-3 array that includes a center subpixel, the 9 data values including a center data value that corresponds to the center subpixel. The first/second processor may process the center data value using a first/second coefficient to produce a first/second value that corresponds to the center subpixel if the center subpixel is in the first-type/second-type lines.

(a) Field
The present invention is related to a display device, a data processing apparatus, and a method pertaining to at least one of the display device and the data processing apparatus.
(b) Description of the Related Art
A display device may include pixels each having four subpixels. The display device may operate in an 8 color mode in which 8 colors may be represented using on/off combinations of the subpixels. The 8 colors may be, for example, red, green, blue, yellow, cyan, magenta, white, and black.
The 8 color mode may reduce the power consumption of the display device. Nevertheless, the quality of the image displayed using the limited 8 colors may be unsatisfactory. The above information disclosed in this Background section is for enhancement of understanding of the background of the invention. The Background section may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Display device, data processing apparatus, and related method


The crystallization of chemical species/polymorphs comprises forming droplets of a solution of a substance with optionally different concentrations of said substance in an inert phase; producing and storing the droplets in at least one storage microchannel (1); forming crystals in all droplets; increasing the temperature in order to induce the dissolution of at least a portion of the crystals in at least some droplets; and analyzing the crystallization and dissolution process.

1. Technical Field of the Invention
The present invention relates to methodology and microfluidic apparatus/device for monitoring the crystallization of a substance and to a screening protocol comprising such methodology.
This invention more particularly features, but not exclusively, the study of polymorphism, namely, the possibility that a given molecule crystallizes in different crystalline structures without however changing chemical composition. The various crystalline forms that can be adopted by this molecule are called polymorphs.
2. Description of Background and/or Related and/or Prior Art:
The fact of predicting which polymorph is likely to crystallize is of great importance in chemical and pharmaceutical processes, insofar as each polymorph of a given substance has specific physical properties. Compare the following publications: J. Bernstein, J. Phys. D. Appl. Phys., 26, 66 (1993); K. Sato, J. Phys. D. Appl. Phys., 26, 77 (1993); and J. Bernstein, J. Davey and J. O. Henck, Angew. Chem. Int. Ed., 88, 3440 (1999).
However, complete understanding of the complexity of the process of crystallization in solution is lacking from the prior art. Such a lack is in particular due to existing links from the thermodynamic characteristics of phase diagrams and the kinetics of phase transitions (particularly nucleation), to the experimental difficulties in obtaining reliable and reproducible measurements, because of the presence of impurities, and to the large number of parameters, such as the pH, the temperature or the presence of solvent, which play an important role. To illustrate the latter point, see the following publications: J. W. Mullin, Crystallisation (Butterworth-Heinemann, Oxford, 2001); A. C. Zettlemoyer, Nucleation (Marcel Dekker, New York, 1969); N. Rodriguez-Hornedo and D. Murphy, Journal of Pharmaceutical Sciences 88, 651 (1999); D. Kashchiev, D. Clausse and C. Jolivet-Dalmazzone, J. Colloid Interface Sci., 165, 148 (1994).
High-flow-rate techniques are likely to improve this understanding, by providing the possibility of greater screening of the crystallization conditions. In addition, microfluidics appears to be a good gateway for such experiments, insofar as it offers very precise control, through the design of specific kinetic pathways in phase diagrams. With regard to the latter aspect, refer to the following publications: C. L. Hansen, S. Classen, J. M. Berger and S. R. Quake, J. Am. Chem. Soc., 128, 3142 (2006); J. Leng, B. Lonetti, P. Tabeling, M. Joanicot and A. Ajdari, Phys. Rev. Lett., 96, 084503 (2006); C. J. Gerdts, V. Tereshko, M. K. Yadav, I. Dementieva, F. Collart, A. Joachimiak, R. C. Stevens, P. Kuhn, A. Kossiakoff and R. F. Ismagilov, Angew. Chem. Int. Ed. Engl., 45, 8156 (2006).
In addition, microfluidics offer the possibility of screening a very large number of physico-chemical systems using very small amounts of compounds, typically varying from the range of nanoliters (nl) to microliters (μl). With regard to the latter point, namely the "Lab on chip" technology, also compare the following publications: C. L. Hansen, E. Skordalakee, J. M. Berger and S. R. Quake, Proc. Natl. Acad. Sci., USA 99, 16531 (2002); D. L. Chen and R. F. Ismagilov, Current Opinion in Chemical Biology, 10, 226 (2006); K. Shinohara, T. Fukui, H. Abe, N. Sekimura and K. Okamoto, Langmuir 22, 6477 (2006); B. Zheng, J. D. Tica, L. S. Roach and R. F. Ismagilov, Angew. Chem. Int. Ed., 43, 2508 (2004).

Crystallization of chemical species/polymorphs and microfluidic apparatus and screening methodology therefor


In one embodiment, a ferromagnetic frame for use in an MRI system comprises first and second opposing ferromagnetic elements magnetically coupled by a flux return path. First and second poles are provided, separated by a distance to define an imaging volume therebetween. The first pole is movably supported with respect to the first ferromagnetic element to vary the distance between the first and second poles. The first pole may have a first, imaging position and a second position wherein the first pole is farther from the second pole than in the first position. When the first pole is in the first, imaging position, a gap is provided between the first pole and the first ferromagnetic element. The second pole is supported by the second ferromagnetic element. When the first pole is in the second position, the imaging volume is made larger, providing room for medical personnel to access a patient. Performance of medical procedures on the patient is thereby facilitated. The flux return path may be two or more opposing ferromagnetic posts or plates, for example. Magnet assemblies, MRI systems, methods of conducting an MRI procedure and methods of conducting a medical procedure are also disclosed.

Magnetic resonance imaging ("MRI") is a well-known, highly useful technique for diagnosing abnormalities in biological tissue. MRI can detect abnormalities that are difficult or impossible to detect by other techniques, without the use of x-rays or invasive procedures.
During an MRI procedure, the patient is inserted into an imaging volume of a primary field magnet. The magnet generates a static magnetic field through that causes the vector of the angular momentum or spin of nuclei containing an odd number of protons or neutrons to tend to align with the direction of the static magnetic field. A transmitting antenna proximate to the imaging volume emits a pulse or pulses of radio frequency energy. The radio frequency energy has a particular bandwidth of frequency, referred to as the resonant or Larmor frequency, that shifts the vectors of the nuclei out of alignment with the applied magnetic field. The spins of the nuclei then turn or "precess" around the direction of the applied primary magnetic field. As their spins precess, the nuclei emit small radio frequency signals, referred to as magnetic resonance ("MR") signals, at the resonant or Larmor frequency, which are detected by a radio frequency receiving antenna tuned to that frequency. The receiving antenna is typically positioned within the imaging volume proximate the patient. Linear, time-varying gradient magnetic fields are superimposed onto the static magnetic field to spatially encode the MR signals emitted by the nuclei and to define a particular image slice. After the cessation of the application of radio frequency waves, the precessing spins gradually drift out of phase with one another, back into alignment with the direction of the applied magnetic field. This causes the MR signals emitted by the nuclei to decay.
The same antenna may act as the transmitting and receiving antenna. The MR signals detected by the receiving antenna are amplified, digitized and processed by the MRI system. Hydrogen, nitrogen, phosphorous, carbon and sodium are typical nuclei detected by MRI. Hydrogen is most commonly detected because it is the most abundant nuclei in the human body and emits the strongest MR signal.
The rate of decay of the MR signals varies for different types of tissue, including injured or diseased tissue, such as cancerous tissue. By correlating the gradient magnetic fields and the particular frequency of the radio frequency waves applied at various times with the rate of decay of the MR signals emitted by the patient by known mathematical techniques, the concentrations and the condition of the environment of the nuclei of interest at various locations within the patient's body may be determined. This information is typically displayed as an image with varying intensities, which are a function of the concentration and environment of the nuclei of interest. Certain abnormalities in tissue, such as tumors, may be identified.
MRI can be of great assistance during medical procedures. For example, MRI has been used for pre-operative and postoperative imaging to identify and assess the condition of tissue of interest. MRI has also been used during fine-needle aspiration cytology to help the doctor guide the needle to the site of interest, such as a tumor. See, for example, U.S. Pat. No. 6,208,145 B1, assigned to the assignee of the present invention and incorporated by reference, herein. MRI has also been used in stereotactic neurosurgery. The advance of other instruments, such as a catheter or an endoscope, can also be followed and guided to a site of interest by MRI. See, for example, U.S. Pat. No. 6,249,695 B1 and U.S. Pat. No. 5,647,361, which are both assigned to the assignee of the present invention and incorporated by reference, herein. A catheter guided to a site of interest by MRI can be used in the treatment of tissue, such as a tumor, by delivering medication, isotopes or other such treatments, for example. MRI may also be used to monitor the affect of a treatment on the tissue, as the treatment is being conducted. See, for example, U.S. Pat. No. 6,208,145 B1 and U.S. Pat. No. 6,280,383 B1, both assigned to the assignee of the present invention and incorporated by reference herein.
To conduct surgery, the imaging volume needs to be large enough for one or more surgeons and other medical personnel to have clear and unimpeded access to the patient. In U.S. Pat. No. 6,208,145 B1, assigned to the assignee of the present invention and incorporated by reference herein, open MRI assemblies are disclosed wherein a physician or other medical personnel may conduct activities within the frame of the assembly, adjacent to the patient. In one embodiment, a ferromagnetic frame comprises two opposing vertical ferromagnetic plates connected to two opposing ferromagnetic pole supports. Opposing ferromagnetic poles extend towards each other, from the pole supports. Resistive or superconductive coils wrapped around the poles provide magnetic flux through the ferromagnetic frame. An imaging volume is defined between the opposing poles, for receiving at least a portion of a subject for imaging. The poles are above and below the patient. The regions around the sides of the patient are open, decreasing any claustrophobic reaction the patient may experience. In addition, medical personnel may access the patient through the open side regions, enabling performance of medical procedures on the patient while the patient is within the imaging volume and undergoing MRI.
The magnet assembly of the MRI system may define a room for conducting a medical procedure and may be large enough to contain an entire surgical team. The Quad™ 7000 and Quad™ 12000 Open MRI Systems, available from FONAR Corporation, Melville, N.Y., are also suitable for performing surgery and other medical procedures.
MRI systems in accordance with U.S. Pat. No. 6,208,145 B1 provide about 18–19 inches of open space between the opposing poles of the assembly. Additional room for the doctor to maneuver proximate imaging volume during a medical procedure may be provided by tapering the upper pole, as described in U.S. Pat. No. 6,346,816 B1, assigned to the assignee of the present invention and incorporated by reference herein. Additional room may also be provided by tapering portions of the bottom of a canopy of insulative material which typically covers the upper (and lower) pole and accessories, as described in U.S. Ser. No. 09/919,286, filed on Jul. 31, 2001 also assigned to the assignee of the present invention. The recessed or tapered portions enable the doctor or other such personnel in the room to lean into the imaging volume during a medical procedure. Two recessed portions are typically provided, symmetrically arranged around the periphery of the canopy.
Despite these improvements in the design of open MRI magnet assemblies to make them more conducive for conducting surgery, it would be advantageous to provide further room for medical personnel to access a patient in an imaging volume of an MRI magnet assembly.
In U.S. Pat. No. 6,029,081, several magnet assemblies are disclosed wherein one or both poles may be moved with respect to the imaging volume to provide room to conduct medical procedures. In one embodiment, the entire magnet assembly is supported on rollers or wheels on a track and can be moved along the track, away from the patient, when necessary. The assembly may be moved back into an imaging position when MR images are needed. In another embodiment, a portion of a magnet supporting an upper pole is rotatable or pivotable to move the upper pole out of the imaging volume. In another embodiment, a portion of the magnet and the pole are raised by a lifting mechanism to enlarge the imaging volume. The lifting mechanism is movable along a track on the ceiling to move the magnet and pole out of the way. In another embodiment, the magnet and both of the supported poles are separable in three directions, horizontally. These designs are complex and impractical. Movement of the ferromagnetic elements would require that the magnetic field be shut down in all but the smallest magnets. After such a shut down, when MRI is desired, the magnet would need to be reassembled and allowed to warm up, causing long delays during the medical procedure.


A scale (1) having a scale housing (3) serving to house the weighing mechanism and the weighing electronics, which stands on a support base on at least three support points (5,5′), is designed to be connectable to and disconnectable from a display and operating unit (6). A connection element (9) is provided to produce a mechanical coupling between the scale (1) and the display and operating unit (6), which can be attached to the bottom side of the scale housing (3) and is designed to be supported on at least two support points (5) of the scale (1) and can be engaged in a self-locating way in a third point on the bottom side of the scale housing (3).

Such scales are preferably used in laboratories, at production sites, or in warehouses. In these locations, the available work space is frequently limited and therefore one of the requirements for such a scale is its flexibility with regard to its setup location and the positioning of the scale housing and the display and operating unit in relation to each other.
Scales whose scale housing can be connected to their display and operating unit or can be positioned separately therefrom at the work space are known in the related art. For example, U.S. Pat. No. 6,633,007 B1 describes a scale in which the display and operating unit may be placed both adjacent to a housing and also at a distance therefrom. To store excess length of the connection cable between the scale housing and the display and operating unit, a shaft is positioned on the floor of the housing, in which the cable is freely movable as it is pulled out and pushed in. The display and operating unit is guided on the housing of the scale by using an adapter. In this case, the scale housing and the display and operating unit stand on the support base independently from one another.
Scales are known which are optimized with regard to a low overall height, and in which the height of the free space located between the support base, such as the working table, and the bottom of the scale housing is only a few millimeters, so that an arrangement of a shaft described above can not be realized. The attachability and easy removability of the display and operating unit to and from the housing is particularly difficult if the requirement exists of being able to place the display and operating unit both adjacent to the housing and also at a distance therefrom.
It is therefore the object of the present invention to provide a stable anchoring of the display and operating unit, when it is placed directly on the scale, particularly a scale of low construction, in which scale the display and operating unit can be placed both adjacent to the scale and also at a distance therefrom, wherein connecting parts neither project from the scale nor from the display and operating unit when the display and operating unit is placed at a distance from the scale.

Scale having a display and operating unit


A NMQL grinding device of ultrasonic vibration assists grinding fluid micro-channel infiltration, and solves the problem that nanofluids are difficult to fully infiltrate the grinding zone in the prior art. Fully considers the impact of thickness of undeformed grinding debris on the grinding process and the lubrication state of single grains during material removal in the grinding process, the advantage of ultrasonic vibration assistance on improving the lubri-cooling performance of NMQL grinding is effectively achieved. According to the solution, the device includes an ultrasonic vibration mechanism capable of adjusting the spatial position of ultrasonic vibrators, the mechanism being arranged on a worktable; a NMQL grinding mechanism, arranged above a workpiece fixing table; and a grinding force measuring mechanism, including a dynamometer and a grinding force controller connected with the dynamometer, the dynamometer being arranged at the bottom of the ultrasonic vibration mechanism.

With the continuous development of broad machining fields of machinery, automobiles, aerospace, optical components and the like, a large number of parts with increasingly high performance requirements have emerged, and precision and ultra-precision machining technologies have become increasingly important. The conventional grinding process produces large grinding force and high grinding temperature, which aggravates the wear of a grinding wheel and the damage of a machined surface, and seriously restricts the machining accuracy and machining efficiency of the parts, so a new grinding process is urgently needed to solve such problems. Ultrasonic vibration assisted NMQL grinding is one of the methods to solve such problems.
Ultrasonic vibration grinding is a composite machining method based on vibration theory and cutting theory. This grinding method is fundamentally different from previous grinding in that high-frequency electric oscillation signals generated by an ultrasonic generator are converted into ultrasonic frequency mechanical vibration by an ultrasonic transducer during grinding, and the amplitude of ultrasonic vibration is amplified by a horn to drive a tool grinding wheel to generate a vibration of a corresponding frequency, so that the tool periodically cuts a workpiece, that is, the tool grinding wheel also produces high-frequency vibration at high-speed rotary grinding. When the ultrasonic vibration is applied to a process system, the interaction conditions between the grains and the contact surfaces of the workpiece are quite different from those of ordinary grinding. The special mechanism of the ultrasonic vibration grinding significantly improves the grinding efficiency, reduces the grinding temperature and prolongs the service life of the grinding wheel, and the ultrasonic vibration grinding improves the grinding ability to difficult-to-machine materials. Moreover, the ultrasonic vibration causes the grains to produce an intermittent cutting action, the impact load causes the workpiece material to be convolved more easily, and more micro crack propagation in the cutting zone causes the grinding force and the friction coefficient to decrease. The plastic deformation of the material during the grinding process mainly occurs in the stages of sliding friction and plowing. Since the ultrasonic vibration grinding is pulsed intermittent grinding, the proportions of sliding friction and plowing are relatively reduced, then the specific grinding energy is reduced, and the surface thermal damage is also significantly reduced.
Minimum quantity lubrication (MQL) is an environment-friendly grinding technique in which a minimum quantity of lubricating fluid and compressed gas are mixed, atomized and then sprayed to a grinding zone by a nozzle to achieve cooling lubrication. When the minimum quantity of lubricating fluid is sprayed into the grinding zone, the high-pressure gas can achieve cooling and grinding debris removal, and the lubricating fluid takes away the heat generated by the grinding process to reduce the temperature of the grinding zone. The lubricating fluid transported by the high-pressure gas to the workpiece interface of the grinding wheel adheres to the surface of the workpiece and the grains to form a lubricating oil film having a certain anti-friction and anti-wear effect, which can achieve a good lubricating effect and reduce the friction coefficient and the specific grinding energy, thereby reducing the grinding force. The MQL machining technique can be said to combine the advantages of both dry cutting and cast grinding. On the one hand, the quantity of the grinding fluid is minimum, and the flow rate of the grinding fluid per unit grinding wheel width for MQL is 30˜100 ml/h. Not only is the quantity of the grinding fluid a few thousandths or even a few ten thousandths of the quantity of the conventional machining method, but also the lubrication effect is improved. Moreover, the lubricating fluid used in the MQL grinding process can be synthetic ester or vegetable oil with good natural degradability, the treatment cost of the lubricating fluid is almost zero, and the pollution to the environment and the harm to human body are extremely low. On the other hand, compared with dry grinding, due to the addition of the lubricating medium, the lubrication state of the grinding zone is significantly improved, the friction between the grinding wheel and the workpiece is reduced, and the machining efficiency is effectively improved.
NMQL is an upgrade and enhancement of the MQL, and its main point is: based on the MQL, an appropriate quantity of nano particles are added to the degradable base oil to prepare nanofluid, and then the nanofluid is mixed and atomized with high-pressure gas and then sprayed to a grinding zone in the form of droplets by a nozzle to achieve cooling lubrication. NMQL grinding is a novel high-efficiency, environment-friendly, clean and low-carbon lubrication method based on the above theory. In the mixture of the nanofluid and the compressed gases sprayed to the grinding zone, the compressed gas achieves the effects of cooling, removing grinding debris and carrying the lubricating fluid; and the nanofluid plays a role in lubrication, friction reduction and wear resistance. The NMQL not only solves the deficiency of the cooling performance of the lubricating fluid in the grinding zone, but also significantly improves the lubrication performance. Although the NMQL has such a good cooling lubrication effect, compared with the cast lubrication method, the nanofluid hardly achieves all-directional lubrication to the grains in operation. Specifically, the nanofluid hardly enters the gaps between the grains and the workpiece and the gaps between the grains and the grinding debris, but generates a large amount of grinding heat, which causes severe surface burn on the surface of the workpiece, and also increases the adhesion of the grinding debris to the grains and the blockage of the grinding wheel.
In the prior art, an ultrasonic vibration three-dimensional ultrasonic spiral grinding method was disclosed, where the axial ultrasonic vibration of a grinding wheel causes the trajectories of grains on the surface of a workpiece to interfere with each other, thereby achieving a reduction in roughness; and at the same time, the radial ultrasonic vibration of the grinding wheel causes the maximum cutting depth of the grains to increase, and the grains implement intermittent cutting, thereby achieving a reduction in the grinding force and an increase in the material removal rate. This method can improve the quality of the machined surface, reduce the surface damage and improve the production efficiency, and is therefore suitable for efficient and precise machining of difficult-to-machine materials. However, this method can only achieve purely radial ultrasonic vibration, but cannot achieve maximum separation between the grinding wheel and the workpiece with the increase of grinding depth, the grinding fluid cannot furthest lubricate the grinding wheel and the workpiece, the cooling lubrication effect of the nanofluid cannot be fully exerted, and the surface burn of the workpiece is not solved.
The prior art discloses a grinding process for machining a solid carbide tool by ultrasonic vibration assisted grinding. The grinding process avoids local instantaneous high temperature by using the advantages of grinding debris removal and heat dissipation of ultrasonic vibration, and effectively prevents grinding cracks and grinding burns by optimizing the grinding parameters of the solid carbide tool, so that the machined surface has good quality. However, this grinding process does not couple NMQL with the ultrasonic vibration, does not improve the lubrication effect of the nanofluid by the ultrasonic vibration, so the cooling lubrication effect is poor.
The prior art discloses a NMQL experimental system and method for ultrasonic vibration assisted grinding. The experimental system comprises a magnetic worktable, a workpiece clamp, a dynamometer and an ultrasonic vibration device; the ultrasonic vibration device comprises a tangential ultrasonic vibration device, an axial ultrasonic vibration device, a vibrating base and a radial piezoelectric ceramic plate fixed on the vibrating base; the tangential ultrasonic vibration device and the axial ultrasonic vibration device are respectively fixed on the vibrating base and simultaneously fixed on the magnetic worktable by holders, the dynamometer is fixed on the vibrating base, and the workpiece clamp is fixed on the dynamometer. The experimental system realizes simultaneous on-line detection of grinding force and grinding temperature, saves time, and avoids machining errors caused by multiple times of assembly. However, the radial ultrasonic vibration of the device is only provided by the piezoelectric ceramic plate, so the radial ultrasonic vibration is not reliable; the manufacturing cost of the ultrasonic vibrator holders in the device is high, and the ultrasonic vibrators are inconvenient to fix on the holders.
Based on the above, the prior art does not apply ultrasonic vibration to the normal direction and tangential direction of the midpoint of the contact arc length between the grinding wheel and the workpiece. The prior art does not study the influence of the grinding debris thickness and the contact arc length between the grinding wheel and the workpiece on the MQL from the microscopic angle under the ultrasonic vibration condition. The thickness of the undeformed grinding debris has a great influence on the grinding process, and it not only affects the force acting on the grains, but also affects the specific grinding energy and the temperature of the grinding zone, thus causing the wear of the grinding wheel and affecting the integrity of the machined surface. Moreover, in the case where the workpiece feed speed is low, the energy conversion is slow, the grinding depth is large. Which results in the long contact arc length between the grinding wheel and the workpiece, the contact area is large, the grains are subjected to a long time, and a part of the energy is slowly transferred to the workpiece, so that the surface of the workpiece is easily burnt.
Therefore, a new research design is required for a NMQL grinding device of ultrasonic vibration assisted grinding fluid micro-channel infiltration.

Nanofluid minimum quantity lubrication grinding device of ultrasonic vibration assisted grinding fluid micro-channel infiltration


A temperature and humidity control apparatus includes a humidity control section for controlling humidity when a flow rate of a low temperature fluid in a cooling dehumidifier composed of a heat exchanger is determined; a heater control section for controlling temperature when a flow rate of a high temperature fluid in a heater; and a predicting device for predicting an amount of temperature change caused by an operation of the cooling dehumidifier. The amount of predicted temperature change is canceled when the flow rate of the high temperature fluid in the heater is determined in the heater control section, and the flow rate of the high temperature fluid in the heater is determined so that the setting temperature can be realized.

The present invention relates to a temperature and humidity control apparatus in an air-conditioning system used for drying photosensitive materials and also used for general purposes.
Conventionally, the following temperature and humidity control methods are used for controlling the temperature and relative humidity in a workshop to be accurately constant.
(1) One method is described as follows. Temperature control is conducted independently from humidity control, wherein temperature control is conducted by a cooling dehumidifier and a heater, and humidity control is conducted by a cooling dehumidifier and a humidifier. When cooling is temporarily conducted by the temperature control and dehumidification is conducted by humidity control, a larger opening is adopted for the cooling dehumidifier.
(2) Another method is described as follows. After temperature and humidity have been temporarily controlled lower than the set values using a cooling dehumidifier, temperature is controlled by a heater, and humidity is controlled by a humidifier.
(3) Still another method is described as follows. The opening of a cooling dehumidifier is added to the opening of a heater and also added to the opening of a humidifier, and an amount of forward control corresponding to the entrance temperature and humidity is added to each opening (disclosed in Japanese Patent Publication Open to Public Inspection No. 181112/1989).
Temperature and humidity of the discharge side air of a heat exchanger, which are used when the control system of the heat exchanger is designed, are expressed as follows.
(4) A heat exchanger is divided into a finite number of portions, and the temperature of the discharge side air is expressed in accordance with the heat balance in each portion, which is disclosed in the thesis written by Hideaki Kano, the title of which is "Discrete System Approximate Model of the Distribution Constant System" in the magazine of "Measurement and Control" vol. 19-11, 1044/1050 published in 1980.
(5) Still another method is described as follows. A heat exchanger used as a cooling dehumidifier is divided into a finite number of portions. In accordance with the heat balance and the material balance in each portion, the temperature and humidity of the discharge side air are simultaneously expressed when the humidity close to a heating surface is given to a model, which is disclosed in the thesis "S. Chandra Sheker and G. Green, Dynamic Study of a Chill Water Cooling and Dehumidifying Coil, ASHRAE TRANSACTIONS, 76-3141, 36/51 (6,1970)".
Five methods are described above, however, however, each method has a disadvantage, which will be described as follows.
In the case of method (1), when the temperature and humidity setting is in a condition of cooling and dehumidifying, either the control of temperature or the control of humidity is neglected, so that the control deviation is increased.
In the case of method (2), after air has been unnecessarily cooled and humidified, it is heated and humidified again. Therefore, energy is wasted, and this method is not economical.
FIG. 6 is a graph showing a state of control of temperature and humidity in the case of method (3). FIG. 7 is a graph showing the changes of an amount of high temperature fluid in the heater, an amount of low temperature fluid in the cooling dehumidifier, and an amount of steam in the humidifier.
In the case of method (3), the following problems may be encountered. According to FIGS. 6 and 7, in order to cancel an amount of cooling conducted by the cooling dehumidifier, the opening of the cooling dehumidifier is added to the opening of the heater, however, the effect provided by a simple addition is not so high due to a difference between the cooling dehumidifier and the heater and also due to a difference between the low and high temperature fluids. Therefore, an adjustment of trial and error is conducted in this method. Concerning the addition of an amount of feed forward control corresponding to the entrance temperature and humidity, the circumstances are the same as those described above. Even after the adjustment conducted in the manner of trial and error, there is a possibility that the temperatures of the low and high temperature fluids fluctuate. In this case, it is impossible to provide a sufficiently high accuracy.
In the case of method (4), only a change in temperature at an outlet of the heat exchanger is expressed, and simultaneous changes in the temperature and humidity are not expressed.
In the case of method (5), simultaneous changes in the temperature and humidity in the cooling dehumidifier are expressed by the Lewis Number, which is a constant, and humidity Wf, which is a humidity at a position close to the surface of heat transfer tube, wherein Wf changes in accordance with a wet condition on the surface of heat transfer tube. The Lewis Number is a constant at all times, however, the value of Wf changes in accordance with a wet condition of the surface of the heat transfer tube portion between air and low temperature fluid when the humidity of the entrance portion is changed. Further, it is necessary to change the value of Wf in accordance with a flow amount region to be used for each row. Therefore, it is difficult to use this method when the entrance humidity is frequently changed or the flow amount is changed. Further, it is necessary to respectively find a film coefficient of heat transfer on the air side, a coefficient of heat-transfer of the heat transfer tube portion between air and low temperature fluid, and a film coefficient of heat transfer on the low temperature fluid side. In order to find the above coefficients, it is necessary to arrange temperature sensors to measure the temperature distribution in the cooling dehumidifier.
Due to the foregoing, it can be said that the temperature and humidity are difficult to be predicted under the various temperature and humidity conditions, using the prediction apparatus of (4) and (5).

Temperature and humidity control apparatus and temperature and humidity prediction apparatus used therefor


A flat workpiece transport apparatus having a movable arm and an end effector. The end effector is connected to the arm. The end effector has a movable grip for holding a flat workpiece on the end effector. The end effector has a grip actuator operably connected to the movable grip. The grip actuator has more than one actuation members and a resiliently flexible member connecting the more than one actuation members. Each actuation member actuates at least one corresponding grip element of the movable grip to capture or release the workpiece. Flexure of the resiliently flexible member effects movement of at least one of the more than one actuation members for actuation of the at least one corresponding grip element. The resiliently flexible member is sandwiched by substantially rigid portions of the more than one actuation members.

1. Field of the Invention
The present invention relates to a device for gripping flat, thin, workpieces, on an end effector used for handling and transporting such workpieces.
2. Brief Description of Related Developments
Common in the processing of semiconductor substrates and similar devices is the desire to move the substrate from station to station, into and out of various chambers at a given station, and amongst multiple orientations as indicated by the overall processing layout. To accomplish this, the substrate is generally releasably held on a holding platform or end effector as a suitable transport mechanism or robot.
The throughput of any processing system is dependent on the speed at which the substrate can be moved. Therefore each movement in each step of the process has a direct impact on throughput. There is a need to speed up the movements of the end effector at all phases of the process. This has placed increased burdens on the means used to secure the substrate on the end effector platform in order to avoid displacement of the substrate.
There are many types of conventional handling systems specifically designed for holding workpieces like semiconductor wafers, and transporting them between workstations and or wafer cassettes. Among these are passive holding systems using an annular ring member to position a wafer and an annular flange or lip to support the workpieces, for example, in U.S. Pat. No. 4,584,045, U.S. Pat. No. 4,749,330, and U.S. Pat. No. 5,334,257, which are hereby incorporated by reference in their entirety. Many of these conventional types of passive holding systems may not provide sufficient grip for use on high speed robots.
Another conventional approach to increase holding capability is to provide an active grip that uses a vacuum platform, wherein a flat upper surface with vacuum ports is brought into contact with the underside of a workpiece and suction is applied at the port to secure the workpiece to the platform, U.S. Pat. No. 4,770,590 U.S. Pat. Nos. 5,064,030, 5,135,349 and 5,765,444, which are hereby incorporated by reference in their entirety, disclose such a means.
Still another approach to solve these pressing problems makes use of a Bernoulli effect on the top side of the workpiece. U.S. Pat. Nos. 5,080,549 and 5,324,155, which are hereby incorporated by reference in their entirety, disclose such a system wherein a paddle with appropriately placed gas exhaust ports is brought into close proximity with the top side of a workpiece. Nevertheless, the gripping systems employing suction effects for holding the workpieces are complex (employing complex tight fittings at movable joints) and expensive to manufacture. Moreover, such system cannot operate in a vacuum environment.
Still another conventional approach for holding workpieces on transports is the use of one or more movable mechanical grippers such as gripping arms, fingers or tabs. The grippers are moved relative to one another to change the distance between contact surfaces which, when brought to a gripping position, clamp the workpiece in place relative to the transport assembly. In systems of this type it is advantageous to construct the contact surface in a manner that allows engagement of the workpiece at its circumference/outer edge.
Gripping mechanisms that are designed to provide movement of the contacting and clamping members are described in U.S. Pat. Nos. 6,174,011 and 6,322,312, which are hereby incorporated by reference in their entirety. The '011 patent describes a circular disc that supports the substrate. The circumference of the disc is expanded and contracted by the operation of a series of radially oriented leaf springs to allow three circumferentially displaced holding fingers to disengage and engage the substrate. In the '312 patent a pair of clamp fingers are spring biased to engage the substrate from one side to force the substrate into engagement with opposing fixed clamp fingers. The above illustrate the problems with conventional transport apparatus with conventional gripping mechanism. For example, the conventional gripping mechanism described in U.S. Pat. No. 6,174,011, which is hereby incorporated by reference in its entirety, provides a gripper with actuable holding fingers distributed around the perimeter of substrate that results in low force contact between holding fingers and substrate edge during closure of the gripper and transport system movement (i.e., inertial efforts between substrate and holding fingers). However, the gripping mechanism in this case is complex and costly to manufacture (e.g. the flexible radial spokes 40 are expensive and time consuming to cut even when using a wire cutting tool). The examples of the gripping mechanisms described in U.S. Pat. No. 6,322,312, which is hereby incorporated by reference in its entirety, generally include grippers with actuable clamp fingers on but the proximal side (i.e. closest to the base of the end effector) of this substrate (fixed fingers are located on the distal side providing a gripper that is not as effective in holding the substrate at high transport speeds and also suffers from lower gripper closure speeds), and grippers having all clamp fingers that are actuable but with a complex actuation system. The transport apparatus in accordance with the exemplary embodiments of the present invention overcome the problems of the conventional substrate transport apparatus as will be described in greater detail below.