The present invention contemplates a simple and inexpensive, but effective method for constructing straight walls at a building site without use of nails or other fastening means. Appropriately flanged metal I-beam studs are erected with the flanges in the direction of the wall, and expanded polyurethane foam is applied, such as by spraying, to a desired thickness between the I-beam flanges, thereby acting as a fastener and providing insulating properties. A fiberglass-cementitious mixture is then applied to provide a very hard, smooth, waterproof and durable surface of very high fire rating. The invention is equally applicable to interior walls, exterior walls, and roof panels.

1. Field of the Invention
The invention relates to building construction materials, a method for making construction elements of a building, and an expansion joint to allow for thermal expansion or contraction of a building constructed from such construction elements. More particularly, the invention provides an underlying expanded polyurethane foam supported from appropriately flanged metal I-beam studs, the underlying foam supporting a hard, smooth, durable layer of sprayed-on mixture of fiberglass and cementitious composition which sets to form a fire-resistant, waterproof and durable external surface, firmly secured to the foam with the aid of an appropriate bonding agent. The panels are useful as structural walls or in forming a roof.
2. Description of the Prior Art
Preformed wall panels for use in building construction are known in the prior art. For example, Lemelson in U.S. Pat. No. 3,298,883, issued Jan. 17, 1967, discloses a wall, ceiling, or a partition made from a curved wall panel comprising a flexible array of self-supporting strips shaped to deform and jointed together to form a honeycomb structure. A cellular plastic polymeric material, such as expanded polyurethane, can comprise the frame supporting cellular sheet or slab on which a mortar or filler material can be sprayed to form a hard shell when it hardens. However, the simplicity, conformity with traditional standards of construction, and cost effectiveness of a straight wall or roof panel made from appropriately flanged metal I-beam studs are not present in the Lemelson patent teachings.
Also known in the prior art is a method of constructing a roof having a thermal insulating layer in pre-cut blocks, blanks or sheets, preferably a closed cellular material. The exterior surface is formed of material such as concrete block covered with a roof wearing surfacing composition. Such a roof construction requires rather cumbersome assembly procedures, including extensive cutting, shaping, and fitting operations to conform the individual component parts with the overall roof size requirements. Moreover, such a roof construction appears to have utility only for roofs of flat configuration, which are capable of withstanding foot traffic, rather than roof constructions of the conventional peaked or sloping configuration. Other patents showing an insulated roof construction include U.S. Pat. No. 3,094,447, issued June 18, 1963 to Chamberlain, and U.S. Pat. No. 3,698,972, issued Oct. 17, 1972 to Lenzner.
The prior art further discloses use of insulating joints for joining heat insulating elements and for providing a strong rigid structure therebetween, such as in U.S. Pat. No. 3,251,912, patented May 17, 1966 by Fish. A channel filled with foamed insulating material is bonded to adjacent insulating elements by an adhesive to form a firm joint. Such a joint, however, does not appear to allow for thermal expansion or contraction of the external surface.
U.S. Pat. No. Re. 28,976, reissued Sept. 28, 1978 to Zinn, discloses a method for forming and assembling a sound attenuating wall between fixed structure channels.
It is also known to prepare a cementitious composition of matter for spray forming a concrete layer which hardens to a firm shell, used as a substitute for plaster, gunite, or the like, in building construction. Such a material is manufactured by Owens-Corning and marketed under the trade name "BlocBond", which material is a mixture of Portland cement, hydrated lime, calcium chloride, calcium stearate, and alkali-resistant fiberglass filaments having a length of about one-half inch. Such a composition, however, does not ordinarily effectively bond to polyurethane foam, such as can be applied by spraying and curing to form a stable, insulating, construction material substrate, as those skilled in the art are aware.

Method of forming structural walls and roofs


A semiconductor device includes a semiconductor substrate and a semiconductor element arranged on a predetermined surface side of the semiconductor substrate. The semiconductor element includes: a first region portion at which a first conductivity type semiconductor region is arranged on the surface side of the semiconductor substrate; a second region portion at a position separated from the first region portion; and a gate electrode arranged between the first region portion and the second region portion through an insulating film. In the first region portion, a first conductivity type semiconductor region is arranged. In the second region portion, a first conductivity type semiconductor region and a second conductivity type semiconductor region are alternately arranged. The semiconductor structure portions with a variety of types having ratios of the first conductivity type semiconductor region to the second conductivity type semiconductor region different from each other are provided at the second region portion.

A semiconductor device, for example, as disclosed in Patent Literature 1 is provided as a lateral semiconductor device such as an LDMOS. In an example of FIG. 1 in Patent Literature 1, an N-conductive type drain region 104 and a source region 106 are provided on a surface side of a semiconductor substrate. In the source region 106, an N-conductive type diffusion region and a P-conductive type diffusion region are alternately disposed. A gate electrode 109 is disposed between the drain region and the source region through an insulating film on the semiconductor substrate.

Semiconductor device having semiconductor elements on semiconductor substrate


Systems, methods and non-transitory computer readable media for allowing a user to switch between wearable items that have been paired or associated with an electronic device, such as a smartphone, are described. In one embodiment, the wearable items automatically detect a removal of a first wearable item from a user's body and an attachment of a second wearable item to the user's body. Messages from the wearable items are transmitted to the electronic device to allow the electronic device to switch the active wearable item from the first wearable item to the second wearable item. The switch can occur while the electronic device is in a locked state, and the electronic device can synchronize the second wearable item with data received from the first wearable item. Other embodiments are also described.

The embodiments described herein relate to an accessory for a companion electronic device, such as a watch or fitness tracker for a smartphone.
Watches and fitness trackers can be paired, typically though Bluetooth wireless communication, with a companion device to provide health tracking functions and potentially other capabilities. For example, a Fitbit device or an Apple Watch can gather health data through one or more sensors and then transmit this health data to the companion device which can be a data processing system such as a smartphone or tablet computer or laptop computer, etc. An Apple Watch can also provide other functions such as notifications of messages, emails, voicemails, etc. and many other functions which can be provided by apps that execute on the watch.

This patent is subject to a terminal disclaimer.

Switching between watches or other accessories


A method of synthesizing catalyst doped ZnS nanostructures including preparing a silicon substrate by vacuum depositing a metal catalyst nanostructure on an ultrathin silicon oxide layer, doping a zinc sulfide (ZnS) nanostructure with a catalyst of the metal catalyst nanostructure including at least one of gold (Au), manganese (Mn), and tin (Sn), and modulating ZnS intrinsic defects by the concentration of the catalyst and the size of the ZnS and metal catalyst nanostructures, in which the catalyst is dissolved in a nanowire of the ZnS nanostructure during growth, the concentration of the catalyst in the nanowire is dependent on the size of the catalyst, and the doping is tuned by growth conditions.

In recent past, nanoparticles or quantum dots, nanowires, nanorods have become attractive because of the properties that are different from their bulk counterparts. Their unique characteristics may be attributed to quantum confinement effects, which may have led to band gap engineering. Zinc Sulfide (ZnS), a wide band gap semiconductor, has found various applications as optical phosphors, photonic crystals, UV sensors, photo-conducting switch, solar cells, field emitters, and light emitting materials. ZnS absorbs only UV radiation because of its large band gap, but its absorption and emission band may be altered by doping it with metal ions, such as manganese (Mn), nickel (Ni), copper (Cu), and lead (Pb). Furthermore, intrinsic defects, such as Zn and S electronic vacancies in ZnS nanostructures, may play a role in the visible emission. The amount of Zn and S vacancies has been reported to depend strongly on the growth and post growth processing conditions.
In general, ZnS in its Wurtzite phase may be more desirable than in its Sphalerite phase because of superior optical properties in its Wurtzite phase. ZnS nanowires and nanobelts have been demonstrated to have similar photoluminescence (PL) emission bands. Incorporation of metal ions actually offers an efficient radiative channel by introducing a band gap state, which may alter the optical properties of the host material. Thus, the choice and location of the metal ion in the host lattice is very important in defining the radiative recombination pathway.
Photoluminescence and electroluminescence properties of Mn doped ZnS have been extensively studied. ZnS has attained unusual attention in electroluminescent devices, lasers, and flat panel displays when doped with Mn. Doping of Mn in ZnS crystal has been reported to reduce the probability of nonradiative recombinations, and to make the Mn doped ZnS to phosphor in the range 590 nm to 620 nm due to radiative recombinations between the Mn d-states. Coupling of sp states of nanocrystalline ZnS and 3d states of Mn may result in faster transfer of electron from ZnS band to Mn 3d states in 5 orders of magnitude. The PL spectrums of undoped ZnS nanobelts and Mn doped ZnS nanobelts have shown some emission bands at 440 nm and 540 nm, bands of which may be assigned to defects produced by Sulfur (S) and Zn electron vacancies, respectively, while the emission band observed at 590 nm Mn doped ZnS may be attributed to Mn d-d state transition. In the case of Cu-doped ZnS nanorods, green emission may be attributed to elemental S species present on a nanorod surface, and orange emission may be associated with recombination of electron at deep defect levels of Cu introduced states. Surface defect states are well known to be responsible for the blue emission at 410 nm, green emission at 540 nm originated from Zn vacancy states, or interstitial states.
Recently, the role of the intrinsic defects like Zn and S interstitials and vacancies on the visible luminescence from the ZnS nanostructure has been studied. The interstitials and vacancies created by both Zn and S may lead to strong luminescence in the band gap with varying decay times. The magnitude of defects may be controlled by annealing the nanostructures in an inert atmosphere, in which the annealing may affect the optical properties.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it 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.

Method for the synthesis of catalyst doped ZnS nanostructures

COMSATS Institute of Information Technology


An information processing apparatus includes: a memory that stores a target region image generated in the past that indicates a distance to a target object; and a processor coupled to the memory and configured to calculate a hand region within a range image obtained after the target region image has been generated, the range image indicating a distance to a hand and the target object, detect a movement of the target object, when a movement of the target object is not detected, generate a complemented image by complementing, using the target region image, the portion that corresponds to the hand region within the image from which the hand region has been deleted, update the target region image with the complemented image, and, when a movement of the target object has been detected, update the target region image with the image from which the hand region has been deleted.

Recently, techniques such as Augmented Reality (AR) and the Internet of Things (IoT) have been actively developed for linking the actual world and virtual information so as to achieve interactions. Interface apparatuses have been developed that identify the positions of a real object and a finger using a range sensor so as to enable an interaction between the real object and the finger. The interaction between the real object and the finger means actions such as touching the object or tracing fingers over the object.
A technique is also known for decreasing erroneous detections of operations or designated positions based on a user's hand operations in an environment where objects included in an input image are moved by the user's operations (see, for example, patent document 1).
For an interaction between an actual object (target object) and a finger, the target object is installed to perform a calibration process in advance. The calibration process is a process of placing a target object and of registering the position of the object, e.g., the distance between a range sensor and the target object, with the hand removed from the shooting range of the range sensor. The calibration process is also performed when the target object has moved.
Performing the calibration process every time a target object is installed or moved is very burdensome and leads to a problem of usability loss.    Patent Document 1: Japanese Laid-open Patent Publication No. 2015-22624    Patent Document 2: Japanese Laid-open Patent Publication No. 2001-282456    Non-Patent document 1: Wataru WATANABE and three others, "Development and Improved Operability of Projection Plane Touch UI Based on Projector and Depth Camera", 21st Image Sensing Symposium, June 2015

Information processing apparatus, interaction method, and recording medium


The present disclosure provides a laterally diffused metal-oxide-semiconductor (LDMOS) device. The LDMOS device includes a plurality of fin structures formed on a substrate including a first device region, a second device region, and an isolation region sandwiched between the two regions. An opening is formed in the fin structures in the isolation region. The LDMOS device further includes an isolation layer formed in the opening and covering the sidewall of the opening formed by a portion of each fin structure in the first device region. The isolation layer exposes top surfaces of the plurality of fin structures. Moreover, the LDMOS device also includes a gate structure formed across each fin structure in the first device region. The gate structure covers a portion of the sidewall and the top surfaces of the fin structure formed in the first device region and also covers the top surface of the isolation layer.

With rapid development of semiconductor fabrication technology, semiconductor devices are advanced in a direction of having higher component density, higher integration level, and better performance.
Laterally diffused metal-oxide-semiconductor (LDMOS) device is a power device with a double-diffused structure. The LDMOS device is typically fabricated by performing two ion implantation processes onto a substrate. For example, one implantation process may introduce arsenic (As) ions with a relatively high concentration into the substrate, while the other implantation process may introduce boron (B) ions with a relatively low concentration. After performing the two ion implantation processes, a high temperature annealing process is performed. During the high temperature annealing process, boron ions often diffuse quicker than arsenic ions. Therefore, along a lateral direction under the gate electrode, boron ions may diffuse further than arsenic ions, and thus form a channel with a concentration gradient. The length of the channel is determined by the difference between the diffusion lengths of the two types of ions along the lateral direction. Moreover, in order to increase the breakdown voltage, a drift region may be formed between the source region and the drain region of the device.
The drift region in LDMOS devices is the key to the design of the devices. The impurity concentration in the drift region is relatively low. When an LDMOS device receives a high voltage, the device may be able to sustain such a high voltage because of the high resistance of the drift region. Moreover, LDMOS devices demonstrate advantages including high gain, high reliability, etc. and may also show desired process compatibility with existing CMOS devices, and thus LDMOS devices are widely used in various fields.
However, the gate dielectric layer in existing LDMOS devices may be easily broken down. The disclosed semiconductor structures and fabrication methods thereof are directed to solve one or more problems set forth above and other problems in the art.

Laterally diffused metal-oxide-semiconductor devices and fabrication methods thereof

SEMICONDUCTOR MANUFACTURING INTERNATIONAL (SHANGHAI) CORPORATION

SEMICONDUCTOR MANUFACTURING INTERNATIONAL (BEIJING) CORPORATION


The object-side surface of a negative lens element closest to the object side within a first lens group includes a paraxial convex surface and a peripheral surface having a curvature less than that of the paraxial surface. The image-side surface of a last lens element of a second lens group includes a paraxial concave surface and a peripheral surface having an inflection point changing from positive to negative values. 0.10<La/TL<0.31, and 0.35<Bh<0.70 are satisfied; La: distance from the object-side surface of the negative lens element, closest to the object side, to an axial light-bundle restriction diaphragm closest to the object side; TL: distance from the object-side surface of this negative lens element to an imaging surface; Bh: height to an inflection point on the image side of the lens element closest to the image side divided by the effective radius thereof.

1. Field of the Invention
The present disclosure relates to an imaging optical system (wide-angle imaging lens system) that can be installed in an imaging apparatus such as, e.g., an on-board camera, a surveillance camera, and a camera in a portable terminal.
2. Description of Related Art
In recent years, devices that use a camera mounted on or in a motor vehicle to recognize surrounding objects, apply an automatic brake if a collision is anticipated, or to follow a vehicle traveling in front of the motor vehicle have become commonplace. There is a demand for such on-board cameras to not only have surveillance capabilities in front of the vehicle, but also surveillance capabilities for a wider range in forward diagonal directions in which sidewalks (footpaths) and intersections can be captured. A wide-angle lens system is used to carry out surveillance over a wider range; however, a typical (conventional) wide-angle lens system has a small magnification, which risks a reduction in object recognition precision. In particular, since a high detection precision is demanded at a central area in which a vehicle in front or an on-coming vehicle is located, it is preferable to obtain a large image. Therefore, there is a demand for the on-board camera to be capable of capturing (shooting) a wide range/area while capturing a large image at the central area of the image.
Japanese Unexamined Patent Publication No. 2004-354572 (herein "Patent Publication 1") discloses an imaging apparatus provided with a compact image input optical system that employs a projection method that enlarges the object image at the central area of the picture screen and does not need a complex arrangement or configuration such as a zoom optical system or a superwide angle lens system. Japanese Unexamined Patent Publication No. 2005-10521 (herein "Patent Publication 2") discloses an imaging apparatus provided with a large-aperture, compact, high quality imaging lens that utilizes the advantages of the fovea lens.
However, in the imaging apparatuses disclosed in Patent Publications 1 and 2, the diameter of the first lens provided closest to the object side is large, and the degree of retroflection on the peripheral profile on the surface on the object side of the first lens is large. Since the on-board camera (optical system) is typically provided at the top of the front windscreen of the motor vehicle at a position very close to the inner side of the front windshield (windscreen), if the diameter and the retroflection of the first lens are large, the lens unit increases in size and thereby obstructs the view of the driver of the motor vehicle and clutters the spatial interior of the motor vehicle.


High-dielectric-constant (k) materials and electrical devices implementing the high-k materials are provided herein. According to some embodiments, an electrical device includes a substrate and a crystalline-oxide-containing composition. The crystalline-oxide-containing composition can be disposed on a surface of the substrate. Within the crystalline-oxide-containing composition, oxide anions can form at least one of a substantially linear orientation or a substantially planar orientation. A plurality of these substantially linear orientations of oxide anions or substantially planar orientations of oxide anions can be oriented substantially perpendicular or substantially normal to the surface of the substrate such that the oxide-containing composition has a dielectric constant greater than about 3.9 in a direction substantially normal to the surface of the substrate. Other embodiments are also claimed and described.

Silicon dioxide (SiO2) has been used as the primary gate-dielectric material in field effect devices for almost 50 years. However, it is projected, for example, that metal oxide semiconductor (MOS) field effect transistors (FETs) will have gate lengths of less than about 10 nanometers (nm) and will require equivalent oxide thicknesses of SiO2 of about 0.5 nm or less than about 3 atomic layers. The minimum equivalent oxide thickness of SiO2 has been estimated to be about 0.7 nm. Such thin oxide layers represent a fundamental challenge to the historic steady reduction in integrated circuit sizes that have characterized the very successful semiconductor industry. Specifically, at these small thicknesses, the amount of current leakage, which is caused by direct tunneling of charge carriers through the thin oxide layer, may be too high.
Since the capacitance of the oxide layer is proportional to the dielectric constant and inversely proportional to its thickness, using a higher dielectric constant material allows a proportionally greater thickness to be used. High dielectric-constant (high-k) materials, or materials having a dielectric constant greater than that of SiO2 (i.e., 3.9), are clearly needed for silicon (Si) based MOS technologies since the above equivalent oxide thickness are too small to be practically implemented with SiO2. High-k insulators, or high-k dielectrics, are needed to compensate for gate current increases that result from the scaling down of gate oxide thicknesses. Such dielectrics are even more important for low-power circuits where gate leakage power consumption represents a fundamental limitation.
One approach to implementing high-k dielectrics is to use oxides of hafnium (e.g., HfO2), tantalum (e.g., Ta2O5), lanthanum (e.g., La2O3), and zirconium (e.g., ZrO2) or nitrides of hafnium (e.g., HfSiON) or tantalum (e.g., TaN). The dielectric constants of these amorphous materials are about 5 to about 20. These materials in their current implementation, however, have reliability issues associated with them. Specifically, charge trapping effects can cause transistor degradation, and channel carrier mobility and transconductance may be degraded. Stacks or laminates of these oxides may provide improved performance. However, since stacked layers may be represented as capacitors in series, the equivalent oxide thickness will never be less than that of the lowest dielectric constant layer.
Accordingly, there is a need for improved high-k materials, high-k electrical devices manufactured therefrom, and associated fabrication methods that exhibit a suitably small effective oxide thickness as well as good stability and reliability on the substrate. It is to the provision of such materials, devices, and methods that the various embodiments of the present invention are directed.

High dielectric constant insulators and associated fabrication methods


The present invention relates to a system and method of securing a printer. The system includes a printer, having a nontransitory storage medium, configured to: store a password encrypted with a first encryption scheme; re-encrypt the stored password with a second encryption scheme upon a predetermined interval/event; receive a data stream from a host computer; determine whether the received data stream contains the password encrypted with the second encryption scheme; and print a document upon determining that the data stream contains the password encrypted with the second encryption scheme.

Security documents are used across a diverse marketplace to deter fraud, counterfeiting and theft. In most cases, the security documents are pre-printed on media. The pre-printed media must be stored in a secure location so that counterfeiters and thieves are not able to obtain the secure media which would allow them to freely print fraudulent documents.
There are printers that can print these secure patterns on demand on standard media. In brief, security printing relates to the practice of manufacturing media substrate with certain security indicia/features to prevent forgery and counterfeiting of items such as passports, checks, and prescription pads. As should be understood by those of ordinary skill in the art, security printing can include, for example, the inclusion of watermarks, UV coatings, security fibers, microprinting, holograms, phosphorescent inks, and pantographs (e.g., "void") etc. in the manufacture of the media substrate. The advantage of these "security printers" is that standard media does not have to be secured from theft as the secure documents can be created on demand. However, the printer must be set up with features/methods that disable printing of these secure patterns if a thief were to steal the printer.
Security printers, being capable of producing a wide variety of official documents, are targets for counterfeiters, desiring the ability to print official documents. Accordingly, there is a need in the art to secure such printers against unauthorized users.

System and method for securing a device with a dynamically encrypted password


A method of display modification in a client server web system, comprising, intercepting, by a web intermediary, a response to a client request, sent by a server in response to the request, the response including client side active content adapted to execute at a browsing software on a client computer; replacing at least one display-related code section in said response by a wrapper section that includes code for modification of at least one display element and code for executing the original display-related code section; and executing said wrapper section as client side active content at said client to generate a display, modified from a display that would have been generated by executing the response.

Information on the internet is disseminated to many different users. Often, the users differ in their native language. Also, the computer display abilities of one user may be different from those of another user. The information is typically extracted from a database in response to a request and sometimes generated in response to the request. The problem is that the different users will generally desire to see the information in their native language.
One possible solution is to modify the data source (e.g., a web-server) so that it supports the needs of the many different users. This may be expensive and may, in some cases, be an impossible task, as different users have different needs.
Another possibility is to change the user's computer (e.g., software thereon), for example providing a special plug-in or browser to display the data as desired. This option is typically not practical as users are adverse to installing software on their computers. The data may be unavailable if no special software is used. Also, such software may be required to work with a wide range of browser types, which may be a Herculean undertaking.
Another possibility is to provide a web-intermediary in the form of a proxy which detects and replaces strings in one language by strings in another language (thus effecting a translation). However, such a proxy does not solve the problem for strings which are generated by client side active code and cannot be detected in the material sent by the web server. In addition, it may be difficult to distinguish between strings which should be changed (e.g., phrases to be printed) and strings that are actually parts of commands and should therefore not be replaced.

NetMask (El-Mar) Internet Technologies Ltd.


A semiconductor device prepared by forming a silicon substrate of one conductor type having a surface of the (100) crystal plane, opening a rectangular window having sides parallel to the <100> crystal axis, etching the interior of the rectangular window with an anisotropic etching solution to form a dent, removing the oxide film and growing an epitaxial layer of a conductor type opposite to that of the substrate on the entire surface of the substrate, and masking the dent with an oxide film and etching the epitaxial layer with an anisotropic etching solution to flatten the surface of the epitaxial layer, and a method for making this semiconductor device.

1. Field of the Invention
The present invention relates to a semiconductor device and a method for the preparation thereof. Particularly, the invention relates to a high-voltage semiconductor integrated circuit and a method for the preparation thereof. More particularly, the invention relates to a semiconductor device comprising a substrate and, formed thereon, an epitaxially grown layer having a flat surface but being partially different in the thickness, and a method for the preparation thereof.
2. Description of the Prior Art
A conventional semiconductor device is illustrated in FIG. 1. In the conventional integrated circuit, isolation is accomplished by applying a reverse bias to a PN junction and utilizing reverse characteristics of a PN diode. Accordingly, the upper limit of the breakdown voltage of the isolation-collector junction is controlled by the breakdown voltage of the PN junction. In FIG. 1, reference numeral 11 represents a semiconductor substrate of the P or N conductor type, reference numeral 12 represents a highly impurity-doped buried layer of the N or P conductor type, and reference numeral 13 represents a highly impurity-doped buried layer of the P or N conductor type. Reference numeral 14 represents an epitaxially grown semiconductor layer of the N or P type having a thickness t.sub.EP, and reference numeral 15 represents a highly doped P or N type diffusion layer for isolation. Reference numeral 16 represents a silicon oxide film (SiO.sub.2 film). In other FIGS. described hereinafter, these reference numerals represent the same elements. In general, it is considered that the following methods are effective for increasing the breakdown voltage of the planar type PN junction:
(1) To further reduce the impurity concentration in the lowly impurity doped region.
(2) To increase the diffusion depth in the diffusion layer.
In general, the diffusion layer 15 expands substantially in the circular form as seen from the sectional view of FIG. 2. Accordingly, if a reverse bias is applied to this PN junction, the intensity of the electric field in this circular portion is increased, and the breakdown voltage is determined by this circular portion. As the diffusion depth of the diffusion layer is increased, the concentration of the electric field in this circular portion is weakened, and hence, the breakdown voltage is improved.
(3) To form external elements such as a field plate FP and a field limiting ring FLR around the diffusion layer 32 as shown in FIG. 3.
Problems caused when the foregoing means are applied to the conventional integrated circuit having a structure as shown in FIG. 1 will now be discussed.
The resistivity and thickness of the epitaxially grown N type layer are determined by the breakdown voltage of a transistor formed therein. The voltage BV.sub.CEO between the collector and emitter of the transistor is determined from a maximum voltage V.sub.CCMAX applied to the circuit (in general, the relation of V.sub.CCMAX =BV.sub.CEO is established), and the breakdown voltage BV.sub.CBO between the base and collector is determined from the current gain h.sub.FE and BV.sub.CEO (in general, the relation of ##EQU1## is established). Since BV.sub.CBO is the breakdown voltage of the PN junction between the base and collector, the minimum resistivity .rho..sub.EPMIN of the epitaxial layer is determined from the value of BV.sub.CBO. In general, a value .rho..sub.EP higher than .rho..sub.EPMIN is set appropriately from the viewpoint of the deviation of the diffusion depth caused in the preparation steps and the influences of the surface.
When the value .rho..sub.EP is thus set, the thickness t.sub.EP of the epitaxial layer is then determined. The minimum value t.sub.EPMIN of this thickness corresponds to the width of a depletion layer which extends from the base-collector junction toward the epitaxial layer when a maximum voltage is applied in the state where the resistivity is at the maximum value .rho..sub.EPMAX, and the thickness t.sub.EP is determined in view of the deviation caused in the preparation steps.
From the foregoing illustration, it will readily be understood that in order to increase the breakdown voltage, it is necessary to heighten .rho..sub.EP and increase t.sub.EP. From FIG. 1, it will readily be understood that if t.sub.EP is increased, it is necessary to increase the diffusion depth of the diffusion layer 15 of the P.sup.+ type for isolation. When the diffusion depth is increased, expansion of the diffusion layer 15 for isolation in the lateral direction is increased as shown in FIG. 2 and the occupying area of the diffusion layer is increased. For example, in case of an integrated circuit having a breakdown voltage of 150 V, t.sub.EP is about 35 .mu.m and .rho..sub.EP is about 15 .OMEGA.-cm, and even if isolation is accomplished by the diffusion layer and buried layer as shown in FIG. 2, the diffusion depth x.sub.1 of the layer 15 is about 25 .mu.m and an additional area corresponding to this value becomes necessary for isolation. Further, as a result of increase of the .rho. .sub.EP value, the expansion x.sub.2 of the depletion layer 21 shown in FIG. 2 becomes about 30 .mu.m, and therefore, an additional area corresponding to 30 to 40 .mu.m is necessary for the isolation region as compared with a low breakdown voltage integrated circuit.
When a high breakdown voltage integrated circuit is actually prepared, in general, the number of isolation islands on which elements actually requiring a high breakdown voltage are formed is usually small. Also the area necessary for such low breakdown voltage isolation is substantially the same as described above, and such increase of the area annuls the significance of an integrated circuit from the economical viewpoint.
The problem concerning low breakdown voltage portions is that the series resistance r.sub.SC of the collector of the transistor is greatly increased because .rho..sub.EP is heightened and the thickness t.sub.EP is increased. For example, the emitter area of a transistor customarily used for a low breakdown voltage integrated circuit is about 20 .mu.m.times.20 .mu.m, and .rho..sub.EP is 1.5.OMEGA.-cm and t.sub.EP is about 10 .mu.m. If it is intended to realize a transistor having the same r.sub.SC value under the above-mentioned conditions of .rho..sub.EP =15.OMEGA.-cm and t.sub.EP .perspectiveto.35 .mu.m, it is necessary to increase the emitter area. Namely, an emitter area of 120 .mu.m.times.120 .mu.m, 35 times the above emitter area, becomes necessary. Accordingly, realization of an integrated circuit becomes difficult from the economic viewpoint.
As means for overcoming the foregoing disadvantages, there has been proposed a structure shown in the sectional view of FIG. 4 (see Japanese Patent Publication No. 48955/1976). This structure is characterized in that the thickness of the epitaxial layer 14 differs in a high breakdown voltage element-forming portion 14-1 and a low breakdown voltage element-forming portion 14-2 and the diffusion layer 15 for isolation can be formed in the thin portion. In this structure, since a low breakdown voltage transistor is formed in the thin portion of the epitaxial layer, the emitter area necessary for maintaining r.sub.SC at the same level as in a low breakdown voltage integrated circuit should naturally be decreased as compared with the emitter area in the structure shown in FIG. 1.
As one method for preparing a semiconductor integrated structure as shown in FIG. 4, there can be mentioned a method comprising the steps (1) etching a predetermined region of a substrate to form a substrate having a dent 41, (2) forming a semiconductor layer only on the dent of the substrate by selective epitaxial growth and (3) forming a semiconductor layer on the entire surface by second epitaxial growth, whereby an integrated circuit comprising a substrate and, formed thereon, an epitaxially grown layer having a flat surface but differing in the thickness can be prepared (see Japanese Patent Publication No. 48955/1976).
According to this method, however, the epitaxial growth should be conducted two times and procedures of the selective epitaxial growth at the step (2) is complicated. Therefore, the method as a whole is not simple.
As another method for preparing a structure as shown in FIG. 4, there can be mentioned a method comprising (1) etching a predetermined region of a substrate 11 to form a substrate having a dent 41, (2) forming a semiconductor layer on the entire surface of the substrate inclusive of the dent by epitaxial growth, and (3) forming a mask on the bottom face of a secondary dent formed on the epitaxially grown layer by transfer of the dent 41 of the substrate and flattening the surface of the epitaxially grown layer by etching (see Japanese Patent Application Laid-Open Specifications No. 43369/77 and No. 69587/77). However, since in conventional semiconductor devices, a dent of a rectangular shape having sides parallel to the crystal axis <110> is formed, according to this method, in many cases, the surface of the epitaxially grown layer is not sufficiently flattened and convexities are readily formed around the mask of the secondary dent. Accordingly, etching or mechanical polishing should be further conducted for flattening the surface. Therefore, the method as a whole is complicated.

Junction isolated IC with thick EPI portion having sides at least 20 degrees from (110) orientations


An internal shoe drum brake having a generally C-shaped shoe return spring of which an intermediate portion is retained on the backplate and respective end portions respectively engage brake shoes. The intermediate portion of the spring is retained by a retention device secured to the brake backplate and has opposed tongues embracing a portion of the spring in such a manner as to retain the spring relative to the backplate in directions generally parallel to the latter. The retention device also retains the spring in a direction perpendicular to the backplate and may be associated with or embody a mounting device for an electrical component.

1. Field of the Invention
This invention relates to an internal shoe drum brake, primarily for a motor vehicle, and having a pair of brake shoes mounted on a backplate and separable by an actuator into braking engagement with a rotatable brake drum against the action of resilient return means in the form of a generally C-shaped element of which an intermediate portion is retained on the backplate by retention means fast with the latter, and of which portions spaced longitudinally from the intermediate portion cooperate with the shoes in a manner such as to produce an inward shoe return force.
2. Description of Related Art
It has been proposed to retain the spring in a brake of this kind by providing one or more pairs of integral lugs in the backplate which define slots arranged in a plane generally perpendicular to the backplate so as to retain the spring in a direction generally parallel to the backplate. In addition, the spring is usually retained in a direction perpendicular to the backplate by way of a separate retaining device secured to the backplate. This slotted arrangement tends to create stress points in the backplate which can give rise to cracking thereof in use and one object of the invention is to provide a spring retention means which is less prone to this problem.


The present invention is a high ORequency, high efficiency start and quick restart system including a lamp. It includes hook ups for connecting and applying a power input to circuitry; a switch for switching a lamp on and off, and is connected to control power; auto-ranging voltage control circuitry; and a three stage power factor correction microchip controller. The microchip controller is a Bi-CMOS microchip. There is also a feedback current sensor; a power factor correction regulator; bulb status feedback; a bulb voltage controller; a conditioning filter; a half-bridge; a DC output inverter; and, output and connection for, as well as, a metal-halide discharge lamp.

1. Field of the Invention
The present invention is directed to a system for quick restart of metal halide high pressure discharge lamps. The system is a high frequency, high efficiency system which includes ballast features and utilizes a three stage power factor correction microchip in a unique circuit to achieve a diverse, superior device.
2. Information Disclosure Statement
The following patents represent the state of the art in ballast and lamp lighting systems:
U.S. Pat. No. 5,929,563 to Andreas Genz describes a metal-halide high-pressure discharge lamp with a discharge vessel and two electrodes which has an inside discharge vessel and ionizable filling, which contains yttrium (Y) in addition to inert gas, mercury, halogen, thallium (Tl), hafnium (Hf), whereby hafnium can be replaced wholly or partially by zirconium (Zr), dysprosium (Dy) and/or gadolinium (Gd) as well as, optionally, cesium (Cs). Preferably, the previously conventional quantity of the rare-earth metal is partially replaced by a molar equivalent quantity of yttrium. With this filling system, a relatively small tendency toward devitrification is obtained even with high specific arc powers of more than 120 W per mm of arc length or with high wall loads. Thus, the filling quantity of cesium can be clearly reduced relative to a comparable filling without yttrium, whereby an increase in the light flux and particularly in the brightness can be achieved.
U.S. Pat. No. 5,900,701 to Hansraj Guhilot et al. describes a lighting inverter which provides voltage and current to a gas discharge lamp in general and a metal halide lamp in particular with a novel power factor controller. The power factor controller step down converter having the device stresses of a buck converter, continuous current at its input like a CUK converter, a high power factor, low input current distortion and high efficiency. The inverter consists of two cyclically rotated CUK switching cells connected in a half bridge configuration and operated alternately. The inverter is further optimized by using integrated magnetics and a shared energy transfer capacitor. The AC voltage output from the inverter is regulated by varying its frequency. A ballast filter is coupled to the regulated output of the inverter. The ballast filter is formed by a series circuit of a ballast capacitor and a ballast inductor. The lamp is preferably connected across the inductor to minimize the acoustic arc resonance. The values of the capacitor and the inductor are chosen so as to satisfy the firing requirements of the HID lamps. A plurality of lamps are connected by connecting the multiple lamps with the ballast filters to the secondary of the inverter transformer. Almost unity power factor is maintained at the line input as well as the lamp output.
U.S. Pat. No. 5,323,090 to Guy J. Lestician is directed to an electronic ballast system including one or more gas discharge lamps which have two unconnected single electrodes each. The system is comprised of a housing unit with electronic circuitry and related components and the lamps. The system accepts a.c. power and rectifies it into various low d.c. voltages to power the electronic circuitry, and to one or more high d.c. voltages to supply power for the lamps. Both the low d.c. voltages and the high d.c. voltages can be supplied directly, eliminating the need to rectify a.c. power. The device switches a d.c. voltage such that a high frequency signal is generated. Because of the choice of output transformers matched to the high frequency (about 38 kHz) and the ability to change frequency slightly to achieve proper current, the device can accept various lamp sizes without modification. The ballast can also dim the lamps by increasing the frequency. The device can be remotely controlled. Because no filaments are used, lamp life is greatly extended.
U.S. Pat. No. 5,287,040 to Guy J. Lestician is directed to an electronic ballast device for the control of gas discharge lamps. The device is comprised of a housing unit with electronic circuitry and related components. The device accepts a.c. power and rectifies it into various low d.c. voltages to power the electronic circuitry, and to one or more high d.c. voltages to supply power for the lamps. Both the low d.c. voltages and the high d.c. voltages can be supplied directly, eliminating the need to rectify a.c. power. The device switches a d.c. voltage such that a high frequency signal is generated. Because of the choice of output transformers matched to the high frequency (about 38 kHz) and the ability to change frequency slightly to achieve proper current, the device can accept various lamp sizes without modification. The ballast can also dim the lamps by increasing the frequency. The device can be remotely controlled.
U.S. Pat. No. 5,105,127 to Georges Lavaud et al. describes a dimming device, with a brightness dimming ratio of 1 to 1000, for a fluorescent lamp used for the backlighting of a liquid crystal screen which comprises a periodic signal generator for delivering rectangular pulses with an adjustable duty cycle. The pulses are synchronized with the image synchronizing signal of the liquid crystal screen. An alternating voltage generator provides power to the lamp only during the pulses. The decrease in tube efficiency for very short pulses allows the required dimming intensity to be achieved without image flickering.
U.S. Pat. No. 5,039,920 to Jerome Zonis describes a gas-filled tube which is operated by application of a powered electrical signal which stimulates the tube at or near its maximum efficiency region for lumens/watt output; the signal may generally stimulate the tube at a frequency between about 20 KHz and about 100 KHz with an on-to-off duty cycle of greater than one-to-one. Without limiting the generality of the invention, formation of the disclosed powered electrical signal is performed using an electrical circuit comprising a feedback transformer having primary and secondary coils, a feedback coil, and a bias coil, operatively connected to a feedback transistor and to a plurality of gas-filled tubes connected in parallel.
U.S. Pat. No. 4,937,470 to Kenneth T. Zeiler describes a gate driver circuit which is provided for push-pull power transistors. Inverse square wave signals are provided to each of the driver circuits for activating the power transistors. The combination of an inductor and diodes provides a delay for activating the corresponding power transistor at a positive transition of the control signal, but do not have a significant delay at the negative transition. This provides protection to prevent the power transistors from being activated concurrently while having lower power loss at high drive frequencies. The control terminal for each power transistor is connected to a voltage clamping circuit to prevent the negative transition from exceeding a predetermined limit.
U.S. Pat. No. 4,876,485 to Leslie Z. Fox describes an improved ballast that operates an ionic conduction lamp such as a conventional phosphor coated fluorescent lamp. The ballast comprises an ac/dc converter that converts an a-c power signal to a d-c power signal that drives a transistor tuned-collector oscillator. The oscillator is comprised of a high-frequency wave-shape generator that in combination with a resonant tank circuit produces a high-frequency signal that is equivalent to the resonant ionic frequency of the phosphor. When the lamp is subjected to the high frequency, the phosphor is excited which causes a molecular movement that allows the lamp to fluoresce and emit a fluorescent light. By using this lighting technique, the hot cathode of the lamp, which normally produces a thermionic emission, is used only as a frequency radiator. Therefore, if the cathode were to open, it would have no effect on the operation lamp. Thus, the useful life of the lamp is greatly increased.
U.S. Pat. No. 4,717,863 to Kenneth T. Zeilier describes a ballast circuit which is provided for the start-up and operation of gaseous discharge lamps. A power transformer connected to an inductive/capacitive tank circuit drives the lamps from its secondary windings. An oscillator circuit generates a frequency modulated square wave output signal to vary the frequency of the power supplied to the tank circuit. A photodetector feedback circuit senses the light output of the lamps and regulates the frequency of the oscillator output signal. The feedback circuit also may provide input from a remote sensor or from an external computer controller. The feedback and oscillator circuits produce a high-frequency signal for lamp start-up and a lower, variable frequency signal for operating the lamps over a range of light intensity. The tank circuit is tuned to provide a sinusoidal signal to the lamps at its lowest operating frequency, which provides the greatest power to the lamps. The ballast circuit may provide a momentary low-frequency, high power cycle to heat the lamp electrodes just prior to lamp start-up. Power to the lamps for start-up and dimming is reduced by increasing the frequency to the tank circuit, thereby minimizing erosion of the lamp electrodes caused by high voltage.
U.S. Pat. No. 4,392,087 to Zoltan Zansky describes a low cost high frequency electronic dimming ballast for gas discharge lamps is disclosed which eliminates the need for external primary inductance or choke coils by employing leakage inductance of the transformer. The system is usable with either fluorescent or high intensity discharge lamps and alternate embodiments employ the push-pull or half-bridge inverters. Necessary leakage inductance and tuning capacitance are both located on the secondary of the transformer. Special auxiliary windings or capacitors are used to maintain necessary filament heating voltage during dimming of fluorescent lamps. A clamping circuit or auxiliary tuned circuit may be provided to prevent component damage due to over-voltage and over-current if a lamp is removed during operation of the system.
Notwithstanding the prior art, the present invention is neither taught nor rendered obvious thereby.
The present invention is a high frequency, high efficiency quick restart system for lighting a particular type of bulb, including the bulb itself, namely, a metal halide high pressure lamp. It includes ballast features and other aspects and has a base or housing unit to support circuitry and related components, e.g. one or more circuit boards or a combination of circuit boards, supports or enclosures. The electronic circuitry and components mounted on the housing unit, includes: means for connecting and applying a power input to the circuitry; switch means for switching a lamp on and off, which switch means control is connected to control power to the circuitry; and auto-ranging voltage control circuitry and components, including an auto line supply filter and a line voltage correction EMI to provide an auto-ranging voltage intake/output capability. There is also a three stage power factor correction microchip controller. This microchip controller is a Bi-CMOS microchip. There is a feedback current sensor; a power factor correction regulator; a bulb status feedback means; a bulb voltage controller; a conditioning filter; a half-bridge; a DC output inverter; and, output means and connection for a lamp. The means for connecting and applying a power input to the circuitry may have connection and adaption for receiving AC current and/or DC current. The three stage power factor correction microchip controller includes power detection means for end-of-lamp-life detection, a current sensing PFC section based on continuous, peak or average current sensing, and a low start up current of less than about 1.0 milliamps. In preferred embodiments, the three stage power factor correction microchip contains a three frequency control sequencer. Some of the features of the power factor correction microchip include power detect for end-of-lamp life detection; low distortion, high efficiency continuous boost, peak or average current sensing PFC section; leading edge and trailing edge synchronization between PFC and ballast; one to one frequency operation between PFC and ballast; programmable start scenario for rapid/instant start lamps; triple frequency controls network for dimming or starting to handle various lamp sizes; programmable restart for lamp out condition to reduce ballast heating; internal over-temperature shutdown; PFC over-voltage comparator to eliminate output runaway due to load removal; and low start up current.
In most preferred embodiments the three stage power factor correction microchip includes corrections for each of the following functions:
(1) inverting input to a PFC error amplifier and OVP comparator input;
(2) PFC error amplifier output and compensation mode;
(3) sense inductor current and peak current sense point of PFC cycle-by-cycle current limit;
(4) output of current sense amplified;
(5) inverting input of lamp error amplifier to sense and regulate lamp arc current;
(6) output lamp current error transconductance amplifier to sense and regulate lamp arc current;
(7) external resistor to set oscillator to Fmax and Rx/Cx charging current;
(8) oscillator timing component to set start frequency;
(9) oscillator timing components;
(10) input for lamp-out detection and restart;
(11) resistance/capacitance to set timing for preheat and interrupt;
(12) timing set for preheat and for interrupt;
(13) integrated voltage for error amplifier output;
(14) analog ground;
(15) power ground;
(16) ballast MOSFET first drive/output;
(17) ballast MOSFET second drive/output;
(18) power factor MOSFET driver output;
(19) positive supply voltage; and,
(20) buffered output for specific voltage reference, e.g. 7.5 volt reference.
The power factor correction regulator in the present invention system is a power factor correction regulator with one MOSFET switching circuit, or two MOSFET switching circuits, and the DC output inverter is a DC output inverter with two MOSFET switching circuits, or four MOSFET switching circuits.
The lamp is a metal-halide high pressure discharge lamp with a discharge vessel and two electrodes. It contains an ionizable filling, which includes an inert gas, e.g. argon, mercury, a halogen, e.g. either iodine or bromine or a combination thereof, and metals which combine with these halogens to for metal halides, e.g. scandium, sodium, dysprosium, holmium and thulium rare earth metals. Preferably, the metal halides formed are in combination. Two typical combinations of halides used in these lamps are:
(1) scandium and sodium iodides, and, (2) dysprosium, holmium and thulium iodides. The present invention contemplates utilization of what are conventionally known as metal halide lamps in combination with the circuitry features described above and in greater detail below.
The system of the present invention not only illuminates these lamps well, but also provides for heretofore unachieved rapid restart capabilities.
In some preferred embodiments, the electronic circuitry and components switch means further includes dimmer circuitry and components.

High frequency, high efficiency electronic lighting system with metal halide lamp

Lower Smithfield Township, Monroe County


A scroll compressor 10 having a fixed scroll 18, an orbital scroll 70 and a drive 90 and 94 for moving the orbital scroll in a generally circular orbit. The scrolls 18 and 70 have end plates 24 and 72, with flat surfaces 26 and 76 and involute wraps 28 and 74. The wraps have inside flank surfaces 30 and 77, outside flank surfaces 32 and 78 and axial tips 34 and 80. A portion 164 of the axial tip 34 of the fixed scroll 18 adjacent the outside flank surface 32 is recessed from an adjacent portion of the axial tip that is adjacent to the inside flank surface 30. A portion 170 of the axial tip 80 of the orbital scroll 70 adjacent outside flank surface 78 has a surface in a plane that is recessed from an adjacent portion of the axial tip that is adjacent to the inside flank surface 77.

The scroll type fluid displacement apparatus has two scrolls. Each scroll includes an end plate and a spiral wrap. The wrap is attached to the end plate and includes two flank surfaces and an axial tip. The wrap which is found in many scroll type machines is an involute spiral. The two scrolls are positioned relative to each other so that the wraps and the end plates cooperate to form one or more fluid chambers. The scrolls are driven in an orbital path relative to each other to move the fluid in the chambers. If the orbital movement moves fluid from the central portion of the scrolls toward the radially outer edge, the fluid is generally being expanded. If the orbital movement moves fluid from the radially outer portion of the scrolls toward the central portion of the scrolls, the fluid is generally being compressed or pumped.
Two scrolls can be rotated about parallel axes that are displaced from each other to obtain the required orbital movement relative to each other. Relative orbital movement can also be obtained by holding one scroll in a fixed position and driving the other scroll in an orbital path.
Scroll type fluid displacement machines often employ scrolls that form at least one pair of fluid pockets. The fluid pockets are bound by flank surfaces of the wraps and by surfaces of the end plates. For these machines to efficiently compress, pump or expand fluids, the fluid pockets must be sealed to reduce fluid leaks. The flank surfaces of the wraps are smooth and accurately shaped so that contact between them will at least limit fluid leaks. The axial tips of the wraps and the surface of the end plates can also be accurately shaped to limit fluid leaks when the scrolls are at a uniform temperature.
During pumping, expansion or compression of fluids, the fluid temperature changes. The change in fluid temperature as the pressure changes in the fluid pockets changes the temperature of the scrolls. The temperature change generally results in the temperature at the center of the scrolls being higher than the temperature at the radially outer edges of the scrolls. This temperature variation across the scrolls results in variations in the axial height of the wraps due to thermal expansion and contraction. The variation and change in height of the wraps must be accommodated to prevent leakage of fluid between the axial tips of the wraps and the surfaces of the end plate. Axial expansion of the wraps can result in the axial tips of the wraps exerting sufficient force against the adjacent scroll end plate to cause excessive wear and frictional load.
Fluid leakage between the wrap flank surfaces of one scroll and the wrap flank surfaces of another scroll is controlled by contacts between the flank surfaces. The flanks of scroll wraps are accurately formed, their surfaces are smooth and may even have special coatings. The drive systems employed are designed to maintain contact between the flank surfaces during orbital movement of a pair of scrolls relative to each other without causing wrap damage.
Fluid leakage between the axial tips of the wraps and the surfaces of the end plates is controlled by axial tip seals. Axial tip seals have been used which are resilient or spring biased so that the seals accommodate thermal expansion and contraction of the wraps and remain in sealing contact with the surfaces of the end plates. Seals which are free to float in a tip seal groove have also been used. The fluids in the fluid pockets hold the floating seals in sealing contact with the surfaces of the end plates during operation.
Axial tip seals are held in a tip seal groove or groove sections in the axial tip of each scroll wrap. A tip seal groove can not extend all the way to the end of a wrap in the center portion of a scroll or to the radially outer end of a wrap. The ends of a groove need to be closed to retain the axial tip seal. It is also desirable to close the ends of a tip seal groove to prevent the tip seal groove from becoming a conduit for fluid leakage. The radially outer end of scroll wraps generally have less radial thickness. The radial thickness of the wraps can be reduced at the radially outer end because only the inner flank surface of the wrap has to be machined to make sealing contact with a flank surface on the adjacent scroll wrap. The force exerted on the flanks of scroll wraps by fluid in the fluid pockets is generally less at the radially outer end of the wraps than it is on the wrap flanks near the center of the scrolls. Reduction of wrap thickness at the radially outer end where less strength is required reduces scroll weight, reduces scroll diameter and reduces the weight of balance weights required to balance orbital movement.
Axial tip seals create a drag which resists sliding along the surfaces of the end plates. This drag increases the drive torque required, increases tip seal and end plate surface wear, can brake wraps from end plates and causes heating. Heating of the tip seals and the scrolls can shorten the life of fluid displacement apparatus. Contact between end plates and the axial tips of scroll wraps also creates a drag that increases drive torque, heat generation and wear. The greater the area of surface contact, the greater the drag force, but the sealing effect does not increase proportionately.
Lubrication is commonly employed to reduce drag. Lubricants also reduce wear, increase tip seal life and improve sealing. Under some circumstances a thin film of lubricant can increase drag due to the shear strength of thin oil films.

Scroll type machine with improved wrap radially outer tip


A method of judging the load distribution of a vehicle without providing a specific load sensor on a vehicle is characterized in that the load distribution by the every wheel of a vehicle or the load distribution by every axle is judged by comparing the result of comparing the calculation value of the rotational speeds of wheels in the predetermined two combinations of wheels with the result of comparing the calculation value of the rotational speeds of wheels in the fore-mentioned predetermined two combinations of wheels at a predetermined load when the vehicle is under brakeage.

The present invention relates to a method for judging load distribution by the every wheel of a vehicle or the load distribution by every axle and a device thereof, and a judgment program of the load distribution of a vehicle.
When the pressures of tires mounted on a vehicle are decreased, a fuel mileage is deteriorated and there is danger of provoking burst at high speed running. When a tire is deflated, the decrease in pressure is detected through utilizing the change of properties of tires such as the decrease of the dynamic load radii of tires and the change of resonance frequency.
For example, a conventional detecting device for the decreased tire pressure uses a principle that since the outer diameter of a tire (the dynamic load radius of a tire) is reduced more than that of a tire having normal inner pressure when the pressure of a specific tire of a vehicle is reduced, rotational angular velocity is increased as compared with other normal tires. For example, a method for detecting the decrease in inner pressure from the relative difference of the rotational angular velocities of tires uses a value obtained from following formula as a judging value;DEL={(F1+F4)/2−(F2+F3)/2}/{(F1+F2+F3+F4)/4}×100(%)(Japanese Unexamined Patent Publication No. 305011/1988). Herein, F1 to F4 are the rotational angular velocities of a front left tire, a front right tire, a rear left tire and a rear right tire, respectively.
However, since the fore-mentioned properties of tires are changed by the change of loads such as the number of passengers on board and the weight of a load, the change of a load is judged as the change of tire pressures in the case the change of a load cannot be distinguished from the change of tire pressures; therefore the decrease in pressure cannot be accurately judged.
When all of tire pressures are normal, the fore-mentioned judging value DEL is zero, but when deflation is generated for a wheel, the judging value is changed in accordance with the level of a dynamic load radius. When the decrease in pressure at which an alarm is to be issued to a driver is 30% deflation relative to the normal pressure, the judging value at 30% deflation is referred to as a threshold, and the alarm is issued when the judging value exceeds the threshold. However, the larger the load is, the smaller the decreased level of the dynamic load radius at deflation is; therefore the judging value at 30% deflation in the case of one person boarding is larger than the judging value at 30% deflation in the case of 5 persons boarding.
For example, the judging value at 30% deflation is to be 0.3 in the case of one person boarding and 0.25 in the case of 5 persons boarding. In this case, when an alarm is designed to be issued at 30% deflation in the case of 5 persons boarding, the threshold must be 0.25. However, when the threshold is 0.25, an alarm is issued at 25% deflation in the case of one person boarding (30×0.25÷0.3=25).
There are inventions described in Japanese Unexamined Patent Publication No. 23425/1999, Japanese Unexamined Patent Publication No. 189136/1999 and Japanese Unexamined Patent Publication No. 306093/2003 as a device for judging the load distribution. In Japanese Unexamined Patent Publication No. 23425/1999, a means of detecting resonance level is required. In Japanese Unexamined Patent Publication No. 189136/1999, a means of detecting brakeage force and a means of calculating the gradient μ of road surface are required. In Japanese Unexamined Patent Publication No. 306093/2003, a means of detecting acceleration and deceleration is required.
It is described in Japanese Unexamined Patent Publication No. 196791/1997 and Japanese Unexamined Patent Publication No. 115578/1998 that the information of the load distribution is utilized for detecting the decreased tire pressure. In Japanese Unexamined Patent Publication No. 196791/1997, a load is detected by using a suspension stroke sensor. In Japanese Unexamined Patent Publication No. 115578/1998, a load is detected by judging the change of resonance frequencies before and after opening or closing a door, a trunk or a fill opening as the change of a load, or using a suspension stroke sensor.
Further, it is described in Japanese Unexamined Patent Publication No. 2222/1997 that a ratio of the rotational speed of front wheels to the rotational speed of rear wheels is changed at brakeage and at no brakeage, but relation between the ratio of the rotational speed of front wheels to the rotational speed of rear wheels under brakeage and the load of a vehicle is not described.


An exercise device for supporting a barbell and weights thereon. The exercise device includes a pair of support members that are independently selectively engageable on a support beam. Each support member includes an elongated post with a first end positioned adjacent a floor surface and a second end having an adjustable clamp assembly for engaging the support beam. The clamp assembly suspends the post from the beam and is selectively engaged between a first clamping position and a second movable position. Each support post further includes an adjustable bar support assembly for retaining the barbell thereon. A leveling assembly may be provided on the first end of the post to orient the post at right angles to the floor and beam. The exercise device may further include a safety catch assembly mounted on each of the support members and one or more optional weight support assemblies for storing weights thereon.

1. Technical Field
This invention generally relates to exercise devices for performing squat type exercises with barbells. More particularly, the invention relates to a barbell support which extends adjacent the user's shoulders for supporting the barbell. Specifically, the invention relates to an adjustable suspended squat rack for supporting barbells thereon.
2. Background Information
The general field of this invention and some of the devices used to perform squatting exercises were discussed in U.S. Pat. No. 7,025,712, issued to the instant inventor on Apr. 11, 2006. In this patent, it was disclosed that squatting exercises are performed by athletes to build up and strengthen their leg muscles. Squats are typically performed by supporting free weights in the form of a barbell and disk weights, the barbell being disposed across the lifter's shoulders and gradually descending from a standing position to a squatting position. During squats the back of the lifter does not remain straight as the lifter descends, but rather the angle of the back off of vertical increases as the lifter descends.
Various types of exercise equipment have been devised to facilitate squatting exercises, the most common being a basic upright frame having a ground contacting base with a pair of upright members spaced a distance apart to support opposite end portions of the barbell on U-shaped barbell cradles at respective upper free ends thereof. The lifter places the barbell on the cradles and adds the desired disk weights to each end of the barbell. The weights are secured to the barbell against respective radial flanges using a pair of collars. The cradles and supported barbell with weights are disposed at a height which is approximately shoulder level for the average lifter. Some such exercise equipment have multiples pairs of cradles disposed at various heights or telescoping upright members permit adjustment to fit the particular shoulder height of various lifters.
Another problem encountered with such exercise equipment is that it is not easily portable. While this might not be a problem for health clubs and other gyms which use such equipment, it is typically undesirable for home gyms. While interest in exercise has expanded over the years, many members of the public have found that belonging to a health club is too expensive and time consuming due to commute times. This has increased the demand for smaller, less expensive apparatus that may be placed in the home. However, use of exercise equipment in the home poses a serious space problem for many potential owners of home gyms. Because such equipment must be quite sturdy and durable to support heavy weights and high forces required by lifters, such exercise equipment is usually very heavy and must be fixed to the floor. Hence, present exercise equipment is not very maneuverable and is, therefore, not well suited for residential or non-institutional use.
An example of such exercise equipment particularly designed for squatting exercises is the barbell storage and exercise rack disclosed in U.S. Pat. No. 4,306,715, issued to Sutherland on Dec. 22, 1981. This exercise rack includes a pair of cradles in which the barbells are laterally received and supported in a stored position. The cradles are adjustable in height to permit the lifter to remove and replace the barbells from a comfortable standing position. The exercise rack further includes a pair of safety side rails which are spaced apart a distance sufficient to permit the user to stand between the rails to perform squatting and other weight lifting exercises. The side rails are also adjustable in height so as to be disposed slightly below the lower position assumed by the barbells during the squats to prevent the barbells from inadvertently falling on the lifter if the weight slips or becomes too heavy to lift as exercise is conducted. The exercise rack takes up significant floor space, is likely relatively expensive to buy, and is not that easily portable.
Another example of exercise equipment suitable for squatting exercises is disclosed in U.S. Pat. No. 5,411,458 issued to Giust on May 2, 1995. This equipment comprises an angled track squat exercise apparatus. The exercise apparatus includes a horizontally disposed base frame which supports at opposite ends a vertically disposed foot plate frame and a weight rack frame carrying a plurality of weights. A track frame is supported on the base frame between the foot plate frame and the weight rack frame. The track frame includes a horizontal section and a section which is downwardly inclined from the horizontal section. A carriage is supported on the track frame which is firstly displaced upwardly along the inclined section, then horizontally along the horizontal section by the legs and feet of the lifter pushing against the foot plate frame. The selected one of the weights is lifted in the weight rack as the carriage is displaced by the lifter. The exercise apparatus again takes up significant floor space, is likely relative expensive to buy and is not that easily portable.
The aforementioned patent No. 7,025,712 to the instant inventor addressed a solution to the problems in this field of home gym equipment. The patent disclosed a squat rack for use in the home and which is designed to be mountable to an overhead support beam that extends between opposed walls. The squat rack is designed for use in a room, such as in a basement, where an I-beam extends between the opposed walls. Specifically, this device was designed to be suspended from the I-beam and includes a pair of barbell support frames. Each support frame includes a frame mount and a cradle that is adapted to retain one of the end portions of the lifting bar. The cradle of each support frame is generally J-shaped and includes an upper end portion, a lower hook and a central portion disposed therebetween. The J-shaped member is adjustably connected to a generally vertically-disposed surface of the frame mount. This surface includes a plurality of vertical positions thereon to facilitate use of the squat rack by persons of differing heights. The squat rack further included a pair of mounting assemblies, each of which comprises a clamp that is adapted to attached to a horizontally disposed flange which forms part of the overhead support beam. The clamps vertically secure the frame mount to one of the support frame and support beam such that the cradle is disposed in parallel relation below the beam to support the barbells at generally shoulder height of the person who will perform the squat-type exercise.
While this device works very well, it is essentially designed to be more or less permanently installed on the I-beam. The barbell and weights are supported a distance downwardly from the I-beam and above the floor by the cradles. The actual height is dictated by the position to which the J-hooks are adjusted. As such, the barbell and weights may become a hazard to persons moving through the room where this device is mounted, with that room typically being a basement area. If it is desired to store the device or to move it for some reason, the mounting flanges have to be disengaged from the I-beam and the device has to be reinstalled at the new location. All of this is time consuming and counterproductive in that the need for this breaking down and reinstalling of the equipment might cause the user to change their mind and avoid use of the equipment.
There is therefore a need in the art for a device that is suspendable from an I-beam but is easily and quickly moved from one end of the I-beam to the other while not compromising on safety of the device.


A locking zipper includes a zip retainer and a zip fastener for zipping two elongated engaging tracks locating alongside of each other. The zip retainer includes a retention base, and a locking head integrally extended from the retention base. The zip fastener includes a sliding base and a key-free locker which is integrally provided at the sliding base and is releasably engaged with the locking head. At a zipped position, the sliding base is slid to the retention base for zipping the engaging tracks with each other that the key-free locker is locked with the locking head to securely lock up the zip fastener with the zip retainer. At an unzipped position, the key-free locker is released from the locking head such that the sliding base is slid away from the retention base for unzipping the engaging tracks from each other.

1. Field of Invention
The present invention represents a locking zipper, and more particularly a zipper with a key-free locker and a locking head which are integrally provided at the zipper respectively.
2. Description of Related Arts
Travel is one of the most important activities for people in the modern society, for the purpose of either leisure or business. In order to keep the properties in the luggage secure, placing a lock on the zipper of the luggage, including backpack, or laptop bags, would be necessary.
Traditional luggage locks are usually placed externally on the zipper, by putting the hook-shape metal of the lock through the rings of the zippers on the luggage and then engaging the hook-shape metal with the main body of the lock to achieve the purpose of locking. The locks can be accessed either by keys or combination of dialed numbers. However, traditional luggage locks suffer from their own limitations.
An additional lock on the luggage may seem bulky especially on backpacks and laptop bags. Furthermore, for the locks opened by keys, the luggage owners have to carry an additional key, and once the key is lost, the luggage cannot be opened without damaging either the lock or even the luggage itself.
Some lock bodies are fixed on the luggage and the zippers are pressed into the lock bodies with combination of dialed numbers to achieve the locking purposes. Although the fixed lock on the luggage does not appear bulky, the zippers can only be placed at some fixed locations and cannot be freely moved on the engaging tracks in zipped position.


An electronic apparatus includes a display unit, a sensor, and a controller. The display unit includes a screen. The sensor is configured to detect a user operation with respect to the screen and output a signal corresponding to the user operation. The controller is configured to cause a data icon and an access authority editing icon for editing an access authority of data related to the data icon to be displayed on the screen, judge a user operation with respect to the access authority editing icon based on the signal from the sensor, and change a state of the access authority of the data related to the data icon according to the user operation.

The present disclosure relates to a technique used in, for example, an electronic apparatus that detects a user operation with respect to a screen and executes processing corresponding to the user operation.
In recent years, an electronic apparatus that detects a user operation with respect to a screen and executes processing corresponding to the user operation is widely known (see, for example, Japanese Patent Application Laid-open No. 2011-70525).
In such an electronic apparatus, a user touches (taps), drag-and-drops, or flicks a position on the screen at which a GUI (Graphical User Interface) such as an icon is displayed so as to make an input to the electronic apparatus. The method of making an input to a screen is widely adopted in various electronic apparatuses since the method enables intuitive operations to be made.

Electronic apparatus, program, and control method for displaying access authority for data files


A new variety of Streptocarpus plant is characterized by its pure white color. It has smaller flowers and is more floriferous as compared to commonly grown Streptocarpus. It also has long permanence and is generally nonfertile.

The present invention comprises a new and distinct cultivar of Streptocarpus X hybridus known by the varietal name of Selena. The new cultivar is a mutation brought about by the irradiation of a Streptocarpus known by the varietal name Hera (U.S. Plant Pat. No. 4,948 issued Nov. 16, 1982). The new cultivar is similar to Hera in respect of plant form and growth characteristics and is different from Hera in respect of color.
The new cultivar is generally characterized by its pure white color. It has smaller flowers and is more floriferous as compared to commonly grown Streptocarpus. It has long permanence and is generally nonfertile.
The new cultivar was discovered Oct. 28, 1981 in Vaihingen, Federal Republic of Germany; was first asexually reproduced by cuttings in Vaihingen, Federal Republic of Germany; and has been repeatedly asexually reproduced by cuttings at Oglevee Floral Company in Connellsville, Pa. It has been found to retain its distinctive characteristics through successive propagations.
The new cultivar, when grown in a greenhouse in Connellsville, Pa., has a response time of eight weeks from a well-rooted young plant in a 21/4 inch pot to a flowering plant in a 6 inch pot.

Distinct variety of Streptocarpus named Selena


An apparatus is described, comprising: a first power converter with real or artificial hysteresis; a second power converter with real or artificial hysteresis; and a control circuit configured to output a control signal dependent on a phase difference or frequency difference between the first and second power converters; wherein the apparatus is configured such that a magnitude of hysteresis of at least one of said first and second power converters is controlled by said control signal.

It can be advantageous to operate two buck converters in multi-phase configuration. When run at the same frequency and with opposite phase, the resulting output current ripple is significantly reduced. The input current ripple may also be significantly reduced.
Hysteretic power converters are widely used for Solid State Lighting (SSL) applications, for example in cars. Many SSL applications require a low current ripple. However, hysteretic converters have no defined frequency and therefore are not used in multi-phase configurations. Instead, large filter capacitors are used to achieve a low ripple current. In LED matrix applications, the output voltage changes frequently with the number of shorted LEDs, causing the switching frequency of the hysteretic converter to vary frequently and over a wide range. This makes filtering more complicated and expensive.
Throughout this disclosure, the term 'hysteretic power converter' includes both power converters with real hysteresis and power converters with artificial hysteresis. An example of a hysteretic power converter with artificial hysteresis is the median converter which used controlled time delays to emulate hysteresis.

Apparatus comprising multiple power converters with real or artifical hysteresis


A vacuum ultraviolet light source for generating a pulse discharge in a low pressure gas and extracting ultraviolet light from a plasma created in that discharge, is disclosed which comprises a discharge space P, a plate-like anode located in the discharge space, a plurality of hollow cathodes located in the discharge space in an opposed, spaced-apart relation to the anode, auxiliary electrodes provided in an inside space of the hollow cathode in a state shielded from the hollow cathode, means which, while maintaining a pressure in the discharge space constant, flows a gas along a route in the discharge space after passing through an inner space in each hollow cathode, a power supply for supplying an electric power for generating a main discharge across the hollow cathode and the anode after a pre-discharge is produced across each hollow cathode and the anode, and ultraviolet extracting means for extracting ultraviolet light radiated from a plasma which is produced by a discharge in the discharge space.

1. Field of the Invention
The present invention relates to a vacuum ultraviolet (VUV) light source for generating an ultraviolet light by utilizing radiation light originating from a discharge plasma.
2. Description of the Related Art
In the case where an amorphous silicon thin film is formed through the direct dissociation of SiH.sub.4 by light, is necessary to use vacuum ultraviolet light.
A so-called .pi.-type discharge tube as shown in FIG. 10 is well known as a light source for generating vacuum ultraviolet light having a wavelength of below 180 nm.
This type of vacuum ultraviolet light source includes a cylindrical discharge tube 1 and a pair of electrodes 2 and 3 are located in the discharge tube in a spaced-apart relation. A window 4 is provided on one side end of the discharge tube 1 to take out ultraviolet light. A coolant passage 5 is provided outside the discharge tube 1 to allow a flow of a coolant. The discharge tube 1 has its inside adequately evacuated and a rare gas, hydrogen or denterium, is filled in the discharge tube 1 to an extent that a predetermined pressure can be maintained in the discharge tube. A power supply 6 supplies a power necessary for a discharge as generated between the electrodes 2 and 3. The power supply 6 charges a storage capacitor 8 through a DC power supply 7 and a switch 9 are used to apply pulse voltage to the electrodes 2 and 3.
When the pulse voltage is applied across the electrodes 2 and 3, a pulse discharge is generated across the electrodes 2 and 3 to radiate ultraviolet light through a plasma involved. The ultraviolet light is taken out from the window 4.
The conventional vacuum ultraviolet light source thus arranged poses the following problem. That is, in order to obtain high-output ultraviolet light, a high current density discharge is required for a current of quick rise time and high peak. In the aforementioned conventional light source a high current level results in an unstable discharge. It is, therefore, not possible to stably maintain the high-density discharge. Since, in the conventional light source, a discharge plasma cannot stably be created in a broader discharge space in a spatially uniform fashion, a corresponding ultraviolet light beam diameter is relatively small on the order of about 30 mm, largely restricting the application range of the light source.
In the conventional vacuum ultraviolet light source, therefore, the radiation efficiency and power output of the vacuum ultraviolet light are low and, therefore, it has been difficult to achieve a large-diameter ultraviolet light beam.


A haptic sense rendering apparatus is disclosed that includes a haptic sense rendering unit, a magnet, a coil that magnetically interacts with the magnet and drives the haptic sense rendering unit, and a drive circuit that generates a drive signal for driving the haptic sense rendering unit to emphasize at least one of a drive starting operation and a drive terminating operation and supplies the generated drive signal to the coil.

1. Field of the Invention
The present invention relates to a haptic sense rendering apparatus that renders haptic information through movement of a haptic sense rendering unit and a method of driving such a haptic sense rendering apparatus.
2. Description of the Related Art
In recent years and continuing, haptic sense rendering apparatuses are being developed for use in operations control devices such as an input unit of a computer, an operations unit of an audio apparatus, and an operations unit of a car navigation system that is installed in a vehicle. Such haptic sense rendering apparatuses are designed to convey information to an operator by rendering a haptic sensation via a haptic sense rendering unit so that the operator may feel a force at his/her fingertips upon touching the haptic sense rendering unit with his/her fingertips.
A flat mobile haptic sense rendering apparatus may have four magnets arranged flat on a plane and drive coils arranged above and parallel to these four magnets, and a thrust may be generated by supplying electric currents through these drive coils, for example. That is, by arranging plural drive coils to face plural magnets that are arranged flat on a plane and controlling the electric current being supplied to these drive coils, a desired force may be generated by the drive coils to thereby cause relative movement of a haptic sense rendering unit. It is noted that Japanese Patent Laid-Open Patent Publications No. 2000-330688 and No. 2004-145748 disclose examples of flat mobile haptic sense rendering apparatuses that implement such a configuration.
In the case of using such a haptic sense rendering apparatus in an input device of a computer or an operations unit of a vehicle, it is desired that the apparatus be miniaturized and the thrust generated by the drive coils be increased.
However, in order to increase the thrust to be rendered by the haptic sense rendering apparatus as is described above, the magnetic fields of the magnets have to be increased or the electric currents supplied to the drive coils have to be increased. To increase the magnetic fields of the magnets, suitable materials may have to be selected or the volume of the magnets has to be increased. It is noted that selecting suitable materials for the magnets may lead to cost increase. Also, in the case of increasing the volume of the magnets, miniaturization of the apparatus may be hampered.
Thus, in order to increase the thrust generated by the drive coils, the electric current supplied to the drive coils has to be increased. However, increasing the electric current supplied to the drive coils may lead to an increase in heat generation. This may be a problem since heat dissipation performance is degraded when the apparatus is miniaturized and heat generation per unit volume may be increased as a result.
Accordingly, there is a demand for a haptic sense rendering apparatus that is small in size and is capable of rendering a strong thrust without causing an increase in heat generation.

Haptic sense rendering apparatus and haptic sense rendering method


A decompressor for an internal combustion engine including a mounting hole in which a decompression valve for opening and closing a pressure relief bore opening into a combustion chamber within a cylinder of the engine, is disposed, and also including a through-hole which is obliquely and rectilinearly formed through a portion of a wall of the cylinder, and through which an outer open end portion of the mounting hole is able to communicate with a scavenging passage of the engine.

The present invention relates to a decompressor for an internal combustion engine.
Hitherto, a decompressor for an internal combustion engine has been known, which decompressor has a decompression valve disposed in a decompression passage through which an intake or exhaust passage of the internal combustion engine is able to communicate with a combustion chamber within a cylinder of the engine. At a starting of the internal combustion engine, the decompression valve is actuated in operational connection with, for instance, the movement of a movable member of a recoil starter so as to relieve pressure from the inside of the combustion chamber to the outside thereof. In this way, the resistance which a piston receives at a starting of the engine is reduced in order to facilitate the starting. However, such a conventional decompressor has a drawback in that the cylinder and peripheral equipment are contaminated with compressed air-fuel mixture being exhausted from the inside of the cylinder through the decompressor directly to the outside of the cylinder. Thus, the conventional decompressor fails to be readily applied to a type of internal combustion engine for a portable or carriable work machine.

Decompressor for internal combustion engine


A storage rack for storing nuclear fuel rod assemblies is provided with an array of cell housings having damping elements which are preloaded against the outer walls of the individual cells. The damping elements are slabs which when preloaded against the cell walls provide a coulomb damping function which is highly effective in absorbing vibration from rough handling or seismic events. The cell housings may be located in alternating positions in the array and cells may be formed from the outer walls of the surrounding cell housings. The cell housings are held together in the array by support bars which are affixed to the top and bottom ends of the cell housings. The support bars may include recesses to align the cell housings.

The invention relates to storage racks for storing nuclear fuel assemblies both during transport and during stationary storage. Preferably, the racks are highly overdamped, enabling them to best withstand vibrations caused by seismic events or rough handling.
Fuel for nuclear reactors is typically configured in the form of elongated fuel rods, which may be separate, stand-alone elements, or may be positioned within canisters. Hereinafter, the fuel rods and rod/canister combinations are referred to as fuel assemblies. Both before and following use, the fuel assemblies must be stored and/or transported with great care. To assure that such care is achieved, storage racks are often used to support a plurality of fuel assemblies in a generally parallel, spaced-apart configuration, while maintaining the fuel assemblies in a subcritical array environment. During storage, the racks and the fuel assemblies contained therein, may be completely submerged in a pool of water. The water provides cooling and additional shielding from nuclear radiation.
The fuel storage racks of the prior art typically consist of an assembly of hollow cells, each defined by an array of elongated rectangular cross-section boxes or compartments. The boxes are typically made by forming sheets of stainless steel into elongated rectangular cross-section tubes and welding the corners of the elongated tubes together to form a matrix of elongated hollow cells, each adapted the receive a single fuel assembly. Exemplary storage racks are disclosed in U.S. Pat. Nos. 4,695,424, 4,857,263, 4,948,553, and 4,366,115. A neutron absorbing (or "poison") material, such as borated stainless steel, is typically welded or otherwise rigidly affixed to each of the walls of boxes to absorb neutron flux from the fuel assemblies which may be positioned within the boxes, thereby avoiding an undesirable concentration of neutrons.
These prior art storage racks suffer from several disadvantages. For example, neutron absorbing elements, and particularly those made borated stainless steel, are expensive and difficult to form and weld to the walls of the boxes. Further, the individual cells are known to be weak along the top edge and have little torsional or crush strength. In addition, storage racks constructed in this way have little resistance to vibration, such as may be caused by seismic events. Due to the reactive nature of the nuclear fuel assemblies, such damage to the storage racks can be disastrous.
Accordingly, it is an object of the present invention to provide an improved storage and/or transport rack for nuclear fuel assemblies.
Another object of the present invention is to provide an improved storage rack for nuclear fuel assemblies which is highly overdamped to enable the rack to withstand the vibration of seismic events or rough handling such as may be encountered during transportation of the rack.
It is another object to provide a storage rack for nuclear fuel assemblies which has improved torsional and crush strength.
A further object is to provide an improved storage rack for nuclear fuel assemblies which may De easily and inexpensively manufactured.
Other objects of the invention will in part be obvious and will in part appear hereinafter.

Highly damped storage rack for nuclear fuel assemblies