A digital audio system configured to facilitate a collaborative audio session comprises a first digital audio device operable by a first user, a second digital audio device operable by a second user independently of the first digital audio device, and a server configured to communicate with the first digital audio device and the second digital audio device over a network, receive a request from at least one of the digital audio devices for participation in a collaborative audio session, and facilitate communication between the first digital audio device and the second digital audio device.

Digital audio players, whether implemented in hardware or software, are widely available and popular for storing and/or playing digital audio content (e.g., digital audio streams, encoded sound recordings, etc.). Digital audio content may be digitized into different formats based on variables, such as bit rate, communication protocol(s), physical medium, compression algorithm, and/or other variables. Common digital audio formats include, without limitation, MPEG (e.g., MP3, etc.), WAV, MIDI, and/or other formats known to those skilled in the art. Digital audio content in various digital formats can be transmitted, as a file or as a data stream, over wireless and/or wired communication networks via appropriate protocols (e.g., HyperText Transport Protocol (HTTP), Real-Time Streaming Protocol (RTSP), and/or other protocols).
Exemplary digital audio players implemented in hardware include, without limitation, Apple iPod, SONICblue Rio, Casio's MP3 audio wrist watch, Compaq iPaq, and other players known to those skilled in the art. Exemplary digital audio players implemented in software include, without limitation, MusicMatch's Jukebox, Realplayer, Microsoft Media Player, and other software players known to those skilled in the art.
Typically, a digital audio player has functions that allow a user to enjoy digital audio content in different ways. These functions may include playback, record, forward, reverse, skip, random play, repeat, and/or other functions. However, digital audio players generally do not provide any audio content manipulation functions, such as DJ functions. Exemplary DJ functions include mixing, scratching, fading, reverse play, looping, and/or other functions. These functions are referred to as DJ functions because they are typically provided by specialized DJ digital turntables, whether implemented in hardware or software, to be used by professional DJs. These functions are known in the art and need not be described in more detail herein.
Professional DJs using a specialized DJ digital turntable are able to perform DJ functions on digital audio content, for example, to create audio content for subsequent distribution via some type of media or for live events. Exemplary DJ digital turntables implemented in software include, without limitation, Acid Pro from Sonic Foundry and American Audio Pro Mix MP3 Player.
The DJ digital turntables are generally designed to be used and controlled by individual DJs and are not readily usable by groups of collaborators (e.g., to create a collaborative audio session and/or live jamming session), particularly if the would-be collaborators are not in the same location. Conversely, digital audio players are generally designed to be used and controlled by individual users. In other words, the networked interactivity that is available for other communications formats (e.g., discussion forums and instant messaging for text, videoconferencing for meetings, etc.) is not available for music and many other types of audio content.
Thus, a market exists for a digital audio system that enables multiple users of digital audio players to be able to join in a collaborative audio session via a networked environment.

Hewlett-Packard Development Company, L. P.


An electronic apparatus includes a locker having a plurality of shelves, and a plurality of packages 25 are inserted in the respective shelves from the front thereof. Back boards are arranged in the locker at the rear of the shelves. A plurality of back connector boards are attached to the locker from the rear thereof. The connector of the package is plugged-in to the front the connector of the back board, and the connector of the back connector board is plugged-in to the rear connector of the back board. The back connector board also has external line connectors and an interface circuit or other circuits such as a radio interference reducing circuit and a lightning arrester.

1. Field of the Invention
The present invention relates to an interface structure for an electronic apparatus. In particular, the present invention relates to an interface structure, for various electronic apparatuses, with small size and high density and designed to facilitate connecting operations.
2. Description of the Related Art
In recent years, an electronic apparatus such as a communication equipment rarely functions by itself and usually has some electrical connections to other external devices. The method of connection includes various electrical and physical interface conditions, and the number of external line connections per unit device has tended to increase considerably.
As an example of the conventional interface structure of an electronic apparatus such as a communication equipment locker, an telephone exchange or a computer, the arrangement which can realize external connections at the back of the apparatus and connections between the shelves is shown in the perspective view of FIG. 8 and the exploded side view of FIG. 9. As shown in these figures, the communication apparatus comprises a locker 1 and one or a plurality of shelves 2 arranged in the locker 1. The shelf 2 is configured to house a plurality of packages 3, and a back board 4 is mounted to the rear of the shelves 2. The back board 4 has connectors 6 mounted thereto, to which connectors 5 of the packages 3 are fitted. Thus, electrical connection between the packages 3 housed in each shelf 3 is established.
Also, the electrical connection between the shelves 2 is established by cables 8 and connectors 7 arranged on the back of the back board 4 connected to the connectors 6.
For electrical connection to external devices, it is possible to use the cables 8 for inter-shelf connection, but the cables 8 are rarely extended to the outside of the apparatus directly as external lines. This is attributable not only to the problem of the electrical characteristics of the cables but also to the problem of the connection strength of the connectors 6 and 7, a limited number of connections and the connection work. For this reason, a terminal board 9 is arranged on the housing of the locker 1, the terminal board 9 having coaxial cable connectors 10 and signal connectors 11 for external line connection which are connected to the connectors 7 on the back board 4 by special conversion cables 12.
Also, in some cases of the recently-employed external line connection, circuits and connectors are prepared in the apparatus in corresponding to characteristic impedances. As an example of a plurality of kind of connection, as shown in FIG. 8, both the coaxial cable connectors 10 and the signal connectors 11 for external line connection are prepared and one of them is selectively used to adapt the impedance difference of the devices to be connected (other equipments). Also, the packages 3 having two types of circuits are provided, which are selectively used by switching.
The number of external line connections required per apparatus is currently increasing to the range from about 100 channels to about 300 channels. In the conventional method in which the required number of connectors are attached to the back board 4 and connected to the external line connectors on the terminal board 9 by the cables, the allowable number of external line connections is limited to at most 100 channels due to the wiring space or the like.
In addition, a radio interference reduction filter 13 and a lightning arrester 14 are often arranged in the external line interface structure, and the filter 13 and the lightning arrester 14 are conventionally arranged in the package 3 having an interface circuit 15, as shown in FIG. 9.
Further, some apparatuses are arranged to carry out a standby switching operation for failures. To this end, a standby package is arranged in the shelf 2, and the input/output line is switched between the standby package and the operating package in which a failure occurs. A theoretical block diagram with a simplified conventional configuration is schematically shown in FIG. 10.
FIG. 10 shows an 8-to-1 standby switching configuration. When one of packages #0 to #7 develops a failure, the input/output line is switched to the package #8. Realization of this function requires a switching control package 16 capable of switching any lines of packages #0 to #7. This switching control package 16 is arranged in the shelf 2.
The above-mentioned conventional external line connection arrangement includes a measure for meeting the requirements for a plurality of kinds of connections and for the increased number of connections. This conventional arrangement has the following problems: (1) As seen in FIG. 11 showing the rear view of the locker and FIG. 12 showing the side view of the locker, 100 or more external lines may be sometimes required for each shelf 2, resulting not only in an increased cost of equipment and material but in an increased number of wiring operation steps due to the variety of connection forms. (2) In the case of (1) above, the cables from the back board 4 are laid within the locker 1 and connected to the external line connectors 10, 11 on the terminal board 9, and there are a plurality of types of connectors so it is impossible to accommodate more than 100 cables. (3) The radio interference reduction filter 13 is mounted to the package 3, and the noise on the special external line cable 12 is conveyed to the outside, bypassing the filter 13. As a result, there is a possibility that external portions relative to the apparatus are adversely affected. (4) An impedance-switching circuit is required on the package 3, thereby deteriorating the efficiency with which the packages 3 are arranged.
Further, in the circuit to carry out the standby package switching control for failures the switching control package 16 is necessary and the wiring is very difficult since the lines are extended to the switching control package 16 with the increased number of cables on the back board 4, shown in the block diagram of FIG. 10.

Interface structure for electronic apparatus


An integrated disposable cartridge for dialysis or ultrafiltration treatment of blood includes integral pressure sensors. Sensors are embedded in the blood filter on the cartridge to measure the pressure of blood or other fluids in the filter.

This invention relates to an apparatus for the extracorporeal treatment of blood. More specifically, the invention relates an apparatus to treat patients by removing excessive fluids, such as water, from the blood of patients suffering from fluid overload.
1. Mechanical Fluid Removal Therapies
Patients that exhibit symptoms of body fluid overload retain excessive amounts of fluid in the abdomen, legs and lungs. For example, excessive fluid in the lungs, referred to as edema, can cause patients to have difficulty breathing. Moreover, edema in the lungs leads to poor blood oxygenation. Poor oxygenation leads to acidosis and deleterious neurological and hormonal phenomena that increases vasoconstriction and load on the heart. In addition, vasoconstriction leads to reduced blood flow to the kidneys and diminishes the effectiveness of the main pharmacological means of fluid removal—diuretic treatment. The reduced blood flow can result in kidney failure.
Different modalities of Continuous Renal Replacement Therapy (CRRT) have been used to treat patients suffering from excess fluid overload and acute renal failure. In the acute condition, CRRT has been performed using standard methods of hemodialysis and continuous arterio-venous hemofiltration (CAVH). More recently, continuous veno-venous hemofiltration (CVVH) has been used to reduce the complications associated with such issues as hemodynamic instability and need for arterial access.
Hemodialysis and hemofiltration can be used to remove excess fluid from a patient, especially in patients whose kidneys have failed. The term "Renal Replacement Therapy" generally refers to all forms of dialysis, solute and fluid balancing therapy. Another category of patients affected by fluid overload are those with congestive heart failure (CHF). Patients suffering from CHF have weakened hearts that are unable to provide normal blood flow to the kidney and organs of the body. CHF patients may have normal kidneys, but lack sufficient blood flow to maintain proper kidney functions of removing excess fluid, e.g., water, from the body. The build-up of excessive fluids due to inadequate kidney functions further increases the blood pumping load on the heart, which is already suffering from CHF.
Renal replacement therapy performs two primary functions: ultrafiltration (removal of water from blood plasma), and solute clearance (removal of different molecular weight solid substances from blood plasma). The filter utilized, also called hemofilter or "dialyzer", can be set up to perform either or both of these functions simultaneously, with or without fluid replacement. Similarly, the various modes of renal replacement therapy relate to whether fluids, solutes or both are removed and whether fluids are replaced. "Clearance" describes the removal of substances, both normal and waste product, from the blood whether by kidney function or during renal replacement therapy.
Dialysis is the diffusive transfer of small solutes out of a blood plasma compartment by diffusion across the membrane itself. It occurs as a result of a concentration gradient, with diffusion occurring from the compartment with higher concentration (typically the blood compartment) to the compartment with lower concentration (typically the dialysate compartment). Since the concentration of solutes in the plasma decreases, clearance is obtained, but fluid may not be removed. Ultrafiltration can be combined with dialysis.
Hemofiltration is the combination of ultrafiltration and fluid replacement, typically in much larger volumes than needed for fluid control. The replacement fluid contains electrolytes, but not other small molecules. Since the net effect of replacing fluid without small solutes and ultrafiltration of fluid with small solutes results in net removal of small solutes, clearance is obtained.
Existing renal replacement therapy machines and specifically those used in acute setting to perform (Slow Continuous Ultrafiltration) SCUF and CVVH therapy were designed to primarily perform hemofiltration and hemodialysis, not merely fluid removal. Blood is composed of cellular components suspended in the fluid component called plasma. Water is the primary constituent of plasma in which physiological solutes such as sodium and potassium are dissolved. Also, in plasma, larger molecules, such as proteins and blood cells, are suspended. Hemofiltration and hemodialysis remove solutes (and some larger molecules) in addition to fluid removal. Ultrafiltration relates to fluid removal from blood, and does not remove solutes or larger molecules.
Ultrafiltration and hemofiltration operate primarily by convection. In hemofiltration, a solute molecule is swept through a filter membrane by a moving stream of ultrafiltrate. Proteins and blood cells are retained in the blood by the membrane. In patients with renal failure, renal replacement therapy, such as hemofiltration or dialysis, removes undesired solutes. In renal replacement therapy, vital elements such as electrolytes are also removed from the blood and need to be replaced to maintain electrolyte balance. Thus, hemofiltration and dialysis treatments usually require fluid replacement. In contrast, ultrafiltation does not remove substantial amounts of electrolytes and solutes.
During hemofiltration solute removal is entirely dependent on convective transport. Hemofiltration is relatively inefficient for solute removal, as compared to dialysis. Hemodialysis allows the removal of water and solutes by diffusion across a membrane in the direction of the concentration gradient. Diffusion transfers solute molecules across the membrane in the direction of the lower solute concentration at the rate inversely proportional to the molecular weight.
Hemodialysis requires a large filter membrane surface to enable effective solute clearance by diffusion. Hemofiltration requires large amount of ultrafiltrate to be transferred across the membrane to remove a relatively small amount of solute. This is a consequence of convection being an inefficient method of solute transport. Large amounts of fluid such as 1 to 4 liters per hour (L/hour) are continuously being removed during CVVH. The resulting loss of water and electrolytes are immediately dangerous to the patient. To maintain fluid and electrolyte balance, equally large or slightly lower amount of replacement fluid is infused into the patient. Replacement fluid is thus added into the extracorporeal blood circuit before or after the filter.
Ultrafiltration utilizes extracorporeal blood filters to remove fluids from blood, where the filter generally includes a blood passage having input and output ports, a filtered fluid discharge port and a finely porous membrane separating the blood passage and the ultrafiltrate of filtrate discharge port. Ultrafiltration involves the convective transfer of excessive fluid out of the blood plasma from the blood passage, through pores in the membrane, and to the discharge port of the filter. The pores filter electrolytes and small and middle sized molecules (up to 20,000 to 30,000 daltons) from the blood plasma. Importantly, since the concentration of small solutes is the same in the ultrafiltrate as in the plasma, effectively, no clearance of solutes from the blood plasma occurs during ultrafiltration. Accordingly, the ultrafiltrate output from the filter is substantially all fluids, e.g., water, and is relatively free of solutes.
2. Limitations of Existing Devices for Ultrafiltration
Dialysis machines historically used sets of disposable components that are assembled of various parts from different manufacturers. This allowed flexibility but had certain disadvantages. Joints between component parts may leak, allow ingress of air and facilitate blood clotting. High skill was required from hospital nurses and technicians to assemble tubes, connectors, filters and accessories and then load them correctly into pumps, bubble detectors, pressure sensors and other interface elements of a dialysis machine. In the setting of a chronic dialysis center such practice was acceptable. However, in an acute setting, such as an Intensive Care Unit (ICU) of a hospital, the complexities of dialysis machines became an impediment.
As a result, use of mechanical fluid removal in the ICU, Emergency Rooms and general floors of a hospital has been limited. One United States manufacturer recently released sophisticated apparatus marketed under the tradename "Prisma"™ by Hospal-Gambro. It uses an integrated set of disposable dialysis components in which tubing, filter and accessories are bonded together and no assembly is required. The filter, sensor interfaces and four dedicated pump segments (for blood, dialysate, replacement solution and effluent) are mounted on a flat plastic cartridge to simplify the loading of the dialysis pumps. The Prisma™ machine is advertised as "an integrated system for continuous fluid management and automated renal replacement therapy blood."
While Prisma™ has been a significant advancement in the state of the art and has enjoyed wide adoption, it has its deficiencies. One deficiency is that, although the Prisma™ set of disposable dialysis components is continuous and bonded together, it does not present a smooth blood path but incorporates elements that create stagnant and slow moving blood zones. In such zones blood clots are likely to form. It also employs an interface to pressure sensors that is relatively inaccurate, unreliable and requires maintenance. There is a need for an improved design of the blood flow dialysis set that is simple to use, requires no maintenance or special training, and has improved performance over the existing set of disposable components for the Prisma™ machine.
In addition, the Prisma™ set does not integrate pressure sensors. Instead it integrates pressure "pods" shaped as domes. The interface surface of a pod is made out of silicon membrane approximately one inch in diameter. When mounted on the Prisma machine pods interface with the permanently installed pressure sensors that are the part of the machine. The interface is sealed by a rubber gasket so that the pod membrane serves as a lid on the pressure transducer cavity. When in operation, blood and other fluids flow through pods and come in contact with the membrane.
Pressure pods provide a means to measure the pressure of blood and other fluids flowing outside an interface surface. When the pressure inside the pod is increased the diaphragm stretches and thereby compresses the air inside a transducer cavity. As a result pressure in the bloodline or a fluid line is measured. The pod membrane serves as a barrier between the blood and potential contamination from environment, as is similar to the clinical invasive vascular blood pressure measurements. This method, although functional, has several deficiencies:
1. To be accurate pods have to be positioned perfectly when the pressure inside is atmospheric. Over time, if there is even a miniscule leak on the transducer side of the membrane, pod will creep and gradually stop transmitting pressure accurately because of the tension in the membrane.
2. Stretchable membranes and air filled transducer cavities add compliance to the circuit. Compliance is a delay in a pressure measurement due to the time required to stretch the pods and compress the air inside the pod cavity. Compliance is not desired since it makes the system less responsive to controls.
3. Pods filled with blood increase the blood-plastic contact surface and create stagnant zones with low blood flow velocity that facilitate clot formation. Because clots may form in the pods, the use of pods also necessitates the use of clot capture devices.
4. Pod domes have significant volume that increases the total extracorporeal volume of blood. This increased volume also increases the time that blood spends in contact with foreign materials. Altogether this increases risks of blood loss, hypotension and clotting.

Blood pump having a disposable blood filter with integrated pressure sensors


A coating composition for metal or refractories includes a polysilazane resin; and one or more additives that alter the thermal conductivity and/or the abrasion resistance of the cured polysilazane resin. The coating composition may be applied to a metal or refractory material substrate and heated to form a ceramic layer on the substrate. The ceramic layer exhibits lower thermal conductivity and increased abrasion resistance.

1. Field of the Invention
The invention generally relates to coatings for metals and refractory materials. More specifically, the invention relates to coatings for metals and refractory materials that provide improved heat and wear resistance to the coated material.
2. Description of the Relevant Art
Metals and refractory materials are used in many applications that involve high temperatures, pressures and stress. The eventual failure of these materials is typically due to a combination of heat weakening of the metal, wearing and corrosion, depending on the application. Metals used in applications such as firearm components (e.g., the barrel), internal combustion engines, deep sea drilling rigs, turbochargers, superchargers, high pressure pumps, structural metal (e.g., for high rise buildings, bridges, etc.) are all subjected to varying stresses that eventually lead to decreased strength or failure.
For example, it is known that firearm barrels become heated during use and such heating can lead to changes in the barrel that effect the accuracy or operation of the firearm. A firearm is a weapon that launches one, or many, projectile(s) at high velocity through confined burning of a propellant. The burning of the propellant fills the interior of an ammunition cartridge or the chamber of a firearm, leading to the expulsion of a bullet or shell. Heat produced by the burning propellant, as well as the heat produced by the projectile(s) are accelerated through the barrel, causes the temperature of the barrel to rise. As the temperature of the barrel rise, the barrel may change shape, changing the accuracy of the firearm and also loses some of its strength. If the firearm is being used to fire multiple projectiles at a rapid rate, the barrel will continue to heat up until, becoming softer and less accurate. If the heat is not properly dissipated by the barrel, the barrel will eventually undergo mechanical failure. The barrel, therefore, becomes the limiting factor for the rate at which projectiles can be fired from the firearm, and/or the velocity at which the projectiles are fired.
Metals and refractory materials may include a chromium coating. Chromium coatings reduce the friction between the components during operation. For example, in firearms, a chromium coating placed on the barrel bore will reduce the friction between the projectile and the barrel, producing less heat. A chromium coating may also provided increased resistance to corrosive materials.
Chrome is a heavy metal which is deposited onto the metal surface using, for example, aqueous electrodeposition. The chromic acid used in the deposition process is a hazardous substance and is a major problem when it comes to environmental pollution prevention efforts and worker safety. Hexavalent chromium, used in electrodeposition processes, is a known carcinogen which is difficult and expensive to dispose of.
It is desirable to have alternate coatings for metals and refractory materials that are not as toxic and are simpler to produce.

Durable ceramic nanocomposite thermal barrier coatings for metals and refractories


A method and apparatus for the high volume manufacture of fluid infusion devices which embody a self-contained, stored-energy source for expelling fluids from the reservoir of the device into an ambulatory patient at precisely controlled rates over extended periods of time. In accordance with the method of the invention, the base and cover infusion components of the devices of the invention are manufactured in injection molded arrays which comprise a cover array which is superimposed over and connected to a base array with the elastomeric membrane being captured therebetween. The elastomeric membrane material, which forms the stored-energy source of the infusion devices, is continuously unrolled from a large roll of film-backed membrane material which is rotatably mounted on a turret assembly upon which a second back-up roll of elastomeric membrane material is also mounted. After being unrolled, the film backing is separated from the membrane and the membrane is introduced into a novel tenter apparatus which controllably, biaxially stretches the membrane material. Following the stretching step, the membrane is automatically cut and then sealed between the cover components and base components of the cover and base arrays. The finished, individual infusion devices are then separated from the arrays and automatically packaged for shipping.

1. Field of the Invention
The present invention relates generally to methods and apparatus for making fluid delivery devices for infusing medicinal agents into an ambulatory patient at specific rates over extended periods of time. More particularly, the invention concerns a novel method and apparatus for the large volume manufacture of small, disposable fluid delivery devices for infusion of medicinal agents into a ambulatory patient.
1. Discussion of the Prior Art
Many medicinal agents require an intravenous route for administration thus bypassing the digestive system and precluding degradation by the catalytic enzymes in the digestive tract and liver. The use of more potent medications at elevated concentrations has also increased the need for accuracy in controlling the delivery of such drugs. The delivery device, while not an active pharmacologic agent, may enhance the activity of the drug by mediating its therapeutic effectiveness. Certain classes of new pharmacologic agents possess a very narrow range of therapeutic effectiveness, for instance, too small a dose results in no effect, while too great a dose results in toxic reaction.
In the past, prolonged infusion of fluids has generally been accomplished using gravity flow methods, which typically involve the use of intravenous administration sets and the familiar bottle suspended above the patient. Such methods are cumbersome, imprecise and require bed confinement of the patient. Periodic monitoring of the apparatus by the nurse or doctor is required to detect malfunctions of the infusion apparatus.
The fluid delivery devices made in accordance with the method of the present invention overcome many of the drawbacks of the prior art by making use of advanced types of prestressed elastomeric films which, in cooperation with a base, define a fluid chamber that contains the fluid which is to be dispensed. The prestressed elastomeric film membrane, which is further distended during the filling of the fluid chamber, controllably forces fluid within the chamber outwardly of the device as the membrane moves toward its less distended stating configuration.
The elastomeric film materials used in the fluid delivery devices manufactured in accordance with the methods of the present invention, as well as various alternate constructions of the fluid delivery devices themselves, are described in detail in U.S. Pat. No. 5,205,820 issued to the present inventor. Therefore, U.S. Pat. No. 5,205,820 is hereby incorporated by reference in its entirety as though fully set forth herein. Co-pending U.S. Ser. No. 08/451,520 filed by the present inventor on May 26, 1995 also describes several alternate constructions of fluid delivery devices that can be manufactured in accordance with the teachings of the present invention. This co-pending application, which also discloses an apparatus for making fluid delivery devices on an individual basis, is also hereby incorporated by reference in its entirety as though fully set forth herein.
As will be better appreciated from the discussion which follows, the methods and apparatus of the present invention are ideally suited for the large-scale manufacture of fluid delivery devices of the character described herein and in application Ser. No. 08/451,520. These delivery devices typically comprise a base assembly and a stored energy means provided in the form of a thin, prestressed, distendable, elastomeric membrane which after being cut in a manner described in Ser. No. 08/451,520, cooperates with the base assembly to form a fluid reservoir. Contained within a cavity formed in the base assembly is circuitously shaped, hollow cannula which includes an inlet in communication with the fluid reservoir and an outlet formed in a needle-like segment, which extends generally perpendicularly downward from the lower surface of the base assembly for subdermal infusion of medicinal fluids into the patient.
The novel fluid delivery devices manufactured in accordance with the present invention have an extremely low profile and are eminently capable of meeting the most stringent of fluid delivery tolerance requirements. The devices are small, easy to use and, in accordance with the method of the present invention, can be manufactured in very large quantities at low cost.

Method and apparatus for making fluid delivery device


A system and method for inductively heating a work piece. The induction heating system is coupleable to at least one temperature feedback device. The temperature feedback device is disposed within the induction heating system to provide a signal representative of the temperature of an induction heating system component. The induction heating system is operable to control the output of the induction heating system based on the temperature of the induction heating system component to protect the component from heat damage.

The present invention relates generally to electronic systems and, particularly, to a system and method for controlling the output power of an electronic system based on operating parameters of the electronic system.
An induction heating system is a system that utilizes a varying magnetic field to heat an object. A work piece placed inside or proximate to the induction heating device is exposed to the varying magnetic field. This varying magnetic field induces movement of the electrons within the work piece, causing eddy currents to flow in the work piece. The eddy currents and resistance to current flow within the work piece cause the temperature of the work piece to rise. The amount of heat induced in the work piece may be controlled by changing the magnetic field strength as a result of varying the amount of alternating current flowing through the induction heating device.
An induction heating power source used in an induction heating system may operate with relatively large amounts of electrical current. As a result, the temperature of the components generating or transmitting the electrical current may rise dramatically during operation of the system. To dissipate this heat a liquid may be used to cool some induction heating system components, such as induction heating cables, during operation to prevent heat damage from occurring. However, even these liquid-cooled components may be vulnerable to heat damage when operated at or near their operational limits, or if placed in proximity to an inductively heated object.
In addition, damage may occur to components of the induction heating power source as they are utilized at levels beyond their operating limits. Moreover, the electronic components of the system may be damaged directly by the current flowing through them or the voltage across them. For example, solid-state components, such as transistors, used in the manipulation of electrical current may be especially vulnerable to heat damage caused by the electrical current flowing through them.
Therefore, a technique is desired that will protect electrical components of a system from damage that may occur as a result of the operation of the system. More particularly, a technique is needed for protecting the components of an induction heating system based on operating parameters of the induction heating system.

Induction heating system and method of output power control


The invention provides an activated carbon supported cobalt based catalyst for directly converting of synthesis gas to mixed linear alpha-alcohols and paraffins, comprising cobalt, an activated carbon carrier, a metal promoter which is at least one selected from the group consisting of a zirconium component, a lanthanum component, a cerium component, a chromium component, a vanadium component, a titanium component, a manganese component, a rhenium component, a potassium component, a ruthenium component, a magnesium component and a mixture thereof, wherein the cobalt and the promoter are deposited on the activated carbon carrier or substantially uniformly dispersed therein, and the metal promoter is present in the form of a metal, an oxide or a combination thereof.

The search for processes to provide alternate feedstocks for fuels and chemicals, and particularly high quality diesel fuels and high value mixed linear alpha-alcohols, has been prompted due to the potential shortage of traditional petroleum reserves, and the increasing instability of international hydrocarbon resources.
Almost as old as the Fischer-Tropsch process for making hydrocarbons is the Fischer-Tropsch process for making alcohols. The Fischer-Tropsch process is carried out by passing a mixture of CO and H2 over a catalyst for the hydrogenation of CO. Numerous catalysts and catalytic methods have been studied in an attempt to provide a viable method for the production of aliphatic alcohols from synthesis gas.
Three main types of processes have been proposed for preparing alcohols from gaseous mixtures comprising carbon monoxide and hydrogen. One of these is a modified Fischer-Tropsch process which involves the use of alkali metal-containing iron based catalysts. Generally, this process suffers from poor selectivity and low productivity. Another process is the iso-butyl synthesis as used in Europe between 1935 and 1945. This process is analogous to the methanol synthesis process and utilizes a similar catalyst, i.e. zinc chromite, modified by addition of an alkali metal salt, at high temperature and high pressure. Typically, the main products from this process comprise methanol (50%), ethanol (20-40%), n-propanol, and higher alcohols which are predominantly non-linear primary and secondary alcohols. The third process was originally assigned to Dow Chemical Company, in which primarily C1 to C4 mixed alcohols are produced in good yield over a supported catalyst based on molybdenum disulfide.
A typical review article related to alcohols preparation is R. B. Anderson et al. "Industrial and Engineering Chemistry" vol. 44, No. 10, pp. 2418-2424. A number of catalysts containing zinc, copper, chromium, manganese, thorium and iron, occasionally promoted with alkali or other materials for making various alcohols are listed in this article.
U.S. Pat. No. 4,504,600 provides a CO hydrogenation process for producing alcohols utilizing thallium-promoted iron-based catalysts. A mixture of CO and H2 is selectively converted to liquid C6˜C12 hydrocarbon containing C6˜C12 alcohols hydrocarbons in an amount of 4˜8 wt. %, and methane in an amount of 1 wt. %, relative to the total produced hydrocarbons, with a CO2 selectivity of 12˜18 mol. %.
U.S. Pat. No. 4,513,096 discloses a method for reacting carbon monoxide and hydrogen in a slurry phase to form light hydrocarbons and alcohols, in the presence of iron-containing activated carbon.
U.S. Pat. Nos. 4,551,444 and 4,886,651 provide a modified copper based methanol synthesis catalyst, especially a thoria and zirconia promoted copper catalyst, over which higher yields of C1 to C6 mixed alkanols and hydrocarbons are formed from synthesis gas at reaction conditions.
U.S. Pat. No. 4,562,174 discloses a catalyst comprised of copper and zinc oxides, and optionally manganese oxide or manganese and cobalt oxides and a stabilizer such as chromic, ceric, magnesium or aluminum oxides, over which C1 to C6 mixed alcohols and light hydrocarbons are produced through CO hydrogenation.
U.S. Pat. No. 4,780,481 describes a process for manufacturing a mixture of saturated primary alcohols by reacting carbon monoxide with hydrogen in the presence of a catalyst formed essentially of copper, cobalt and zinc, promoted by alkali and alkaline earth metals and optionally zirconium and rare earth metals.
U.S. Pat. No. 4,943,551 describes a catalyst composition for the production of methanol and higher saturated aliphatic alcohols from synthesis gas. The catalyst consists essentially of copper, thorium, zirconium and an alkali metal.
U.S. Pat. No. 4,725,626 discloses a catalyst and a process for the production of alcohols from CO and H2. The catalyst has the formula: RuCuaMbAcN2Ox, wherein A is an alkali metal or an alkaline earth metal or mixture thereof, and M is Mo and W or mixtures thereof.
U.S. Pat. No. 4,751,248 discloses a process for converting synthesis gas (H2/CO) to aliphatic alcohols containing at least 2 carbon atoms, comprising the steps of passing the synthesis gas firstly through a catalyst zone wherein the catalyst comprises (a) Co metal and/or Co oxide and (b) MgO and/or ZnO (preferably MgO), and then through a catalyst zone wherein the catalyst comprises (c) Cu metal and/or Cu oxide and (d) ZnO.
U.S. Pat. Nos. 4,980,389 and 4,983,638 disclose a catalyst and a method for preparing a mixture of lower aliphatic alcohols. The method includes reacting a mixture of CO and H2 under suitable conditions of temperature and pressure, in the presence of a catalyst composition comprising rhodium, cobalt, molybdenum and a combination of potassium and rubidium.
U.S. Pat. No. 4,749,724 describes a process for forming an alcohol fraction boiling in the boiling range of motor gasoline that is enriched in higher alcohols, comprising the step of contacting a mixture of H2 and CO, and a lower alkanol with a catalyst comprising (1) molybdenum, tungsten or a mixture thereof in free or combined form; (2) an alkali or alkaline earth element; and (3) a support.
U.S. Pat. Nos. 4,675,344 and 4,775,696 state that a method for controlling the ratio of methanol and higher alcohols produced in a process for making mixed alcohols by contacting a H2/CO mixture with a catalyst which contains molybdenum, tungsten or rhenium, said method comprising adjusting the concentration of a sulfur releasing substance in the feedstock.
U.S. Pat. Nos. 4,661,525, 4,752,622, 4,824,869 and 4,825,013 disclose that mixed alcohols are produced from a mixture of CO and H2 using an easily prepared catalyst which comprises a catalyst metal, a co-catalyst metal, and a support, wherein the catalyst metal is molybdenum, tungsten or rhenium, the co-catalyst metal is cobalt, nickel or iron, and the catalyst is promoted by an alkali or alkaline earth metal.
U.S. Pat. Nos. 4,752,623, 4,831,060 and 4,882,360 disclose a process for selectively making C1-C6 alcohols from synthesis gas, comprising the step of contacting a mixture of H2/CO with a catalytic amount of a catalyst wherein the catalyst is consisted of (1) a catalytically active metal, such as molybdenum, tungsten or rhenium; (2) a co-catalytic metal, such as cobalt, nickel, or iron; (3) an alkali or alkaline earth metal; (4) an optional support. The catalyst has to be sulfidized before the contact.
More recently, U.S. Pat. Nos. 6,248,796 and 6,753,353 disclose a method for the production of mixed alcohols by using a sulfidized transition metal catalyst selected from Group VI metals, such as molybdenum or tungsten; nano-sizing the metal catalyst during its synthesis; suspending the catalyst in solvents to form a slurry; adding a sulfur-containing material to extend the catalyst life; and contacting this slurry with a mixture of CO and H2.
Previous catalytic methods have been notably effective for converting CO and H2 feedstocks into hydrocarbons and C1 to C6 alcohols, but none has been particularly effective for providing a substantial yield of a higher aliphatic C2 to C18, especially C6 to C18 alcohols at a moderate temperature and pressure.
An extensive amount of works have been carried out in order to modify and improve the selectivity of a process for producing C6-C18 alcohols, especially C6-C18 linear alcohols, particularly under conditions that low methane and CO2 are produced. Such a process is desired since C6-C18 linear alcohols are industrially important and used in detergents, surfactants, lubricants and plasticizers.
Thus far, no one has disclosed an activated carbon supported cobalt based catalyst which affords improved yields of paraffins and mixed linear alpha-alkanols from the reaction between carbon monoxide and hydrogen, which minimizes the need for an additional step for the separation of products from the catalyst and which permits the use of high space velocities.
There are two processes for the production of synthetic linear alcohols which are (a) ALFOL® process and EPAL® process, based on the work of Prof. Dr. Ziegler, using organic aluminum compounds and (b) an oxo-process (hydroformylation). The former process involves five steps of: hydrogenation, ethylation, growth reaction, oxidation and hydrolysis, while the latter process consists of the reaction of olefins with a H2/CO gas mixture, in the presence of a suitable catalyst, wherein alpha-olefins yield approximately equal amounts of linear and branched aldehydes, and branched alkenes can also be used in this process due to double-bond being isomerized in the presence of the same catalyst. For a long time, paraffin-based processes were predominant for the production of olefins, especially used for detergents, now ethylene has became a preferable raw material. The principal steps in oxo-process are ethylene oligomerization, isomerization and metathesis.
Naphtha is the most common feedstock sent to naphtha cracking units for the production of ethylene. A typical naphtha feedstock contains a mixture of paraffinic, naphthenic, and aromatic hydrocarbons with varied molecular weight and molecular structure. The compositions of naphtha feedstocks vary considerably, while the composition has a significant impact on ethylene and byproduct yields. Normal and branched paraffins convert to ethylene in a cracker, but the ethylene yield from n-paraffin is much greater than those from others. Naphtha is also used primarily as feedstocks for producing a gasoline component having high octane value via a catalytic reforming process. The naphtha distillates produced from Fischer-Tropsch process contains predominantly n-paraffins having 5 to 11 carbon atoms, which are excellent feedstocks for the production of ethylene.
Clean diesel fuels that contain no or almost no sulfur, nitrogen, or aromatics, are or will likely be demanded largely as diesel fuels or in blending diesel fuels. Clean diesel fuels with some mixed alcohols, having relatively high cetane number, are particularly valuable. Typical petroleum-derived distillates are not clean, in that they typically contain significant amounts of sulfur, nitrogen, and aromatics, and they have relatively low cetane numbers. Clean diesel fuels can be produced from petroleum-derived distillates through severe hydrotreating at great expense. The production of clean, high cetane number distillates from Fischer-Tropsch waxes has been discussed in various literatures, but it is reported in few literatures that the catalyst can be used to directly convert synthesis gas to diesel distillates with high quality and with some level mixed alcohols.
Thus, there is a need for an activated carbon supported cobalt based catalyst that cut off the heavier end of the Schultz-Flory distribution, over which mixed linear alpha-alcohols (C2-C18) and the middle distillates (naphtha distillates and diesel fuels) with sulfur-free, nitrogen-free or aromatics-free can be directly synthesized from synthesis gas under moderate condition.

Activated carbon supported cobalt based catalyst for directly converting of synthesis gas to mixed linear alpha-alcohols and paraffins

Dalian Institute of Chemical Physics, Chinese Academy of Sciences


An apparatus, such as a subscriber unit or a base station within a spread spectrum communication system, provides advanced control over the time-tracking of demodulation elements when unresolvable multipath situations arise. The apparatus provides merge protection that prevents clustered demodulation elements from contracting beyond a minimum time span. In addition, the apparatus provides a master/slave feature for synchronizing the time-tracking of the demodulation elements when clustered around a multipath signal.

A number of conventional wireless communication techniques have been developed. One common technique is code division multiple access (CDMA) in which multiple communications are simultaneously conducted over a radio-frequency (RF) spectrum. Example wireless communication devices ("subscriber units") that have incorporated CDMA technology include cellular radiotelephones, satellite radiotelephones, PCMCIA cards for portable computers, personal digital assistants (PDAs) equipped with wireless communication capabilities, and the like.
A CDMA system may be designed to support one or more CDMA standards such as (1) the "TIA/EIA-95-B Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spread Spectrum Cellular System" (the IS-95 standard), (2) the "TIA/EIA-98-C Recommended Minimum Standard for Dual-Mode Wideband Spread Spectrum Cellular Mobile Station" (the IS-98 standard), (3) the standard offered by a consortium named "3rd Generation Partnership Project" (3GPP) and embodied in a set of documents including Document Nos. 3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS 25.214 (the WCDMA standard), (4) the standard offered by a consortium named "3rd Generation Partnership Project 2" (3GPP2) and embodied in a set of documents including "TR-45.5 Physical Layer Standard for cdma2000 Spread Spectrum Systems," the "C.S0005-A Upper Layer (Layer 3) Signaling Standard for cdma2000 Spread Spectrum Systems," and the "C.S0024 CDMA2000 High Rate Packet Data Air Interface Specification" (the CDMA2000 standard), and (5) some other standards. A system that implements the High Rate Packet Data specification of the CDMA2000 standard is referred to herein as a high data rate (HDR) system. The HDR system is documented in TIA/EIA-IS-856, "CDMA2000 High Rate Packet Data Air Interface Specification." Proposed wireless systems also provide a combination of HDR and low data rate services (such as voice and fax services) using a common air interface.
A typical CDMA communication system includes a number of mobile subscriber units that encode voice and data in CDMA waveforms. The subscriber units communicate with base stations, also referred to as base transceiver subsystems (BTS), cell stations, cell sites, or simply cells. A base station demodulates incoming CDMA waveforms received from subscriber units within a limited geographic region, and transmits outgoing CDMA waveforms to the subscriber units. A base station controller (BSC) provides an interface between the base stations and the public switched telephone network (PSTN) for routing the signals to other remote base stations or to any conventional telephony system. In general, transmission from the base station to the subscriber unit is referred to as the Forward CDMA Channel, and is sometimes called a downlink. Transmission from the subscriber unit to the base station is referred to as the Reverse CDMA Channel, and is sometimes called an uplink.
At any given moment, a single subscriber unit or base station may receive multiple replicas of the transmit signal, each replica possibly having a different amplitude, phase and time delay. The replicas are often caused by reflections of the transmit signal off of obstacles in the environment, such as buildings, trees, cars and people. The various replicas of the transmit signal are referred to as "paths," with the general characteristic referred to as "multipath."
The transmit signal of a CDMA communication system consists of a train of pulses called "chips." More specifically, a transmitter generates a spread spectrum transmit signal by modulating an outbound serial stream of data with a pseudonoise (PN) code. The application of the PN code to the data produces a stream of chips. The resulting chips are transmitted according to some modulation scheme, such as quadrature phase shift keying (QPSK) modulation. In order to separate signals from multiple users, the receivers isolate the signal of the desired user by matching the signal to the corresponding PN code.
The rate that the PN code is applied is referred to as the chip rate, which is typically many times faster than the data rate. The duration of one pulse of the PN code is often used as a unit of measure referred to as chip time. The time delay between multiple received paths is often represented in chip time. A time delay of 1.5 chips between two paths, for example, indicates a time delay equal to 1.5 times the chip time of the transmit signal.
In order to reduce effects of signal fading and for other advantages, conventional CDMA receivers discriminate between multiple paths during demodulation. In particular, a typical CDMA receiver, commonly referred to as a RAKE receiver, contains a number of demodulation elements. When the paths have a time separation greater than a threshold, such as approximately 1.5 chips or more, the receiver typically assigns the demodulation elements time offsets corresponding to the different paths. For shorter time separations, often referred to as "unresolvable multipath spacing," conventional receivers typically do not assign multiple demodulation elements because the multiple paths often appear as a single mass of energy without readily detectable peaks. Similarly, if multiple paths shift from greater time separations to unresolvable multipath, the demodulation elements often converge to have the same time offset. When two demodulations elements have "merged" as such, conventional receivers typically deassign one of the demodulation elements.

Time-tracking for clustered demodulation elements in a spread spectrum system


A surface-emitting semiconductor light emitting device comprises an n-type ZnSe buffer layer, n-type ZnSSe layer, n-type ZnMgSSe cladding layer, n-type ZnSSe waveguide layer, active layer, p-type ZnSSe waveguide layer, p-type ZnMgSSe cladding layer, p-type ZnSSe layer,p-type ZnSe contact layer, p-type ZnSe/ZnTe MQW layer and p-type ZnTe contact layer, sequentially stacked on an n-type GaAs substrate. A grid-shaped p-side electrode and a Au film convering the p-side electrode are provided on the p-type ZnTe contact layer. An n-side electrode is provided on the back surface of the n-type GaAs substrate. The active layer has a single quantum well structure or a multiple quantum structure including ZnCdSe quantum well layers.

1. Field of the Invention
This invention relates to a surface-emitting semiconductor light emitting device and, more particularly, to a surface-emitting semiconductor light emitting device, such as semiconductor laser or light emitting diode, capable of surface emission of green to blue light.
2. Description of the Prior Art
Recently, demand has become greater and greater for semiconductor light emitting devices capable of emitting green to blue light, aiming higher recording and reproducing densities or higher resolutions of optical disks and magnet-optical disks, and efforts are devoted to developments of such devices.
U.S. Pat. No. 5,268,918 discloses a semiconductor light emitting device having cladding layers of ZnMgSSe which is one of II-VI compound semiconductors.
Itoh et al. report, in Electronics Letters Vol. 29 No. 9, pulse oscillation of a semiconductor laser of an SCH structure made of ZnCdSe/ZnSe/ZnMgSSe at room temperature.
Ren et al. report, in J. Vac. Sci. Technol. B 12(2), March/April 1994 pp 1262-1265, a LED having a double-heterostructure of ZnSe/ZnCdSe on a ZnSe substrate.

Surface-emitting semiconductor light emitting device


Exemplary methods for performing a statistical analysis of scanned images are disclosed. The methods described herein may be embodied as logic instructions on a computer-readable medium. In one exemplary implementation a correlation value is determined between a scanned image included in a digital file and an original digital image, and a signal is generated indicating whether the correlation value exceeds a threshold.

Images such as photographs, pictures, logos, etc. may be created using digital rendering techniques, or using analog techniques which may be digitized. Digital images may be stored in a suitable storage medium such as, e.g., a hard disk drive, CD-ROM, etc., and may be transmitted across digital communication networks for viewing and/or printing at remote locations.
In certain applications, e.g., security and counterfeit detection, it may be desirable to distinguish between a printed copy of an original digital image and printed copy of a scanned copy of the original digital image or any other printed forgery copy of the original digital image.

Correlative assessment between scanned and original digital images


An improved fluorescence monitoring apparatus for measuring fluorescent emission from a sample in response to sample irradiation by an emission beam is disclosed. The apparatus employs a sample tube having surface roughness characteristics which substantially reduce background fluorescence emission due to contamination of the tube holder in the apparatus. Also disclosed is a method of reducing such background, by texturing of a sample tube to produce desired roughness characteristics.

Fluorescent detection of reaction products is common in a number of analytical settings. Typically, analytical instruments for monitoring fluorescent reactions are equipped with reaction chambers designed to minimize flourescence from external sources, for example, by providing a light-impermeable compartment constructed of non-fluorogenic materials. However, such precautions may not prevent fluorescent emissions from contamination sources, such as flecks of hair or skin introduced to the chamber during sample manipulation.
The present invention provides a sample tube which is constructed to reduce fluorescence from external sources. The tube is particularly usefull in nucleic acid amplification reactions, such as the polymerase chain reaction (PCR) in which progress of the reaction is monitored.
PCR has become a research tool of major importance with applications in cloning, analysis of genetic expression, DNA sequencing, genetic mapping, drug discovery, and the like, e.g. Arnheim et al (cited above); Gilliland et al, Proc. Natl. Acad. Sci., 87: 2725-2729 (1990); Bevan et al, PCR Methods and Applications, 1: 222-228 (1992); Green et al, PCR Methods and Applications, 1: 77-90 (1991); Blackwell et al, Science, 250: 1104-1110 (1990).
While a number of instruments have been developed for carrying out nucleic acid amplification, most employ basic PCR technology, e.g. Johnson et al, U.S. Pat. No. 5,038,852 (computer-controlled thermal cycler); Wittwer et al, Nucleic Acids Research, 17: 43534357 (1989)(capillary tube PCR); Hallsby, U.S. Pat. No. 5,187,084 (air-based temperature control); Garner et al, Biotechniques, 14: 112-115 (1993)(high-throughput PCR in 864-well plates); Wilding et al, International application No. PCT/US93/04039 (PCR in micro-machined structures); Schnipelsky et al, European patent application No. 90301061.9 (publ. No. 0381501 A2)(disposable, single use PCR device), and the like. Important design goals fundamental to PCR instrument development have included fine temperature control, minimization of sample-to-sample variability in multi-sample thermal cycling, automation of pre- and post-PCR processing steps, high speed cycling, minimization of sample volumes, real time measurement of amplification products, minimization of cross-contamination, or sample carryover, and the like.
Recently, PCR designs have focused on instruments that permit the amplification reaction to be carried out in closed reaction chambers and monitored in real time. Closed reaction chambers are desirable for preventing cross-contamination, e.g. Higuchi et al, Biotechnology, 10: 413417 (1992} and 11: 1026-1030 (1993) and Holland et al, Proc. Natl. Acad. Sci., 88: 72767280 (1991). Real time monitoring is particularly desirable in the analysis of diagnostic samples, where high frequencies of false positives and false negatives can severely reduce the value of the PCR-based procedure.
Moreover, real time monitoring of PCR permits far more accurate quantitation of starting target DNA concentrations in multiple-target amplifications, as the relative values of close concentrations can be resolved by taking into account the history of the relative concentration values during the PCR. Real time monitoring also permits the efficiency of the PCR to be evaluated, which can indicate whether PCR inhibitors are present in a sample.
Holland et al (cited above) and others have proposed fluorescence-based approaches to provide real time measurements of amplification products during PCR. Such approaches have either employed intercalating dyes (such as ethidium bromide) to indicate the amount of double stranded DNA present, or they have employed probes containing fluorescer-quencher pairs (the so-called "Tac-Man" approach) that are cleaved during amplification to release a fluorescent product whose concentration is proportional to the amount of double stranded DNA present.
Unfortunately, successful implementation of these approaches has been impeded because the required fluorescent measurements must be made against a very high fluorescent background. Thus, even minor sources of instrumental noise, such as the formation of condensation in the chamber during heating and cooling cycles, formation of bubbles in an optical path, particles or debris in solution, differences in sample volumes--and hence, differences in signal emission and absorbence, and the like, have hampered the reliable measurement of the fluorescent signals.
Parent U.S. patent application Ser. No. 08/235,411, abandoned, describes an apparatus that provides stable and reliable real time measurement of fluorescent indicators of amplification products resulting from any of the available nucleic acid amplification schemes. This apparatus operates by directing into a fluorescent mixture an excitation beam having appropriate energy to excite the fluorescent centers present in the mixture. The present invention is directed to an improvement of this apparatus which includes using a reaction tube that reduces background fluorescence measured from a test sample by reducing the amount of exogenous flourescence that enters the tube from outside sources such as contamination present in the apparatus tube-holder. As particularly described herein, the tube is a plastic consumable tube having an irregular or roughened outer surface that deflects or diffuses incident fluorescence emissions emanating from outside the tube. However, it is also preferable that the tube remain sufficiently clear to permit the human user to visualize fluid volume contained in the tube. Moreover, the tube may be sealable and provide a limited transparent window region to allow transmittance of an excitation beam to a sample held in the tube.
While the described tube is particularly suited for use in a PCR monitoring apparatus, such as that described in U.S. patent application Ser. No. 08/235,411, abandoned, it can be appreciated that such tubes are also suited for use in other instruments in which detection of light emissions is measured, and particularly those in which such measurement is carried out in a "plate-reader" format.

Fluorescence monitoring device with textured optical tube and method for reducing background fluorescence


A translator fixture for a printed circuit board tester has a pattern of test probes on a base upon which the translator fixture is mounted. The translator fixture includes a plurality of essentially parallel and vertically spaced apart rigid translator plates supported in a fixed position in the translator fixture. Selected patterns of holes are aligned in the translator plates for containing and supporting translator pins extending through the translator plates and for positioning the translator pins for contacting test points under pressure on a printed circuit board supported in an essentially horizontal position between the translator plates. The pins translate electrical test signals between the test points on the printed circuit board and the test probes on the base of the tester. The fixture includes a plurality of blind pins positioned in a top plate of the fixture for non-electrically applying a balancing force to the printed circuit board. The blind pins are positioned in blind holes in the top plate adjacent a surface of the printed circuit board at locations where no test points are located and opposite to a surface on the printed circuit board having the translator pins applying pressure to the test points.

Automatic test equipment for checking printed circuit boards has long involved use of a "bed of nails" test fixture in which the circuit board is mounted during testing. This test fixture includes a large number of nail-like spring-loaded test probes arranged to make electrical contact under spring pressure with designated test points on the circuit board under test, also referred to as the unit under test or "UUT." Any particular circuit laid out on a printed circuit board is likely to be different from other circuits, and consequently, the bed of nails arrangement for contacting test points in the board must be customized for that particular circuit board. When the circuit to be tested is designed, a pattern of test points to be used in checking it is selected, and a corresponding array of test probes is configured in the test fixture. This typically involves drilling a pattern of holes in a probe plate to match the customized array of test probes and then mounting the test probes in the drilled holes on the probe plate. The circuit board is then mounted in the fixture superimposed on the array of test probes. During testing, the spring-loaded probes are brought into spring-pressure contact with the test points on the circuit board under test. Electrical test signals are then transferred from the board to the test probes and then to the exterior of the fixture for communication with a high speed electronic test analyzer which detects continuity or lack of continuity between various test points in the circuits on the board.
Various approaches have been used in the past for bringing the test probes and the circuit board under test into pressure contact for testing. One class of these fixtures is a "wired test fixture" in which the test probes are individually wired to separate interface contacts for use in transmitting test signals from the probes to the external electronically controlled test analyzer. These wired test fixtures are often referred to as "vacuum test fixtures" since a vacuum is applied to the interior of the test fixture housing during testing to compress the circuit board into contact with the test probes. Customized wired test fixtures of similar construction also can be made by using mechanical means other than vacuum to apply the spring force necessary for compressing the board into contact with the probes during testing.
The wire-wrapping or other connection of test probes, interface pins and transfer pins for use in a wired test fixture can be time intensive. However, customized wired test fixtures are particularly useful in testing circuit boards with complex arrangements of test points and low-volume production boards where the larger and more complex and expensive electronic test analyzers are not practical.
As mentioned previously, the customized wired test fixtures are one class of fixtures for transmitting signals from the fixture to the external circuit tester. A further class of test fixtures is the so-called "dedicated" test fixtures, also known as a "grid-type fixture," in which the random pattern of test points on the board are contacted by translator pins which transfer test signals to interface pins arranged in a grid pattern in a receiver. In these grid-type testers, fixturing is generally less complex and simpler than in the customized wired test fixtures.
A typical dedicated or grid fixture contains test electronics with a huge number of switches connecting test probes in a grid base to corresponding test circuits in the electronic test analyzer. In one embodiment of a grid tester as many as 40,000 switches are used. When testing a bare board on such a tester, a translator fixture supports translator pins that communicate between a grid pattern of test probes in a grid base and an off-grid pattern of test points on the board under test. In one prior art grid fixture so-called "tilt pins"" are used as the translator pins. The tilt pins are straight solid pins mounted in corresponding pre-drilled holes in translator plates which are part of the translator fixture. The tilt pins can tilt in various three-dimensional orientations to translate separate test signals from the off-grid random pattern of test points on the board to the grid pattern of test probes in the grid base.
In the past, translator fixtures have been constructed and assembled with a plurality of translator plates made from a plastic material such as Lexan. The translator plates are stacked in the fixture between corresponding sets of spacers aligned with one another vertically to form "stand-offs" spaced apart around the periphery of the fixture. The spacers hold the translator plates in a fixed position spaced apart vertically from one another and reasonably parallel to each other. The translator plates at each level of the fixture have pre-drilled patterns of alignment holes that control the position of each tilt pin in the translator fixture.
Typically, the grid tester will include a bottom translator fixture positioned on a grid base and a second or top translator fixture positioned on a separate grid base located above the bottom fixture. The top fixture is inverted above the bottom fixture so that a printed circuit board under test is sandwiched between the top plates of the top and bottom fixtures. The top translator fixture includes the same components as the bottom fixture so that test points on the top surface of the printed circuit board are tested by the top fixture and the test points on the bottom surface of the printed circuit board are simultaneously tested by the bottom fixture. Both sets of test data are interpreted by a single electronic test analyzer.
A problem exists in this arrangement when a density imbalance of test pins occurs on one side of the printed circuit board due to the locations of the test pads. For example, the top surface of the particular circuit board under test may not have any test points in the center of the circuit board. Test pins are contacting test pads on the board under pressure in the center of the lower surface, and due to the lack of counteracting force from the top fixture, the printed circuit board is bent upwardly during testing, which can damage the unit under test. Each translator pin applies a force of approximately 6 to 8 ounces which when multiplied by the number of pins concentrated in a small area of the unit under test can create an unopposed force up to as much as 500 pounds.
To resolve this problem, stand-offs have been incorporated in the center section of the fixture corresponding to the area where no test points are contacting test pads. This effort has proven unsuccessful, however, resulting in not only continued bending of the printed circuit board, but the entire top fixture bending, resulting in damage to both the circuit board and the test fixture. Accurate test data are difficult to obtain when the unit under test and/or the test fixture is bending.
Consequently, a need exists for a test fixture design which provides a counteracting force to the unit under test in locations on the board where a significant number of test pads are located on only one surface.

Translator fixture with force applying blind pins


The present invention includes a multi-frequency ultrasonic generator coupled to a multi-resonance frequency transducer capable of operating at a plurality of usable resonance frequencies. A controller is coupled to a power amplifier that drives the ultrasonic transducer and is capable of applying power, voltage or current profiles for each of the resonance frequencies to be used during a bonding operation independent of the others.

1. Field of the Invention
The present invention relates to fine wire bonding employing ultrasonic energy applied to the fine wire by a bonding tool held and controlled by an automatic wire bonder. More particularly, the present invention relates to a system and a process of multi-frequency wire bonding wherein a plurality of different resonant frequencies are applied to the same transducer during a single wire bond operation.
2. Description of the Prior Art
Heretofore, ultrasonic transducers used for fine wire bonding were designed and manufactured for use at a single high efficiency resonance frequency. It was generally known that such transducers had one efficient resonant frequency, however, it was not known or appreciated that such transducers could be made which had two distinct resonance frequencies until disclosed in copending U.S. Ser. No. 08/349,251 filed Dec. 5, 1994 for a Multi Resonance Unibody Ultrasonic Transducer by Ali R. Safabakhah and assigned to the same assignee as the present invention.
Heretofore, it was generally known that fine wire bonds made at 60 Khz form in a different manner and display different shear strength characteristics from fine wire bonds made at 120 Khz. There is little or no available data defining the intermetallic structure and shear bond strength for wire bonds made at frequencies that dramatically differ from these frequencies and their closely associated frequencies. Lee Levine summarized the state of art theories concerning wire bonds made at these frequencies in his article "The Ultrasonic Wedge Bonding Mechanism: Two Theories Converge" presented at the International Symposium on Microelectronics (ISHM) Proceedings dated Oct. 24-26 , 1995 at pages 242 to 246.
Summarized, this article disclosed that wire bonds made at high frequencies (e.g. 120 Khz) cause the material at the interface of the wire bond to have high rates of strain hardening accompanied by slight deformation in the initial stages of forming a bond. All things being equal wire bonds made at low frequencies (e.g. 60 Khz) have lesser rates of strain hardening accompanied by greater squash and bond area resulting in stronger shear strength wire bonds.
It would be desirable to provide a system and a method for making fine wire bonds employing two or more resonance frequencies so as to take advantage of all the desirable characteristics which can be achieved using either high or low resonance frequencies. Multi-resonance frequency bonding transducers having two or more efficient resonance frequencies will now permit the incorporation of multi-resonance frequency methods and systems into a new automatic wire bonders as well as permitting retrofitting such systems into existing automatic wire bonders.

Multi-frequency ultrasonic wire bonder and method


A semiconductor device includes a substrate, a gate electrode, an insulating layer, a source electrode, a drain electrode, a semiconductor channel layer, a first passivation layer and a second passivation layer. The gate is formed on the substrate. The insulating layer covers the gate electrode. The source electrode and the drain electrode are positioned on the insulating layer. The semiconductor channel layer is disposed on the insulating layer, and connects the source electrode and the drain electrode. The first passivation layer covers the source electrode, the drain electrode and the semiconductor channel layer. The first passivation layer includes silicon oxide. The second passivation layer is disposed on the first passivation layer. The second passivation layer includes silicon nitride that has a hydrogen concentration of about 2.0×1022 atom/cm3 to about 3.11×1022 atom/cm3.

1. Technical Field
The present invention relates to a semiconductor device. More particularly, the present invention relates to a metal-oxide semiconductor device.
2. Description of Related Art
Metal-oxide semiconductors possess high carrier mobility, and accordingly much attention has been given thereto. As compared to amorphous silicon thin-film transistors (TFTs), metal oxide semiconductor TFTs exhibit better electrical performance. In addition, the method of manufacturing metal-oxide semiconductor TFTs is simpler than that of low temperature polycrystalline silicon TFTs. Therefore, much research has focused on metal-oxide semiconductor TFTs in recent years. Unfortunately, metal-oxide semiconductor materials are very sensitive and unstable so that the semiconductor device cannot achieve satisfactory stability and reliability nowadays. In view of the above, there exists in this art a need of an improved semiconductor device that provides excellent stability and reliability.


Data are input from a geomagnetic sensor that detects magnetic fields in three axial directions, and magnetic field data are measured on the basis of the input data. The measured magnetic field data are sequentially stored, and a determination is made as to whether a plurality of the magnetic field data thus stored lie within a same plane in a three-dimensional orientation space. When it has been determined that the plurality of the magnetic field data lie within the same plane in the three-dimensional orientation space, center coordinates of a circular arc where the stored magnetic field data lie are calculated, as provisional offset values, on the basis of the magnetic field data and in accordance with a predetermined algorithm. Magnetic field data measured after the calculation of the provisional offset values is corrected with the provisional offset values, and an arithmetic operation is performed for determining orientation data on the basis of the corrected magnetic field data.

The present invention relates to generally techniques for performing orientation (more specifically, azimuth) measuring calibration (offset correction) on the basis of orientation measuring data using a geomagnetic sensor. More particularly, the present invention relates to an improved orientation data generation method, orientation sensor unit and portable electronic equipment which, even when data obtained from a three-axis geomagnetic sensor are limited within a particular plane, can perform appropriate calibration to measure a correct orientation (or azimuth).
Portable terminals, such as portable phones, are known, which include a magnetic sensor for detecting geomagnetism and measure orientations on the basis of the geomagnetism detected by the magnetic sensor. The orientations measured in this manner are used, for example, to display a map. Recently, there have appeared portable terminals which are, for example, equipped with a GPS (Global Positioning System) function for detecting a position and has a function for displaying a map based on a current position in accordance with a current orientation (or azimuth) of the portable terminal.
However, in the portable terminals, there exists magnetism leaking from a speaker and microphone provided on the terminal, metal packages of magnetized electronic components, etc. Thus, the magnetic sensors provided in the portable terminals would detect a magnetic filed that comprises a combination of magnetic fields produced from the electronic components etc. within the terminal and the geomagnetism or earth's magnetism. For this reason, a calibration process has to be performed to compensate for error (offsets) caused due to the magnetic fields produced from the electronic components etc. within the terminal. Therefore, in order to perform the calibration process in the conventional portable terminals provided with a two-axis magnetic sensor, it has been conventional for the user to, for example, rotate or turn the portable terminal through 180 degrees so that the portable terminal can gather measured data from the magnetic sensor during the turning movement and estimate offsets on the basis of the measured data.
Among various conventionally-known techniques pertaining to calibration of a magnetic sensor provided in a portable terminal is one disclosed in Japanese Patent Application Laid-open Publication No. 2004-12416. According to the disclosed technique, the portable terminal is turned stepwise, a predetermined angle at a time, and offsets are estimated on the basis of data measured by the magnetic sensor at each of the angles, so that the calibration is performed without depending on the turning speed.
However, even with the technique disclosed in the No. 2004-12416 publication, the user must bother to turn the portable equipment, provided with the magnetic sensor, to perform the calibration process. Namely, although the disclosed technique can achieve some improvement over the traditional techniques, it necessitates the user to perform particular calibrating operation, so that the calibration in the disclosed technique is still as cumbersome to the user as in the traditional techniques. Particularly, where the magnetic sensor is a three-axis geomagnetic sensor, the user has to perform even more cumbersome operation because data of the three axes are required.
In order to perform accurate calibration in the case where the magnetic sensor is a three-axis geomagnetic sensor, it is preferable that data acquired via the geomagnetic sensor lie uniformly within a compass sphere (or orientation sphere); if the acquired data concentrate (i.e., are limited) within a particular plane, the calibration can not be performed in a satisfactory manner.

Orientation data generation method, orientation sensor unit and portable electronic equipment


An information recording device is provided, whereby an inexpensive stepping motor is used to drive a recording disk for recording information, the disk being driven under open-loop control by means of inexpensive digital circuit technology, without employing rotor position detectors or a speed detector, and the rotational accuracy of the recording disk is raised to a level suitable for application, without increasing cost, by constituting the aforementioned step operation (having poor rotational accuracy) inherent in the stepping motor such that certain relationships are formed between the structural parameters of the information recording device and the structural parameters of the motor. In a stepping motor, electrical energy is supplied by switching excitation at a timing synchronized to an input clock, regardless of the load. When this electrical energy is converted to mechanical energy, the moment of inertia of the rotating portion is exploited to a maximum in order to produce smooth rotation.

1. Field of the Invention
The present invention relates to a motor for use in an information recording device, such as an FDD, for example, which accesses information by rotating a disk-shaped recording medium at a constant speed, and in particular, it relates to a spindle motor which drives a recording medium directly.
2. Description of the Related Art
An FDD (Floppy Disk Drive) is used for writing and reading information to and from a disk-shaped information recording medium, known as a floppy disk, used in word processors and personal computers. In the prior art, generally, a brushless DC motor has been employed as the spindle motor for driving rotation of a floppy disk in an FDD. Brushless DC motors present no problems whatsoever in terms of performance or reliability, but since they require rotor position detectors and a speed detector, the motors themselves are unavoidably expensive. Moreover, feedback control of the rotational speed is required in the drive, in order to ensure rotational accuracy, and hence the circuit composition becomes large in size, and such systems have been unable to meet recent demands for cost reduction. In particular, the spindle motor represents a large cost element in the device, and lowering the cost of the spindle motor has become an important objective.
On the other hand, due to the progress of digital electronics technology in recent years, it is possible to drive rotation using an inexpensive stepping motor (a two-phase claw pole motor is especially effective) as a synchronous motor which is synchronized to a clock by means of a simple drive circuit. Furthermore, since a digital drive circuit can be constructed without the inclusion of rotor position detectors or a speed detector in the motor, it has a merit in that the system as a whole can be constructed very inexpensively, and employment thereof is under investigation. However, there is large variation in the rotation of stepping motors due to the step movement of their basic operation, and in particular, in current circumstances, they cannot be employed as spindle motors for information recording devices where high rotational accuracy is demanded.
Furthermore, the use of circuit technology, such as micro-stepping or the like, in order to improve rotational accuracy, is also under study, but this has a drawback in that the cost of the drive circuit becomes extremely high.

Motor for use in information recording device


A control procedure for an automatic transmission, wherein, via a gear range shifter, a change of the gear range both between the forward travel gear range and the reverse travel gear range and between a fast gear mode and a creeper gear mode can be put into action. A control apparatus selects a transmission gear to be engaged, dependent on data, input by an operator with the aid of a gear range shifter for the manual choice of a driving gear area, whereby the gear range shifter possesses at least a D-shifting position for the selection of a forward travel gear range, an N-position for the selection of an idle running position of the automatic transmission and an R-position for the selection of a reverse travel gear range, and that the automatic transmission can be driven in a fast gear mode as well as in a creeper gear mode.

Automatic transmissions have been used for a considerable time in different types of motor vehicles, such as, for example, trucks of medium and heavy weight. Varying from most passenger car transmissions, commercial vehicle transmissions exhibit not only a greater number of gear positions, but include certain gears, which are not provided for use in normal driving operations and are designed to be predominate for starting operations of a loaded vehicle, and/or for use on steep inclines and/or for maneuvering. These additional gears permit very slow movement at a very high torque which is transferred to the gears. In the following, these additional gears are designated as "creeper gears", while the gears used generally for normal driving are termed "fast gears".
Since automatized gear selection apparatuses show in many respects essential advantages in comparison to a manual gear choice made by the driver, these apparatuses are increasingly being installed for heavy vehicles, which employ creeper gears. When this is the case, then, within arm's reach of the driver, at least one gear selection succession is presented, which exhibits three adjustments, namely D, N and R. In the automatized gear range shifter apparatus, in the D-position of the range of gear positions, automatically the respective optimal forward gear is selected without the involvement of the driver or following a displayed confirmation, the driver makes an optional setting of the D-position. When this occurs, the gear to be engaged, for example, is determined with consideration given to: speed of rotation of the motor, motor load, vehicle speed, acceleration, charted motor performance, and possibly additional parameters. In the N-position of the gear range shifter, the transmission is shifted into a neutral position and in the R-position, the reverse gear is engaged, that is to say, the most applicable of various reverse gears is selected.
From his own selection, the driver additionally has a functionally extended gear range shifter by which he can influence an automatic shifting apparatus. This can include, for example, additional shifting positions available to the gear range shifter positions, which can be designated as first, second, third and the like. However, these additional positions considerably diminish the number of the shiftable forward gears. Alternative to this or in addition thereto, the driver often cannot activate, in the given range of gears integrated in the gear range shifter, either an up or down shift. In this situation, the transmission is initiated, to shift one stage up or down from an automatically selected gear. On the other hand, the driver may choose a fully manual mode, for example, by an additional engagement at the M-position of the gear range shifter and shifts the transmission in a method similar to a Tiptronic-Shift wherein the choice is made in a sequential manner and each shifting activation corresponds to a gear change in a chosen direction.
An automatic shifting apparatus in any case cannot reliably discern whether a driver, by his setting of the gear range shifter into the D position of the forward gear range or into the R-position of the reverse gear range, has the intention of moving the vehicle with millimeter precision at creep speed, in order, for example, to carry out an intricate vehicle maneuver or whether the driver plans a normal startup or reverse action. On this account, for the choice of the creep speed mode or the fast mode, it is necessary that an intention of the driver be separately determined and announced.
DE 40 06 653 A1 makes known a shifting apparatus for the semi-automatic shifting of multistage gear change transmissions, which has a gear choice apparatus and a gear range shifter. The said gear range shifter is designed as a rotational shifting means and, besides governing the positions D, N and R, the device can additionally control an M-position, which enables a manual selection of gears. Additionally it is possible that still further positions for shifting programs (not further detailed), namely X1 and X2 can be provided, whereby following the direction of the said rotational shifting means the shift series succession M-D-N-R-X1-X2 becomes available.
Even if, in an extension of the disclosure of DE 40 06 653 A1, an assumption might be made, that the driving programs X1 and X2 are provided for creeper gears in a forward or in a reverse direction, then, in spite of the operational security of the gear range shifter, which passes through a great number of shifting positions, this security is strongly limited, especially in a situation of operation without foresight—that is to say, operation without the driver giving attention to the involved operating elements. In addition, a gear range shifter must be activated to allow exiting from the driving programs X1 or X2 and to obtain the choice of the normal driving position, the same must skip over a great many interposed gear stages.
If, for example, an assumption is made, that X1 represents a creeper gear program for forward movement, a driver finds himself under an obligation to drive a few meters in the direction of a loading ramp or some other targeted position. If, at the desired position and then he would want to precisely position the vehicle, he is obliged to first choose the D-position, in order to subsequently shift through the N-position and the R-position into the X1-position. A smooth switchover between creeper gear and fast gear, in this case, is not possible. In addition, the risk exists of an unforeseen choice of a wrong gear range and especially a gear range in a direction contrary to that desired.
DE 100 16 582 A1 and DE 101 05 749 A1 disclose similar gear range shifters, wherein the positions for forward and reverse creeping gear, however, are to be found at end locations of the rotational scale on different sides and thereby the shift-positions between the reverse travel gear range and the reverse creep gear range are proximal to one another and thus permit safe gear changing. In any case, the switchover between the creep travel gear range for forward and reverse gearing in this instance, requires a shifting movement passing over a number of other gear range. This is quite unfavorable for a maneuvering operation, which often is marked by repeated and quick gear changing between forward and reverse creeper gears.
Giving consideration to the above background, the purpose of the invention is to present a control procedure for an automatic transmission, wherein, by means of a gear range shifter, in a simple and intuitive operational manner for the driver, a change of a gear range can be employed both between the forward gear range and the reverse gear range, as well as between a fast gear mode and a creeper gear mode.
This purpose is achieved by the features of the principal claim, while advantageous embodiments and developments of the invention can be inferred from the subordinate claims.

Control of an automatic transmission by the evaluation of the speed of activation of the gear stage range


A pneumatically operated veterinary medicinal pellet implanter utilizes pressurized air to drive an impeller for dispensing medicinal pellets through a needle on an end of the implanter and into a cavity created by the needle under the skin of an animal to be treated. The pressurized air source may also be utilized to retract the impeller after dispensing of the pellets. The impeller is part of a piston slidingly secured within a pneumatic cylinder. Pressurized air is selectively and alternatingly supplied to the front and rear and rear of the cylinder for advancing the impeller between retracted and extended positions respectively. The pressure of the air supplied to the rear of the cylinder for driving the impeller is reduced relative to the pressure of the air supplied to the front of the cylinder for retracting the impeller.

This invention relates to pellet implanters and in particular to hand held implanters for implanting medicinal pellets and the like in animals.
Pellet implanters are widely used in livestock handling operations to insert solid or semisolid medicaments such as growth stimulating hormones into animals to be treated. Pellets containing growth stimulating hormone are typically injected into the ears of domesticated animals since the ears are commonly discarded in the slaughtering process thereby preventing unabsorbed residues from ending up in food products intended for human or domestic animal consumption.
Typical implanter devices comprise hand held instruments built of a size consistent with the size of the animal. The pellets are normally implanted while an animal is confined in a chute. An ear is grasped in one hand, and an implanter device having a large bore hypodermic needle is used to puncture the hide to enable a pellet dose to be injected between the hide and the next layer of tissue in the ear. The implanting must be done carefully to ensure that the pellets are properly placed and that no pellet remains in the puncture in the hide, which could result in an infection. At the same time, the procedure must be carried out quickly since the animals are not entirely cooperative and may shake their heads to free the held ear.
Further complicating matters is that other procedures may be occurring at the same time as the implanting operation while the animal is confined, such as ear tagging, branding, veterinary inspections or procedures, or the like, which may further excite the animal.
The great majority of implanter devices employ manual gripping force on a trigger and a hand grip of such a device to propel an impeller through a pellet holding device or a magazine to drive the pellets through the needle and into the space formed by operation of the trigger to return the impeller to its retracted position when the trigger is released. With such an arrangement, pellet implanting is complicated by the need to coordinate withdrawal of the needle as the pellets exit the needle. Such complexity of motion coupled with fatigue from using grip strength to eject the pellets can result in mistakes, such as lodging a pellet in the hide puncture or some of the pellets being ejected onto the ground.
A number of implanter devices use multiple pellet dose magazines to hold a plurality of pellet doses. Each pellet dose usually consists of a plurality of small pellets of a measured drug dosage which are positioned in an in-line orientation within a cylindrical chamber of the magazine. The magazine is a strip having a plurality of such chambers arranged in parallel relation, such as by being connected by webs between the chambers. Although some implanters are known to have magazines which advance to the next magazine chamber each time an implant operation occurs, many implanters require manual advancing of their magazines. Such manual advancing of the pellet magazine requires that the person performing the implanting operation remember to advance the magazine after each operation. If the magazine is not advanced, no pellets will be injected.
U.S. Pat. No. 5,522,797 discloses an implanter in which the impeller is manually retracted against the driving force of a spring and then locked in position with a latch mechanism, thereby storing the spring force. Squeezing or pivoting of an associated trigger, releases the latch mechanism which resiliently drives the impeller through an aligned magazine chamber and propels the pellet or pellets in the magazine into the needle. As the needle is withdrawn from the portion of the animal into which it has been inserted, the pellets are urged out of the end of the needle and into the hole formed by the needle. Although the implanter disclosed in U.S. Pat. No. 5,522,797 overcomes many of the problems associated with prior art implanters, the user must still manually retract the impeller after each use which can slow down the process of implanting medicaments in a large number of animals such as may be necessary in large feed lots.
There remains a need for an implanter which permits rapid, successive implantation of medicaments in a large number of animals with minimal manual effort.

Pneumatically operated veterinary pellet implanter