The present invention relates to the field of pull/push exercise with an exercise machine that exercises the abdominal, back and leg muscles with the operator recumbent in the face upwards position. Foot contacts follow an arcuate curve path positioned above the recumbent operator. Resistance is provided for each foot contact where the abdominal muscles of the operator pull the lower leg contact or foot contact towards the operator.

1. Field
The present invention relates to the field of recumbent leg pull exercise apparatus. More particularly, the present invention relates to an exercise apparatus that exercises the abdominal, back and leg muscles with the operator prone on his back whereby the feet follow an arcuate curve with pull/push movement.
2. State of the Art
The benefits of regular exercise to improve overall health, appearance and longevity are well documented in the literature. One of the most difficult muscle groups to exercise is the abdominals. For exercise enthusiasts the search continues for safe apparatus that provides exercise to tone the abdominals without back strain.
Many devices have appeared recently to aid the user in the performance of situps from a prone face-up position with the intent of easing back strain. Situps, even with assistive devices, have low appeal and often the devices find their way to a permanent storage area.
Devices to aid the sit-up movement such as Evans in U.S. Pat. No. 5,120,052, Steinmetz in U.S. Pat. No. 5,419,750 and Brown in U.S. Pat. No. 5,577,987, as just a few, that provide for a recumbent operator to contract the abdominals while raising the upper body with the aid of such device. Another group of abdominal exercise aids such as Boland in U.S. Pat. No. 5,759,138, Conner in U.S. Pat. No. 5,766,118 and Hern in U.S. Pat. No. 6,013,014 start in a seated posture and lean forward against the resistance of an apparatus. Oeglaend in German Pat. No. 3631622 shows an adjustable bench with cable for exercise.
Another abdominal exercise method developed by the Royal Canadian Air Force requires a person to start in a kneeling position on hands and knees, then push his body forward, sliding out along his hands until prone with arms extended. The exerciser then returns to the kneeling position by reversing the sliding action. This is a most difficult exercise and would not be embraced by the average exercise participant.
The simplest kneel-prone-kneel device is the classic exercise wheel. Shiek et al. in U.S. Pat. No. D306,886 shows a pair of wheels rollably attached to a straight rod used for hand grip. Mattox in U.S. Pat. No. 5,261,866 adds elastic tubing to the handles where the knees hold the tubing while the operator is in the push mode to assist in the return mode. A spiral spring is added to the exercise wheel in R.O.C. Pat. 276503 and to a pair of wheels by Barbeau in U.S. Pat. No. 2,821,394.
Semi-recumbent cycles such as Chang in U.S. Pat. No. 6,001,046, Praprotnik in U.S. Pat. No. 4,222,376, Bostic et al. in U.S. Pat. No. D353,422, Dranselka in U.S. Pat. No. 4,262,902 and Jennings in U.S. Pat. No. 4,776,583 show simple bicycle cranks to be operated from a seated position with the hip above or about the same level as the crank.
Another group of cycles intended to be ridden from the recumbent position such as Mousel in U.S. Pat. No. 4,601,464, Dranselka in U.S. Pat. No. 4,739,984, McJunkin, Jr. et al. in U.S. Pat. No. 4,925,184, Shibata in U.S. Pat. No. 5,743,050, Kock in U.S. Pat. No. 4,979,737 and Douglas in U.S. Pat. No. 4,169,591 are simple bicycle cranks attached to a bed by different means.
Recently several semi-recumbent cycles such as Stearns et al. in U.S. Pat. No. 6,077,197, Maresh in U.S. Pat. Nos. 5,707,321 and 5,938,570, Eschenbach in U.S. Pat. No. 5,836,855 and Rodgers, Jr. in U.S. Pat. No. 5,611,758 have added elliptical foot movement to a seated semi-recumbent operator.
Noharan in U.S. Pat. No. 4,717,146, Zibell in U.S. Pat. No. 4,538,804 and Welch in U.S. Pat. No. 4,974,840 show rotary cranks above the operator from adjustable bench positions. Arzonnian in U.S. Pat. No. 4,519,604 shows a rotary crank above a recumbent operator where the crank axis and bench oscillate.
Hess in U.S. Pat. No. 5,279,530, Dixon in U.S. Pat. No. 4,550,908, Zak in U.S. Pat. No. 2,924,214 and McKenzie in UK Pat. No. 403165 show foot contacts that slide away from an operator prone or seated against resistance.
Brentham in U.S. Pat. No. 4,240,627, Davenport in U.S. Pat. No. 4,465,274, Dalebout et al. in U.S. Pat. No. 4,684,126, Berger in U.S. Pat. No. 4,809,976, McBride et al. in U.S. Pat. No. 5,505,679, Shifferaw in U.S. Pat. No. 5,039,088 and Moreillon in Swiss Pat. No. 442103 show swing arms for the feet to operate in a seated position.
One of the top 10 abdominal exercises listed by Club Industry Magazine, May, 2000, page 69, lists number 7 as the xe2x80x9cBicyclexe2x80x9d. The article gives the following directions: xe2x80x9clie on back and lift knees to a 90 degree angle from the floor; Bring the right knee in to the left elbow as the left leg extends; Repeat on the other side; Continue to alternate while keeping abdominals contractedxe2x80x9d. Observation of this exercise shows that the feet can follow an arcuate path instead of a circular bicycle path. The abdominals are exercised because the feet are moved towards the exerciser.
None of the prior art reviewed including samples above address the number 7 exercise with the feet moving along an arcuate curve path while recumbent with knees bent above the upper body operating with resistance. One of the objectives of the present invention is to provide a back and forth movement for the feet where one foot pulls toward the operator against resistance along an arcuate curve path while the other foot pushes away from the upper body along the arcuate path as the leg extends. Another objective of this invention is to provide pull/push apparatus motion which exercises the abdominals, back and leg muscles in a novel manner without back strain.
One objective of the present invention is to provide a pair of lower leg or foot contacts that can be pulled by the abdominal muscles towards the recumbent operator. Another objective of the present invention is to provide means whereby either the ankle, instep or the bottom of the foot can be used by the prone operator for back and forth movement. Another objective of the present invention is to provide a heel support while the foot follows an arcuate path during exercise. Another objective of the present invention is to provide handles for the hands during operation of the exercise apparatus. Another objective of the present invention is to provide an adjustable bench to vary the incline of the back of the operator.
The present invention is intended for a recumbent operator having back downward with knees bent where the feet move along an arcuate curve path located above the torso of the operator. An adjustable bench is provided to support the back while the hip area is supported by a seat. A framework supports the seat, bench and a pair of guide links. The feet are positioned in a pair of foot contacts guided by each guide link to follow an arcuate curve path. An adjustable resistance is imposed upon the guide links.
The lower leg contacts are configured to allow the abdominal muscles to pull one foot towards a recumbent operator against the resistance as the knee bends while the other foot pushes away from the operator as the leg extends. The feet alternately pull and push the lower leg contacts to exercise the leg muscles as well as the abdominals.
In the preferred embodiment, the lower leg contacts are elongated foot contacts pivotally connected to a guide link and a stabilizer link. Both the guide link and stabilizer link are pivoted to the framework about the same height as the hip for each foot contact. An adjustable damping cylinder is pivotally attached to each stabilizer link and the framework. The guide link and stabilizer link are approximately the same length as the upper leg. Therefore, the lower leg and foot contact have only a small amount of relative angular movement during exercise. This allows the foot contact to be in contact with the instep, back of the heel and the bottom of the foot with out twisting the ankle. A bench adjustment is included to vary the incline of the back of the operator.
In an alternate embodiment, the lower leg contact is a foot contact in the form of pedals and foot straps to allow the foot to pull on the guide links. Resistance is by an elastic member adjustably attached to the guide link and the framework of base.
Both the preferred and alternate embodiment are shown with independent guide links whereby the feet can operate opposed or in unison. The following embodiments show how the guide links can be made dependent.
In another alternate embodiment, the lower leg contact becomes an ankle cuff with velcro type material to hold the closing strap. The ankle cuffs are connected to the guide links by cable or rigid pivotable links. Each guide link is pivotally connected to a coupling link which is pivotally connected to a reversing link that is pivotally connected to the framework. Movement of one guide link causes the other guide link to move in the opposite direction. A pair of friction discs are attached to the reversing link with an adjustment knob to add resistance.
In yet another embodiment, the coupling links and reversing link are replaced with a pair of pulleys engaged with cable that is attached to the guide links. Guide links move in opposite directions.
It should be obvious that each embodiment of the present invention can be modified within the scope of the present invention to have either dependent or independent guide link movement.
Each embodiment includes ankle cuffs or foot contacts that move along arcuate curves above the recumbent operator. The length of the curve is determined by the operator. The feet move with a pull/push motion against adjustable resistance. Handles are provided in each embodiment to accommodate the hands of the operator. In any of the above embodiments, the bench can be adjusted to incline the back for the exercise of different muscles.
Each of the embodiments shown contains a minimum number of elements that comprise the linkage to guide the foot contacts along an arcuate curve path. It should be obvious that linkage systems having additional elements can also be used to guide the feet along an arcuate path and are considered within the scope of the present invention.
Each of the embodiments provide pull/push apparatus motion which exercises the abdominals, back and leg muscles in a novel manner without back strain.

Abstract: Handles are provided to support the arms of the operator.


A magnetic rivet retention system for a rivet gun, wherein a magnet is provided in a frame that is engageable with a powered handle. The magnet attracts a rivet and aligns the rivet relative to a punch and die of the rivet gun. The magnet is disposed in an internal chamber in a front bushing. The front bushing is threadably engaged with a back bushing, and both are disposed in a chamber which is provided in a C-frame. A compression spring is also disposed in the C-frame, thereby providing that the rivet gun is spring return.

The present invention generally relates to rivet guns, and specifically relates to rivet retention systems for use with rivet guns.
Rivet guns, such as hydraulic rivet guns, have a head portion which engages a powered body portion. In the case of a hydraulic rivet gun, a C-frame assembly 10 such as is shown in FIG. 1 may engage a hydraulic-powered handle (not specifically shown in FIG. 1). The C-frame assembly 10 includes a C-frame body portion 12 which engages the handle, and is secured to the handle using screws 14.
A threaded bolt 16 is provided, and the threaded bolt 16 includes a head portion 18 and a threaded shaft portion 20. The threaded shaft portion 20 extends through a throughbore 22 which is provided in a back bushing 24 and threadably engages in a front bushing 26. The back bushing 24 and front bushing 26 are disposed in a chamber 28 which is provided in the C-frame 12. A compression spring 30 is also disposed in the chamber 28, generally between the body portion 12 and the handle (not specifically shown in FIG. 1). As such, the rivet gun is hydraulically powered (viz-a-viz the handle) and is spring return (viz-a-viz spring 30).
The C-frame 10 includes spacing 32 for receiving a workpiece. Proximate the spacing 32 is an opening 34 which is in communication with the chamber 28 in which the front bushing 26 is disposed. An end 36 of the front bushing 26 includes a bore 38 for receiving a back end of a punch (not specifically shown in FIG. 1). Specifically, the back end of the punch extends into the opening 34 in the C-frame 12 and extends into the bore 38 in the end 36 of the front bushing 26. A set screw 40 secures the back end of the punch and holds the punch in place relative to the front bushing 26. Proximate the spacing 32 in the C-frame 12 is another opening (not visible in FIG. 1) for receiving an end of a die (not specifically shown in FIG. 1). A set screw 42 is provided to secure the end of the die and hold the die in place relative to the C-frame 12.
In use, a self-piercing rivet is placed inside the punch, and a workpiece is positioned in the spacing 32 provided in the C-frame 12. Then, the handle of the rivet gun is actuated, causing the punch to move toward the die, causing the rivet to set in the workpiece. After the rivet sets, the punch returns to its starting position via the spring force exerted by spring 30.
A problem which exists with regard to rivet guns, such as a hydraulic rivet gun which uses a C-frame as shown in FIG. 1, is the positioning of the rivet in the punch before the gun is actuated. If the rivet is not properly aligned before the rivet gun is actuated, the rivet may not set right during actuation of the rivet gun. To assist in the aligning of rivets, a retaining member (not specifically shown in FIG. 1), such as a urethane ring, may be provided on an end of the punch. However, such retaining members (especially their inside diameters) tend to get worn, thereby losing their effectiveness for precisely positioning rivets.
Furthermore, some rivet guns, such as those rivet guns which us a set of jaws to hold a rivet for broaching, are not practical for some applications. For example, some applications, such as roofing applications, provide that a workpiece is multiple-layered, having glue disposed between at least two of the layers. During riveting, glue may squirt onto the rivet gun, thereby diminishing the effectiveness of the gun during subsequent operation.

Magnetic rivet retention system for a rivet gun


A thin film formation method includes the deposition step of forming a dielectric thin film consisting of many elements. In the deposition step, first- and second-layer thin films are deposited as lower and upper layers on an underlayer, and at least one of the thin films is crystallized to form the dielectric thin film. The first-layer thin film closer to the underlayer is deposited with a larger composition of at least one kind of constituent element of the thin film than stoichiometric composition to allow for diffusion outside the film.

1. Field of the Invention
The present invention relates to a method of manufacturing a semiconductor device and, more particularly, to a method of manufacturing a thin film used for an electronic component, a semiconductor integrated circuit, and the like.
2. Description of the Prior Art
At present, thin film formation techniques are indispensable to techniques of manufacturing electronic components and, particularly, semiconductor integrated circuits.
These techniques are more important for memory elements or memory integrated circuits using ferroelectrics or high dielectrics as a capacitor film material.
In a conventional Si-LSI process, a single-crystal Si substrate is used as a substrate. An Si oxide film and an Si nitride film are formed as ferroelectric films on the substrate, and a poly-Si film is stacked as an electrode film. These film formation techniques realize precise film thickness control and high-speed deposition.
At present, deposition techniques such as CVD and sputtering used in the Si-LSI process have been developed for ferroelectric and high-dielectric thin films which receive a great deal of attention as new capacitor dielectric films. Well-known solid materials exhibiting ferroelectric properties are composite metal compounds having a perovskite crystal structure and a layered perovskite crystal structure. As the composite metal compound having the perovskite crystal structure, lead zirconate titanate (PZT), BaTiO.sub.3, SrTiO.sub.3, and the like are known. As the composite metal compound having the layered perovskite crystal structure, SrBi.sub.2 Ta.sub.2 O.sub.9, PbBi.sub.2 Ta.sub.2 O.sub.9, and the like are known.
Many examples employing the above-described CVD and sputtering, and the sol-gel method as the deposition method have been reported. One example is disclosed in Japanese Unexamined Patent Publication No. 6-57411, and its technique will be described with reference to FIG. 1.
As shown in FIG. 1, a conductive film 123 is formed on a substrate 121 directly or through a buffer layer 122. A dielectric underlayer 124 is formed on the conductive film 123, and a perovskite oxide dielectric thin film 125 is formed on the dielectric underlayer 124. A metal film formed on the thin film 125 is processed to form an upper electrode 126.
C. K. Kwock et al. deposited a PZT thin film on a Pt underlayer by RF sputtering at a substrate temperature of about 200.degree. C. (Material. Research Society Symposium Proceed ings vol. 200. 1990. p. 83). After the PZT thin film was sputter-deposited on the Pt underlayer heated to a certain temperature, the resultant structure was annealed in a furnace to obtain perovskite crystals. In this case, it was reported that lead diffused outward from the film in high-temperature annealing, and the percent in lead loss from the film was proportional to the annealing temperature (see FIG. 2).
The present inventors also confirmed by experiments that constituent elements diffused into an underlayer even when SrBi.sub.2 Ta.sub.2 O.sub.9 (to be referred to as SBTO hereinafter) which has been receiving a great deal of consideration as a dielectric film material for a ferroelectric memory, was deposited. FIGS. 3A to 3D show the results of energy spectral analyses by energy dispersive X-ray spectroscopy (EDX) when an SBTO film was formed on a Pt/Ti film by magnetron RF sputtering without heating a substrate, and the resultant structure was annealed in oxygen at 800.degree. C.
In this case, the deposition film thickness was about 200 nm. The deposition underlayer was constituted such that a 500-nm thick Si oxide film was formed on an Si substrate, and a 20-nm thick Ti film and a 200-nm thick Pt film were formed on this Si oxide film.
Analyses were performed for an annealed structure and a structure not subjected to annealing. Analyzed portions were two portions, i.e., the SBTO film and underlayer (metal film) of each structure.
In deposition, no peak representing the presence of Bi element contained in the SBTO film was observed in the underlayer (metal film), as shown in FIG. 3B.
After annealing at 800.degree. C., the peak of the Bi element contained in the SBTO film appeared in the underlayer (metal film), as shown in FIG. 3D, which represented that the Bi element diffused from the SBTO film to the underlayer upon annealing.
In a film structure shown in FIG. 3A, a film immediately after deposition without heating a substrate consisted of crystals including many amorphous crystals or defects, so it did not exhibit ferroelectric properties or its properties were very poor. In FIG. 3C, crystallization was sufficiently performed upon heating to obtain desired ferroelectric properties. Therefore, the annealing process is necessary.
However, constituent elements contained in the dielectric thin film also diffuse during crystallization. Atoms which do not contribute to the crystal growth are precipitated in the film or diffuse outside it. "Elements which do not contribute to the crystal growth" means both "elements excessive in constituting crystals" and "elements which diffuse before being entrapped in crystals". When an SBTO film is used as a dielectric thin film on a Pt/Ti underlayer, it is observed that Bi greatly diffuses to the underlayer.
FIG. 4 shows an example of measuring ferroelectric properties obtained when an SBTO film is sputter-deposited on a Pt/Ti underlayer on an Si oxide film and annealed in the oxygen atmosphere at 800.degree. C., and then an upper Pt electrode is arranged to form a capacitor structure. The composition ratios of Bi to Sr before and after annealing which are examined by the ICP (Induced Coupled Plasma) analysis are 2.1 and 2.0, respectively, which are almost stoichiometric composition ratios.
The polarization characteristics, however, are almost 10% the reported value (2Pt=15 to 20 .mu.C/cm.sup.2), and are not preferable. This is because many Bi components diffuse at the interface region with the underlayer before being entrapped in crystals in crystal growth, resulting in Bi loss at the interface with the underlayer, or because Bi necessary for crystallization decreases upon diffusion of Bi to the underlayer, resulting in a condition with many defects or a region in a condition wherein a desired crystal structure does not satisfactorily grow.
As described above, in the method of depositing a composite metal oxide as a dielectric thin film, when the film is deposited without heating a substrate to a high temperature, the constituent elements of the dielectric thin film diffuse outward or into an underlayer. As a result, the composition ratio of the elements of the dielectric thin film crystallized by annealing undesirably changes. In particular, the distribution at the interface between the surface region of the film and the underlayer is disadvantageously greatly influenced.
When the film is deposited while heating the substrate, if an element having a high vapor pressure is contained as a constituent element in film formation, a crystalline thin film is difficult to grow, while ensuring the stoichiometric composition ratio. Especially, the composition disadvantageously shifts at the interface region with the underlayer. In addition, the constituent elements of crystals are lost to interfere with the film growth. Even if a dielectric thin film serving as a buffer layer and having dielectric properties and the like which hardly influence target properties is deposited as an intermediate layer on an underlayer on which the dielectric thin film having necessary properties should be deposited, the film quality is degraded during deposition unless the respective deposition temperatures are properly controlled.
In Japanese Unexamined Patent Publication No. 6-57411 shown in FIG. 1, as the dielectric underlayer 124 of the perovskite dielectric thin film 125 consisting of ABO.sub.3 (A and B are perovskite crystals at A and B sites as atom positions generally designated), a dielectric thin film consisting of A'B'O.sub.3 or B'O.sub.3 using the same constituent elements is effective.
If this underlayer is formed of a dielectric, the composition ratio of the elements of the formed film must exhibit dielectric properties. That is, when a dielectric layer is formed on the dielectric underlayer 124 so as to contact the dielectric underlayer 124 deposited with a precise composition as a dielectric, if the formation temperature is high, or if energy to promote generation of point defects is applied to promote diffusion of elements, diffusion of the elements of the underlayer to the lower conductive film 123 (lower electrode) is difficult to suppress, resulting in poor film properties.
In Japanese Unexamined Patent Publication No. 6-57411, the buffer layer 122 is arranged between the conductive film 123 and the substrate 121 to prevent mutual diffusion between the substrate and the dielectric film. Even with this arrangement, diffusion of the elements of the dielectric layer to the conductive film 123 is difficult to prevent.

Thin film formation method for ferroelectric materials


An image forming apparatus includes an image forming unit, an image heating unit, an air circulating unit, and a filter. The air circulating unit circulates air around the image heating unit. The filter absorbs a volatile organic substance in an air circulation path defined by the air circulating unit.

1. Field of the Invention
The present invention relates to an image forming apparatus, such as a copying machine, a printer, and a facsimile.
2. Description of the Related Art
New recording media have been developed due to market demand. Therefore, there is a desire to use such new recording media in an electrophotographic image forming apparatus.
When such new recording media are used in an electrophotographic image forming apparatus, heat that is applied from a fixing device has no influence on the human body, but a very small amount of volatile-organic-compound-containing gas may be generated.
A proposal for reducing the amount of volatile-organic-compound-containing gas that is discharged out of the image forming apparatus has been made.
Japanese Patent Laid-Open No. 2004-240270 discusses disposing a filter, which absorbs volatile-organic-compound-containing gas, in an exhaust duct of an image forming apparatus.
However, when the filter is disposed in the exhaust duct that exhausts heat of the image forming apparatus as discussed in Japanese Patent Laid-Open No. 2004-240270, the filter causes exhaust back pressure. Therefore, the heat in the image forming apparatus may not be sufficiently exhausted.
In addition, in the above-described example, since the volatile organic compound is removed by passing air through the filter only once, the efficiency with which the volatile organic compound is removed can still be improved.


A method for monitoring the operability of a mechanical power transmission path between an actuator of an automated transmission and a shift element of the transmission. The selection of the gear step to be engaged takes place via a control unit, and before the selection process a matching movement in the selection direction is performed with the shift element until a reference point has been detected by the control unit.

1. Field of the Invention
The present invention relates to a method for monitoring the operability of a mechanical power transmission path between an actuator of an automated transmission and a shift element of the transmission.
2. Description of the Related Art
Transmissions for motor vehicles are already known in many forms. A transmission has so far mainly been understood as a manual shift transmission where, in a motor vehicle equipped with such a transmission, the driver selects the shift path and executes the shift process manually through the shift lever. Apart from those manually-actuated transmissions, automated transmissions have meanwhile also become known, where the selection and shift process of the selected gear steps occurs, for example, with control programs that operate actuators that are provided in the transmission. By the position of the shift lever, which, for example, is operated in an H-pattern, the driver of a motor vehicle having such a manual transmission system is provided with information about in which gear the transmission is engaged at that moment. If, for example, a fault occurs in the power transmission path between the shift lever and the internal actuation elements within the transmission, such as the breakage of a gear selector rod, the driver can determine that from the shift lever during the selection or shift process.
When in the case of an automated transmission the selection process of the shift path to the gear step that is to be engaged does not function, due, for example, to a fault in an actuation element of the transmission, that can lead to the previous gear remaining engaged instead of a new target gear step. To survey the selection operation and the shift operation through, for example, two electric motors in an automated transmission, movement path measurements can be obtained from those motors, but they do not enable detection of a fault in the mechanism downstream of the motors.
The present invention relates to providing a method for monitoring the operability of a mechanical power transmission path between an actuator of an automated transmission and a shift element of the transmission, so that a defect in the power transmission path can be detected before a shift process is carried out.
The invention provides a solution to that task in the independent claims. Advantageous embodiments of the method are described in the additional claims.
In accordance with the invention, a method is provided for monitoring the operability of a mechanical power transmission path between an actuator of an automated transmission and a shift element of the transmission, wherein the selection process of the gear step that is to be engaged is performed by the actuator through a control device, and wherein before a selection process a matching movement in the selection direction is carried out with the shift element until the control unit detects a reference point.
In accordance with the invention the method provides for carrying out a matching movement in the selection direction if, in general, a fault condition is encountered in such a way that a certain probability exists of a defect in the power transmission path. Such a defect can be, for example, a break in the power transmission path, which upon measurement of the movement path of the actuator cannot be detected from the actuator itself, for instance by recording the torsion angle increments of the actuator. If the fault condition is encountered, a matching movement in the direction of a selection movement is carried out by the actuator that is operated with the shift element, until the control unit detects a reference point, so that the probability for the defect can be negated.
Therefore, the invention provides that the reference point is a stop at which the shift element stops in the selection direction, and that the stop is detected by the control unit. The stop can be a stop within the transmission, for example in the neutral path of the transmission. When the shift element meets with the stop, the control unit detects that the stop is encountered, wherein for that purpose, for example, the rotational speed of the actuator can be monitored for the selection process so that a drastic reduction in the rotational speed of the actuator indicates that it has reached the stop. Additionally, an increase in the voltage and/or the current for controlling the actuator can be monitored.
Based on an advantageous embodiment in accordance with the invention, the control unit monitors the sum of the kinetic energy of the actuator and the electric energy fed to the actuator, and compares it with a reference value of elastic energy that can be absorbed by the power transmission path, and carries out the alignment movement after the reference value has been exceeded.
When the actuator in the form of an electric motor is supplied with current, the rotor shaft of the electric motor is accelerated so that it has a certain kinetic energy. After current flow to the electric motor ceases, the motor causes a force to be introduced into the power transmission path, in, for example, a mechanism downstream of the electric motor, with which the force is transmitted to the shift element that is in the form of, for example, a shift finger. When the shift element in the transmission rests against a stop, continued running of the electric motor leads to a winding up or tensioning of the mechanism downstream of the electric motor. A monitoring of the sum of the kinetic energy of the actuator and the electrical energy fed to the actuator enables a determination as to whether that sum exceeds a reference value or threshold value, and that still can be absorbed within the framework of an elastic deformation of the mechanism that is downstream of the electric motor without being damaged.
Once that sum reaches the reference value, the method in accordance with the invention provides for a alignment movement, which leads to the determination of whether the mechanism that is downstream of the electric motor is still functional, which can be recognized by the control unit by the fact that the shift element actuated by the mechanism has reached a stop whose reference position is known, or whether that is not the case.
Since the reference value is not set so high that the mechanism downstream of the electric motor incurs permanent damage, the fact that this reference value has been reached does not lead to such damage. In accordance with the method, there is also provided a proceeding when the above-described sum not only reaches the reference value, but substantially exceeds it. Upon exceeding the reference value beyond a previously established threshold value, the control unit can issue an error message and indicate that to the driver of the motor vehicle with the automated transmission.
Due to the fact that the motor vehicle with the automated transmission is exposed to varying temperature conditions, which can be substantially influenced by, for example, an internal combustion engine that is coupled with the transmission, the invention also provides for a feature based on which the reference value is determined as a function of the temperature in the region of the power transmission path.
An increase in the measured temperature can therefore lead, for example, to a lowering of the reference value, since the mechanism that is downstream of the electric motor is exposed to higher temperature stress, and, thus, the energy that can be absorbed within the framework of elastic deformation without a permanent deformation is reduced.
Since the power transmission path in the form of a mechanism that is downstream of an electric motor must experience less mechanical stress at elevated temperatures, the method in accordance with the invention provides that the electrical energy that is fed to the actuator is limited as a function of the kinetic energy of the actuator and the temperature in the region of the power transmission path.
Finally, the invention also provides that the electrical energy that is fed to the actuator is reduced after detecting a stop, so that the control voltage applied to the actuator, or the load current fed to the actuator, is clearly reduced after the control unit detects the stop.
The control unit can continuously calculate the above-mentioned sum of kinetic energy and electrical energy. The electrical energy can be limited as a function of the kinetic energy and, for example, the temperature can be limited to a maximally permissible value. During a selection process, the highest motor rotational speed value that is associated with the highest kinetic energy of the rotor shaft is taken into consideration, and the electrical energy is limited in relation to it.
Test series can help determine which energy sum can be introduced into the selection mechanism for a permissible elastic deformation of the selection mechanism, which can also occur as a function of the temperature in the region of the selection mechanism. When that energy sum has been reached, there exists a certain probability for a defect in the selection mechanism. With a reference movement or a alignment movement for the purpose of detecting a stop in the selection direction, one can determine whether or not a defect exists. The degree of confidence in the result can be increased through repetition. If the energy sum should clearly exceed the reference value, the possibility of lasting damage is higher, and it can be provided that the control unit gives corresponding error information to the driver of the motor vehicle, in addition to bringing about a reference movement, or as an alternative to a reference movement.
Based on the invention, a method is also provided for monitoring the operability of a mechanical power transmission path between an actuator of an automated transmission and a shift element of the transmission, wherein the selection process for the gear step that is to be engaged is performed with the actuator through a control unit, wherein the threshold force that leads to a permissible elastic deformation of the power transmission path is established, and wherein before or upon reaching the threshold force an overload clutch that is provided in the power transmission path is opened.
An overload clutch can be provided in the power transmission path between the actuator and the automated transmission, which disengages upon reaching a certain load threshold and thereby interrupts the power flow between the actuator and the shift element. Damage to the power transmission path is thereby prevented.
After the overload clutch has been disengaged in order to prevent damage, it can be engaged again, whereupon a alignment movement in the selection direction is performed with the shift element before a selection process, until the control unit detects a reference point. This start to the reference point is used on the one hand to determine that the mechanism downstream of the actuator was not damaged, and on the other hand to also perform a referencing process of the torsion angle increment sensors of the actuator. This also clarifies that the engagement of the overload clutch does not have to occur at a true angle or a true path. Upon engagement of the overload clutch, it acts like a positive-locking connection.
In test series, the energy that the mechanism that is arranged after the actuator requires to actuate the shift element of the transmission within the framework of elastic deformation without lasting damage can be determined. That energy can also be determined as a function of the temperature in the region of the power transmission path. The power peak occurring upon reaching the respective energy is determined, and the overload clutch is designed in such a way that it disengages at a power threshold below the tolerable power poak. When the sum of the kinetic energy of the actuator and the electrical energy fed to the actuator exceeds the disengagement threshold of the overload clutch, the overload clutch disengages and in that way avoids damage to the power train.
Upon engagement of the overload clutch, an appropriate referencing process is performed, such as the one described above. By reaching a stop in the transmission, a positive determination is made that the power transmission string was not damaged, and thereby the torsion angle increment measurement can also be adjusted.
The invented method is provided in particular for utilization as a shift safety device against a shift between the forward motion direction and the reverse motion direction of the automated transmission.

LuK Lamellen und Kupplungsbau Betelligungs KG


A polishing pad and a method for polishing semiconductor wafers. The polishing pad includes a polishing layer and a rigid layer. The rigid layer adjacent the polishing layer imparts a controlled rigidity to the polishing layer. The resilient layer adjacent the rigid layer provides substantially uniform pressure to the rigid layer. During operation, the rigid layer and the resilient layer apply an elastic flexure pressure to the polishing layer to induce a controlled flex in the polishing layer to conform to the global topography of the wafer surface while maintaining a controlled rigidity over the local topography of the wafer surface.

1. Field of the Invention
The present invention relates to a three layered polishing pad and a method for polishing and planarizing irregular surfaces, such as semiconductor wafers.
2. Background of the Invention
Semiconductor wafers are cut from ingots of single crystal silicon which are formed by withdrawing a seed from a silicon melt rotating in a crucible. The ingot is then sliced into individual wafers using a diamond cutting blade. Following the cutting operation, at least one surface of the wafer is polished to a relatively flat, scratch-free surface. Due to manufacturing irregularities, however, the thickness of the wafers equally vary. For example, the thickness of six inch wafers may range from 0.650 to 0.700 mm. Furthermore, the thickness of each wafer may vary by as much as 3.0 um across the wafer.
In the manufacture of integrated circuit semiconductor devices, the polished surface area of the wafer is first subdivided into a plurality of locations at which integrated circuits (IC) are formed. A series of wafer masking and processing steps are used to fabricate each IC. Thereafter, the individual ICs are cut or scribed from the wafer and individually packaged and tested to complete the device manufacture process.
The masking and processing steps during fabrication may result in the formation of topographical irregularities on the wafer surface. For example, topographical surface irregularities are created after metallization, which includes the sequence of blanketing the wafer surface with a conductive metal layer and then etching away unwanted portions of the blanket metal layer to form a metallization interconnect pattern on each IC.
The height differential (h) between the metal interconnect and the wafer surface where the metal has been removed results in a wafer surface irregularity commonly referred to as a step. On a very large-scale integrated (VLSI) IC, the step features can average 1 um or more in height and have a lateral surface dimension ranging from approximately 1 um to more than 1 mm. A typical VLSI chip on which a first metallization layer has been defined may contain several million steps, and the whole wafer may contain several hundred ICs.
Referring to FIG. 1, a perspective view of a processed semiconductor wafer 10 is shown. The wafer 10 includes a plurality of ICs 12. Each IC 12 includes a center region 14 which usually includes a high degree of device integration, and an outer periphery region 16 which typically has a relatively lower degree of device integration. Each IC is separated from the other ICs by scribe lines 18.
Referring to FIG. 2, a cross section of the wafer of FIG. 1 taken along line 2'--2' is shown. The cross sectional view of the wafer 10 illustrates several characteristics which are typically found on a wafer after Metallization. First, the thickness of the wafer is not uniform. The center region 30 of the wafer 10 has a thickness of T.sub.1 which is thicker than the peripheral regions 32 of the wafer having a thickness T.sub.2. It should be noted that wafer 10 is merely illustrative, and that the regions at which the thickness of the wafer may vary may occur at different portions of the wafer.
Second, a higher percentage of the center regions 14 of each IC 12 are elevated due to the high degree of device integration in these regions. In contrast, a substantially lower percentage of the peripheral regions 16 of each IC are lower with respect to the center regions 14 due to the lower degree of device integration. Hereinafter, the center regions 14 and peripheral regions 16 are referred to as high density regions 14 and low density regions 16 respectively.
Third, the high degree of device integration in the high density regions 14 creates a large number of steps 34 on the surface of the wafer. The gaps between each step 34 in the high density regions 14 generally have a lateral dimension of one micron or less. In contrast, the low degree of device integration in the low density regions 16 creates a relatively smaller number of steps 34 in these regions. The gaps between steps in the low density regions 16 may range from 1 micron to one millimeter, and the gaps between two high density regions 14 may range from 0.5 to 3.0 millimeters in lateral dimension. (Note, the thickness disparity (T.sub.1 vs. T.sub.2), the height and lateral dimensions of the steps 34, and the gaps between the steps relative to the dimensions of the wafer are greatly exaggerated for clarity.)
Fourth, a dielectric layer 19, such as silicon dioxide, is deposited over the wafer surface by a chemical deposition or another known technique. The dielectric layer 19 assumes the same topography as the underlying wafer surface.
Referring to FIG. 3, an exploded view of a high density region 14 between lines 3'--3' of the cross section of the wafer 10 of FIG. 2 is shown. This exploded cross section view illustrates that wafer topography irregularities are also created by trench isolation, which is common technique used in VLSI circuits to prevent latch up and to increase device density. The exploded cross section view of FIG. 3 includes an n-channel device 40 and a p-channel device 42 built in an n-well 43 in wafer 10. A dielectric trench 44 separates devices 40 and 42 in the substrate 10. A first metallization layer 45 electrically couples devices 40 and 42. Dielectric layer 19 covers the top surface of the devices 40 and 42 and the topography of the wafer above the trench 44 is raised above the remainder of the wafer surface.
The lack of planarization due to metallization and trench isolation on the wafer surface can cause significant problems during wafer fabrication. For example, the steps 34 on the high density and low density regions 14 and 16 respectively may cause focusing problems during optical lithography. Since the dielectric layer 19 which is deposited over the wafer surface after metallization and trench isolation assumes the irregularities of the wafer surface, the lack of surface planarization may make it difficult or impossible to lay down subsequent layers of metal interconnect, thus limiting the number of metallization layers that can be practically used in device manufacture.
Polishing the dielectric layer 19 on the surface of a wafer after metallization and/or other selected stages in the fabrication process is one known method for planarizing wafer surface topography. Since the dielectric layer 19 covers the surface of the wafer, it provides a layer of uniform composition for planarization.
Referring to FIG. 4, a cross section of a standard wafer polishing apparatus is shown. The polishing apparatus 20 includes a platen 21 for supporting a polishing pad 23, a wafer chuck 24 having side walls 25a and 25b and a resilient pad 2 6. The back of the unprocessed surface 27 of a wafer 10 rests against resilient pad 26 and is positioned by side walls 25a and 25b in wafer chuck 24. The processed surface 28 of the wafer is thus in contact with and exposed to the polishing pad 23 during operation.
The platen 21 rotates about a first axis 29a. The wafer chuck 24 and wafer 10 rotate about a second axis 29b which is substantially in parallel with axis 29a. A member 61 moves the rotating wafer chuck 24 horizontally across the surface of the polishing pad 23. As wafer 10 is rotated, its processed surface 28 moves across the polishing surface of the polishing pad 23.
During operation, a slurry of colloidal silica or another suitable abrasive is introduced between the dielectric layer on the wafer 10 and the polishing pad 23. The reaction between the slurry and the dielectric layer under the polishing motion results in the chemical-mechanical removal of the dielectric on the wafer surface. Ideally, the dielectric material would be typically removed faster over the high density regions 14 than in the low density regions 16 on the wafer surface. Thus, the topography of the wafer surface would be polished and planarized. In actuality, less than ideal results are obtained using polishing pads known in the art today.
Referring to FIG. 5, a two-layered polishing pad according to the prior art is shown. The pad 36 includes a resilient layer 37 and a polishing layer 38 covering the resilient layer. When placed in contact with a processed surface of the wafer, the polishing layer maintains contact with the high density regions 14. The polishing layer 38 bridges the gaps in the high density regions 14 since lateral distance of the gaps in the high density regions 14 are in the order of 1 micron.
The resilient layer 37 however forces the polishing layer 38 into the low density regions 16 so that the polishing layer 38 conforms to the local topography of the low density regions 16.
The two-layered polishing pad 36 has a number of deficiencies. The materials for the polishing layer 38 known in the art, such as urethane, are not rigid enough, causing the polishing layer 38 to conform generally to the low density regions 16 and to any gaps which are greater than approximately 1 mm in lateral dimension. As a result, the rate at which the polishing pad 36 removes dielectric material from the high density and low density regions 14 and 16, respectively, or any gaps with a lateral dimension of 1 mm or greater, is substantially equal. Accordingly, the pad of FIG. 5 has a leveling length, which is defined as the lateral distance over which the pad will maintain its rigidity over a local portion of the wafer, of approximately 1 mm, which is too short and does not result in the planarization of the wafer surface.
The lack of rigidity of the polishing pad 36 also results in the uneven rate of dielectric material removal over regions of different device integration density. Since the polishing force in both high density and low density regions are substantially equal, the polishing pressure applied to the low density regions is greater than the polishing pressure in the high density regions because there is less surface area of the polishing pad in contact with the wafer topography in the low density regions. As a result, the dielectric material is removed faster in the low density regions 16. The uneven removal rate may lead to excess removal of the dielectric layer 19 on the wafer surface, which may destroy the underlying devices.
Furthermore, the polishing layer performs the dual role of polishing the wafer surface and providing a rigidity to the polishing surface of the pad. Therefore, the mechanical properties of the two layer pad are vulnerable to change due to wear and use of the pad. The two layered polishing pad thus exhibits changes over time in its ability to planarize. This is undesirable because the mass production of wafers requires consistency.
Published European patent application, No. 0223920, discloses a method of polishing semiconductor wafers using a chemical-mechanical polishing technique with an improved polishing slurry. The polishing pad material is made of a polyester material is firm enough so that it does not deform under the polishing load.
Semiconductor manufacturers also use other methods for wafer planarization, such as spin on glass (SOG). In the SOG procedure, a sacrificial layer of glass is spun onto the dielectric layer 19. Ideally, the glass flows and fills in the low density regions 16 and gaps prior to curing. Thereafter, the glass layer and dielectric layer 19 are etched back at the same rate, leaving behind a planar wafer surface.
The SOG technique also has major deficiencies. First, the glass is only capable of filling gaps up to approximately 40 microns. Gaps of 40 microns or greater are only partially filled by the glass. Second, the etch rates of the glass and the dielectric are not identical. Accordingly, the larger gaps such as the low density regions 16 remain unfilled and therefore are not level with the high density regions 14, and the surface remains non-planar after etch back.
The failure of prior art planarization techniques significantly reduces chip yields and greatly increases IC manufacturing costs. The failure to planarize the wafer surface limits the number of subsequent metallization layers that can be used to build the ICs on the wafer. Lastly, a non-planar wafer surface limits the critical dimension, which is defined as the smallest feature of on the wafer surface, such as the geometrical gate length, which can be fabricated on the wafer surface. Smaller feature sizes require a lithography tool with a shallower depth of field and this requires better planarization of the wafer surface.

Polishing pad and method for polishing semiconductor wafers


A relatively simple method for providing relatively close spacing between the emitter mesa and the base ohmic metal of a heterojunction bipolar transistor (HBT) on a relatively uniform basis. An emitter and base layer are epitaxially grown on a substrate. An emitter mesa is patterned with an i-line negative photoresist using conventional photolithography. Baking before and after exposure is used to form a resist pattern with a re-entrant profile having about a 0.1 .mu.m resist overhang. The emitter layer is then etched with a wet etch and or isotropic dry etch to expose a portion of the base ohmic metal to make contact with the base. A second layer of an i-line negative photoresist is applied over the first photoresist. The second layer is used to pattern the base ohmic metal mask. The base ohmic metal is deposited by evaporation. The resist is stripped from the emitter mesa and the non-base ohmic metal regions which lifts the metal deposited on the resist leaving the metal in the base ohmic metal regions, aligned to the emitter mesa at a uniform spacing.

1. Field of the Invention
The present invention relates to a method for fabricating integrated circuits and more particularly to a method for achieving controllable spacing between the emitter mesa and the base ohmic metal of a heterojunction bipolar transistor (HBT).
2. Description of the Prior Art
Heterojunction bipolar transistors (HBT's) are known in the art. Examples of methods of fabricating such HBT's are disclosed in U.S. Pat. Nos. 5,159,423; 5,272,095; 5,411,632; 5,446,294; 5,468,659; and 5,485,025. Such HBT's normally include a substrate, as well as epitaxially grown collector, base and emitter layers known to be formed by various methods, including molecular beam epitaxy. Such HBT's are normally formed with an emitter mesa, normally formed by well-known photolithography techniques. Known metalization techniques are used to form ohmic metal contacts on the emitter mesa, as well as the base.
It is known in the art that the base ohmic metal spacing to the emitter mesa is relatively critical to the device performance. In particular, if the base ohmic metal is deposited too close to the emitter mesa, a potential leakage path between the base and the emitter can be created, resulting in degradation of the gain (.beta.) of the device. Should the spacing between the base ohmic metal and emitter mesa be too large, the parasitic base resistance of the device will be too large, thereby degrading the performance of the HBT.
Various methods are known for controlling the spacing of ohmic contacts for various integrated circuits, including HBT's. Various methods rely on self-alignment of the base ohmic metal and the emitter mesa. For example, one known self-alignment method relies on etching the emitter with an emitter photoresist layer and retaining that layer during the patterning of the lift-off of the photoresist for the base ohmic metal. However, it is known that the spacing between the base ohmic metal and the emitter mesa is not controllable with such a method.
Another known method for controlling the spacing between the base ohmic metal and the emitter mesa relies on so-called spacer technology, frequently used in silicon processing. In that method, the emitter mesa is an anisotropically etched. After the emitter mesa is formed, a spacer layer is deposited and anisotropically etched. A base ohmic metal is patterned and lifted off by conventional techniques, except from over the spacer and emitter. The removal of the base ohmic metal from the spacer and emitter is known to done by ion milling. Unfortunately, damage from the anisotropic etches and the high-defect density usually encountered in the ion milling process limit the usefulness of this type of spacer technology.
Other methods for controlling the spacing between the emitter mesa and the base ohmic contacts are disclosed in U.S. Pat. Nos. 5,124,270; 5,159,423; 5,411,632; 5,446,294; 5,468,659; and 5,486,483. U.S. patent application Ser. No. 08/676,697, filed on Jul. 10, 1996, entitled "Method of Fabrication High Beta HBT Devices", by Lammert, assigned to the same assignee on the present invention now U.S. Pat. No. 5,804,487, also discloses a method for controlling the spacing of the base contacts relative to an emitter mesa. Although the methods described in the patent application and patents do provide some control of the spacing between the base ohmic metal and the emitter mesa, the methods disclosed are relatively complex and involve quite a few process steps.

Self-aligned base ohmic metal for an HBT device cross-reference to related applications


Performing power saving control which can be inherited and standardized easily, and which keeps power devices from having to become larger is made possible. A current In flowing through an electrical path is detected as a voltage Vs by a current detection section, and is outputted as a voltage Vout by an amplifying section. When a level corresponding to the voltage Vout exceeds a limit level, a power limit detection section outputs a power limit detection signal. When a controller receives the power limit detection signal via a detection signal holding section, the controller outputs a throttle control command signal. When a chip set receives the throttle control command signal, the chip set initiates throttle control that lowers the clock frequency of a CPU. The present invention may be applied to laptop personal computers.

1. Field of the Invention
The present invention relates to an information processing apparatus and method, as well as a program, and more specifically to an information processing apparatus and method, as well as a program in which performing power-saving control of the information processing apparatus which keeps a power device from having to be made larger and which can be inherited and standardized easily is made possible.
2. Description of the Related Art
In recent years, CPUs (Central Processing Units) with a high frequency, and relatively high power consumption are becoming popular. Power devices of information processing apparatuses in which such CPUs are used are designed to meet the power supplying performance demanded in accordance with the increasing power consumption, and tend to be larger and more costly. In other words, a power device is designed taking the maximum amount of power consumption when all of the CPU, other chips, built-in drives, devices that may be connected to external device connector terminals, and the like are operating to their fullest capacity into consideration.
On the other hand, measures for decreasing power consumption by information apparatuses have been devised. Such measures include, for example, detecting when the apparatus is operating on batteries and altering the operation mode of the CPU to lengthen the operation time, or adjusting the backlight of an LCD (Liquid Crystal Display) to decrease power consumption. Another example is where the temperature of the CPU is detected, and when it exceeds a predetermined temperature, the operation mode of the CPU is altered, thereby preventing the CPU from being destroyed or from running out of control due to its own heat, and thus ultimately lowering power consumption (see, for example, patent document 1).
[Patent Document 1]
Japanese International Application Publication No. 2002-269272.

Information processing apparatus and method, as well as program


A ride-on turf mowing machine rollover protection assembly consisting of a mower chassis having left and right main rails and having a plurality of cross rails spanning between the left and right main rails; left and right upwardly opening quills; a first plurality of welds rigidly interconnecting the left main rail and the left upwardly opening quill; a second plurality of welds rigidly interconnecting the right main rail and the right upwardly opening quill; a roll bar having left and right legs, each leg having a lower end, the lower ends of the left and right legs being respectively closely fitted for nesting extension into the left and right upwardly opening quills; and a plurality of helically threaded bolt, nut, and double shear eye combinations removably mounting the lower ends of the left and right legs of the roll bar within the left and right upwardly opening quills.

Residential and commercial lawn tractors, garden tractors, front mower deck ride-on mowing machines, mid-mower deck ride-on mowing machines and zero turning radius (Z.T.R.) ride-on mowing machines (referred to below generally as ride-on turf mowing machines) are commonly shipped, stored, and operated in environments which varyingly give rise to desirability and a lack of desirability of mounting of an operator protecting roll bar. Where an operator of a ride-on-mower is secured upon the machine by a seat belt, and where the machine topples or rolls laterally, a roll bar installed thereon must extend upwardly overhead to an elevation sufficient to prevent an impact of the operator's head against the ground. Such ground contact may catastrophically fracture the operator's skull or neck. Accordingly, such roll bars typically extend approximately four feet above the operator's seat. Such upward roll bar extensions undesirably block compact stacked storage and shipping of ride-on turf mowing machines, giving rise to desirability of temporary removal of such roll bars during storage or shipping. Where a ride-on mower is operated exclusively upon substantially level ground surfaces, cost economies may be obtained by foregoing provision and mounting of such a roll bar, or by removing and interchanging such roll bar for use upon an alternate ride-on mower which is operated upon sloped ground surfaces.
Commonly, operator protecting roll bars are fixedly welded to frame members or chassis members of ride-on mowers. Directly welded attachments of roll bars advantageously provide structural rigidity and security against roll bar failure in the event of a rollover event. However, such welded attachments undesirably interfere with and prevent removal and interchangeability of roll bars for purposes of compact shipment and storage, or for achieving cost economies as described above.
The instant invention solves or ameliorates problems set forth above by providing a roll bar chassis mount assembly which efficiently, mechanically simply, and with cost economy alternately rigidly attaches a roll bar upon a ride-on turf mowing machine and permits detachment for roll bar removal.

Ride-on turf mowing machine rollover protection assembly


An elongated elastic cylindrical member joined at its opposite ends to form an annular member is provided. The annular member is designed for disposition about a body limb near the end thereof adjacent the torso and with the annular member circumferentially stretched and exerting a heavy radial inward pressure upon the limb at least substantially the full length of an elongated zone extending completely about the associated limb with the inward force of the annular member on the limb being sufficient to locally compress not only limb veins closely adjacent the skin surface but also arteries spaced further beneath the limb surface.. The method comprises hyperextending veins of the limb adjacent the free end thereof by gradually rolling the annular member downwardly along the limb toward the free end thereof with the heavy radial inward pressure upon the limb being sufficient to locally compress the veins and arteries of the limb beneath the annular member and to thereby "milk" both venous and arterial blood downwardly through the veins and the arteries of the limb, whereby at least one vein adjacent the end of the limb will be engorged with blood and sufficiently hyperextended for ease of location and insertion of a needle therein preparatory to intravenous therapy.

1. Field of the Invention
When desiring to initiate intravenous therapy, a person rendering the therapy must find a vein on a patient into which a needle may be introduced for use in carrying out the desired intravenous therapy.
It is now common practice to use a rubber tourniquet applied about an upper portion of a body limb for the purpose of restricting venous return of blood from that limb to the torso. When cardiac output is sufficient, the veins distal to the tourniquet become hyperextended as they fill with blood that is being pumped to their connecting arteries of the veins. The hyperstatic pressure created by the heart forces the blood through the arteries that lie underneath the tourniquet. Blood continues through the arterioles, capillaries, venules, and then the veins distal to the tourniquet. The constricting band action of the tourniquet limits or prevents the return of that blood to the heart. Then a hypertensive action becomes apparent as the veins distal to the tourniquet become engorged with blood and hyperextended. It is at this time that a needle may be introduced into a hyperextended vein for the purpose of intravenous therapy.
However, when a patient has substantially no cardiac output, a tourniquet is not operative to cause a vein to be hyperextended in order to facilitate the starting of intravenous therapy. When substantially no cardiac output is present the veins are substantially collapsed and only the arteries of a body limb disposed considerably below skin surface have any appreciable amount of blood therein. Accordingly, in many instances, paramedics, nurses and doctors attempting to introduce a needle into a vein are unable to find such a vein. Of course, time lost in starting intravenous therapy under these conditions often is a matter of life or death. A doctor may try several minutes in a critical situation and then, as a last resort, attempt to introduce the needle into a femoral artery or perform a "cut down" (minor surgical procedure) or may do a subclavian. All of these procedures are time consuming and the accumulative loss in time may be critical.
Accordingly, a need exists for a means by which a suitable vein may be engorged with blood and thus hyperextended, even when the patient has little or no cardiac output.
2. Description of the Related Art
While there have been many different forms of tourniquets heretofore utilized, none of the previously used forms of tourniquets are operative, on a patient with substantially no cardiac output, to engorge a vein with blood so as to present a hyperextended vein into which a needle may be readily introduced for intravenous therapy. Examples of previously known forms of tourniquets and similar structures are disclosed in U.S. Pat. Nos. 1,757,060, 2,091,131, 2,511,269, 3,467,077, 3,570,495, 3,586,001, 3,587,584, 3,654,931 and 4,066,084.
The massaging apparatus disclosed in U.S. Pat. No. 2,091,131 comprises a roller assembly adapted to be encircled about a body limb such as an arm and to be rolled up and down the arm as a massaging device, the massaging device incorporating relative soft and porous rollers so as to massage and knead the body of the patient in a gentle manner, which massaging action is not effective to carry out the objects of the instant invention and which gentle manner is likewise ineffective to carry the objects of the instant invention.
Still further, U.S. Pat. No. 4,066,084 to Tillander is designed specifically to gradually upwardly compress circumferential zones of a body limb in order to empty blood from the limb extremity toward the heart of a patient prior to surgical incision. Inasmuch as this apparatus is designed to empty the blood from a limb extremity toward the heart of a patient it accomplishes the exact opposite of the instant invention which is designed to engorge a vein toward the extremity of a limb by milking not only any small amount of venous blood toward the limb extremity but also milking deeper level arterial blood toward the extremity. Further, the Tillander apparatus substantially totally encloses the portion of the limb to which it is applied, thereby preventing any access to an underlying vein. Further, because of the shape of the Tillander apparatus it is not reversible on the extremity for operation in emptying blood from a limb toward the extremity thereof.

Method and apparatus for enabling intravenous therapy when cardiac output is less than usually necessary


Methods and apparatus for providing a durable, lightweight lifting member and assembly for use in handling elongated members. One embodiment comprises a cage or net made of a flexible material, the cage or net being adapted to receive one end of an elongated member. Another embodiment is characterized by a flexible lifting member constructed of a pliable, non-metallic material and comprising a body portion, an end portion, and a lifting strap.

The present invention relates generally to methods and apparatus for lifting. More specifically, the present invention relates to methods and apparatus for lifting elongated objects, such as tubing or pipe.
The invention can be used with any type of elongated member made from any material, including solid members such as rods. Additionally, despite being described at times below as related to the oilfield and drilling industry, the invention is not so limited and can be used in any industry.
The drilling and production of hydrocarbon wells involves the use of large quantities of tubing, including pipe as a component of a drillstring and casing used to line the well. Normally, this tubing is available in sections of twenty to forty feet in length. These individual sections are then connected together to form the drillstring or casing tubing. A standard hydrocarbon well drilled on land may employ thousands of feet of drill pipe and tubing, requiring thousands of individual joints of tubing and pipe to be handled while drilling the well. An deep water offshore well may require considerably more pipe or tubing.
The individual sections of tubing are normally transported from a fabrication facility to the well site by truck or supply boat. The tubing must then be moved from the truck or boat to the drilling rig in a safe and secure manner. Some tubulars, such as pipe, have threaded pin ends and box ends, which help prevent the pipe from being damaged during transport. Because of the large number of tubulars used in drilling a well, the handling of these tubulars is of great concern in the operation of a drilling rig.
One method utilized in handling tubulars has been simply to use a harness or sling to wrap around the tubular in a "choker" configuration and lift the tubular by the sling. Lifting from a single point lift, as described above, requires a great deal of effort in properly locating the lift point near the center of mass of the tubular so that the tubular remains balanced during the lift. This method is not favored because of the inherent risk to men and material should the tubular not be lifted in a balanced manner.
Another method involves using a lifting appliance having hooks that are designed to grasp into the ends of a tubular. The hooks are typically connected via wires to a centralized lifting point. These hooks are inserted into the open ends of a tubular and bear against its inside surface. This type of lifting hook has been known to cause damage to the tubular interior or threaded connections, particularly when the interior of the tubular is coated. If damaged, the tubular often has to be trimmed down to remove the damaged area.
Another method involves metal end caps placed over each end of the tubular. The caps are typically connected via wires to a centralized lifting point. These metal end caps commonly have an elongated body with a solid plate attached to one end. Attached to the body is a lifting lug that can then be coupled to a central lifting point. These metal end cap assemblies surround the entire end portion of the tubular and prevent the damage often caused by lifting hooks. One drawback of these metal end cap assemblies is their weight, especially for larger diameter pipe. The heavier the end cap, the more difficult to handle. Another drawback with such assemblies is they allow metal to metal contact with the pipe, which can damage the pipe. Metal lifting appliances are also subject to corrosion and maintenance problems, especially in offshore applications.
Additionally, a general problem in pipe lifting is the requirement by some drilling contractors that the thread protectors on the ends of the tubular be "non-liftable." This requirement stems from the fact that many present lifting devices, such as lifting hooks, damage the interior of the tubular. Accordingly, thread protector manufacturers needed to design and manufacture a protector that prevented such damage. This was accomplished by sealing the end of the protector, in some instances with a cover (such as a metal plate), so that lifting hooks could not be inserted into the interior of the pipe. This increases the costs of protectors and, more importantly, cannot guarantee that personnel handling the pipe will not break open through the cover and insert a lifting hook. Applicants' invention obviates the need for a "non-liftable" protector and ensures that the interior of the pipe is not damaged during the lifting process.
Thus, there remains a need in the art for methods and apparatus for safely and efficiently lifting tubulars, or other objects, in a manner that does not damage the tubular or object. Therefore, the embodiments of the invention are directed to methods and apparatus that seek to overcome these and other limitations of the prior art.

Drilltec Patents & Technologie Company, Inc.


A lockable valve (7) for a fuel line contains a fuel inlet (2) and fuel outlet (3) which communicates with one another via a passage (6) in which is located a spring-biased piston (15) which is responsive to a pressure change in the fuel line. Associated with the piston (15) is a spring biased plunger (11) which controls a valve (8) to close or restrict the flow of fuel through passage (6). At the other end of the piston (15) is a resetting device (23, 24) which requires an unlocking action before the piston can be extended to withdraw the plunger 11 so as to open the valve. When a fall in pressure is detected by the piston (15), it causes operation of the valve (8) to stop or restrict fuel flow but this operation may only be reversed by the unlocking action.

A number of devices exist by which engines can be immobilised to prevent theft or misuse of a vehicle or machinery etc. Many devices are mainly concerned with the locking or disconnection of electrical circuits associated with the engine which prevents the engine from being activated. It has been found that most or all the currently available methods which utilise the locking or disconnection of engine electrical circuits in vehicles can be over-ridden, by-passed or otherwise neutralised so allowing the theft or misuse of the vehicle.
Vehicles can also be immobilised with varying degrees of success using mechanical devices ranging from steering wheel and brake locks to lockable fuel valves.
French Patent Specification No. 2138170 (Emca Reg. Trust), German Patent Specification No. 640 533 (A. H. Adelsohn, J. F. Hultman), French Patent Specification No. 2647 877 (Alexanare Yanacopoulo), also disclose key actuated lockable fuel valves. Similarly, British Patent Specification Nos. 2 196 413 (Spouse), 130 344 (Emca Reg. Trust), 988 912 (Ross Courtney and Company Limited, 422 494 (Adelsohn), 190 832 (Hopkins) and U.S. Pat. No. 3,885,586 (Tibbets) and U.S. Pat. No. 3,838,587 (Good) all describe various types of fuel valves to prevent vehicle theft.


The present invention discloses to polyaniline derivatives which are soluble in an organic solvent and with which it is possible to produce a film having flexibility, and to a process for preparing the same. The present invention provides polyaniline derivatives comprising a structural unit which is indicated by the following formula (I) ##STR1## (wherein m is an integer of 0 or greater, and n is an integer of 2 or greater), and a structural unit which is indicated by the following formula (II) ##STR2## (wherein k is an integer from 1 to 2500, and x is a group with at least a 2-butenylene structure).

Field of The Invention
The present invention relates to polyaniline derivatives which can be dissolved in organic solvents and with which they are possible to produce a film having flexibility, and to a process for preparing the same.
In recent years, the application of polyaniline as a new electronic or conductive material in such varied fields as, for example, cell electrode materials, antistatic materials, electromagnetic shielding materials, functional devies--e.g., photoelectric transducers, optical memories and various sensors-, display devices, various hybrid materials, transparent electroconductors, and various terminal equipment.
However, generally, polyanilines have a highly developed .pi.-conjugated systems, and therefore the main chain of polyaniline is stiff, and the interactions between the chains of molecules are strong. Because of the many strong hydrogen bonds which exist between the molecule chains, there are many organic solvents in which polyaniline is insoluble, nor can the polyaniline, and cannot be melted by heating. Therefore, a serious defect arises from the inability of polyanilie to be processed to a film.
Therefore, composite materials were prepared by impregnating a monomer comprising aniline with a backing of a desired shape such as that of a porous material or a fiber made of a polymer. The monomer was then polymerized by contacting the monomer with polymerizing catalysts or by electrolytic oxidation, or by using a thermal plasticity polymer powder. In contrast, a polyaniline soluble only in N-methyl-2-pyrrolidone in synthesized by controlling the reaction temperature and selecting polymerizing catalysts (M. Abe et al.; J. Chem. Soc, Chem. Commun., 1989,1736). However, this polyaniline also is insoluble in other ordinary organic solvents, and therefore the range of application of the polyaniline was limited. In addition, although soluble polyaniline derivatives were synthesized from many kinds of aniline derivatives, the films made of such polyaniline derivatives did not exhibit sufficient flexibility.

Polyaniline derivative containing at least a 2-butenylene structure


A first request is received to access a first set of data in a first cache. A likelihood that a second request to a second cache for the first set of data will be canceled is determined. Access to the first set of data is completed based on the determining the likelihood that the second request to the second cache for the first set of data will be canceled.

The present disclosure relates to computing systems that employ one or more caches. More particularly, the present disclosure relates to completing data requests based on selective downstream cache processing.
Cache memories in a computing system can improve processor, application, and/or computing system performance by storing data (e.g., a computer instruction, or an operand of a computer instruction) in a memory that has a lower access latency (time to read or write data) as compared to other memories, such as a main memory (e.g., primary RAM) or a non-volatile storage device (e.g., a disk). Cache memory can be included in a processor, and/or between a processor and another memory (e.g., another cache memory and/or a main memory) and can store a copy of data otherwise stored in a main memory. For example, processors can include a local, or "Level 1" (L1), cache, and computing systems can include additional caches, such as "level 2" (L2) and "level 3" (L3) caches, between a processor (or, a local cache of a processor) and another memory (e.g., a main memory).

This patent is subject to a terminal disclaimer.

Selective downstream cache processing for data access

International Business Machines Corporation


In some embodiments, a method for high-performance terrain rendering may include one or more of the following steps: (a) obtaining elevation data, (b) determining slope of a terrain surface, (c) selecting a shading model to apply to the terrain surface based upon the slope of the terrain surface, (d) determining if a vehicle's heading has changed, and (e) aligning the shading model index based upon current heading.

Rendering is the process of generating an image from a model, by means of software programs or electronic hardware. The model is a description of three dimensional objects in a strictly defined language or data structure. The model may contain geometry, viewpoint, texture and shading information. The image, produced from rendering, is a digital image or raster graphics image. 'Rendering' is also used to describe the process of calculating effects in a video editing file to produce final video output.
Rendering is one of the major sub-topics of 3D computer graphics, and in practice always connected to the others. In the graphics pipeline, it is the last major step, giving the final appearance to models. With the increasing sophistication of computer graphics since the 1970's onward, it has become a more distinct subject.
In computer graphics, shading refers to the process of altering a color of a surface based on its angle to lights to create a photorealistic effect. Shading is performed during the rendering process.
Flat shading is a shading technique used in 3D (three dimensional) computer graphics. It shades each polygon of an object based on the angle between the polygon's surface normal and the direction of the light source, their respective colors, and the intensity of the light source. A surface normal, or just normal to a flat surface is a three-dimensional vector which is perpendicular to that surface. A normal to a non-flat surface at a point p on the surface is a vector which is perpendicular to the tangent plane to that surface at p. The word normal is also used as an adjective as well as a noun with this meaning: a line normal to a plane, the normal component of a force, the normal vector, etc.
Illumination shading of surfaces (such as terrain) is typically accomplished through a set of vector calculations repeated for each point in the surface. When an application demands a changing orientation of the light sources, the calculations must be repeated.
This requires considerable computation resources for avionics systems where the light source moves dynamically with mid-flight heading changes. This light movement is required for human factors depth-cueing reasons. Correct depth cueing is best maintained with the dominant light source positioned approximately 45 degrees to the left of current heading and some fixed angle above the horizon. High-performance terrain rendering applications require complex shading models consisting of multiple light sources varying in direction, intensity, and chromaticity. The increased computational complexity adds to the cost and complexity of the system. For terrain representations, calculation precision must be relatively high to avoid a noisy appearance in smooth regions.
Therefore, it would be desirable to provide a method and apparatus to reduce computational resources and cost for light shading in high-performance terrain rendering applications.

Dynamic light shading in terrain rendering applications


A liquid crystal display. The display has a substrate and a first counter electrode formed on the substrate. The first counter electrode extends in a first direction. An insulating layer having a contact opening is formed on the substrate, which has the first counter electrode. A pixel electrode is formed on the insulating layer and has a body separated from the first counter electrode by a selected distance. The pixel electrode also has a plurality of comb-teeth, which extends parallel to the first counter electrode from the body of the pixel electrode. The body extends in a second direction substantially perpendicular to the first direction. A second counter electrode is formed on the insulating layer. The second electrode also has a body extending parallel to the body of the pixel electrode. The pixel electrode has a plurality of comb-teeth extending from the body of the second counter electrode in the first direction. The body of the second counter electrode overlaps the first counter electrode at one end thereof. The plurality of comb-teeth of the second counter electrode interdigitate with the plurality of the pixel electrode by a predetermined distance.

The present invention is related to liquid crystal displays ("LCDs"). More particularly, the invention provides an LCD having a counter electrode that has a first part and a second part and a pixel electrode.
A liquid crystal display ("LCD") has elements such as a pair of transparent insulating substrates, a thin film transistor ("TFT"), and a pixel electrode. The thin film transistor and pixel electrode are formed on one of the transparent insulating substrates. A color filter and a counter electrode are formed on the other insulating substrate. A liquid crystal material is placed between the pair of substrates. In operation, an electric field is formed between the pixel electrode and the counter electrode by way of an applied voltage. Liquid crystal molecules rearrange along the electric field between the electrodes.
An in-plane switching ("IPS") mode thin film transistor had been used or suggested for improving limitations such as a low viewing angle and a low contrast ratio. The IPS mode TFT has a pixel electrode and a counter electrode which are formed on a lower substrate. Between the pixel electrode and the counter electrode is formed an electric field, so along the electric field the liquid crystal molecules are rearranged.
A variety of limitations exist with conventional LCD designs such as the one described above as well as others. In particular, the conventional LCD design generally has inefficient designs that tend to reduce transmittance of the LCD. Additionally, conventional LCD designs do not form the pixel electrode and the counter electrode on the same plane. Accordingly, LCD response times are often reduced. Furthermore, conventional LCD's often use opaque metal materials, which generally require more power to achieve a desired luminance. The conventional LCD may also output images that are distorted and the like by way of conventional design layouts.
From the above, it is seen that an improved liquid crystal display is desired.

Active matrix liquid crystal display having interdigitated pixel and first counter electrodes in the same plane and a second counter connected to the first counter electrode via a contact hole in a insulating layer

Hyundai Electronics Industries Co., Ltd.


A system for performing an ocular surgical procedure is provided. The system includes a multiple frequency signal source, a configurable tuned output filter connected to the multiple frequency signal source, and a multiple frequency ultrasonic handpiece. The multiple frequency signal source operates at a first frequency and is configured to drive the configurable filter and the multiple frequency ultrasonic handpiece at the first frequency. The multiple frequency signal source operates at a second frequency and is configured to drive the configurable filter and the multiple frequency ultrasonic handpiece at the second frequency, and the design addresses third harmonic frequency issues for the multiple frequency ultrasonic handpiece. Switchable passive components, such as inductors, resistors, and/or capacitors may be employed in the configurable tuned output circuit, or alternately multiple similar circuits may be employed. Alternately, a multi-tap transformer may be provided.

Field of the Invention
The present invention relates generally to the field of ocular surgery, and more specifically to a method and apparatus for controlling a phacoemulsification handpiece and needle configured for operation at multiple ultrasonic frequencies during ophthalmic surgical procedures.
Description of the Related Art
Phacoemulsification surgery has been successfully employed in the treatment of certain ocular problems, such as cataract surgery, including removal of a cataract-damaged lens and implantation of an intraocular lens. Phacoemulsification surgery typically involves removal of the cataract-damaged lens and may utilize a small incision at the edge of the cornea. Through the small incision, the surgeon then creates an opening in the capsule, i.e. membrane that encapsulates the lens.
The surgeon can insert an ultrasonic probe, incorporated within a phacoemulsification handpiece, through the opening in the cornea and capsule accessing the damaged lens. The handpiece's ultrasonically actuated tip emulsifies the damaged lens sufficient to be evacuated by the handpiece. After the damaged natural lens is completely removed, the handpiece tip is withdrawn from the eye. The surgeon may now implant an intraocular lens into the space made available in the capsule.
While performing phacoemulsification surgical techniques, such as lens removal, the surgeon may desire to employ either a longitudinal motion or a mix of longitudinal with transversal motions, also referred to in the industry as transverse phacoemulsification, to affect different desired cutting movements. Certain previously available ultrasonic probe designs provided for only one type of cutting movement such that if the surgeon determines during the procedure a need to switch from, for example, longitudinal to transverse cutting movements, the surgeon has been required to change the ultrasonic probe handpiece. This changing of the handpiece during surgery can complicate and lengthen the procedure.
It is desirable to provide the surgeon with a single handpiece capable of operating in either the longitudinal or transverse modes or some mix of them that provides an elliptical mode. The frequency of handpiece operation for longitudinal or transverse modes are determined by the physical and electrical properties of an ultransonic handpiece. The operational frequencies are on or about the resonant frequencies of the handpiece and these frequencies are generally different for longitudinal and transverse modes. The driver of such a handpiece must therefore operate at multiple frequencies.
Past handpiece drivers were linear class AB types or similar. Although these drivers exhibited a flat (acceptable) frequency response and were therefore capable of handling a multiple frequency handpiece, they were very inefficient in power delivery, required heatsinking, had a high quiescent current, suffered from crossover distortion, and were generally complex designs. Power dissipation in these drivers is high and the resulting heat can be destructive if not properly managed.
Modern handpiece drivers are class D designs. A class D driver is operated in an ON/OFF mode or Pulse Width Modulation mode instead of linear mode. This type of driver is very efficient and less complex than a class AB driver. Because of the digital (ON/OFF) nature of the driver, the input signal is digital in nature (pulse width modulation, pulse frequency modulation, etc) and the driver output is also digital in nature. When used to drive an ultrasonic handpiece on or about its resonant frequency, it is desirable to remove all but the fundamental frequency from the driver output so as to limit power dissipation in the handpiece at undesirable frequencies and to eliminate distortion in handpiece voltage and current feedback signals that are used to control handpiece operation. Consequently, a filter circuit is generally inserted between the driver output and the handpiece to remove unwanted harmonics and provide a sine wave drive signal to the handpiece.
Since the driver output is generally a step-up transformer to generate the high voltages required to drive the handpiece and because of filter power dissipation, the filter circuit is generally made of passive components (L, R, C). 2-Pole L-C filters are preferred for lower dissipation and fast roll off of gain with frequency but they suffer from gain peaking around the cutoff frequency.
Typical current designs employ a single fixed output filter for a needle operating at multiple frequencies, primarily to minimize costs and complexity. However, use of a single output filter design can result in undesirable third harmonic frequencies to the handpiece when the phacoemulsification handpiece operates at more than one frequency, particularly when switching between frequencies. Variations in gain experienced at different frequencies may limit the ability to deliver sufficient power at each frequency to adequately drive the handpiece needle.
Single output filters are limited to providing only one fixed relatively low cut-off frequency. An output filter designed to provide gain at the fundamental frequency and rejection of third and higher harmonics for a 38 kHz ultrasonic handpiece cannot maintain a comparable or consistent gain and third harmonic rejection for a 26 kHz ultrasonic handpiece using simple passive filtering.
If the low cut-off frequency for the output circuit is set at too high a level for use with a 38 kHz handpiece a relatively significant third harmonic energy will occur in the output signal resulting in a distorted waveform when driving a 26 kHz handpiece. When a waveform distorts in this manner it becomes difficult for system monitoring circuits to measure the correct voltage and current values used to excite the piezoelectric crystal and to control handpiece operation.
When configuring a single output filter circuit to provide a sufficiently low cut-off frequency for removing the third harmonic distortion from the output signal waveform, resulting from operating the circuit at the first lower frequency such as 26 kHz, the circuit's resultant gain at 38 kHz may be too high or too low depending on placement of the cutoff frequency and the Q of the L-C filter.
Based on the foregoing, it would be beneficial to offer a single output filtering mechanism design for operating an ultrasonic probe at multiple frequencies that overcomes the foregoing drawbacks present in previously known designs used in the ocular surgical environment.

Multiple frequency phacoemulsification needle driver


A contact of an LGA socket comprises a main plate having two guiding and positioning extensions projecting upward from two ends of a beveled upper edge thereof, two lower engagement pins extending downward from two ends of a lower edge of the main plate, and at least one barb formed on each of two opposite vertical sides of the main plate. A resilient C-shaped upper engagement pin curvedly extends upward from a middle portion of the lower edge of the main plate and includes a contacting tip extending upright from one end of the upper engagement pin substantially beyond a horizontal level of the two guiding and positioning extensions.

1. Field of The Invention
The present invention relates to a contact for an LGA socket, and especially to a contact having a simple and reliable structure for use in an LGA socket.
2. The Prior Art
Land grid array (LGA) sockets are commonly used with IC packages and do not require soldering procedures during engagement between the LGA socket and a related mother board. Normally, an LGA assembly includes an IC package having a plurality of flat contact pads formed on a bottom surface thereof, a socket having an insulative housing and defining a plurality of passageways therethrough, and a plurality of conductive contacts received in the passageways of the socket. Fastening means consisting of a top plate positioned on a top surface of the IC package, a bottom plate positioned on a bottom surface of the PCB, and a plurality of sets of aligned holes defined through the PCB, the top plate and the bottom plate is used to configure the assembly. Each set of aligned holes receives a screw therein which engages with a washer and a nut thereby sandwiching the LGA assembly between the top and bottom plates.
U.S. Pat. No. 5,653,598 discloses an electrical contact for use in a connector 30 between mutually opposed electrical interfaces 40, 8 such as contact pads respectively formed on an IC package 2 and a printed circuit board 6, as seen in FIG. 5. The conventional contact comprises a generally planar contact body 10 having first and second major faces 110, 120. The body includes a pair of spaced apart spring arms 140, 150 connected by a resilient bight portion 160. The spring arms 140, 150 each have a free end with an outwardly facing edge forming a contact nose 17, 18 for engaging with the corresponding interface 40, 8. Shorting sections 19, 20 generally extend toward each other from the free ends and are offset such that, upon deflection of the spring arms 140, 150 toward each other, the shorting sections 19, 20 overlap and the first major face 110 engages the second major face 120. Thus, a shortened electrical path is formed between the contact noses 17, 18 when the package 2 is urged against the connector 30.
However, the shorting sections 19, 20 may not properly contact each other due to unwanted lateral deflection thereof when the bight of the contact is deformed. Although the inner wall of the passageway receiving the contact may be used to limit the lateral deflection of the shorting sections 19, 20, unwanted scraping of the shorting sections 19, 20 against the inner wall of the passageway may occur thereby adversely affecting the proper overlap of the two shorting sections 19, 20. Proper overlap and engagement of the two shorting sections 19, 20 is difficult to achieve with this structure. Therefore, it is requisite to provide a new structure of the contact by which a shortened connection path may result upon urging the IC package against the connector.