A modular, wooden, pool cover frame, designed to replace conventional floating supports with a frame that spans the area above the pool, providing rigid support that is not susceptible to the problems such as puncture, rupture, structural integrity failure or water sitting on the pool cover. An A-frame like wooden structure covers the entire pool area. The frame is modular in design and has a plurality of locking wheel assemblies on the bottom thereof making it easy to store and set up, even by a single person. Depending upon the size and shape of the pool, a number of vertically aligned, equally spaced A-frame assemblies are placed spanning across the pool and are connected to one another by multiple support beams. Additional support arms are angled from the A-frame components to the ground in order to provide additional support. With the pool cover placed over the frame, a tent-like shape results that allows debris and water to run off the pool cover.

1. Field of the Invention
The present invention relates generally to pool covering devices, and, more particularly, to a modular, wooden, pool cover frame.
2. Description of the Related Art
Pool owners who live in areas that require that they leave the pools covered during the winter months know all too well of the burdens and hassles associated with pool cover maintenance. Typically, these covers are anchored around the pool perimeter and supported in the pool itself by balloon-like floats. The floating supports tend to either deflate or move about resulting in sagging portions that collect leaves, branches and water. As a result, the pool owner must constantly adjust the cover, reposition and inflate the floats, and tighten the perimeter anchoring. Furthermore, the cover can become damaged and torn due to the excessive stress created by the collected water and debris. Ultimately, the cover needs to be replaced prematurely and at a considerable cost. Accordingly, the need has developed for a pool covering method that solves the problems associated with conventional float-type support methods.
In the related art, several patents disclose improved support mechanisms for swimming pool covers including floatation devices, in-pool support devices and support frames that span the area above the pool.
U.S. Pat. No. 5,303,527, issued in the name of Perez et al., discloses a removable support apparatus for supporting a swimming pool cover. The apparatus consists of a plurality of elongated adjustable frame assemblies. Each adjustable frame assembly includes a pair of elongated frame members which are longitudinally displacable relative to each other to adjust the overall length of the frame assembly in order that the frame assembly can fit across the pool. The removable support apparatus includes an elongated hollow tubular post with a column member which is capable of telescopic movement. The column member's pivotal base pad sits on the bottom of the pool underlying one of the frame assemblies so as to support such frame assembly. The column member can be adjusted to a desired height. This device is limited to in-ground pools and requires installing at least one telescoping column member in an upright standing position on the floor of the pool to support the frame assembly. Furthermore, the capability for debris and water run off, if any, is minimum at most.
U.S. Pat. No. 4,429,425, issued in the name of Weir et al., discloses a locking retaining bead being fixed to and holding a swimming pool cover or dome. The retaining bead of the invention, which is secured to the peripheral edge of the cover, consists of an elongated hook-like cross section which can be horizontally inserted into a channel or groove. The retaining bead is preferably formed of a semi-rigid plastic. The channel or groove is provided with at least one vertical retaining lip in order to enhance the retaining power of the bead. Dislodgement of the bead, it being attached or secured to the pool cover, is prevented when such pool cover is elongated horizontally and the bead meets with the retaining lip and becomes wedged. Another retaining lip could serve to secure a pool liner in place when a retainer bead is installed in a channel or groove below aforementioned channel. This device is limited to in-ground pools and requires that the swimming pool coping be embedded in a poured concrete deck which surrounds the top of the pool, therefore posing a problem for existing concrete pools absent such embedded coping.
U.S. Pat. No. 4,092,809, issued in the name of Bellas et al., discloses domed roof structures consisting of a frame and covering to enclose or cover above and in-ground swimming pools, garages, greenhouses, patios, sheds, and the like. The domed roof structure consists of a domeplate occupying the top of the domed roof structure, the interlocking rafter-sections which connect to and extend from the domeplate to the base into which the rafters are locked, the ridge-plate and ridge-sections, and the cover, consisting of a lightweight durable material such as nylon, vinyl, etc. The domeplate, which covers a wide variety of shapes for enclosure such as circular, regular polygonal, and oval, interlocks with the upper ends of a plurality of rib sections. The rib sections extend in a downward arc to the base of the structure where their ends interlock with base or seat plates that border the area to be covered by the structure. A seat plate is held down by an U-shaped buckle for above ground swimming pools, whereas an eye-bolt is used with in-ground swimming pools. The eye-bolt is molded to the back of the seat plate and is secured by a rope, thereby providing a tight fit against windy conditions. This device discloses numerous shapes utilizing modified rib sections and dome plates. An A-frame dome plate is an example. However, to ensure the structure is interlocking, it utilizes tenons and spring loaded bolts instead of screws and nails in conjunction with standard mending plates, angle plates, and T-strap plates. Furthermore, this device utilizes an U-shaped buckle or an eye-bolt to immobilize the roof structure rather than casters with brakes.
U.S. Pat. No. 4,000,527, issued in the name of Gannon, discloses a swimming pool cover support frame consisting of a plurality of individual elongated floating tubular bladders. Inflation of such floating bladders accomplished preferably with the valve of the type permitting mouth inflation. The tubular bladder, when inflated, provides a tapered shape of decreasing diameter from the center of the framework toward the edge of the pool. The plurality of individual tubular bladders are tied together by way of a string or other appropriate fastening means laced through eyelets that are provided at the end of each individual tubular bladder, such as to form the floating frame. The floating frame is attached to the edge of the pool via passing a string through the eyelet of each individual bladder to a ring at the edge of the pool. The pool cover is then placed on top of the floating frame and properly attached to the edge of the pool, thereby yielding an appropriate slope from the center of the cover allowing rain and debris to run off. Because the device consists of inflatable tubes, it is subject to puncture, structural integrity failure, or deflation and therefore provides a limited margin of safety, durability, and overall effectiveness for rain and debris runoff.
U.S. Pat. No. 3,855,643, issued in the name of Sanford, discloses a swimming pool cover arrangement consisting of a skeleton frame mounted over a swimming pool and a flexible sheet material such as plastic to cover the frame. The frame comprises a longitudinally extending member or ridge pole and a plurality of rafters which laterally extend at the sides of the ridge pole. The rafters, consisting of pin anchoring devices with holes through which bolts are extended into, are attached to flanged fittings anchored in the deck which give the frame longitudinal stability. The framework is made up of galvanized steel tubing or pipes. A portion of the cover is not secured to the pool deck so as to allow easy access to and from the pool. Furthermore, by opening the end of the cover, any desired temperature may be provided on the inside yielding environmental control. This apparatus is for in-ground swimming pools only. In addition, the apparatus is unnecessarily complicated in the sense that its removal requires unhooking fittings, elastic cords, and anchoring devices, and removing bolts from pins, as compared to the present invention which utilizes wheels making it easy to move, store, and setup.
U.S. Pat. No. 3,534,412, issued in the name of Crook, discloses a cover support structure consisting of a center support member fabricated from lengths of thin wall metal pipe such as iron, steel, or aluminum, but a preferred material is plastic pipe, namely one made from polyvinyl chloride plastic compound. These center support pipe sections are joined by means of a four-way coupling and are supported by a plurality of individual side support pipe sections. The couplings are removably attached by pins inserted in openings provided on the four-way coupling. The support structure is adaptable for in-ground pools providing a coping or which have a substantially right angle merger of the sidewall with the pool walk. When the pool is provided with a coping, the side support pipe sections are removably attached to the pool by means of an anchor assembly. This anchor assembly includes a center upturned finger and two down turned fingers which grip the coping on the pool. The side support sections are inserted over the upturned fingers. When the sidewall of the pool and the walk area are joined at the upper end of the sidewall, the anchor assembly is constructed from round metal stock providing diverging fingers with straight down turned ends. Such ends should make about a ninety-degree angle with the straight portion of the fingers in order to conform to the shape of the pool's upper edge. Each down turned end provides a boot made of rubber or other plastic type of material bonded to the ends of the fingers. Such a boot prevents the down turned fingers from slipping on the sidewall of the pool. Two other embodiments for the anchor assembly may be utilized in the present invention. The first consists of bending a rod into a U-shape whereby the base portion of the U rests on the walk and the down turned ends rest against the sidewall of the pool. An upwardly projecting arm receives the lower end of a side support pipe section. The second embodiment consists of bending a rod into a V-shape with a base portion and two down turned ends. This embodiment utilizes a pivoting arm supported by a bolt being welded to the base portion of the V. The side support pipe sections are slipped there over. The cover support structure is covered by a flexible pool cover constructed from a suitable water and weatherproof material such as treated canvas. The pool cover, being larger than the support structure, is spread over such structure and extends out over the walk area. The pool cover is held in place by means of weighted bags. However, if desired, the edges of the pool cover may be provided with eyes and the pool cover can be tied to ground anchors. Alternatively, the pool cover can be anchored into recessed eye rings provided in the walk area.
This device is limited to in-ground pools and requires an anchor assembly utilizing either the coping of a pool, diverging fingers, or a pivoting arm, as compared to the present invention which utilizes casters with brakes as its anchoring means.
U.S. Pat. No. 5,426,899, issued in the name of Jones, discloses a swimming pool cover for enclosing a pool or similar rectangular space. The frame assembly of the pool cover consists of a plurality of opposed side and end support brackets arranged in pairs which are mounted along the periphery of the pool. Such support brackets are generally formed from a resilient metal such as aluminum. The support brackets on the first side of the enclosure are of uniform height, and the support brackets on the second or opposite side of the enclosure have a uniform height greater than the height of the brackets on said first side. Each leg member of each side support bracket assembly and end bracket assembly may be constructed with a telescoping section. This type of construction would allow each of the leg members to be telescoped upwardly or downwardly, hence allowing the cover to be elevated as desired. Support cables extend across the pool being supported by the support brackets. A plurality of elongated T-shaped track members are mounted on and supported by the support cables. The track members are generally formed from an extruded plastic material and are configured to receive and hold cover panels. The cover panels are generally formed of a durable flexible weather tight plastic such as polycarbonate sheeting. The cover panel consists of top, end, and corner cover panels. The top and end cover panels are substantially rectangularly-shaped sheets while each corner cover panel is a substantially triangularly-shaped sheet. The cover panel assembly is connected in series by the track assembly in order to cover the top, sides, and ends of the pool. The swimming pool cover is anchored by bolting or spiking each base member of the side-support bracket assemblies and end bracket assemblies to the foundation or into the soil surrounding the pool. If there is no foundation or if the pool cover is to be used as a tent or shelter, a strap is placed across each base member and elongated spikes are inserted through openings in the straps on both sides of the base members to secure such base members in position. This device utilizes cover panels held by T-shaped track members to cover its frame assembly and such frame assembly, being constructed generally of aluminum, is constructed so as to have a downward slope from one side to the other. This is unlike the present invention which has an A-frame like structure consisting of wood.
U.S. Pat. No. 4,683,686, issued in the name of Ozdemir, discloses a removable enclosure cover for a swimming pool area. The enclosure includes a plurality of flexible frame members of rectangular, opaque, transparent, and flexible panel sections with a flexible material such as canvas extending between such frame members. A pair of spaced parallel channel-shaped track members are embedded in the concrete walkway surface and extend along such surface down the sides of the pool. A guide means with at least one pair of rollers extends into the interior of the track members. One roller rolls along the bottom of the track members and is mounted on a vertically movable carriage which allows the frame members to be guided along the track members toward and away from one another to cover and uncover the area between the track members. A locking means is provided which includes a selectively movable clamping member that engages the associated track member in order to prevent movement between the guide means and track members. This device requires that track members be either embedded in the concrete walkway surface or in the case of existing pool structures, to be mounted on the top surface of the pool deck, as compared to the present invention which utilizes casters with brakes as its anchoring means.
U.S. Pat. No. 4,051,638, issued in the name of Heintz, discloses an enclosure for a swimming pool or the like consisting of a cover and a frame. The frame includes a plurality of longitudinally spaced laterally extending ribs which arch over the area to be enclosed. Said ribs consist of a plurality of straight elements that are connected end to end by angularly shaped tubular sections and have their ends received and secured in the ground in vertical sockets. The tubular sections are secured by fasteners. The frame of this enclosure may be enlarged or reduced in size as desired by simply adding or subtracting ribs. The cover, preferably of a flexible plastic material, extends over the top of the frame. A pair of gripper boards or strips having tongue and groove formations are utilized to anchor the cover at the perimeter of the enclosure. This device utilizes some other material rather than wood for the construction of its frame; furthermore, the device utilizes ground sockets as its anchoring means unlike the present invention which utilizes casters with brakes as its anchoring means.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention. Consequently, a need has been felt for providing an apparatus and method which overcomes the problems cited above.

Portable, modular, wooden, pool cover frame


Apparatus for detecting degradation of the lubrication conditions of smooth bearings connecting a crank shaft to a connecting rod or connecting the crank shaft to the body of a machine that reciprocates in operation, lubrication being provided by oil circulation, the apparatus including means for detecting the phenomenon of seizure, wherein the apparatus comprises an additional bearing serving as a test bearing, said test bearing being lubricated by circulation of the same oil as is used for the other bearings and supporting a radially-loaded rotating shaft, said detection means being fitted to the test bearing which also includes means enabling it to be more sensitive than the other bearings to degraded lubrication conditions.

The smooth bearings of an internal combustion engine are lubricated by oil under conditions of pressure, of temperature, of grain size of possible impurities, and of water content on admission to the engine that are all monitored in operation.
Untimely deterioration in one or more of these parameters can cause the film of oil that normally separates the bearing from its bush to disappear. The resulting metal-on-metal contact at the conditions of relative speed and of unit pressure existing in the engine then gives rise to the metal of the bearing and of the bush becoming welded together locally and this gives rise to permanent damage of the bearing called "seizing" after some variable length of time that depends on the extent to which the oil film is reduced.
Various apparatuses are already known for warning the driver of the engine that seizing phenomena are beginning. The bush or its immediate environment may be fitted with a temperature sensor, but this can be difficult for a big-end bearing. A sudden and rapid rise in the temperature of the bush represents abnormal heating of the parts in frictional contact, and a priori the cause of such a temperature rise will be seizing.
The drawback of such apparatuses for monitoring the bearings in an internal combustion engine lies in the fact that they are not preventative since seizing must have begun before it can be detected. They are intended merely for reducing the amount of damage that occurs by enabling the driver of the engine to respond quickly.
According to the present invention, proposals are made to remedy this problem by means of a device that provides genuinely preventative detection of seizure conditions in the bearings of a reciprocating machine, and in particular the bearings of an internal combustion engine.

Apparatus for detecting bearing-seizing conditions in a reciprocating machine


A linear peristaltic pump of the type for removable engagement of a portion of a flexible tubing and having a plurality of sequentially actuated pumping elements which act along the engaged portion of the flexible tubing, with the pumping elements reciprocated in a first direction to collapse adjacent segments of the tubing and then in a second direction to release the adjacent segments of the tubing, each pumping element reciprocated in a sequence so that fluid in the flexible tubing is moved along the engaged portion of the tubing. The linear peristaltic pump further comprises a plurality of opposed pairs of pivotable reshaping fingers, with each pair of the reshaping fingers interposed adjacent to one of the pumping elements in sequence along the engaged portion of the flexible tubing. A finger drive and follower mechanism is formed by and engaged between each of the plurality of pairs of reshaping fingers and the adjacent ones of the pumping elements for actuating the reshaping fingers into reshaping engagement with the flexible tubing upon release thereof by the adjacent one of the pumping elements.

Traditionally intravenous infusion has been accomplished using gravity flow systems or drip regulated systems. Modern advances for regulating intravenous infusion have included various types of volumetric pumping systems. In situations where a patient is already established with a gravity-fed or drip-type IV, it often becomes helpful to convert the same system into one with a pump-controlled volumetric flow. For example, an emergency IV can be established in the field by paramedics, and upon arrival at a hospital, a doctor may need to administer medication at a precisely controlled flow rate. The same IV tubing system can then be conveniently adapted for controlled volumetric flow pumping through the use of various types of peristaltic pumps which engage the exterior of the established IV tubing. The typical IV tubing is made of a medical grade polyvinyl chloride (PVC) which has thin walls and is both flexible and resilient. Other more expensive tubing has been proposed to reduce collapsing, but at a cost of about ten times as much as PVC tubing. Alternatively, a combination of types of tubing has been proposed, such as silicon tubing spliced along a length which will be subjected to peristaltic pumping action. Such combination systems can also have a cost significantly greater than PVC (about five to eight times as much), because of the materials, splicing and additional sterilization required. Pumps which act upon the outside of the tubing walls to pump fluid within the tubing at a controlled rate permit the medical practitioners to avoid disturbing existing catheters or needles already established into the patient.
Thus, various types of modern pumps have been used for pumping fluid through an IV tubing, including pumps with a rotating arm, with rollers affixed at both ends of the arm. The rollers are positioned adjacent a curved IV holding channel to engage and roll along a section of tubing placed into the holding channel, thereby advancing a column of liquid therethrough. As the arm rotates, the rollers alternately engage the tubing, one behind the other, and successive columns of liquid are moved through the tubing. Rotation of the arm continues and repeats the pumping action.
Another type of pump is one which is referred to as a single-plunger peristaltic pump. This type of pump has an entry valve which compresses the tubing shut at an upstream point. A single elongated plunger then squeezes a predetermined length of the tubing along a linear section ahead of the closed entry valve. An outlet valve then compresses the tubing downstream from the elongated plunger after the liquid in the linear section is squeezed out and moved toward the patient. With the outlet valve closed, the entry valve is opened and the elongated plunger is retracted to allow fluid to move back into the linear section between the entry valve and the outlet valve. The entry valve is then closed, and the outlet valve is opened so that compression of the single elongated plunger can pump more fluid through the tubing.
Another type of pump, which is referred to here as a linear peristaltic pump, uses a series of pumping elements which each engage and sequentially compress a plurality of small segments along an engaged portion of the IV tubing. Each pumping element in sequence at its maximum stroke acts as a seal valve to prevent unwanted reverse flow. Separate inlet and outlet valves are not required in such a linear peristaltic pump. The sequence repeats, and the pumping element reciprocating strokes are typically timed to repeat the milking cycle without interruption. The rate of flow is controlled by changing the rate of reciprocation while the magnitude of the stroke is constant.
With each of the various types of peristaltic pumps described above, the IV tubing is repeatedly collapsed to force the fluid out of the tubing in one direction and then released to allow fluid to reenter from the other direction. After a period of use, the PVC tubing material becomes progressively flattened and permanently deformed such that the walls become creased and the interior volume of the tubing changes over the normal time period of operation. Tubing subject to permanent deformation reduces the pumping efficiency and reduces the accuracy of the pump. To the extent that attempts at reshaping may cause additional crease lines, the risk of premature cracking, tearing or rupture may also be increased, particularly at crease lines. Thus, the tubing must be changed frequently and must be carefully monitored to avoid lost efficiency, inadequate flow, inaccurate and improper volumetric flow or other failure of the system.

Linear peristaltic pump with reshaping fingers intedigitated with pumping elements


A digital phase locked loop with fast locking capability includes a digitally controlled oscillator for producing an output signal phase locked to an input reference clock, a phase detector for measuring the phase difference between said input reference clock and a feedback clock, and a loop filter for producing a control signal for the digitally controlled oscillator The loop filter includes a proportional circuit for developing a first signal proportional to said phase difference, an integrator for developing a second integrated signal from said first signal, an adder for adding said first and second signals to develop said control signal, and a weighting circuit, preferably a linear multiplier, for selectively adding extra weight to the first signal at an input to the integrator to shorten the locking time of the phase locked loop in a fast locking mode and to rapidly achieve a stable frequency in holdover mode.

In digital communications, where signal synchronization devices are used, there are often requirements for DPLLs that can meet certain standards which define their filter response, and also have the capability of fast locking to a reference signal. Fast locking is especially desired upon power-up and during manual clock reference rearrangement. The normal locking time for a DPLL is inversely proportional to its filter response, so fast locking is very useful when standards prescribe a slow response (small corner frequency).
In prior art DPLL implementations (e.g. the embedded DPLL in Zarlink's MT90866 H.110 Compatible Digital Switch), some instances of fast-locking have been achieved by pushing the DPLL corner frequency to the higher frequency range in the fast-locking mode. Quick response of the DPLL output clock to frequency changes of the active input reference clock could be achieved, as well as close alignment of the output clock edge to the active input reference clock edge. Locking time was very small for fairly large DPLL corner frequencies (i.e. greater than 1 kHz).
However, previous implementations fail to meet two major fast-locking mode requirements. Firstly, the holdover frequency could be far from the guaranteed holdover stability if holdover mode was entered shortly after the fast-locking time passes. In the holdover mode, the DPLL produces a stable output at the last locked frequency. Other techniques had to be used to prevent DPLL from entering holdover mode until the expiry of the normal DPLL locking time, which is defined by its filter response. Secondly, the final output clock was not aligned to the active input reference after this short, fast-locking time. The phase difference from the active input reference clock to the output clock was proportional to the sampling error of the active input reference clock by the internal clock used in DPLL. This misalignment could cause failures in a system where that DPLL was used as clock synchronizer, especially in systems with high clock and data rate, comparable to the sampling error.

Digital phase locked loop with selectable normal or fast-locking capability


A dual-headed ratchet basin wrench for use with compression fittings having a lock nut affixed to a coupling wherein a pair of ratchet jaws rotate to turn the lock nut while a pair of stationary jaws serve to retain the coupling in position thereby overcoming the shortcomings of prior basin wrenches which would turn not only the desired lock nut but also inadvertently turn the coupling and loosen the connection on the other side thereby requiring the user to utilize a second tool to prevent the subjacent nut from turning.

1. Field of the Invention
The present invention relates generally to plumbing and, more specifically, to a dual-headed basin wrench that maintains the nut of a main water supply in a stationary position while turning the nut of a supply line leading to a faucet.
Space is very limited under sinks due to an enclosed area having a plurality of supply lines, a drain assembly and other such obstacles thus making simple chores like disconnecting a supply line difficult with wrenches that are turned perpendicular to the fitting. Removing an old faucet and installing a new one is next to impossible with out a basin wrench (also referred to as a faucet wrench). In order to remove/install a faucet on a working sink it's necessary to loosen/tighten locknuts that are located underneath and behind the sink bowl. Not only is it necessary to twist your body into a small space, you are laying on your back and there's only about three inches of working space around these locking nuts. A basin wrench is a plumbing tool for removing and installing sink faucets and is often used in such instances. A basin wrench has a long handle that reaches up from under a sink to turn nuts on fittings and faucets. A basin wrench is normally used to loosen or tighten locknuts for supply hoses attached to compression fittings. Unfortunately, the pressure applied to the locknut often loosens the connection of the coupling on the main water supply side which often requires the use of a second tool to maintain the coupling in a fixed position as the locknut is being turned. This is quite undesirable considering the already cramped worked space and awkward positioning. The present invention seeks to overcome the shortcomings of the prior art by introducing a dual-headed basin wrench that will have a ratcheting head that will turn the locknut and a stationary head that will secure the coupling in a fixed position when pressure is applied to the connected locknut being turned.
2. Description of the Prior Art
There are other remote wrench devices designed for plumbing systems. Typical of these is U.S. Pat. No. 41,485,062 issued to Baldus on Feb. 26, 1924.
Another patent was issued to Miller on Jan. 24, 1927 as U.S. Pat. No. 1,708,147. Yet another U.S. Pat. No. 1,914,827 was issued to Hammerich on May 1, 1931 and still yet another was issued on Apr. 2, 1957 Fish as U.S. Pat. No. 2,787,180 and still yet another was issued on Oct. 20, 1959 to Thompson et al. as U.S. Pat. No. 2,909,089.
Another patent was issued to Duncan on Jun. 17, 1975 as U.S. Pat. No. 3,889,558. Yet another U.S. Pat. No. 4,622,869 was issued to Lee on Nov. 18 1986. Another was issued to Singleton on Jul. 21, 1987 as U.S. Pat. No. 4,680,994 and still yet another was issued on Mar. 13, 1990 to Singleton as U.S. Pat. No. 4,907,476.
A patent was issued to Tavianini on Jul. 7, 1998 as U.S. Pat. No. 5,775,183. McCormick et al. were issued U.S. Pat. No. 6,330,840 on Dec. 18, 2001.
While these ratchet devices may be suitable for the purposes for which they were designed, they would not be as suitable for the purposes of the present invention, as hereinafter described.


A method and apparatus for fault detection of series diodes in rectifiers is disclosed, wherein the voltages across one or both of the individual diodes, and/or the voltage across the pair of diodes are measured to determine a ratio between two of those voltages. The ratio is then analyzed to determine if a fault (e.g., a short circuit or an open circuit) is present. In some embodiments, circuitry can be included to compensate for the normal variations in diode characteristics (e.g., reverse leakage current, reverse recovery charge) between the pair of series diodes to minimize the potential for erroneous fault detection.

The subject matter disclosed herein relates to fault detection of series diodes, and more particularly, a method and apparatus for fault detection of series diodes in rectifiers.
Rectifiers are used in a variety of applications to convert alternating current (AC) to direct current (DC), including synchronous electric machines, such as AC motors and generators, which typically have rotating field windings that need to be excited with large direct current (DC) currents in order to operate. To avoid the need to pass these high currents through carbon brushes and slip rings, many of these machines have brushless exciters. These brushless exciters include a rotating set of windings on the machine's rotor that pass through magnetic flux from stationary poles, producing AC current on the rotor. The AC current is then rectified to DC current using a set of rotor-mounted solid state diode rectifiers. Typically, three-phase rotor windings require six rectifier sets to achieve full-wave rectification. For added reliability, each rectifier set is often comprised of two redundant diodes, connected in series, where each diode has the capability to block the full operating reverse voltage by itself when reverse biased.
When series diodes in rectifier sets are functioning properly and reverse biased in the reverse polarity portion of the AC cycle, the pair of diodes will block the flow of current through the diode (while allowing only relatively small amounts of reverse leakage current (mA)) and be subjected to the full reverse voltage across the pair of diodes. A common failure (or fault) of a diode is when the diode allows current that is higher than the normal reverse leakage current to flow when reverse biased. This type of fault can result from a reverse breakdown failure where the reverse voltage damages the diode in some cases to the point where the diode operates as a short circuit when reverse biased. The reverse breakdown failure frequently occurs during transient conditions where the peak reverse voltage exceeds the maximum allowable reverse voltage rating of the diode, which causes a fusion or other breakdown of the diode's PN junction. After a reverse breakdown failure, a diode can no longer effectively block current in the reverse polarity portion of the AC cycle, causing the rectifier current to reach relatively high values and low reverse voltages. Other types of faults (e.g., pinhole shorts) can result in the diode allowing current that is higher than the normal reverse leakage current to flow when reverse biased without necessarily forming a short circuit. As used herein, the term short circuit shall be understood to be a fault condition in a reverse biased diode where the current flowing through the diode is higher than the normal reverse leakage current expected in a properly functioning diode. If only one of the pair of series diodes experiences a short circuit, the other diode can be rated to withstand the full reverse voltage on its own (e.g., 300V to 1000V) and continue to perform the required rectifier function. One problem with the use of redundant diodes is that, if there is no indication that one of the pair of redundant series diodes has experienced a short circuit, the system will continue to operate with the vulnerability that the second diode may fail, increasing the risk of significant damage to the machine. It is, therefore, desirable to have a means of detecting a short circuit in a single diode so repairs can be made on a planned basis and a forced shutdown of the machine upon total failure of diode set can be avoided.
When series diodes in rectifier sets are functioning properly and forward biased in the forward polarity portion of the AC cycle, the pair of diodes will allow flow of current through the diode with a relatively consistent forward voltage (e.g., 0.7V at low current and up to 1.5V at rated current) across the diode. Although less common than a short circuit, another possible fault experienced by a diode is that the diode does not allow the flow of current in the forward direction, causing it to function as an open circuit when forward biased. Even if only one of the pair of series diodes experiences an open circuit, this would inhibit proper operation of that rectifier set, placing greater current demand on the remaining five rectifier sets. It is, therefore, desirable to have a means of detecting the open circuit failure of a single diode so repairs can be made as soon as possible.
Since the series diodes for brushless exciters are mounted on rotating components, the detection of diode faults requires a means of evaluating the condition of the rotating series diodes and then communicating that condition off the rotor. Rotor telemetry is a known technique for communicating electrical signals off rotors by transmitting signals modulated with either analog or digital data from rotor mounted electronic transmitter modules to nearby receivers using, e.g., radio frequency (RF) or optical transmission schemes. These rotor telemetry systems generally also include an inductive power feature that involves coils or antennas, one rotating and one stationary. These coils transmit electrical RF energy from a stationary source to the rotating component, and that energy is rectified to power the rotating transmitter. Typically, the same antenna coil structures that are used for induction power also convey the information signal off the rotor.
One approach to using rotor telemetry to detect diode failures for series diodes on brushless exciters is disclosed in U.S. Pat. No. 6,693,778 B1 to Pittman et al. The diode fault detection system measures the forward voltage across each of the pair of series diodes during the forward polarity of the AC cycle to detect a short circuit. The system compares the measured forward voltage of the diodes to a programmable alarm limit and triggers an alarm that indicates a failed diode or failed pair of diodes. The diode fault detection system is configured to detect short circuit faults only and not necessarily open circuit faults. In addition, measurement of the forward voltage to detect a short circuit can be unreliable since the diode can be damaged by peak reverse voltage in a manner where the forward biased characteristics of the diode are not significantly altered despite the fact that the diode can no longer block current when reverse biased. For example, the forward voltage of a diode with a pinhole short may be almost the same as the forward voltage of a properly functioning diode. Furthermore, since half of the diode fault detection systems are connected to the positive excitation terminal and the other half are connected to the negative excitation terminal, where the terminals have voltage potentials generally hundreds of volts apart, the forward voltage measurement requires two separate modules (one for the diodes on the positive excitation terminal and one for the diodes on the negative excitation terminal), which each need to be powered with an isolated power supply derived from a separate induction power coil.
Another approach to using rotor telemetry to detect diode failures for series diodes on brushless exciters is disclosed in U.S. Patent Application Publication No. 2010/0134075 A1 to Hlavac. The diode fault detection system connects a current source as a sensor across each of the pair of diodes to detect reverse voltage across the each of the diodes. If the sensor detects a reverse voltage across the diode, it is assumed that the diode is functioning, while if the sensor does not detect a reverse voltage across the diode, it is assumed that the diode is not functioning properly. The diode fault detection system is configured to detect short circuit faults only and not necessarily open circuit faults. In addition, making a decision on the presence of a reverse breakdown fault based upon the presence of reverse voltage in excess of a fixed threshold can be unreliable. Since the exciter may be operated over a large range of output voltages and diode characteristics within a rectifier set may be mismatched, a fixed threshold that is set too high may result in failure detection at low operating voltages when none exists and a fixed threshold that is set too low may fail to detect a real existing fault at higher operating voltages.
There is a need to provide improved detection of a diode fault (e.g., a short circuit or open circuit) in redundant series diodes in rectifier sets, including rectifier sets used for synchronous electric machines, such as AC motors and generators.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.

Method and apparatus for fault detection of series diodes in rectifiers


A system bus architecture for intermodular communications is disclosed. The system bus architecture comprises a backplane bus with associated memory and a plurality of control registers. A master system processor module is coupled to the backplane bus via a master bus controller. The master system processor module contains a central processing unit in selective communication the master bus controller. A plurality of slave modules are also coupled to the backplane bus via respective slave bus controllers. Each of the slave modules has a slave central processing unit in selective communication the slave bus controller. The master and slave bus controllers are in selective communication with the bus memory, the plurality of control registers, and the respective central processing units, to transmit and receive data through the backplane bus.

1. Field of the Invention
The present invention generally relates to system bus controllers and, more particularly, to a method and apparatus for intercommunication between system processor units (SPU), and between a SPU and all other system modules, including interface, clock, and switch units.
2. Description of the Prior Art
A system bus enables the exchange of data, usually in word-size quantities, among the various computer system units. In practice, a large number of units are connected to a single bus, with each unit contending in an orderly way for use of the bus for individual transfers.
The timing and sequence of data exchange between system components is controlled by a particular network bus architecture. One such architecture is known as Ethernet. All stations in a Ethernet are connected, through network interface cards or connectors, to a cable that is run to each user's equipment. The cable may be a unshielded twisted pair (UTP) wire (using an RJ-45 connector) or coaxial cable.
The Ethernet network uses a protocol called carrier-sense multiple access with collision detection (CSMA/CD). In the CSMA/CD protocol, each station shares the cable by constantly monitoring the cable to detect when it is idle (no user transmitting), when one user is transmitting (successfully), or when more than one user is simultaneously trying to transmit (collision).
The cable basically acts as a broadcast bus. Any station may transmit on the cable if the station detects it to be idle. Once a station transmits, other stations will not interrupt the transmission. With collision detection, if two stations begin to transmit at the same time, they detect the collision, stop, and retry after a randomly chosen period of time.
Ethernet networks have rated transmission data speeds of 10 million bits per second (Mbps). Idle time and collisions, however, can reduce the useful information throughput considerably, to approximately 1-2 Mbps. Fiber optic cables can not be used in such networks because they are not suited for direct taps by stations, which is possible with electrical coaxial cable.
In token ring networks, stations are arranged in an circle with point-to-point links between neighbors. Transmission flow is in one direction, either clockwise or counterclockwise. A transmitted message is relayed over the point-to-point links to the receiving station and then forwarded around the rest of the ring and back to the sender to serve as an acknowledgement. Only a station possessing a "token" (a single digital code word) may transmit. After transmitting, the station passes the token to its downstream neighbor, thus there are no collisions in a token ring.
Because token rings use point-to-point links, various transmission media such as shielded twisted pair (STP) and fiber optic cable may be used.
The transmission speed of a token ring depends on the transmission media used, ranging from 1 Mbps with STP to 16 Mbps with fiber optic cable. Most installations use STP, as it is the cheaper of the two.
These existing bus topologies have several disadvantages. For one, the transmission speeds are slow. As discussed above, while Ethernet speeds are rated at 10 Mbps, in actual operation they are much slower due to idle time and collisions. Token ring speeds range from 1-16 Mbps, but the data flow is unidirectional.
A second disadvantage is that large number of connecting pins are required and mechanical connections are required for the above topologies. Both topologies also require complex protocols to set up the messages and manage the data transfer. Finally, complex hardware schemes are required to support data transfer and error checking functions.
In light of the foregoing, there exists a need for system bus controller capable of wide bandwidth bi-directional data transfer, both between and among system processors and system modules, while employing simple protocols and hardware to format and manage data transfer.

Apparatus and method for intermodular communications using system bus controllers


Upon receiving a first e-mail, which is deprived of its attachment file due to a capacity limitation of mail server 21a, MFP 11a transmits a second e-mail containing its own IP address and a transfer request for transferring the attachment file to MFP 14a, which is the transmission source of the first e-mail, and other transmission destinations, MFP 12a and 13a. Of those MFPs which received the second e-mail, MFP 12a is accessible to MFP 11a via network 30 and transmits the attachment file to MFP 11a, and MFP 11a prints out the attachment file upon receiving it, according to an example configuration. The invention makes it possible to acquire and print out a file attached to an e-mail when it cannot be received directly due to the capacity limit of the mail server by obtaining it from the transmission source or from another transmission destination.

1. Field of the Invention
The present invention relates to an image processing device. More specifically, it is an image processing device being capable of printing a file attached to an electronic message when it cannot be received due to the capacity limit of the mail server by acquiring it from the transmission source or from another transmission destination.
2. Description of Related Art
The use of various multi-function peripheral ("MFP") devices having multiple functions such as scanning, printing and copying has become popular in recent years. Some of these MFP devices are capable of not only transmitting image data captured by scanning original document images and attaching the image data to electronic mail ("e-mail") messages, but also capable of developing received image data files attached to e-mail messages into bitmap data and printing said data, so that e-mail printing systems for transmitting such printing data attached to e-mail messages to such MFP devices to be printed have come to be used.
In some cases, however, such an e-mail printing system can create a situation where an MFP at the delivery destination cannot print the attachment file as it is prevented from being transmitted due to the capacity limitation of the relaying mail server. In order to solve the problem, there have been several proposals: a method of breaking down an e-mail message into a plurality of e-mail messages at the transmission source device, if the volume of said message exceeds said capacity limitation and restoring the original message from the divided messages at the transmission destination device (US 2001/0013056 A1); and a method of storing an attachment file at a specified location of the transmission source device, if it cannot be transmitted due to a size limitation, and later accessing and downloading it from the stored location at the transmission destination device (US 2002/0140986 A1). However, there is a problem with the first method in that the process becomes too complicated as it is necessary for the transmission source device to divide the file in advance into smaller divisions according to a preset upper limit, which suits the smallest capacity limit among the mail servers the message has to deal with in its transmission. Also, there is a problem with the latter method in that it may be impossible for the transmission destination device to access the transmission source device due to the network environment of the transmission source device (firewall, etc.) if the transmission destination device cannot receive an e-mail message due to its size and hence it has to access the transmission source device.

Image processing device, image processing method, image processing program, and computer readable recording medium on which the program is recorded


A vehicle speed control system for a vehicle comprises a lateral acceleration sensor, a vehicle speed sensor, a target vehicle speed setting device, a drive system of the vehicle, and a controller connected. The controller is arranged to calculate a correction quantity on the basis of the lateral acceleration and the vehicle speed, to calculate a command vehicle speed on the basis of the vehicle speed, the target vehicle speed, a variation of the command vehicle speed and the correction quantity, and to control the drive system to bring the vehicle speed closer to the command vehicles speed.

The present invention relates to a vehicle speed control system for controlling a vehicle speed, and more particularly to a control system which controls a vehicle so as to automatically cruise at a set vehicle speed.
Japanese Patent Provisional Publication No. (Heisei) 11-314537 discloses a vehicle speed control system which controls a vehicle speed so that an actual lateral acceleration of the vehicle does not become greater than a preset lateral acceleration.


A method of brazing stainless steel components to form a complex shape such as an impeller. The method includes the steps of providing the stainless steel components shaped and formed from a selected stainless steel alloy; providing a brazing alloy having a selected composition and compatibility with stainless steel; heating the stainless steel components and brazing alloy for a controlled time to a liquidus temperature to effect brazing; cooling the stainless steel components and brazing alloy to a quench temperature substantially lower than the liquidus temperature of the brazing alloy to provide a tensile strength of greater than about 20 Ksi in the brazing alloy; and quenching the assembly from the quench temperature to a temperature of less than about 400° F. in a given time to provide a brazed assembly free of distortion and cracks with desired mechanical properties in the stainless steel components by virtue of the thermal treatment.

1. Field of the Invention
This invention generally relates to a method of brazing stainless steel components and, more particularly, to brazing complex shapes of stainless steel. The invention relates to a method of brazing, accompanied by a subsequent controlled cooling and quenching treatment for forming an integral assembly from a plurality of separate stainless steel components of complex geometry to prevent cracking thereof. In addition, the invention relates to an article made in accordance with the method, most preferably, a stainless steel impeller assembly.
2. Background Art
Welded assemblies, such as impellers, are conventionally formed initially from two or more separate parts. For an impeller assembly, one part is called the hub, which may or may not contain integrally machined or welded blades. The other is called the cover, which may or may not contain integrally machined or welded blades. These two parts, with at least one part containing integrally machined or welded blades, have conventionally been joined by a brazing method to form an integral assembly called an impeller. Due to the required mechanical properties of the base materials used, a subsequent cooling and quenching treatment is required.
Traditional brazing methods initiate a quenching treatment at a temperature that is just slightly below the liquid phase of the brazing alloy to ensure that the mechanical properties of the base materials are satisfied. While this traditional method is beneficial to the base materials, there is evidence that the strength of the brazed joint is inadequate at these quenching temperatures and, thus, occasionally results in cracking of the brazed joint. This is particularly true in complex shapes, such as an impeller assembly, having cross-sectional thickness variations which cause thermally induced stress upon cooling.
The problem of brazed joint strength has been addressed in a number of ways. U.S. Pat. No. 5,190,596 to Timsit discloses a method of brazing metal surfaces, which utilizes a mixture of a metal and a brazing flux. The metal of the mixture is adapted to form a brazable eutectic with one or both of the surface metals. U.S. Pat. No. 6,112,971 to Castaldo et al. discloses brazing 304L stainless steel parts using an Ni-13Cr-2.8B-4Si-4Fe brazing alloy. U.S. Pat. No. 6,074,604 to Saito et al. discloses a brazing filler metal for brazing stainless steel at low temperatures so as not to adversely affect the properties of the stainless steel while minimizing brittleness in the brazed joint. The brazing filler metal includes 5% to 30% by weight of Mn or Sn, 20% to 70% by weight of Cu, and inevitable impurities, with the balance being Ni. Each of the cited references, while providing some improvement in brazed joint strength and longevity, do not provide the level of brazed joint strength required for high stress applications, such as, for example, the brazed joints of an impeller. Particular concerns in this regard include the development of cracks of the brazed joint and thermal distortion, which is a problem in brazed impeller assemblies.
There is an established need for a brazing method that can provide impeller assemblies with brazed joints having adequate mechanical properties and that are not prone to cracking of the brazed joint.

Method of brazing and article made therefrom


A new and distinct cultivar of Impatiens plant named ‘Balfiestarsa’, characterized by its double-type salmon-colored flowers with light red-colored mottling, dark green-colored foliage, and vigorous, upright mounded growth habit.

The present invention relates to a new and distinct cultivar of Impatiens plant botanically known as Impatiens walleriana and hereinafter referred to by the cultivar name 'Balfiestarsa'.
The new cultivar originated in a controlled breeding program in Elburn, Ill. during February 2003. The objective of the breeding program was the development of new compact Impatiens cultivars with fully double-type flowers, attractive flower and foliage coloration, and freely branching growth habit.
The new cultivar was the result of a self-pollination of the proprietary Impatiens walleriana breeding selection 3596-3-2, not patented, characterized by its white-colored flowers with coral-colored venation, medium green-colored foliage, and medium vigorous habit. The new cultivar was discovered and selected by the inventor as a single flowering plant within the progeny of the above stated self-pollination during October 2003 in a controlled environment at Elburn, Ill.
Asexual reproduction of the new cultivar by terminal stem cuttings since October 2003 at Elburn, Ill. and West Chicago, Ill. has demonstrated that the new cultivar reproduces true to type with all characteristics, as herein described, firmly fixed and retained through successive generations of such asexual propagation.


A display filter having a secure apparatus comprised of spring loaded gripping members for attaching a bezel having a filter medium onto a notebook computer. Gripping members grasp the sides of the notebook computer and the springs exert force sufficient to hold the display filter at a desired location. Further more, the display filter is horizontally adjustable so that the filter medium may be centered over the notebook computer display. When not used on a notebook computer display, the display filter may be stored in a relatively flat form factor by rotating the gripping members such that the protrusions used to grip the side of a notebook computer case may be rotated so that they lay flat against the side of a bezel. In this manner, there are no protruding edges and overall bulk is minimized. Other ways of attachment include the use of L-shaped strip members that are adjustable with respect to the bezel that contain the filter medium. On the extended portion of the L-shaped strip, there is a curved clip-like structure to snap the bezel into place on the notebook computer case and over the notebook computer display. The elongated portion of the L-shaped strip can be adjusted with respect to the bezel holding the filter medium so that when the display filter is attached to the notebook computer case, the filter medium will be centered over the notebook computer display.

1. The Field of the Invention
This invention relates to screen filters and filter bezels for monitors, computer screens, and other visual displays. More particularly, this invention deals with ways of securing screen filters and filter bezels to PC workstation monitors and notebook computer displays.
2. Present State of the Art
Currently there exists a plethora of different viewing devices encountered by many people through all walks of life. These include television screens, computer monitors, ATM machines, some sophisticated copy machines, portable laptop and notebook computer screens, to name just a few. While many of these viewing screens are based on cathode ray tube (CRT) technology, increasingly, use has been made of Liquid Crystal Display (LCD) and gas plasma technologies that advantageously reduce bulk since no tube is required. The newer technologies provide thin, flat screen viewing spaces. This is particularly relevant in applications where portability and light weight are important. Particularly important for purposes of this disclosure are personal computing applications where portable laptop and notebook computers utilize a variety of flat-screen technologies in their screen or monitor systems.
In the personal computer industry, certain problems have been identified with constant and extended viewing of PC monitors and other screens. Some problems associated with extended computer screen viewing include eye strain and headaches, drowsiness, blurred vision, dry and irritated eyes, and a sensitivity to light. These problems are thought to be caused by radiation, ultra-violet (UV) light, infra-red (IR) light, glare, poor contrast, and bothersome reflections. In an attempt to address these problems products have been developed to filter screen output before being perceived by the human eye in an effort to alleviate or eliminate the above-mentioned concerns. Such filters have been known to filter out UV and IR transmissions from a visual screen, as well as to prevent glare and reflection from distorting or otherwise making screen output difficult to view. While plastics, fine screens, and other lightweight materials have been utilized to construct filters to prevent distortions and filter unwanted radiation, it has been found that high-quality optical glass tends to be the most effective. One drawback in the use of such high quality glass filters for portable computing applications is their increased weight and expense.
Other types of filters can be used for privacy. Privacy filters find application in any situation where information security may be compromised. Still other filters are used to enhance contrast of actual screen output. The contrast enhancement is found in many filters and is in part achieved by reducing glare and reflection.
While many filtering solutions exist for desk-top computer monitors, little has been done to address the problems peculiar to portable computers. Among these problems are a requirement for easy portability, the ability to adjust to a number of different display placement configurations within a notebook computer case, and the ability to easily position or remove the filter on the notebook case as desired by the user. It would be desirable to achieve all of these and other objectives in constructing filters and filter securement systems for notebook computers.
Portability is required since a notebook computer is designed to be folded into a, minimal size to travel with the user. Notebook computer manufacturers have so constructed their machines to optimize all possible space in order to make the folded notebook computer form factor as small as possible. Therefore, unlike the situation with desk-top computer monitors where the filter securement assembly may remain relatively permanently affixed to the monitor casing, a portable notebook or laptop user will install the filter assembly or bezel each time the computer is used since there will not normally be room to leave a filter bezel affixed to the notebook display when the notebook computer is folded for storage and travel. Because the filter assembly will be stored separate from the notebook computer, it is necessary for the filter assembly to be durable, compact, and have a minimum of protruding edges when stored for traveling. It must also have a small overall form factor so as to minimize the bulk and awkwardness.
Next, a filter securement assembly must be quick and easy to use. Because a traveller with a notebook computer may be utilizing the computer for presentations or other quick set-up situations, easy-to-use mechanisms for attaching the filter to the notebook screen area are necessary. This can be contrasted with mechanisms used to attach filters to desk-top computer monitors that will remain affixed to the monitor once installed rather than be repeatedly attached and detached each time the computer is used as is the case with notebook and other portable computers.
Finally, a filter assembly for notebook computers must be able to adjust to a number of different display positions that may be found within the notebook computer casing. For example, a display screen may be housed horizontally centered within a notebook casing or it may be offset to one side of the computer housing. Rather than designing a separate filter securement assembly for each model of notebook computer, it is desirable that the filter securement assembly itself be adjustable to the different vertical and horizontal placement possibilities of a notebook computer screen within the notebook. In this way, filters can be produced according to notebook computer display size taking no concern as to actual placement of the display screen with respect to the casing being unimportant.
One known way of attaching a filter to a notebook computer screen utilizes four adhesively applied patches of Velcro, one patch at each corner of the casing around the notebook screen. Mating patches of Velcro are found on a filter bezel holding a filter medium that allows the filter assembly bezel to be placed on the Velcro when desiring to attach it for normal use. This method of securement does not allow a filter to be attached to an unprepared notebook computer but only those computers that have the adhesively applied patches of Velcro previously applied. Further, there may be some notebook computer configuration where the adhesively applied Velcro patches may interfere with closing the notebook computer for storage and traveling.
What is needed is a filtering apparatus for notebook computers that allow quick, easy, and secure placement of a filtering medium over the notebook computer display regardless of where the display is located vertically or horizontally. Furthermore, such securement apparatus must be portable and capable of enduring the rigors of travel.

Display filter and bezel securement apparatus


In the plasma processing apparatus 10, a processing space S is formed between a susceptor 12 and an upper electrode 13 facing the susceptor 12. The plasma processing apparatus 10 includes a magnetic field generating unit provided at a side of the upper electrode 13 opposite to the processing space S. The magnetic field generating unit includes a magnetic force line generating unit 27 having a pair of annular magnet rows 27a and 27b. The annular magnet rows 27a and 27b are provided at the side of the upper electrode 13 opposite to the processing space S and arranged concentrically when viewed from the top. In the magnetic force line generating unit 27, an angle θ1 formed by axial lines of magnets of the annular magnet rows 27a and 27b is set to be in a range of about 0°<θ1≦180°.

There is known a capacitively coupled plasma processing apparatus configured to generate plasma in a processing space between circular plate-shaped upper and lower electrodes arranged parallel to each other and to perform a required process on a substrate such as a semiconductor wafer (hereinafter, simply referred to as a "wafer") by the plasma. In such a capacitively coupled plasma processing apparatus, plasma density corresponding to a central portion of the upper electrode or the lower electrode is increased, and plasma density distribution in the entire processing space tends to become non-uniform.
To solve the problem, the present inventors have proposed a plasma processing apparatus 115 as depicted in FIG. 10 (see, for example, Patent Document 1). In this plasma processing apparatus 115, an upper electrode is divided into an inner electrode 110 and an outer electrode 111 surrounding the inner electrode 110. High frequency powers are independently applied to the inner electrode 110 and the outer electrode 111, and an electric field in a processing space (hereinafter, referred to as an "inner space") corresponding to the inner electrode 110 and an electric field in a processing space (hereinafter, referred to as an "outer space") corresponding to the outer electrode 111 are also individually controlled. Further, permanent magnet rows 112 to 114 are concentrically arranged on a top surface of the upper electrode about the center of the upper electrode, and a magnetic field is generated at a desired position within the processing space.
In this plasma processing apparatus 115, by individually adjusting the electric field in the inner space and the electric field in the outer space, plasma density in the inner space and plasma density in the outer space are independently controlled.
Further, in the plasma processing apparatus 115, circular ring-shaped magnetic force lines 116 and 117 concentrically distributed about the center of the upper electrode are respectively generated between the permanent magnet rows 112 and 113 and between the permanent magnet rows 113 and 114. Magnetic fields generated by these magnetic force lines 116 and 117 are formed in the inner space and in the outer space, and electrons within the inner space and the outer space are drifted by a Lorentz force in directions orthogonal to the magnetic force lines 116 and 117 (in the drawing, marks such as '●' indicate drift directions of the electrons). At this time, the electrons drifted by the Lorentz force revolve around the center of the upper electrode at the vicinity of the surface of the upper electrode. The revolving electrons collide with molecules and atoms of a processing gas, and thus, plasma is generated. As a result, circular ring-shaped plasma distributed about the center of the upper electrode can be generated so as to correspond to the magnetic field.
In this plasma processing apparatus 115, the plasma density in the inner space and the plasma density in the outer space are independently controlled, and a multiplicity of circular ring-shaped plasma is generated. As a result, plasma density distribution in the entire processing space can be effectively controlled.
Patent Document 1: Japanese Patent Laid-open Publication No. H10-152775
However, the present inventors have conducted researches repeatedly and found out that the conventional plasma processing apparatus has the following issues. The magnetic field generated in the processing space has a horizontal component parallel to the upper and lower electrodes and a vertical component perpendicular to the upper and lower electrodes. The horizontal component is effectively used for controlling the plasma density within the processing space by individually controlling the electric field and the magnetic field. However, the vertical component complicates the relationship between the magnetic field and the electric field in the processing space, and the plasma density distribution in the processing space may not be controlled.


When a braking/driving force on each wheel is used for vehicle motion control, in order to reduce a noise generated by a zero cross of a motor torque, provided is a distribution setting part, which is to be applied to a vehicle configured so that a conversion rate of converting a braking/driving force on the wheel into a force in a vertical direction of a body by a suspension is different between a front wheel side and a rear wheel side. The distribution setting part sets distributions of a driver-requested driving force to front/rear wheels so as to be larger to the wheels coupled to the suspensions smaller in conversion rate than to the wheels coupled to the suspensions larger in conversion rate. As a result, a zero cross of a motor torque is restrained, resulting in a reduction in generation of a noise caused by a backlash of speed reduction gears.

1. Field of the Invention
The present invention relates to a vehicle braking/driving force control apparatus for independently controlling a driving force and a braking force of each of front left and right and rear left and right wheels of a vehicle.
2. Description of the Related Art
Hitherto, there has been known a vehicle braking/driving force control apparatus for independently controlling a driving force and a braking force (both are collectively referred to as braking/driving force) for front left and right and rear left and right wheels of a vehicle. For example, there has been known a vehicle of an in-wheel motor type as a form of an electric vehicle, in which a motor is arranged inside or closely to the wheel of the vehicle, and the wheel is directly driven by the motor. In the vehicle of the in-wheel motor type, each motor is individually controlled for power running or regeneration, and a driving torque or a braking torque applied to each wheel is thus individually controlled, thereby generating a braking/driving force on each wheel.
Each wheel is suspended via a suspension to a vehicle body. In general, as illustrated in FIGS. 2A and 2B, an instantaneous rotation center Cf of a suspension for coupling a front wheel 10f to a vehicle body B is positioned behind and above the front wheel 10f, and an instantaneous rotation center Cr of a suspension for coupling a rear wheel 10r to the vehicle body B is positioned ahead of and above the rear wheel 10r. Therefore, as illustrated in FIG. 2A, when a driving torque is applied to the front wheel 10f, a force Ff1 forward in a travel direction of the vehicle acts at a ground contact point of the front wheel 10f, and a vertical force Fzf1 biasing the vehicle body B downward is generated by the force Ff1 at the ground contact point of the front wheel 10f. Thus, the force in the direction of sinking the vehicle body B acts as a result of the driving of the front wheel 10f. In contrast, as illustrated in FIG. 2B, when a braking torque is applied to the front wheel 10f, a force Ff2 backward in the travel direction of the vehicle acts at the ground contact point of the front wheel 10f, and a vertical force Fzf2 biasing the vehicle body B upward is generated by the force Ff2 at the ground contact point of the front wheel 10f. Thus, the force in the direction of raising the vehicle body B acts as a result of the braking of the front wheel 10f.
On the other hand, the generation direction of the vertical force on the rear wheel 10r is opposite to that for the front wheel 10f. In other words, as illustrated in FIG. 2A, when a driving torque is applied to the rear wheel 10r, a force Fr1 forward in the travel direction of the vehicle acts at a ground contact point of the rear wheel 10r, and a vertical force Fzr1 biasing the vehicle body B upward via the suspension is generated by the force Fr1 at the ground contact point of the rear wheel 10r. Thus, the force in the direction of raising the vehicle body B acts as a result of the driving of the rear wheel 10r. In contrast, as illustrated in FIG. 2B, when a braking torque is applied to the rear wheel 10f, a force Fr2 backward in the travel direction of the vehicle acts at the ground contact point of the rear wheel 10r, and a vertical force Fzr2 biasing the vehicle body B downward via the suspension is generated by the force Fr2 at the ground contact point of the rear wheel 10r. Thus, the force in the direction of sinking the vehicle body B acts as a result of the braking of the rear wheel 10r.
In this way, a part of the longitudinal braking/driving force on the wheel is converted by the suspension into the force in the vertical direction of the body B. Thus, motion control (including a body attitude control such as restraint of a roll motion, a pitch motion, and a heave motion) for the vehicle can be carried out by controlling a braking/driving force on the each wheel. Therefore, a target braking/driving force on the each wheel is calculated as a resultant force of a driver-requested distributed driving force acquired by distributing a driver-requested driving force set in response to an operation amount by a driver to the each wheel and a control braking/driving force for carrying out the motion control for the vehicle.
Based on this view point, for example, a vehicle travel control apparatus proposed in Japanese Patent Application Laid-open No. 2009-143310 controls a braking/driving force of each in-wheel motor to restrain a roll motion of the vehicle.
By the way, when the motion control for the vehicle is carried out by the braking/driving forces on the wheels, the direction of the target braking/driving force may be inverted depending on the motion state of the vehicle. For example, while the control braking/driving force is opposite in direction to the driver-requested distributed driving force, when a relationship in magnitude between both forces changes, the direction of the target braking/driving force is inverted. In this case, the motor is switched from a state (powering) where the driving force is generated on the wheel to a state (regeneration) where the braking force is generated on the wheel, or is switched from the state (regeneration) where the braking force is generated on the wheel to the state (powering) where the driving force is generated on the wheel. Thus, an inversion of the motor torque (so-called zero cross of the motor torque) occurs. Therefore, when the motor torque is transmitted via speed reduction gears to the wheel, a noise is generated when a backlash is taken up by the inversion of the motor torque.

Vehicle braking/driving force control apparatus