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System And Method For Resonance Frequency Tuning Of Resonant Devices - Patent 8154176
BACKGROUND The present disclosure relates to methods for tuning the stiffness of a structure, and in particular to methods for tuning the stiffness of a structure by changing the shape of the structure, including, for example, changing the shape of thestructure by piezoelectric means. The disclosure further relates to methods for resonance frequency tuning of resonating structures, such as for example, vibration energy scavengers. Furthermore it relates to tunable devices, such as vibration energyscavengers or sensors. Future wireless sensor networks may comprise sensor nodes which occupy a volume of typically a few cm.sup.3. The scaling down of batteries for powering such sensor nodes faces technological restrictions as well as a loss in storage density. For this reason, it would be desirable to replace batteries with more efficient, miniaturized power sources. Energy scavengers based on the recuperation of wasted ambient energy are one possible alternative to batteries. Several scavenger concepts havebeen proposed, including concepts based on the conversion of thermal energy, pressure energy, or kinetic energy. Kinetic energy scavengers or vibration energy scavengers convert energy in the form of mechanical movement (e.g. in the form of vibrations or random displacements) into electrical energy. For conversion of kinetic energy into electrical energy,different conversion mechanisms may be employed, such as, for example, conversion mechanisms based on piezoelectric, electrostatic, or electromagnetic mechanisms. Piezoelectric scavengers employ active materials that generate a charge when mechanicallystressed. Electrostatic scavengers utilize the relative movement between electrically isolated charged capacitor plates to generate energy. Electromagnetic scavengers are based on Faraday's law of electromagnetic induction, and generate electricalenergy from the relative motion between a magnetic flux gradient and a conductor. A vibration energy scavenger has th
Induction Motor Lamination Design - Patent 8154167
The present invention relates generally to electric motors and, more particularly, to a lamination design that achieves improved flux distribution for improved efficiency, torque density and high speed power.BACKGROUND OF THE INVENTION The trend towards designing and building fuel efficient, low or zero emission on-road and off-road vehicles has increased dramatically in recent years, with significant emphasis being placed on the development of hybrid and all-electricvehicles. This has led, in turn, to a greater emphasis being placed on electric motors, either as the sole source of propulsion (e.g., all-electric vehicles) or as a secondary source of propulsion in a combined propulsion system (e.g., hybrid or dualelectric motor vehicles). The electric motor in such an application may utilize either an AC or DC permanent magnet motor design or an AC induction motor design. Regardless of the type of electric motor, it must be designed to achieve the desiredefficiency, torque density and high speed torque with an acceptable motor size and weight. In a multi-phase AC induction motor, a rotating magnetic field is generated by a plurality of circumferentially distributed multi-phase coil windings secured within a plurality of circumferentially distributed slots in the inner periphery of themotor's stator, the coil windings being coupled to a multi-phase AC power source controlled with certain desired frequencies and certain desired levels of voltage or current in each phase. The magnetic field generated within the stator core inducesmultiple-phase alternating currents in the rotor windings which in turn interact with the stator magnetic field. The resultant rotating field causes the desired shaft torque and rotation of the motor's rotor at the desired speed, the rotor beingcomprised of one or more magnetic pole pairs with the same number of pole-pairs as that of the stator windings of each phase. For decades AC induction motors have been the work-horses of modern soc
Dual Layer Winding Pattern - Patent 8154166
The present invention relates generally to electric motors and, more particularly, to a winding pattern that achieves the benefits of lap winding and concentric winding.BACKGROUND OF THE INVENTION The trend towards designing and building fuel efficient, low emission vehicles has increased dramatically over the last decade, with significant emphasis being placed on the development of hybrid and all-electric vehicles. This has led, inturn, to a greater emphasis being placed on electric motors, either as the sole source of propulsion (e.g., all-electric vehicles) or as a secondary source of propulsion in a combined propulsion system (e.g., hybrid or dual electric motor vehicles). AC induction motors are well known and are used in a variety of applications ranging from industrial to automotive. In such a motor, a magnetic field is generated by a plurality of circumferentially distributed coil windings secured within aplurality of circumferentially distributed slots in the inner periphery of the motor's stator, the coil windings being coupled to an AC power source. The magnetic field generated within the stator core causes rotation of the motor's rotor, the rotorbeing comprised of one or more magnetic pole pairs. In general, the coil windings of the stator are divided into phases with the number of phases typically equaling the number of phases of the power supply. Each phase of the coil windings is then arranged into coil groups, with each coil grouprepresenting a single pole of a single phase. Each coil group is comprised of one or more individual coils or coil windings. Thus a typical winding pattern for a single phase, two-pole induction motor will include two coil groups while a three-phase,two-pole induction motor will include six coil groups. The manner in which the individual coil windings of the coil groups are arranged within the slots of the stator will determine, in part, the performance characteristics of the motor as well as itsmanufacturing cost.
Sensing Device - Patent 8154175
BACKGROUND This disclosure relates to sensing device that uses a mechanical snap mechanism and a resistive sensing element. A wide variety of sensing devices are used to perform, for example, position sensing. When simple, low cost position sensing is desired, a position indicating electrical switch is often used. Switches can exhibit poor reliability in typicalaerospace applications, particularly due to sensitivity to contamination of electrical contacts and deterioration within the switch from vibration. Aerospace applications in particular demand reliable switch operation. Continuously monitoring health ofthe switch contacts is impractical since electrical switches typically have make/break contacts. Thus, switch failures often occur without any prior warning.SUMMARY A sensing device is disclosed that includes a bistable snap mechanism having a snap element operatively connected to an input element and an output element. The snap element has two discrete positions that provide the output element in one offirst and second positions. A resistive sensing element includes a flexible member operatively connected to the output element and is configured to deflect in response to movement of the output element between the first and second positions. A resistoris mounted on the flexible member and is configured to provide a variable resistance based upon deflection of the flexible member. In one example, the resistive sensing element includes a generally circular base providing an opening. The flexible member extends from the base into the opening and is configured to deflect relative to the base. A piezoresistor is mounted onthe flexible member and is configured to provide a variable resistance based upon deflection of the flexible member. An example method of sensing an input includes receiving an input. The output element moves in response to the input. The flexible member deflects in response to the output element moving, and the resistance of a resistor v
Boundary Acoustic Wave Device - Patent 8154171
This application is a U.S. NationalStage Application of the PCT International Application No. PCT/JP2008/002976.TECHNICAL FIELD This invention relates to a boundary acoustic wave device for use in, for example, a mobile telephone.BACKGROUND ART FIG. 4 is a cross-sectional view of conventional boundary acoustic wave device 501 described in Patent Document 1. This device includes medium layer 1 made of LiNbO.sub.3, medium layer 2 made of SiO.sub.2 stacked on medium layer 1, andinterdigital transducer (IDT) electrode 3 made of Au formed at interface 501A between medium layers 1 and 2. In boundary acoustic wave device 501, an SH type boundary acoustic wave as a main mode propagates along interface 501A between medium layers 1and 2. The boundary acoustic wave propagates and displaces medium layers 1 and 2. In boundary acoustic wave device 501, an area in which medium layer 2 made of SiO2 is displaced is larger than an area in which medium layer 1 made of LiNbO.sub.3 isdisplaced. This structure prevents the boundary acoustic wave from concentrating at interface 501A, and accordingly, prevents the device from exhibiting superior piezoelectric characteristics of LiNbO.sub.3 of medium layer 1, i.e., prevents the devicefrom having a large electro-mechanical coupling coefficient. Patent Document 1: WO 2004/095699SUMMARY OF THE INVENTION A boundary acoustic wave device includes a first medium layer made of piezoelectric material, a second medium layer provided on the first medium layer, a third medium layer provided on the second medium layer, and an electrode provided at aninterface between the second and third medium layers. The electrode drives the third medium layer to generate a transverse wave. A propagation speed of the transverse wave in the third medium layer is lower than a propagation speed of the transversewave in the first medium layer. A propagation speed of the transverse wave in the second medium layer is lower than the propagation speed of the transver
Bending Transducer Device For Generating Electrical Energy From Deformations And Circuit Module - Patent 8154174
1. Field of the Invention The present invention relates to a bending transducer device for generating electrical energy and a circuit module. 2. Description of Related Art For applications of low power consumption, it is known to use piezoelectric materials for the power supply which generate electrical energy from surrounding energies, in particular from vibrations and deformations (also referred to as "energyharvesting"). The deformations may be converted into electrical energy with the aid of a bending transducer device. Such a bending transducer device which has an elastically deformable support structure and a bearing device in addition to apiezoelectric element is disclosed in published German patent document DE 10 2007 006 994. The piezoelectric element is designed and situated on the support structure in such a way that, due to a deformation of the support structure caused byvibrations, the piezoelectric element is deformable, the support structure being supported vibration-capably in the bearing device. The voltage generated by deforming the piezoelectric element may be picked up via a metal coating on both the top and thebottom of the piezoelectric element. The bending transducer device is part of a circuit module which is usable as an energetically self-sustaining sensor module for measuring a pressure and/or a temperature and/or an acceleration of a tire. An important criterion for the usability of such bending transducer devices, in particular as a component of an above-described circuit module, is their long service life. During use in a tire in particular, such a bending transducer device isexposed to high mechanical stresses. The bearing, in particular, in which the support structure is supported, is exposed to mechanical stresses. Such stresses are generated by the vibration of the support structure. If the support structure is fixedlyrestrained, or as in published German patent document DE 10 2007 006 994 supported in a groove of the ho
Miniature motor Horng et al Alex Horng Tso Kuo Yin Application number 12 645 580 Electrical Generator Or Motor Structure
1. Field of the Invention The present invention relates to a miniature motor and, more particularly, to a miniature motor that can be started easily. 2. Description of the Related Art Conventional motors generally include a base, a rotor and a stator unit. The base includes a shaft tube to which the rotor is rotatably mounted. The stator unit is mounted to the base and comprised of a plurality of silicon steel plates and aplurality of coils. The rotor can be driven by a magnetic field created by the stator unit when supplied with electricity. However, difficulties and dead angles exist during starting of the motors. Easy-to-start designs for motors have been proposedto solve these problems. FIG. 1 shows a conventional motor including a rotor 82 and a stator 8 having a plurality of stacked silicon steel plates 81. Each silicon steel plate 81 includes a plurality of radial extensions 811 each having a pole shoe 812 at a distal endthereof Each pole shoe 812 has two sections on opposite sides of a central line of the pole shoe 812. The sections are asymmetric to each other relative to the central line to provide a shift of magnetic flux. Thus, the stator 8 can create anasymmetric magnetic path to change the waveforms of the output torque while starting a rotor, eliminating dead angles of starting. An example of such a structure is disclosed in Taiwan Patent No. I221048. However, the asymmetric shape of the pole shoes812 of the stator 8 renders a complicated structure as well as difficulties in manufacturing the silicon steel plates 81, increasing the manufacturing costs. Furthermore, the asymmetric pole shoes 812 increase the gap between the stator 8 and the rotor82, adversely affecting the operational efficiency of the motor. Further, the stator 8 comprised of the silicon steel plates 81 has a certain axial height and a complicated structure, resulting in difficulties in designs of compact, miniature motors. Taiwan Patent Publication No. 505337 discloses
Electronic Circuit For Highly Efficient Driving Of Piezoelectric Loads - Patent 8154172
The present disclosure relates to an electronic circuit for highly efficient driving of piezoelectric loads, comprising a driver circuit portion coupled to at least one load terminal by means of an inductive-resistive connection whereon avoltage waveform is applied. The present disclosure relates also to a method for driving a piezoelectric load with inductive-resistive connection. The present disclosure relates particularly, but not exclusively, to a driver circuit adapted to followthe current profile required by a piezoelectric printer head coupled to the driver circuit by means of an inductive and resistive cable referred to as flat cable and similar to a resistance and to a series inductor.BACKGROUND As is well known in this specific technical field, a wide range of transducers are available such as, for example, those described in the U.S. Pat. No. 5,895,998. Various types of printer heads are among the wide variety of disclosedtransducers. In a piezoelectric load such as a printer head, the electronic circuit is driven by applying voltage waveforms generally formed by a series of ramps having a predetermined slew-rate. An example of such an application is disclosed in theU.S. Pat. No. 4,767,959 in the name of Nippondenso Co. The special accuracy required for applying said voltage waveform to the load terminals, along with the high frequency of the driver signal, leads to the use of linear-mode driver circuits involving high power dissipation. Moreover, the presenceof a parasitic inductance in the flat connection cable to the load, which is coupled in series to the real capacitive load, requires the current demanded by the load to be filtered. The profile of this current is not rectangular and has a beveledpattern with over- and under-elongations, to produce a voltage waveform as shown in the attached FIG. 1. Therefore, with respect to an ideal case of a merely capacitive load, it is necessary to manage adequately a current slew-rate at the ramp ba
Acoustic Wave Device And Method For Manufacturing The Same - Patent 8154170
This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2008-217062, filed on Aug. 26, 2008, the entire contents of which are incorporated herein by reference.FIELD A certain aspect of the embodiments discussed herein is related to an acoustic wave device and a method for manufacturing the same.BACKGROUND An acoustic wave device may be provided in wireless communication devices, which may typically be portable phones. The acoustic wave device has an acoustic wave element formed on a piezoelectric substrate. The acoustic wave device has afunction area in which an acoustic wave is excited by the acoustic wave element. Such a function area may include an interdigital transducer (IDT). An opening is defined above the function area because the acoustic wave is excited. An acoustic wave device utilizing a wafer-level packaging scheme directed to downsizing is described in Japanese Laid-Open Patent Publication No. 2006-324894. FIG. 1 of this publication describes the following acoustic wave device. Apiezoelectric substrate 100 has a function area (comb electrodes 110), which is sealed with a resin part (composed of a cavity forming layer 210 and a seal region 230) so as to define a cavity 320 above the function area. An electrode pad (pad electrode120) electrically connected to the acoustic wave element is formed on the piezoelectric substrate. An opening is formed in the resin part above the electrode pad. The opening is full of a metal layer (electrically conductive via 430). An externalcircuit may be connected to the acoustic wave element via the metal layer and the electrode pad.SUMMARY According to an aspect of the present invention, there is provided an acoustic wave device including: a piezoelectric substrate on which an acoustic wave element and an electrode pad connected to the acoustic wave element are formed; a firstresin part having a first opening located above a function area in which an acous
Drive Device Control Unit - Patent 8154160
INCORPORATION BY REFERENCE The disclosure of Japanese Patent Application No. 2008-040376 filed on Feb. 21, 2008 including the specification, drawings and abstract is incorporated herein by reference in its entirety.BACKGROUND The present invention relates to a drive device control unit. A drive device control unit that is integrally fixed to a drive device has been recently developed as a control unit of a drive device having a rotating electrical machine (a motor and a generator) for use in an electric vehicle, a hybridvehicle, and the like (e.g., see, for example, Japanese Patent Application Publication No. JP-A-2003-199363 (pages 5 to 7, FIG. 1)). There is a demand for TIUI drive device control unit to have improved reliability by assuring resistance to thevibration of a drive device and to have a reduced size, a reduced weight, a reduced number of parts, and improved manufacturability. In order to meet such demands, a drive device control unit described in Japanese Patent Application Publication No. JP-A-2003-199363 (pages 5 to 7, FIG. 1) is a unit accommodating an inverter for driving a rotating electrical machine included ina drive device and includes a control substrate that controls the drive device. The drive device control unit includes a case for mounting a switching element power module of the inverter, a capacitor bracket for mounting a smoothing capacitor for theinverter, and a control substrate bracket for mounting the control substrate. The capacitor bracket is fixed to the case and the control substrate bracket is fixed to the capacitor bracket.SUMMARY The above drive device control unit includes two brackets: the capacitor bracket for fixing the smoothing capacitor; and the control substrate bracket for fixing the control substrate. In other words, the control substrate bracket having aplanar substrate-fixing surface is provided separately from the capacitor bracket having a top surface of a complicated convexo-concave shape corresponding to t
Electric Power Collection/distribution Ring Of Rotary Electric Machine - Patent 8154163
Priority is claimed on Japanese Patent Application No. 2008-105539, filed Apr. 15, 2008, and Japanese Patent Application No. 2008-105540, filed Apr. 15, 2008, the contents of which are incorporated herein by reference.FIELD OF THE INVENTION The present invention relates to an electric power collection/distribution ring (connection structure for electric power collection/distribution) of a rotary electric machine.DESCRIPTION OF THE RELATED ART Heretofore, for example, there has been known a motor in which a plurality of concentrated winding stator coils is connected by means of fusing (thermal caulking) into a ring shaped bus ring. In this motor, the connection between the pluralityof concentrated winding stator coils and the ring shape bus ring is achieved by: arranging wire connection members so as to be adjacent to U-shape curved terminal sections in the circumferential direction, the terminal sections protruding from the busring in the axial direction thereof; connecting one ends of the terminal sections to one ends of the wire connection members by means of fusing; and connecting the stator coil to other ends of each of the wire connection members by means of fusing (forexample, refer to Japanese Unexamined Patent Application, First Publication No. 2004-96841). Moreover, conventionally, there has been known a collection/distribution member of a three phase motor in which three polygonal ring shaped bus bars, to which winding wires corresponding to the phases are to be connected, are held to each otherby three types of clips made of synthetic resins in a state where the bus bars are coaxially arranged (for example, refer to Japanese Unexamined Patent Application, First Publication No. 2007-14083). In this collection/distribution member, a first clip is attached to a straight line section of each polygonal ring shaped bus bar from the radially outer side toward the radially inner side. Moreover, to connection end sections of these busbars, there are attached
System And Method For Device Suspension And Wireless Power Transmission - Patent 8154164
FIELD The field of the invention relates electronics. In particular, the invention relates to a system and method for device suspension and wireless power transmission.BACKGROUND A number of prior magnetic suspension devices demonstrate a floating object with no visible support. Magnetic levitation or suspension can be accomplished in an active system using an electromagnet, position sensor, and feedback controlcircuit. Levitation or suspension is maintained in the system by increasing the lifting current in the electromagnet when the object falls away from the electromagnet and decreasing the lifting current when the object moves up towards the electromagnet. Although position sensors are used to aid in maintaining levitation or suspension, horizontal stability remains a challenge. Additionally, the distance at which an object can be stably suspended has been limited by the amount of power the electromagnetmust output. Inductive transference of energy or power has been used for many years in the form of transformers in switched mode power supplies. Wireless power has also become a very attractive solution with the proliferation of portable devices in recentyears. One popular application has been wireless inductive charging of portable devices, as it may not be safe or convenient for the device to have a physical rather than wireless connection.SUMMARY A system and method for device suspension and wireless power transmission are disclosed. According to one embodiment, an apparatus, comprises a suspended object having a viscous fluid and a wireless receiving circuit. A wireless transmissioncircuit is configured to transmit power to the wireless receiving circuit housed in the suspended object. A magnetic stabilization mechanism is beneath and not in contact with suspended object. A circuit is configured to magnetically control a positionof the suspended object. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included as part of the pr
Motor And Disk Drive Apparatus Provided With A Circuit Board With Wirings - Patent 8154162
The present invention relates to a motor for holding a disk with an opening used in mounting the disk to the motor (hereinafter referred to as a "mounting opening") and a disk drive apparatus provided with the motor.BACKGROUND OF THE INVENTION Conventionally, a motor having a chucking unit for removably holding an optical disk such as a DVD or the like is provided with a circuit board through which an electric current is supplied to the coils of a stator. Along with the sizereduction of a disk drive apparatus, attempts have been made to reduce the size of motor. The reduction in size of the motor makes it necessary to reduce the area of the circuit board. Furthermore, the reduction in price of the disk drive apparatusmakes it inevitable to reduce the motor price. As one approach to the motor price reduction, there is known a method by which the price of a circuit board is reduced by using only one surface of the circuit board. One example of the conventional motors that include a chucking unit and makeuses of only one surface of a circuit board is disclosed in, e.g., Japanese Patent Laid-open Publication No. 10-248190. In recent years, an increase in the writing speed of a disk leads to an increase in the rotation speed of a motor that holds the disk in place. One method of increasing the motor rotation speed is to increase the electric current supplied tocoils. Since the space required in forming wiring lines of a circuit board is reduced along with the size reduction of the circuit board, however, it is impossible to increase the electric current supplied to the coils. In other words, the sizereduction of the circuit board results in the reduction of a permissible current value in the wiring lines of the circuit board, thereby limiting the electric current supplied to the coils. In particular, since only one surface of the circuit board isused for the purpose of motor price reduction, the space required in forming the wiring lines is remarkably reduced by
Fixing Enhancement Mechanism For Large Iron Core - Patent 8154168
The present invention relates generally to a motor, and more particularly to a fixing enhancement mechanism for large iron core. FIG. 1 shows an iron core 1 of a conventional large-size motor for winding a winding coil thereon. In manufacturing, due to the limitation of the large size, the iron core 1 is generally divided into multiple arc-shaped blocks 1a to facilitateprocessing. FIG. 2 shows a measure for assembling the arc-shaped blocks 1a into the iron core 1. The arc-shaped blocks 1a are connected and assembled into a complete ring-shaped iron core 1 with their curvature centers coinciding with each other. Afterassembled, the iron core 1 is fixedly enclosed in a tubular housing 2. Such measure is able to accurately and firmly fix the iron core 1. However, it is necessary to manufacture an even larger housing for accommodating the iron core 1. This leads toincrement of manufacturing cost and troublesomeness in assembling process. Moreover, with the housing 2 as a component of the motor, the heat generated by the motor in operation will be hindered by the housing 2 from dissipating outward. As a result,the operation efficiency will be affected due to poor heat dissipation efficiency. FIG. 3 shows another conventional measure for fixing the iron core 1 without resulting in heat dissipation problem. Two end rings 3 are coaxially fixedly connected to two axial ends of the iron core 1 to hold and lock arc-shaped blocks 1atogether. Such fixing measure simply applies an axial force to the iron core 1 and only provides very little component force normal to the axis of the iron core 1. Therefore, it is necessary to further clamp the end rings 3 and the iron core 1 with twoend boards 4. In addition, several circular rods 5 are bridged and locked between the end boards 4 to enhance the fixing force of the end rings 3 to the iron core 1. The additional end boards 4 leads to increment of manufacturing cost. Furthermore,the end boards 4 still mainly apply an ax
Rail Brush Assembly With Detent - Patent 8154169
This non-provisional patent application claims priority under 35 U.S.C. .sctn.119(a) from Patent Application No. 200810142386.4 filed in The People's Republic of China on Aug. 18, 2008.FIELD OF THE INVENTION This invention relates to an electric motor and in particular, to a rail guided brush assembly for an electric motor, especially for a PMDC motor.BACKGROUND OF THE INVENTION Rail guided brush assemblies are known, see for example, EP1592112. Rail brush assemblies comprise a pair of rails and a brush having two grooves on opposite sides thereof. The brush slides along the rails towards the commutator of the motorurged by a spring and captured by the rails being located within the grooves. One problem with this arrangement is that at end of life, the brushes can dislodge from the rails and cause a short circuit within the motor which could lead to catastrophic failure.SUMMARY OF THE INVENTION Hence there is a desire for an electric motor having a guided brush assembly in which, at end of life, the brush, when worn out (reaches end of useful life), remains captured within the brush guidance system. This is achieved in the present invention by using a rail brush guidance system in which there is a detent mechanism between the rail and the brush spring to prevent the brush from being released from the rails even when the brush has reachedthe end of its useful life (worn out). Accordingly, in one aspect thereof, the present invention provides a rail brush assembly for an electric motor having a commutator, comprising: a brush, having a groove on each of a pair of opposite sides thereof; a pair of rails disposed in thegrooves for guiding the brush to the commutator, the brush being freely slidable along the rails within a predetermined range of motion; a spring arranged to urge the brush along the rails towards the commutator, the spring engaging an end of the brushremote from the commutator; and a detent between the spring and at least one rail to limit the range
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