Abstract: An air-conditioning system for a vehicle, including a refrigerant circuit and an engine, has a battery, a compressor, an electric motor and a load torque control mechanism. The battery supplies electric power. The compressor is operative to compress refrigerant gas for the air-conditioning system. The electric motor is electrically connected to the battery. The motor is driven due to the electric power, and is operatively coupled to drive the compressor when the motor is energized. The load torque control mechanism responsive to the operating condition of the engine to control the load torque of the compressor below a predetermined value during times when the motor is driving the compressor.

Abstract: An air-conditioning system for a vehicle including a refrigerant circuit and an engine, has a compressor in the refrigerant circuit, a battery, an electric motor and a mechanism operative to controllably connect and disconnect a power transmitting path between the engine and the motor. The motor is connected to drive the compressor when energized by the battery. A first controller is operative to control the electric power supplied to the motor from the battery. A capacity control mechanism is responsive to the controller to maintain the discharge capacity of the compressor below a predetermined value upon starting the engine by the motor.

Abstract: An electric compressor includes a motor and a compression mechanism that is driven by the motor. The compressor forms part of the refrigerant circuit of an air conditioner. A control apparatus of the compressor adjusts the rotation speed of the motor for controlling the amount of compressed refrigerant gas discharged from the compression mechanism, or the displacement of the compressor, per unit time. When the energy efficiency of the motor is lower than a predetermined level, the control apparatus performs on-off control by alternately turning off the motor. During the on-off control, a required amount of refrigerant gas discharged per unit time is obtained, and the energy efficiency of the motor in the on time is higher than the predetermined level.

Abstract: An air-conditioning apparatus having a refrigerant circuit including a condenser, a pressure reducing device, an evaporator, and a variable displacement compressor. The air-conditioning apparatus has a torque detecting device and an external information detecting device. The torque detecting device directly or indirectly detects the reaction torque acting on the compressor, and the external information detecting device detects various external information other than the torque. The air-conditioning apparatus further has a control device for determining a target torque in accordance with the external information provided by the external information detecting device. The control device executes a feedback control program for controlling the displacement of the compressor such that the torque detected by the torque detecting device approaches the target torque.

Abstract: A torque sensor having an improved detection accuracy is disclosed. The torque sensor includes a cylindrical stator. The stator is arranged to face a magnetostrictive member fixed to a shaft. The stator includes a stator body and two retainer rings. When assembling the stator body and the two retainer rings, a pair of exciting coils and a pair of detecting coils are accommodated in the inner wall of the stator. Joints between the stator body and the two retainer rings are not exposed to the inner surface of the stator.

Abstract: A reluctance motor is described in which stator coils are driven with sinusoidal, or substantially sinusoidal, waveforms. Preferably, the spread angle of the stator poles is less that the spread angle of the rotor poles. More preferably, the spread angles of the stator poles &thgr;S and the rotor poles &thgr;r are set such that &thgr;S is approximately equal to 2&pgr;/(m·Nr) and &thgr;r is about (&thgr;S+&pgr;/Nr)/2≦&thgr;r≦(&pgr;/Nr), respectively, wherein Nr is the number rotor poles and m is the number of phases of electric current. By supplying a sinusoidal, or substantially sinusoidal-like, driving waveform to the stator coils, torque becomes relatively constant and does not depend on the angular position of rotation of the rotor. Therefore, torque ripple is effectively decreased.

Abstract: An electric compressor includes a rotary shaft that is driven by an electric motor. The motor generates driving torque. Pistons compress gas in accordance with rotation of the rotary shaft. During one turn of the rotary shaft, the times when the net load torque generated by the pistons is minimum and the times when the driving torque of the motor is minimum occur at substantially the same rotation angles of the rotary shaft. Also, during one turn of the rotary shaft, the times when the net load torque is maximum and the times when the driving torque of the motor is maximum occur at substantially the same rotation angles of the rotary shaft. The driving torque is always greater than the net load torque. Therefore, the motor need not be large to generate sufficient torque.

Abstract: An improved magnetostrictive torque sensor for sensing torque applied to a shaft that is rotatably supported in a housing. A magnetostrictive cylinder is fixed to the shaft. A stator is supported on the shaft by bearings to surround the magnetostrictive cylinder and is accommodated in the housing. The stator incorporates exciting coils and detecting coils such that the coils are located about the shaft. The magnetosttrictive cylinder is strained by torque applied to the shaft. The exciting coils generate flux running through the magnetostrictive cylinder. The generated flux is changed in accordance with the strain of the magnetostrictive cylinder. The detecting coils detect the flux changes. The stator is also rotatably fixed to the housing by bearings. Rotation of the stator relative to the housing is prevented by connectors that couple the stator with the housing. This prevents tension in wires that lead from the stator.

Abstract: An improved torque sensor for detecting the direction and the magnitude of a torque applied to a shaft. The sensor includes a magnetostrictive layer, a pair of bearings, a stator and two nuts. The sleeve is fixed the circumference of the shaft. The layer has a magnetostriction effect in accordance with torque applied to the shaft. A pair of collars are fixed to the shaft at opposite ends of the layer. The bearings are connected to the shaft. Each bearing contacts one of the collars. The stator accommodates two pairs of coils. Each coil pair includes an exciting coil and a detecting coil. The coils surround and face the magnetostrictive layer. The axial position of the stator is determined by the bearings. Each nut is threaded to a threaded portion fixed to the shaft and presses one of the bearings against the corresponding collar. Accordingly, the axial position of the stator is determined.

Abstract: In a non-contacting power supply system for a rail-guided vehicle which can move along a plurality of power supply lines connected to respective power sources and receive a supply of electric power required for moving from the plurality of power supply lines, the rail-guided vehicle comprises a plurality of power receiving cores for receiving a supply of electric power from the plurality of power supply lines. The gaps between the plurality of power supply lines in the portions between the power supply lines are set to be equal to or longer than the length of each of the power receiving cores in the direction of the power supply lines, thereby eliminating the bad influence on the non-contacting power supply system due to the difference between the phases or frequencies of the power sources of the power supply lines.

Abstract: A torque sensor attached to a shaft for detecting torque applied on the shaft is disclosed. The torque sensor of the present invention includes a magnetic portion attached on the shaft and a retainer arranged to surround the magnetic portion and supported to rotate with respect to the magnetic portion. A first coil supported in the retainer to surround the magnetic portion forms a first magnetic circuit passing through the magnetic portion. A power source applies an alternating current to the first coil. A measuring circuit measures torque applied on the shaft based on an alternating current and an alternating current. The alternating current flows in the first coil when the alternating voltage is applied.

Abstract: An apparatus for feeding electric power to a movable body in a non-contact manner. Power lines on which electric power is transmitted are laid on a guide rail. The movable body is powered by the electric power from the power lines. A plurality of pick-up coils are positioned in the movable body for generating induced electromotive force as a drive voltage according to the electric power. The plurality of coils generate different voltages. A motor and a controller are connected to the coils. A motor is driven by a high voltage while the controller is driven by a low voltage.

Abstract: A rail is arranged along a predetermined route of a movable body. The movable body is moved by electric power fed through an electric cable wired along the rail. The rail is constituted by a plurality of rail segments. Each segment includes a body having a predetermined length and a channel-like cross section and an electric cable segment supported by the body extending in the axial direction of the body. The electric cable segment is one of a plurality of segments obtained by dividing the electric cable.

Abstract: A communication system for a plurality of carriages that travel along a rail. A power cable extends along the rail. The cable is used to convey electric current that drives the movable bodies and is also used to carry information between the carriages. The carriages communicate with one another by superimposing communication signals on the current flowing through the cable to transmit information and by extracting communication signals from the current flowing through the cable to receive information. A control unit at a fixed station relays communication signals transmitted between different carriages. The control unit receives communication signals, which the carriages transmit, from the cable, amplifies the signals, and returns the signals to the cable. The recipient carriage receives an amplified communication signal from the cable.

Abstract: An antenna unit for a communication system is disclosed. The communication system includes a rail, a separable power transmission line provided along the rail, carriages running along the rail while receiving power from the power transmission line, and a fixed station for establishing communications with the carriages. Communications between the carriages and the fixed station are accomplished by transmitting a signal via the power transmission line. The antenna unit is detachably located in the path of the power transmission line. The antenna unit includes an antenna device serving as a communication antenna of the fixed station and a conductive line to which the antenna device is attached. A terminal connects each end of the conductive line to an associated separate part of the power transmission line so that the conductive line is located between the separate parts of the power transmission line, thus forming a combined power/signal transmission line.

Abstract: A feeder is disposed along a guide rail that guides an electrically powered vehicle. The electrically powered vehicle has an electric power receiving unit that accommodates the feeder. Electric power is supplied from the feeder to the electrically powered vehicle through the electric power receiving unit on a non-contact basis. The distance between the guide rail and the feeder in a straight portion of the guide rail is different from the distance between the guide rail and the feeder in a curved portion of the guide rail.

Abstract: A non-contact power supply system for supplying electric current from a power supply unit to a carriage that travels along a rail. A pair of cables, which are used to convey electric current that drives the carriage, extend along the rail. Each cable has a first end connected to the first end of the other cable and a second end connected to the power supply unit. A plurality of brackets are located on the rail to support both cables. Each bracket has a pair of hangers projecting horizontally. The hangers each have distal ends for supporting the corresponding cables. A first type of bracket supports the first ends of both cables, and a second type of bracket supports the second ends of both cables. A jumper strap electrically connects the first ends to each other. The jumper strap extends between the distal ends of both hangers and conforms to the shape of a portion of the first bracket that lies in its path. The jumper strap is a thin belt.

Abstract: A system for communication between a fixed station and a carriage, which travels along a rail. The system employs a cable used to supply the carriage with electric power and carries out communication by superimposing communication signals on the electric power flowing through the cable. The communication system includes electric power sources and cables. The cables are each connected to one of the power sources and each cable extends along the rail. A single communication antenna is used by at least two of the cables.

Abstract: A carriage conveying system having a conveyance control device, which outputs communication signals for supplying a carriage with electric power by a feeder cable arranged along a guide rail to move the carriage along the guide rail and for controlling operation of the carriage. A control device transmits the communication signals to the carriage by the feeder cables. The carriage has a driving device for driving the carriage in accordance with the electric power. A controller controls the driving device in accordance with the communication signals. A communicating device receives the communication signals from the feeder cable for conveyance to the controller. The communicating device is located in the vicinity of the feeder cable.

Abstract: A feeder is disposed along a guide rail that guides an electrically powered vehicle. The electrically powered vehicle has an electric power receiving unit that surrounds the feeder on a non-contact basis. Electric power is supplied from the feeder to the electrically powered vehicle through electric power receiving units. The number of electric power receiving units is two. Each of the electric power receiving units has a mechanism that causes the electric power receiving unit to be inclined in the tangent direction of the feeder at a curved portion of the guide rail in such a manner that the distance between the feeder and the electric power receiving unit is kept so that optimum power can be obtained.