Zexel Gmbh

Diesel Kiki Co., Ltd.

Seiko Epson Corporation

Epson Corporation

Tama Manufacturing Co., Ltd.

Nobukazu Takagi

Nobuyuki Nakajima

Yukio Kazahaya

Masakuni Ishikawa

Seiji Kuchiki

Kiyohiro Harada

Osamu Shinkawa

Takeshi Seto

Akihito Uetake

Susumu Saito

Tatsuya Shimoda

Osamu Takahashi

Kenichi Endo

Masataka Ishikawa

Yoriyuki Takekawa

Tatsuhiko Abe

Takeshi Fujihisa

Sakae Mashio

Norikatsu Kiso

Yamaha Yoshikazu

A motor driving apparatus PWM-controls a DC voltage from a rectifying unit according to a rotation speed setting information, and drives a motor by voltage pulse chooped by PWM. The rectifying unit is controlled so that a full-wave rectification is performed when the motor runs at a rotation speed below a prescribed rotation speed and a voltage-doubler rectification is performed when the motor runs at a rotation speed above the prescribed rotation speed. On the other hand, in case a motor drives a compressor of an air-conditioning system, the rectifying unit is controlled so that the full-wave rectification is performed when the air-conditioning system is a cooling operation and the voltage-doubler rectification is performed when the air-conditioning system is a heating operation. When the rectifying unit is controlled for the full-wave rectification, even if a width of voltage pulse given to the motor is decreased, a voltage value of the voltage pulse is half as compared with the voltage-doubler rectification. Hence, since a motor current is small and its current variation is also small, a hysteresis loop due to a variation in magnetic flux becomes small and an iron loss is reduced. When the rectifying unit is controlled for the voltage-doubler rectification, since a DC voltage which is the double of that of the full-wave rictification is supplied, the motor capacity can be increased.

Motor driving apparatus for pulse-width modulation controlling a DC

In a scroll type compressor, a simple structure provides oil intake assistance to ensure that lubricating oil in an oil space is induced into a spiral groove in correspondence to the rotation rate of a drive shaft. The drive shaft is provided with an inclined spiral groove which is formed in the external circumferential surface of the drive shaft. The drive shaft slides in contact with a main bearing. A leading end of the spiral groove, in the direction of the rotation of the drive shaft, communicates with the oil space and a trailing end of the spiral groove opens into the lubricating oil reservoir. The lubricating oil is supplied to the area where the drive shaft slides in contact with the main bearing by the spiral groove. Also, upon rotation of the drive shaft, intake of lubricating oil into the spiral groove is assisted when the suction force is reduced due to a high rotation rate.

Scroll type compressor

A scroll type compressor including a drive shaft which is provided with a spiral groove formed in an external circumferential surface of the drive shaft. The spiral groove communicates diagonally between the oil space and the upper portion of the main bearing to ensure sufficient lubrication and sealing in the area where the drive shaft slide in contact with the main bearing. A seal bearing portion is positioned between the oil space and the low pressure space to isolate the oil space from the low pressure orbiting space, achieving an improvement in lubrication. The seal bearing portion is constituted with a seal washer, a seal bearing and a seal member, and, furthermore, with seal reinforcing material, to especially improve the seal between the oil space and the oscillation space.

Scroll type compressor having a seal bearing unit

A compressor start-up controller includes a compressing section (37-39) for compressing a refrigerant; a motor (25) connected to the compressing section for rotating the compressing section; a drive circuit (10) connected to the motor for driving the motor; a rotation detecting device (1) connected to the drive circuit for detecting whether the motor is normally rotating; a control unit (8) connected to the drive circuit for operating the motor in a step mode at a very slow rotation at its start-up for effecting electricity conducting control to gradually increase or decrease commutating current at a very slow speed during the step mode operation at the motor start-up.

Compressor start-up controller

In order to provide a simple structure to achieve sufficient lubrication and sealing in the various areas of a scroll compressor where sliding contact occurs, a spiral groove that communicates between a high-pressure side space and an area at an upper portion of a main bearing is formed on the external circumferential surface of the drive shaft where it comes in contact with and slides against the main bearing. A seal bearing is provided in a drive shaft-receiving block between the high-pressure side space and a low pressure side space to seal off the high-pressure side space from the low pressure side space. An oil supply hole is provided that communicates between the high-pressure side space and an oscillation space which is formed by an oscillating scroll member and an oscillating shaft. With this, a first oil passage that lubricates the main bearing and a second oil passage that lubricates an oscillating shaft-insertion hole are formed. A seal washer, the surface of which is polished to a specific roughness, is provided between the seal bearing and the drive shaft and, in addition, an elastic member is provided between the seal bearing and the block.

Scroll type compressor having an oil seal bearing for the drive shaft

The compressor activation control unit a rotation detecting means for detecting whether or not the motor is normally activated when the compressor is activated, a judging means for judging that the compressor interior is filled with a liquid refrigerant when the motor is not judged to be in the normal activating condition by the rotation detecting means, and a control means for step-driving the motor at a very slow-speed no more then one rotation per second through the driving circuit when the motor interior is judged to have been filled with the liquid refrigerant by the judging means.

Control unit for activating compressor

Here is disclosed a scroll-type fluid handling machine having a hermetically sealed casing enclosing therein a stationary side scroll member fixed to the casing, a movable side scroll member adapted to be rotatable in engagement with the stationary side scroll member and an electromotor used to drive the movable side scroll member, wherein said electromotor comprises a linear motor consisting of movable side magnets and stationary side coils mutually facing in the axial direction of the machine itself and is adapted to directly drive the movable side scroll member. Such feature makes the drive shaft as well as the crankshaft which have conventionally been essential to the machine unnecessary, thereby minimizing a mechanical loss and improving a mechanical efficiency. In addition, the axial dimension of the machine can be substantially reduced so as to obtain a compact, light weight machine.

Scroll-type fluid handling machine

Here is disclosed an air conditioner comprising a scroll type compressor and a brushless DC motor having a rotor provided with a permanent magnet and a stator provided with a sensor adapted to detect a relative position of said rotor and said stator. Here is additionally disclosed an air conditioner in which the rotor of the brushless DC motor comprises a permanent magnet basically made of rare earth elements inclusive of yttrium, transition metal and boron and a driving circuit for the motor includes a braking circuit adapted to excite coils of the motor to thereby reduce reverse rotation of the rotor.

Scroll compressor with reverse rotation speed limiter

In a fuel injection system having a distribution-type fuel injection pump, fuel is supplied successively to cylinders of an engine from a pressurizing chamber of the pump. The pressurizing chamber communicates with a low-pressure chamber through a relief passageway opened and closed by an electromagnetic valve. During a stroke in which volume of the pressurizing chamber is reduced by each forward stroke of a plunger, opening and closing of the valve are controlled, to control starting timing and/or termination timing of fuel injection to the cylinders. A delay occurs in the starting timing and/or the termination timing with respect to drive pulses supplied to the valve, due to an operation delay of the valve. A plurality of memory sections are provided for storing therein delay times for the respective cylinders. A starting point or a termination point of the drive pulse is advanced correspondingly to the delay times stored respectively in the memory sections, at fuel injections with respect to the respective cylinders.

Distribution-type fuel injection system controlled by electromagnetic

A fuel injection device for internal combustion engines is disclosed, wherein the fuel injection quantity for each fuel injection is determined by deducting an amount of fuel which corresponds to the amount of piston overshooting detected when a booster piston forces fuel at the preceding fuel injection. The fuel injection thus determined is substantially equal to the desired fuel injection quantity.

Fuel injection device

In a solenoid valve with ON/OFF switch arranged by a valve member and the associated valve seat defined in an electrically conductive body, the solenoid valve has a stopper connected to the valve member for setting the stroke of the valve member and comes in contact with the body when an actuator for driving the valve member is in its de-energized state and an electrically insulating sheet provided between the stopper and the body so as to prevent the valve member for coming in contact with the body through the stopper.

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Konan, Japan

Nobukazu Takagi