Matsushita Electric Industrial Co., Ltd.

Yoshihiro Ikemoto

Teruo Maruyama

Yoshikazu Abe

Akira Takara

Jiro Kataoka

Yoshinori Furusawa

Tohru Nakagawa

Toshinori Otsuki

Takuji Nakamura

Tutomu Hamada

Isao Tashiro

Takeshi Nagasawa

Katsuhiko Asai

Takafumi Asada

Keishi Kubo

Takeshi Masaki

Masahiro Muro

Toru Nakagawa

Hiroyuki Funasho

Toshikazu Shogase

Koji Nakagawa

Tatsuo Itou

Isamu Hashimoto

Toshifumi Miyake

Koji Fujimoto

An evacuating apparatus includes a first pump section disposed on a suction opening side, a second pump section for exhausting a smaller amount of gas than the first pump section, the second pump being disposed in an exhaust opening side, a plurality of rotors accommodated in a housing, bearings for supporting rotation of the rotors, a suction opening for drawing fluid and a first exhaust opening thereof both formed on the housing, and a plurality of motors for driving the rotors. In the apparatus, the first pump section is a pump of positive displacement type formed by utilizing a volume change of a space defined by the rotors and the housing, and the second pump section is a viscous-type pump formed by utilizing a relatively moving surface formed in a small gap defined between the rotors and the housing.

Evacuating apparatus having interengaging rotors with threads having a

A radial electromagnetic attraction stator of a magnetic bearing system is manufactured by forming laminated core pieces as divisions of a laminated core each having a unit number of pole teeth, winding wires around pole piece portions of the laminated core pieces with insulators interposed, assembling a predetermined number of the laminated core pieces wound with the wires and fixing joined portions of the laminated core pieces. This manufacturing method prevents spaces in which the wires are wound from being limited by adjacent pole teeth unlike the conventional integral laminated core, permits winding the wires in a maximum number of turns in open spaces and allows to obtain the radial electromagnetic attraction stator having a high space factor, thereby being capable of providing a magnetic bearing system having a high load capacity and usable as a bearing capable of enhancing performance of production appliances such as working appliance and vacuum pumps.

Manufacturing method for magnetic bearing system

A positive displacement vacuum pump, in which a plurality of rotors are driven into synchronous operation by independent motors, uses a rotational position sensor making use of the electromagnetic induction effect for obtaining rotational position information for the individual shafts. The rotational position sensor is cooled.

Vacuum pump having lubrication and cooling systems

A vacuum pump includes a plurality of rotors of different outer diameters accommodated in a housing so that a fluid transportation space is defined by the housing and the plural rotors. Rotary shafts are integrally formed with the respective rotors and a first motor, which is a high frequency motor, for driving the rotary shaft of the smaller diameter rotor as a driving shaft. A second motor, which is an AC servo motor or pulse motor, is provided for driving the other rotary shaft as a driven shaft. A rotation detecting device is provided adjacent each shaft for detecting rotating angles and/or rotating speeds of the first and second motors. Also provided is a fluid suction port and a fluid discharge port which are formed in the housing, and a control device for controlling rotation of the driven shaft based on data from the rotation detecting device so as to synchronize the rotation of the driven shaft driven by the second motor with that of the driving shaft driven by the first motor.

Vacuum pump having different diameter rotors and a drive motor

With a device for reciprocating a cutting tool in small steps, the cutting tool is reciprocated in small steps in such a way that a feed mark (track of the cutting tool on the workpiece) is inverted each time the workpiece makes a round, by which the chip is varied in width and cut at a track crossing portion during the machining. Thus, chips are broken into short pieces so that the cutting efficiency and the cutting quality are improved and that the chip disposal is facilitated. Moreover, a safe turning process can be achieved.

Chip-broken turning method and apparatus

A second circuit B which is composed of a band-pass filter circuit (5) which takes out a rotating body position signal input from a sensor (1) while scarcely varying a phase within a range including a normal rotation frequency and a reverse rotation frequency of a rotating body, a gain circuit (6) for controlling a gain of an output signal from the bandpass filter circuit (5) and a second notch filter circuit (7) for attenuating components having frequencies lower than the natural frequency of an output signal from a gain circuit (6) is disposed separately from a main circuit A, and an output signal from the second notch filter circuit (7) is positively fed back to the main circuit A through an adding circuit (8). This composition makes it possible to obtain a magnetic bearing which is capable of sufficiently attenuating a bending natural frequency of a high-speed rotating body and supporting this rotating body with high rigidity even when a normal rotation frequency and a reverse rotation frequency of the high-speed rotating body vary.

Magnetic bearing controller

A processing apparatus with a movable processing tool, which includes a position detecting sensor for detecting a rotary position of a to-be-processed object held by a holding member set to a rotary main shaft, a deflection detecting sensor for detecting an amount of rotational deflection of a processing reference surface of the object, a waveform shaping device for shaping an output signal from the deflection detecting sensor into a waveform approximate to a sine curve, an operational device for operating a positional correction amount for a processing tool at a processing point of the object on a basis of an output signal of the waveform shaping device synchronously with rotation of the rotary main shaft, an output device for outputting the positional correction amount for every rotary position and every processing point based on an output signal from the operational device, a fine adjustment mechanism for minutely driving the processing tool based on an output signal from the output device, and an NC table moving in two dimensions the fine adjustment mechanism to process the object by the processing tool.

Processing apparatus with movable processing tool and processing method

Evacuating apparatus

In an electric discharge machine and machining method for processing an object through electric discharge by impressing a voltage between a processing electrode and the object, the processing electrode and object are relatively vibrated by a vibrating part using a piezoelectric element while a gap between the processing electrode and object is properly retained at all times. The electric discharge is accelerated when the gap is small, whereas the insulated state is maintained when the gap is large. This kind of condition is stably produced in accordance with a frequency of the vibration. If the frequency is set in the range of 50-500 Hz, a shortcircuit or an arc state is less likely to occur. The vibration is effective to quickly discharge processing debris at the discharging gap.

Electric discharge machine with electrode or object vibration and

A fluid feed apparatus includes a suction hole and a discharge hole for a fluid, a fluid transfer part provided between a rotor and a stationary member containing the rotor, a shaft coupled with the rotor, a rotation actuator for rendering a relative rotating motion between the shaft and the stationary member in a surface perpendicular to an axis of the shaft, a driving power supply for the rotation actuator, a rotating motion control unit for the rotation actuator, a swing actuator for rendering a relative swinging motion between the shaft and the stationary member, a driving power supply for the swing actuator, and a swinging motion control unit for the swing actuator. Synchronous control is performed by the rotating motion control unit and the swinging motion control unit so that the rotating motion and the swinging motion are synthesized to implement a revolving motion.

Fluid feed apparatus and method

A processing apparatus with a movable processing tool, includes a deflection detecting device, a rotating position detecting sensor, an arithmetic unit, an output circuit, a fine adjustment device, and an XY table. The detecting device detects a plurality of deflection amounts of a processing reference surface of a to-be-processed work held by a work holding member mounted to a main shaft of an NC processing apparatus. The sensor detects a rotating position of the work. The unit calculates a correcting amount of the tool at a processing point of the work from a measured value of the sensor and plural measured values of the deflection amounts of the detecting device. The circuit outputs the correcting amount synchronously with the rotating position and processing point of the work. The adjustment device has the tool fixed thereto for finely moving the tool in a processing direction based on an output from the circuit. The fine adjustment device is secured to the XY table.

Processing apparatus with movable processing tool

A fluid rotating apparatus includes non-circular rotors accommodated in a housing, rotary shafts having the rotors, bearings for rotatably supporting the shafts, a fluid suction and a fluid discharge ports formed in the housing, a positive displacement pump section formed of combination of the housing and rotors, and gears connected with the shafts having backlash set smaller than backlash between the rotors. The apparatus includes motors for independently driving the shafts, a device for detecting a rotating angle or speed of rotation of the motors, a unit for controlling the motors to synchronously rotate, a unit for detecting a current running in the motors, a unit for detecting a relative position of the shafts, and a rotation commanding unit, to which outputs from the motor current detecting unit and relative position detecting unit are inputted, for deciding whether or not a shift amount of the synchronous rotation is larger than a specified value based on the outputs of the motor current detecting unit and/or the relative position detecting unit, and outputting to the motor controlling unit a signal to decelerate one shaft when the rotation command unit decides that the shift amount of the synchronous rotation is larger than the value.

Fluid rotating apparatus with plural drive motor synchronization system

A fluid-rotating apparatus comprises a positive displacement pump structure section for rotating the rotary shaft of each of a plurality of rotors synchronously. In controlling the synchronous rotation of the rotary shafts by a PLL control method, a gain-switching means device is provided to set a high gain in a PLL control circuit when the rotary shafts are accelerating or decelerating and setting a low gain therein when the rotary shafts are rotating in a steady state.

Fluid-rotating apparatus

A method for detecting a minute displacement of a probe includes an emission from a light source of two light beams having different polarizing directions. The light beams are subsequently diverged by a first lens so as to pass through a beam splitter towards a separating prism. The light beams having passed through the prism are separated into first and second measuring beams which are subsequently focused by a second lens on first and second, spaced reflecting surfaces. The first and second measuring beams are then reflected by the first and second reflecting surfaces, respectively, so as to enter respective photodetectors after having passed through the separating prism, the beam splitter and a polarizing beam splitter for passing therethrough the first and second measuring beams or reflecting them depending on the polarizing direction of the incoming light. The first and second photodetectors outputs respective signals indicative of the associated positions of foci which are then processed by a signal processing circuit to provide an indication of the minute displacement of the probe.

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Katano, Japan

Yoshihiro Ikemoto