Abstract: A gas compressor has a cylinder chamber provided with discharge holes. Openings are in communication with the discharge holes, respectively. Discharge passages having the same length are connected with the openings, respectively. The ends of the discharge passages are connected with a common passage. During operation of the cylinder chamber, discharge valves cause the expelled gas to produce pulsations on the upstream side of the two openings. The pulsations are shifted in phase by a half wavelength. Noise due to the pulsations is reduced, because the pulsations of the expelled gas cancel out each other when the gas flows through the common passage.

Abstract: A motor armature which allows assembly works to be facilitated and which can be miniaturized and thinned is provided. An inner cylinder 1 and an outer cylinder 2 are disposed coaxially and a plurality of pole pieces 3 are provided radially at equal intervals between the inner cylinder 1 and the outer cylinder 2. The inner cylinder 1 is formed into a cylindrical shape by curling up in the longitudinal direction a hoop member (band steel) made of a magnetic material and having a predetermined thickness and length. The outer cylinder 2 is made of the hoop member similarly to the inner cylinder 1. The pole piece 3 is what a coil 4 is wound around a wire piece 5 obtained by cutting a wire (wire rod) made of a magnetic material and having a predetermined thickness into a predetermined length. One end of the wire piece 5 is fixed to the outer peripheral face of the inner cylinder 1 by means of welding or the like and the other end of the wire piece is fixed to the inner peripheral face of the outer cylinder 2.

Abstract: There is provided an idling engine speed control apparatus which can economically and suitably control an idling engine speed in the case where a variable displacement type compressor with a variable displacement is mounted is a part of an automotive air conditioning system. A the time of idling, a duty ratio of a control valve current value sent as an external signal to a control valve is sent also to an engine controller, and the engine control apparatus controls the output of an engine on the basis of the duty ratio. For example, when the duty ratio becomes high from a small value, since the present operating state of the compressor is in the direction where the differential pressure becomes high and the displacement is increased, it is expected that a large load is applied to the engine. Thus, in this case, the engine output is controlled correspondingly to a large duty ratio and the idling engine speed is made high.

Abstract: An interacting term existing in a control system is decoupled on the basis of a regular condition of a decoupling matrix. Then, an hyperplane &sgr; which has been obtained to satisfy the Lyapunov stability condition is designed. A control quantity is converged along the hyperplane &sgr;. In this case, even if the uncertainty is generated in a C matrix for connecting a state variable x(t) and an output y(t) of an object to be controlled, it is possible to converge the control quantity while always satisfying the Lyapunov stability condition. A non-linear input gain ki (x,t) used in the control system is designed to be greater than a predetermined value when there is no uncertainty in the C matrix to satisfy the Lyapunov stability condition. Also, a control input signal based upon the sliding mode decoupling control is converted to an articulation torque by a Jacobian. Also, for the control input signal, reverse dynamics of non-linear force are added thereto.

Abstract: To provide a reciprocation motor capable to detect rotation angle of rotor accurately. Rotor 1 is a magnet having two poles to radial direction and comprises half-cylindrical magnets. Driving coils 5a and 5b are bound equally at coil board 3. Magnetic sensor 7 is fixed at outside and under side of driving coil 5b on coil board 3. Such a construction makes magnetic sensor hard to be influenced by flux generating caused by current flowing through driving coil 5b. Therefore, it is possible to improve position detecting accuracy of rotor 1.

Abstract: A spindle apparatus comprises a rotary body and at least a pair of magnetic bearings for levitating the rotary body by magnetic forces. A combined motor and magnetic bearing device is disposed between the magnetic bearings for imparting a rotational torque to the rotary body and for positionally controlling the rotary body by magnetic forces. A control circuit outputs and exciting current to the magnetic bearings and the combined motor and magnetic bearing device and for makes an adjustment of the exciting current of the magnetic bearing and the combined motor and magnetic bearing device to hold the rotary body afloat in a predetermined position.

Abstract: A communication abnormality detecting/coping device and a vacuum pump remote monitor control device are provided, which are capable of detecting the presence/absence of an abnormality in data communication and reducing an influence of the abnormality on a system device when detecting the abnormality. An operation acknowledge message 51 is transmitted to a system device (30) from a turbo-molecular pump control device (20) in Step 1. A reply message (53) indicative of the reception of the operation acknowledgement message 51 by the system device (30) is transmitted to the turbo-molecular pump control device (20) in Step 3. In Step 5, an elapsed period of from a time at which the operation acknowledgement message (51) is transmitted to a time at which a reply message (53) is received is measured, and if the elapsed period exceeds the preset period, the abnormality in the communication system is warned in Step 6.

Abstract: A turbomolecular pump device having a DC brushless motor provided with a simplified rpm detection mechanism is provided. A pickup coil for detecting a magnetic flux produced by a permanent magnet of the DC brushless motor is built in the motor. Namely, a small size, low cost, simple and strong pickup coil is disposed in a space between the permanent magnet (rotor) of the DC brushless motor and the motor drive coil (stator coil). The magnetic flux produced by the permanent magnet in the pickup coil is detected. This is converted into an rpm signal of the DC brushless motor by a sequence controlling circuit. It is supervised whether or not the overspeed is performed. Then, when the overspeed is detected, an interruption command is fed to the power source breaker so that the supply of the power is forcibly interrupted to thereby stop the DC brushless motor.

Abstract: A motor armature having a simplified assembly comprises an inner cylinder and an outer cylinder arranged coaxially, and a plurality of pole pieces provided radially at equal intervals between the inner and outer cylinders. The inner cylinder is formed into a cylindrical shape by curling up in the longitudinal direction a first hoop member (band steel) formed of a magnetic material and having a predetermined thickness and length. The outer cylinder is formed of a second hoop member similar to the first hoop member. The pole pieces each comprise a wire piece cut from a wire formed of a magnetic material and having a coil would thereon. One end of each pole piece is welded to one of the hoop members and the other end of the pole pieces is welded to the other hoop member.

Abstract: To keep a temperature of an interior of an automotive vehicle at least at a level of an external atmospheric temperature even if the vehicle is parked with an engine being stopped for a long time, an automotive air-conditioning apparatus is composed of a cooling device 12 to be controlled by a controller 13, a pre-cooling device 20 for pre-cooling the interior of the vehicle, and a sub-controller 18 for controlling the pre-cooling device. The pre-cooling device is composed of a cooling thermoelectric element module 22, a ventilation fan 23, a solar battery 21 and a pre-cooling storage battery 24 charged by the solar battery.

Abstract: A temperature adjusting device has an air-tight container. A thermoelectric element is disposed in the air-tight container and has first and second opposite surfaces each capable of radiating and absorbing heat through a Peltier effect. A first heat exchanger is disposed in the air-tight container for performing heat exchange between a thermally conductive first medium and the first surface of the thermoelectric element. A tank is disposed in the air-tight container and is connected to an inlet side of the first heat exchanger for storing the first medium. A second heat exchanger is disposed in the air-tight container for performing heat exchange between a thermally conductive second medium and the second surface of the thermoelectric element. A pump circulates the first medium through the first heat exchanger. A temperature sensor detects a temperature of the first medium circulated by the pump.

Abstract: A ferrule for use in an optical fiber connector comprises a main body having an insertion hole for receiving an optical fiber element. The insertion hole has a first end for receiving the optical fiber element, a second end, a positioning portion disposed proximate the second end for connection to an outer peripheral surface of the optical fiber element to position the optical fiber element in the insertion hole, and a divergent portion diverging smoothly from the positioning portion to the first end.

Abstract: A dynamic pressure bearing device comprises a rotary member mounted for rotation, and a dynamic pressure bearing rotatably supporting the rotary member. The dynamic pressure bearing has a stationary portion and a disk integrally connected to the stationary portion. The disk has surface portions defining thrust dynamic pressure bearing portions for supporting the rotary member in an axial direction and a radial dynamic pressure bearing portion for supporting the rotary member in a radial direction. A gap is disposed between the dynamic pressure bearing and the rotary member for receiving oil. A space is provided in fluid communication with the gap. The space has a central portion slanted downwardly in the radial direction for preventing leakage of the oil and has a diameter increasing gradually from the central portion in the radial direction.

Abstract: An automatic blade changing system of a dicing machine uses a blade which is fixed to an auxiliary stopper member provided with a thread which is engaged with a thread of a spindle. The automatic blade changing system consists of two blade holding means which hold the blade to which the stopper member is fixed and rotate the blade relatively to the spindle in the state wherein the blade is forced to the spindle, a blade accommodating means which accommodates a blade to replace the blade, a moving means for moving the blade holding means between the end of the spindle and the blade accommodating means.

Abstract: To prevent the problem of dragging on an auxiliary bearing which tends to occur in a motor in the vicinity of a resonance point of rigid mode during the start-up of a three axis control magnetic bearing apparatus, a radial position correcting electromagnet is provided. The radial position correcting electromagnet has a magnetic pole extending in the direction of a radius of a metal disc of the motor through which the motor shaft passes. A voltage having a short period is applied to the radial position correcting electromagnet at a plurality of times in the vicinity of the resonance point of rigid mode upon start-up of the motor to attract the metal disc and thereby adjust the radial position of the shaft to prevent excessive contact between the shaft and other parts of the three axis control magnetic bearing apparatus.

Abstract: A swiveling table apparatus comprises a base and a table main body disposed on the base and mounted for swiveling movement about a swivel axis. A driving mechanism includes a servo motor for generating a driving power to swivel the table main body about the swivel axis. A power transmission mechanism transmits the driving power of the servo motor to the table main body.

Abstract: A positioning system comprises a feeding mechanism having three or more feeding units disposed in a moving direction of a moving body. Each of the feeding units has first and second moving elements for clamping and unclamping the moving body, feeding the moving body in the moving direction from an initial position to a target position, and returning the moving body to the initial position. A memory device stores preselected phase and amplitude values of the first and second moving elements. A calculating device calculates phase and amplitude command values for the first and second moving elements based on the phase and amplitude values stored in the memory device. An output device outputs driving command values to the first and second moving elements based on the calculation result of the calculating device. A control device controls the feeding units to clamp the moving body by all of the feeding units after the moving body has been moved to the target position.

Abstract: A table feeder apparatus comprises a base, a feed screw rotatably supported on the base and a motor for rotating the feed screw about a feed axis. A feed nut is mounted on the feed screw and a block is mounted integrally with the feed nut. A table is disposed on the block for movement along the feed axis. In one aspect, a slide mechanism is disposed between the block and the table. The slide mechanism is slidable in at least one of a horizontal direction and a vertical direction transverse to the feed axis. During movement of the table, the slide mechanism slides to absorb a force applied to the feed nut, tending to displace the block and table in a direction transverse to the feed axis, to prevent the applied force from being transmitted to the table. In another aspect, the table is provided with an opening in which a table portion is removably fitted. Removal of the table portion facilitates maintenance of the slide mechanism without requiring the entire table feeder structure to be dismantled.

Abstract: A grinding machine comprises a grinding member having a thickness greater than 10 mm and an outer contact surface extending in a thickness direction of the grinding member for contacting a surface of a workpiece. The grinding member is supported by a first rotational shaft for rotation about a first rotational axis. A first moving mechanism reciprocates the first rotational shaft along a first displacement axis. The workpiece is supported by a second rotational shaft for rotation about a second rotational axis perpendicular to the first displacement axis and the first rotational axis. A second moving mechanism moves at least one of the workpiece and the grinding member along a second displacement axis to bring the outer contact surface of the grinding member into linear contact with the surface of the workpiece to grind the workpiece. The linear contact between the outer contact surface of the grinding member and the surface of the workpiece has a contact length greater than 10 mm.

Abstract: To provide magnetic bearing devices capable of preventing undesirable consequences caused by conical mode or parallel mode resonance which is liable to occur during acceleration of a rotor. A band-pass filter 24 is connected in series with a PID control circuit 12 is for improving stiffness in a specific frequency band. A displacement of a rotor 2 detected by a displacement detector 30 is entered to a switcher 32. On the other hand, a rotational speed sensor 7 detects the revolving speed, and a compensator switching discriminator 26 causes a switch 32s of the switcher 32 to connect to an output terminal 32b or to an output terminal 32c when the revolving speed coincides with preset revolving speed data. The preset revolving speed data defines specific revolving speeds occurring below and above a frequency band which includes a first conical mode resonant frequency and a second conical mode resonant frequency.