Ebara Corporation

Shunichi Aiyoshizawa

Kazuyuki Kasahara

Daisuke Konno

Kazuto Hirokawa

Yoshio Sato

Sachihiko Miwa

Yoichi Kanemitsu

Yumiko Noda

Manabu Toshimitsu

Hiroyuki Shinozaki

Nobuharu Noji

Mamoru Suzuki

Toshiharu Nakazawa

Yu Ishii

Shinichi Sekiguchi

Tadashi Kataoka

Toshimitsu Barada

Ryuichi Kosuge

Yuji Shirao

Ryo Kato

Junya Kawabata

Yasushi Hisabe

Atsushi Ooyama

Toshihiro Ohtani

Masahiko Kishi

Takashi Kataoka

Toshiya Kanamori

Yoshikazu Suganuma

Tohru Maruyama

Yoshiyuki Maruta

Noriyuki Osada

Hideo Tsuboi

Shunsuke Mimura

Tatsuo Hinata

Setsuji Shinoda

Chikara Makino

A submersible motor pump includes a water jacket having a circulation passage of a coolant, a centrifugal impeller for circulating the coolant, a suction passage configured to provide fluid communication between the circulation passage and a fluid inlet of the centrifugal impeller, and a discharge passage configured to provide fluid communication between a fluid outlet of the centrifugal impeller and the circulation passage. The discharge passage includes a heat-exchange passage formed by two wall surfaces, one of which is constituted by a member which contacts a liquid conveyed by a main impeller. The heat-exchange passage has a circular shape extending radially outwardly from the fluid outlet of the centrifugal impeller. The heat-exchange passage includes at least one axial passage section having a length component in an axial direction of the rotational shaft.

Submersible motor pump, motor pump, and tandem mechanical seal

The present invention provides an apparatus for heating or cooling a polishing surface. This apparatus includes a heat exchanger arranged so as to face the polishing surface when the workpiece is polished. The heat exchanger includes a medium passage through which a heat-exchanging medium flows, and a bottom surface facing the polishing surface. At least a part of the bottom surface is inclined with an upward gradient above the polishing surface such that a polishing liquid on the polishing surface generates a lift exerted on the bottom surface during movement of the polishing surface.

Apparatus for heating or cooling a polishing surface of a polishing apparatus

The present apparatus includes a casing () having a gas introduction opening () for introducing a gas into the casing and a gas discharge opening () for discharging the gas from the casing, a gas circulating tube passage () communicating with the casing for effecting circulation of the gas, a circulating fan () for effecting circulation of the gas in the casing through the gas circulating tube passage, and a valve () switchable between a position for conducting the introducing and discharging of the gas into and from the casing through the gas introduction opening and the gas discharge opening and a position for effecting circulation of the gas in the casing through the gas circulating tube passage. The apparatus further includes a trap (), a filter () and a heat exchanger () for conducting a desired treatment with respect to the circulated gas, such as removal of particles.

Method and apparatus for forming required gas atmosphere

A magnetic bearing enables to rotatably support a levitated body non-contactingly disposed in a hermetically sealed container filled with a gaseous process substance of a corrosive nature, while without contaminating the gaseous environment and suffering from corrosion. The magnetic bearing has an electromagnet for supporting a levitated body, a displacement sensor for detecting a levitated position of the levitated body, and a controller for supplying signals and excitation currents to the displacement sensor and the electromagnet through cables. An electromagnet target of the magnetic bearing that generates variations in magnetic fields due to rotation of the levitated body, is constructed of a single piece of ferromagnetic material, and is provided with an electrical insulation structure oriented parallel to magnetic fluxes generated by the electromagnet.

Magnetic bearing and circulation fan apparatus

A drum motor for a VCR includes radial and thrust hydrodynamic bearings that are composed of a rotor-side bearing member formed by bringing a pair of first and second thrust plates into direct contact with both end surfaces of a radial bearing element and integrating them into one unit, and a stator-side bearing member in the form of a radial sleeve the inner peripheral surface and both end surfaces of which respectively cooperate with the outer peripheral surface of the radial bearing element and the mutually facing surfaces of the first and second thrust plates. A rotor magnet is secured to a rotating shaft. A motor casing is secured to the outer peripheral surface of the radial sleeve. A stator unit is secured to the motor casing. A dynamic pressure generating groove is provided on either each end surface of the radial sleeve or each of the mutually facing surfaces of the first and second thrust plates. The run-out of a rotor-side unit in both the thrust and radial directions is made extremely small and the change in the relative height of the rotor-side unit in the thrust direction due to a change of the position of the motor in which it is used is minimized.

Drum motor for VCR

A spindle motor with an H-type pneumatic dynamic bearing has a high durability against repeated starts and stops of rotation. The H-type bearing is composed of a radial bearing member, thrust plates firmly fixed to opposite ends of the radial bearing member and a cylindrical radial sleeve, which form a radial pneumatic dynamic bearing and thrust pneumatic dynamic bearings. A stator core is fixedly secured around a rotary member, which is in turn fixedly secured around the cylindrical radial sleeve. A total thrust clearance a+a' of the thrust bearings is represented by an inequality of (a+a')/A&lt; 2.5/10.sup.4 based on a sliding surface diameter A of each thrust plate, a and total radial clearance b+b' of the radial bearing is represented by an inequality of (b+b')/B&lt;5/10.sup.4 based on a sliding surface diameter B of the radial bearing member.

Spindle motor using dynamic pressure bearings

A dynamic pressure bearing is provided with a moving side bearing member and a fixed side bearing member so as to support a rotor for rotation by generating a fluid dynamic pressure between the moving side bearing member and the fixed side bearing member. The dynamic pressure bearing includes a high-frequency exciting device for applying a high-frequency vibration to the fixed side bearing member at the time of at least one of start-up and shutdown of the rotor. In this way, both bearing members are kept almost free from contact with each other and a frictional resistance at start-up and/or shutdown is minimized.

Dynamic pressure bearing

A spindle motor has a rotor supported by a stator through a thrust bearing and a radial bearing. At least the thrust bearing is a hydrodynamic bearing. The spindle motor is provided with a device for adjusting the thrust laod that is applied to the thrust bearing. The load adjusting device has an electromagnet that is provided on the stator and a permanent magnet that is provided on the rotor in opposing relation to the electromagnet. Either the repelling force or the attraction force, which acts between the electromagnet and the permanent magnet, is controlled by changing the current supplied to the electromagnet.

Spindle motor

A bearing structure suitable for a spindle motor or the like, which enables such a motor to rotate with minimal vibrations. The bearing structure comprises a stator including a support shaft which is disposed on a base, and a rotor which is rotatably disposed around the support shaft. A radial hydrodynamic bearing and a thrust hydrodynamic bearing are disposed between the stator and the rotor. The stator has the support shaft, a thrust plate and a radial cylindrical member which is concentric with the support shaft. The thrust plate is secured to an end surface of the radial cylindrical member. The support shaft extends through the centers of the radial cylindrical member and the thrust plate. The rotor has a radial sleeve. The radial hydrodynamic bearing is formed from the inner peripheral surface of the radial sleeve and the outer peripheral surface of the radial cylindrical member, which face each other and either of which is formed with herringbone-shaped grooves for generating dynamic pressure. The thrust hydrodynamic bearing is formed from an end surface of the radial sleeve and a sliding surface of the thrust plate, which face each other and either of which is formed with spiral grooves for generating dynamic pressure. A rolling bearing may be added in order to minimize the starting torque in the bearing structure.

Bearing structure

A spindle motor which is designed to rotate with minimal vibrations and hence is suitable for a hard disk driver. The spindle motor employs hydrodynamic bearings as radial and thrust bearings. A support shaft is formed in a cylindrical configuration with a center hole, and a rotor has a columnar portion which is inserted into the center hole in the support shaft. A thrust bearing collar is attached to the lower end of the rotor, and a thrust bearing member is secured to a base in opposing relation to the thrust bearing collar. A group of stator coils and a radial bearing member are disposed on either the inner peripheral surface of the center hole in the support shaft or the outer peripheral surface of the support shaft, and a group of rotor magnets and a radial bearing sleeve are disposed on either the outer peripheral surface of the columnar portion or the inner peripheral surface of the rotor in opposing relation to the stator coil group and the radial bearing member.

A spindle motor comprising a stator including a support shaft positioned on a base, a cap-shaped rotor rotatably and concentrically disposed around the support shaft, thrust and radial bearings disposed between the stator and the rotor, a stator coil secured to the stator, and a rotor magnet member secured to the rotor opposing the stator coil. The thrust and radial bearings are hydrodynamic bearings. A movable piece that constitutes a part of the thrust bearing is secured to the lower end of a cylindrical portion of the rotor and extended outwardly or inwardly from the cylindrical portion, or is disposed above the rotor. The stator coil is secured to the outer peripheral portion of the support shaft above or below the radial bearing. The rotor magnet member is securd to the inner peripheral surface or inner top surface of the rotor. Either a radial or axial gap is provided between the stator coil and the rotor magnet member.

Gas dynamic bearing for spindle motor

Growing community of inventors

Tokyo, Japan

Shunichi Aiyoshizawa