Ntn Corporation

Other

Terumo Kabushiki Kaisha

Tsugito Nakazeki

Toshihiko Nojiri

Teruaki Akamatsu

Takayoshi Ozaki

Hiroyuki Yamada

Kazuo Okamura

Hiroyoshi Ito

Minoru Suzuki

Natsuhiko Mori

Isao Komori

Tomoshige Kobayashi

Motoharu Niki

Masakazu Hirata

Kimihiko Hajota

Saburo Oshima

Tetsuo Hiura, Deceased

Yuji Yada

Yoshinobu Yasuda

Yoshihide Umetsu

Hironori Itsusaki

An air cycle refrigerating/cooling system includes a first heat exchanger for cooling air, a turbine unit that has a compressor for compressing the air and an expansion turbine for adiabatically expanding the air, and a second heat exchanger for cooling the air. A compressor rotor of the compressor and a turbine rotor of the expansion turbine are attached to a common main shaft in the turbine unit in such a manner that the turbine unit drives the compressor rotor with a power generated by the turbine rotor, and the main shaft is rotatably supported by a rolling contact bearing. A part or the entirety of a thrust force applied to the main shaft is supported by an electromagnet, and a pressure equalizing device for equalizing a gas pressure at opposite ends of the rolling contact bearing is provided.

Air cycle refrigerating/cooling system and turbine unit used therefor

The air cycle refrigerating/cooling system compresses air that has flown in with a compressor () in a turbine unit () and adiabatically expands the air with an expansion turbine () in a turbine unit (). In the turbine unit (), a compressor rotor () of the compressor () and a turbine rotor () of the expansion turbine () are attached to the same main shaft (), the main shaft () is supported by bearings () and () so as to be freely rotatable, and part or the entirety of the thrust force applied to this main shaft () is supported by an electromagnet ().

A compressor rotorand a turbine rotorare respectively attached at either end of the main shaftso that the compressor rotoris driven by the power generated by the turbine rotor. The main shaftis supported by rolling contact bearingsandrelative to the radial direction. The thrust force applied to the main shaftis supported by electromagnets. A sensoris provided to detect the thrust force which affects the main shaftthrough air within the compressorand the expansion turbine. In the sensor, sensor elements having the properties changeable in accordance with a pressing force and capable to electrically detect the change in the properties are arranged in a circumferential direction of the main shaft. The sensordetects the thrust force from the output of the sensor elements.

Turbine unit for refrigerating/cooling air cycle

An electric direct-acting actuator is proposed which can maintain a large power increasing function without mounting a separate speed reducer. A plurality of planetary rollers () are disposed between the radially outer surface of a rotor shaft () of an electric motor and the radially inner surface of an outer ring member () fixed in position around the rotor shaft () so as to be rotatable about the rotor shaft () and about their own axes when the rotor shaft () rotates. A helical rib is defined by a rib member () engaged in a helical groove () formed in the radially inner surface of the outer ring member (). The helical rib is engaged in circumferential grooves () formed in the radially outer surface of each planetary roller () at the same pitch as the turns of the helical rib. Thus, the rotary motion of the rotor shaft () is converted to a linear motion of the planetary rollers (), so that it is possible to ensure a large power increasing function without mounting a separate speed reducer.

Electric direct-acting actuator and electric brake device

A traction drive type continuously variable transmission, comprising a first input/output shaft () rotatably supported on a casing (), a second input/output shaft () rotatably supported on the casing (), a V-pulley () supported on the first input/output shaft () and having a pair of pulley members forming a V-groove with variable grove width, a ring () engaged with the V-pulley () and supported at the outer periphery thereof, and a mechanism for moving the ring () to the periphery of the second input/output shaft ().

Traction drive type continuously variable transmission

In the dynamic bearing device, a chamfer having a larger percentage of surface openings is continuous to the outer diameter side of a lower end surface of a bearing member, which constitutes a thrust bearing gap of a first thrust bearing part. A lubricating oil in pores of the bearing member is supplied to a gap portion through the surface openings of the chamfer, so that the gap portion can be kept at a positive pressure without becoming a negative pressure.

Dynamic bearing device and motor having the same

A hydrodynamic type bearing unit comprises a shaft member , a bearing member and a bearing clearance formed between the shaft member and a bearing member to produce a hydrodynamic pressure during the rotation of a shaft member . The bearing clearance is composed of a first clearance C on one axial side and a second clearance C on the other axial side and the first and second clearances C and C are mutually oppositely inclined against an axial direction.

Hydrodynamic type bearing unit

A hydrodynamic type bearing unit with enhanced moment load capacity. In the bearing unit, a radial bearing clearance and thrust bearing clearances are set at such widths that a tilted spindle member comes into contact at the outer periphery of its spindle with both axial ends of a radial bearing surface opposed thereto, as well as at the rims of both end faces of its flange portion with respective thrust bearing surfaces opposed thereto, so that the moment load can by supported by both the radial bearing part and the thrust bearing part. Specifically, the radial bearing clearance &dgr; and the thrust bearing clearances &dgr; are set in accordance with the expression D&dgr; /L&plus;&egr;&gE;&dgr; &gE;D&dgr; /L (where D is the diameter of the flange portion, L is the axial length of the radial bearing part, and &egr; is a machining error).

A dynamic pressure bearing-unit is provided, which includes a shaft member ( ) with a shaft ( ) and a flange portion ( ), a radial bearing ( ) for supporting the shaft member ( ) in the radial direction, and a thrust bearing ( ) for supporting the flange portion ( ) of the shaft member ( ) in the direction of thrust. The radial bearing ( ) and the thrust bearing ( ) support the shaft member ( ) by dynamic pressure action out of contact, respectively, and the shaft ( ) and the flange portion ( ) are constructed in one piece. In this case, dynamic pressure grooves of the thrust bearing ( ) are provided on the end surface of the bearing member ( ) or on the upper surface of the thrust support portion ( ) opposite to the flange portion ( ).

Dynamic pressure bearing-unit

When a current is set, a PI control portion performs proportional integration control, a power amplifying circuit performs power amplification, whereby a current flowing through a motor is controlled to have a constant value. Further, the changes of the number of rotation is positively feedback and the changes are added to the set current by an adder. Further, blood viscosity is detected by a viscosity detecting circuit, an amount of correction is calculated by a correcting amount operating circuit so that it becomes equal to a reference value, and the calculated correcting amount is added to the adder.

Method of controlling blood pump

A ball bearing cage fitted in a pulley main body having peripheral surface to be contacted by a belt. The pulley bearing includes a raceway surface and grease. The cage has pockets for receiving balls which are circumferentially disposed with unequal pitch such that when some of the vibrating balls impart channeling to the grease on the raceway surface, the other balls ride on the grease on the raceway surface. This suppresses or prevents the occurrence of cold peculiar sound.

Pulley

A centrifugal fluid pump assembly includes a housing having fluid inlet and outlet ports and an impeller having magnetic pieces disposed therein and accommodated for rotation in the housing for feeding the fluid, typically blood by a centrifugal force developed during rotation. A rotational torque generating mechanism including a rotor having magnets for attracting the magnetic pieces in the impeller and a motor for rotating the rotor serves to impart a rotational torque to the impeller in a non-contact relationship for thereby rotating the impeller. The impeller has vanes which define radially outwardly extending fluid passages therebetween. The magnetic pieces are embedded in the vanes.

Centrifugal blood pump assembly having magnetic material embedded in

A revolving speed detecting device for use with a rolling contact bearing having a rotary ring and a fixed ring. It has a magnetic ring provided on the peripheral surface thereof with a plurality of teeth at equal pitches and mounted on the rotary bearing ring. A sensor made of soft ferrite or by laminating a plurality of silicon steel plates is mounted on the fixed bearing ring opposite to the teeth of the magnetic ring. A coil is wound around the sensor. A high-frequency voltage generator is connected to the coil. A detecting device for detecting the output voltage of the coil is also connected to the coil.

Revolving speed detecting device with reduced eddy current loss

A centrifugal blood pump assembly according to one aspect of the invention includes a housing, an impeller adapted to rotate within the housing for feeding blood, an impeller position control device, and an impeller rotation torque generating device. The impeller rotates without contacting the inner surface of the housing when the position control device and torque generating device are operative. Even when the position control device is inoperative, operation of the torque generating device enables rotation of the impeller while a blood flowpath is defined between the surface of the impeller facing the torque generating device and the inner surface of the housing. A centrifugal blood pump assembly according to another aspect of the invention involves a pump including a housing having blood inlet and outlet ports and an impeller adapted to rotate within the housing for feeding blood. The assembly also includes an uncontrolled magnetic bearing arrangement for the impeller, and controlled magnetic bearing arrangement for the impeller. The bearing arrangements are removably mounted to the pump.

Centrifugal blood pump assembly

Permanent magnets are buried on one side of an impeller, and a rotor having permanent magnets buried opposite thereto is provided to form a passive bearing. On the other side of the impeller, three electromagnet coils and three position sensors are circumferentially provided at equal distances to form an active bearing, the outputs of the three position sensors are operated to produce impeller displacements, which are fed back to drive the coils.

Growing community of inventors

Kuwana, Japan

Tsugito Nakazeki