Ntn Corporation

Kazutoyo Murakami

Masaki Egami

Tatsuo Nakajima

Kouya Oohira

Arito Matsui

Kenji Ito

Fuminori Satoji

Isao Komori

Eiichirou Shimazu

Yoshihide Himeno

Eiichiro Shimizu

A fluid dynamic bearing apparatus with an increased adhesive strength between a component having an adhesion fixing face and a bracket is provided by appropriately controlling the adhesion gap. Materials for a bracket and a housing are selected so that the value obtained by dividing the linear expansion coefficient of the housing fixed to the inner periphery of the bracket by the linear expansion coefficient of the bracket having a portion for mounting a stator coil of a motor is not lower than 0.5 but not higher than 2.0. An adhesion fixing face formed on the outer periphery of the housing is adhesively fixed to the inner circumferential surface of the bracket with an anaerobic adhesive or an epoxy-based adhesive.

Fluid dynamic bearing apparatus and motor comprising the same

The present invention provides a pore-sealing agent and a member of coating a spray deposit. The pore-sealing agent is excellent in permeability into pores (gaps) of a spray deposit and can be favorably filled thereinto and is capable of sealing pores until gaps in a spray deposit material are substantially entirely filled. The pore-sealing agent contains an epoxy group-containing component and a hardener and does not contain a polymerizable vinyl group-containing solvent. The epoxy group-containing component is a mixture containing a polyglycidyl ether compound in which the number of epoxy groups contained in one molecule is not less than three as and, an alkylenediglycidyl ether compound or a cyclic aliphatic diepoxy compound, both of which contain two epoxy groups in one molecule thereof. Excluding the hardener, the mixing ratio of the polyglycidyl ether compound to the epoxy group-containing component of the mixture is 10 to 95 wt %.

Pore sealing agent, member for coating spray deposit, and bearing

The present invention provides a member for a rolling bearing () which is capable of decreasing the amount of carbon dioxide generated from a polymeric member in discarding the rolling bearing, contributing to restraint or prevention of an increase in the concentration of the carbon dioxide in the atmosphere or a decrease of the concentration thereof in the atmosphere, and allows a continuous use temperature to be high and an endurance time to be long and a rolling bearing using the member. The member for the rolling bearing () is composed of a molding of a polymeric elastic body or a synthetic resin composition. The member is at least one member selected from among an inner ring (), an outer ring (), rolling elements (), a retainer (), and a sealing member (). A raw material derived from a biomass is at least partially used for a producing raw material of a polymeric matrix composing the polymeric elastic body or the synthetic resin composition.

Member for rolling bearing and rolling bearing

Provided is a housing for a resin fluid dynamic bearing device in which deterioration with time of a fixing force for another member is mitigated and which can maintain a high bearing performance for a long period of time. The housing formed of a resin composition exhibiting a compression creep amount of 8% or less when a compressive pressure of 80 MPa is applied for 168 hours at an atmosphere temperature of 80&#xb0; C., provides a sufficient fixing force for the another member fixed with a press-fitting force, for example, a bearing sleeve press-fitted into an inner periphery of the housing even after a long term use. Thus, there is no fear of fixing positions of the another member with respect to the housing being deviated and a high bearing performance is maintained for a long period of time.

Housing for fluid dynamic bearing device

A dynamic bearing device allows production of a smaller housing at low cost and suppresses ion elution from the resin portion to thereby maintain cleanliness in the dynamic bearing device and exert a desired bearing performance. A dynamic bearing deviceis equipped with a bearing sleevefixed to the inner periphery of the housing, and a rotary member rotatable relative to the bearing sleeveand the housing, in which the rotary member is supported in the radial direction and the thrust direction in a non-contact manner by a dynamic pressure action of a lubricant fluid generated in a bearing clearance. The housingis formed by injection molding of a resin composition containing polyphenylene sulfide (PPS) as the base resin and PAN type carbon fibers as a filler.

Dynamic bearing device

A housing for a fluid lubrication bearing apparatus is formed of a resin composition containing polyphenylene sulfide (PPS) as a base resin. The ratio of the base resin to the resin composition is not lower than 40 vol % but not higher than 70 vol %. Moreover, in the composition, an epoxy compound having two or more epoxy groups per molecule of the compound and epoxy value of 0.5 meq/g or more to the resin composition may be added so that the amount of epoxy groups in the resin composition is 8 meq/100 g or more. A carbon fiber may also be added to the resin composition in an amount of not less than 10 vol % but not more than 35 vol %. An inorganic compound may be further added to the resin composition to be the remainder of the resin composition.

Housing for fluid lubrication bearing apparatuses

A magnetic encoder includes a multipolar magnet, having magnetic poles formed therein so as to alternate with each other in a direction circumferentially thereof, and a core metal supporting the multipolar magnet. The multipolar magnet is prepared from a sintered element formed by sintering a powdery mixture of a magnetic powder and a non-magnetic metallic powder. This multipolar magnet is fixed to the core metal to form a unitary component made up of the sintered element and the core metal. The unitary component is subjected to a surface treatment for anticorrosion.

Magnetic encoder and wheel support bearing assembly using the same

To provide an IC-tagged bearing device, in which the IC tag can easily and assuredly fitted to the bearing device and can easily be protected from an environment of elevated temperature. A sealing memberfor sealing a bearing space delimited between inner and outer racesandhas the IC tagattached thereto. The sealing memberincludes a core metalprovided with an elastic element, which is made of rubber or resin, and the IC tagis held embedded in this elastic element. The IC tagmay be fixedly either bonded by vulcanization or engaged in a groove defined in the elastic element

Bearing with IC tag and seal for the same

To provide a magnetic encoder which can be assembled having a thin-walled structure while securing an excellent detection sensitivity and which can provide an excellent moldability by suitably selecting materials, the magnetic encoder is provided which includes a multi-pole magnethaving a plurality of opposite magnetic poles alternating in a direction circumferentially thereof, and a core metalfor supporting the multi-pole magnet. The multi-pole magnetcontains a powdery magnetic material mixed in an amount within the range of 20 to 90 vol. % relative to the total volume of the multi-pole magnet. The multi-pole magnetmay be a sintered magnet.

To substantially eliminate deficiencies such as portions of the resinous coating, where the film thickness is reduced considerably during the press-fitting, and to aim at providing a high productivity with a reduced cost and without the possibility of occurrence of rusting after a prolonged time of use under severe environmental conditions due to an excellent anticorrosive property, a magnetic encoder () includes a multipolar magnet () having a plurality of alternating magnetic poles alternating with each other in a direction circumferentially thereof, and a core metal () supporting the multipolar magnet (). The multipolar magnet () is formed of a sintered element prepared by mixing and sintering a powdery mixture of a magnetic powder and a non-magnetic metallic powder. The multipolar magnet () is fixed on the core metal () by staking a portion of the core metal (), and a sintered element/core metal assembly () fixed on the core metal () is surface treated to have with an anticorrosive resinous coating () for anticorrosive purpose. When the magnetic encoder is press-fitted on an encoder carrier member, one of a press-fitting punch and the magnetic encoder () is heated to a temperature within the range of 60 to 150&#xb0; C.

Magnetic encoder and wheel support bearing assembly utilizing the same

To provide a wheel support bearing assembly capable of securing a satisfactory sealability and of accomplishing an assured press-fit of an magnetic encoder, the wheel support bearing assembly for supporting a vehicle wheel rotatably relative to a vehicle body structure includes an outer member, an inner memberpositioned inside the outer memberwith an annular bearing space delimited between it and the outer member, and rows of rolling elementsrollingly within the annular bearing space. At least one sealing unitis provided for sealing one of opposite open ends of the annular bearing space. This sealing unitis comprised in part of a magnetic encoderincluding a multi-pole magnet memberhaving a plurality of opposite magnetic poles alternating in a direction circumferentially thereof and a first sealing plateserving as a core metal. The first sealing plateis press-fitted onto the inner memberwith the amount of interference fit to be within the range of 5 to 230 &#x3bc;m.

Growing community of inventors

Iwata, Japan

Kazutoyo Murakami