Nsk Corporation

Nippon Seiko Kabushiki Kaisha

Chuichi Sato

Katsuhiko Tanaka

Shigeru Endo

Hiromitsu Muraki

Katsuhisa Tonooka

Hiroyuki Nojima

Yuichi Sumita

Ikunori Sakatani

Mamoru Tanaka

Hiroyuki Sawai

Shoji Noguchi

Gentei Inoue

Masami Shinomoto

Hiroshi Mitsuboshi

Shoji Jibu

Nobuhiro Matsuo

Hiroshi Saito

Akira Kikuchi

Dai Kinno

Tsuyoshi Saito

Hiroyuki Matsuzaki

Shoji Horike

Kunio Kawashima

Tomita Suzuki

Shigemi Tsukamoto

Yoshimitsu Suganuma

Shinichi Takaira

Hidenori Shinno

The locus of the displacement of the centers of the balls of a ball bearing is made elliptical and the radial bearing rigidity of the ball bearing in one radial direction is made greater than the radial bearing rigidity in another radial direction orthogonal to the one radial direction, or at least one of the axial length of the portion on the outer diametral surface of the inner race of the ball bearing which is fitted to a shaft and the axial length of the portion on the outer diametral surface of the outer race of the ball bearing which is fitted to a housing is made &frac12; or less of the bearing width of the ball bearing, whereby the radial rigidity of a ball bearing device is made very small as compared with the radial rigidity in the prior art. As a result, the stability of a swing arm system can be enhanced and higher speed and higher accuracy of control become possible.

Method of stabilizing high-speed control of ball bearing device

The locus of the displacement of the centers of the balls of a ball bearing is made elliptical and the radial bearing rigidity of the ball bearing in one radial direction is made greater than the radial bearing rigidity in another radial direction orthogonal to the one radial direction, or at least one of the axial length of the portion on the inner diametral surface of the inner race of the ball bearing which is fitted to a shaft and the axial length of the portion on the outer diametral surface of the outer race of the ball bearing which is fitted to a housing is made &frac12; or less of the bearing width of the ball bearing, whereby the radial rigidity of a ball bearing device is made very small as compared with the radial rigidity in the prior art. As a result, the stability of a swing arm system can be enhanced and the higher speed and higher accuracy of control become possible.

Ball bearing device for a swing arm

As a ball for ball bearing there is provided a ceramics-coated ball made of a steel having almost the same linear thermal expansion coefficient as that of the bearing ring of the ball bearing and coated with a ceramics material. In this arrangement, even when the temperature during bearing assembly and the working temperature differs from each other, the release of preload or excessive preload can be prevented as in ceramics ball because the bearing and the ball can expand or shrink in the same manner. Further, since the ball and the bearing ring contact with each other via the ceramics layer, fretting abrasion can be prevented, making it possible to obtain excellent running performance and acoustic properties.

Rolling bearing and bearing device

In an annular member forming apparatus including: a forming roll rotatable in contact with an outer cylindrical surface of an annular workpiece; a mandrel relatively movable towards and away from the forming roll in contact with an inner cylindrical surface of the workpiece; and an outside diameter detecting device for detecting an outside diameter of the workpiece which is to be worked, the apparatus further includes a moving device for moving relatively the forming roll and the mandrel and for pressing the workpiece by the forming roll and the mandrel moved towards each other to subject the workpiece to rough rolling and to finish rolling. The moving device includes a retracting device for correcting an elastic deformation of the forming roll, the mandrel and the moving device occurring during the rough rolling, for a switching time from the rough rolling to the finish rolling by an output signal from the outside diameter detecting device. The moving device is moved backwardly away from the mandrel by a distance corresponding to a difference between amounts of elongation which are due to a rolling load during the rough rolling and due to a rolling load during the finish rolling for the switching time.

Apparatus and method of forming an annular member

A ball polishing method includes the steps of rotating one of two plates through use of a rotating mechanism while balls are sandwiched between the plates, pressing one of the two plates against the other plate via a guide slide mechanism for guiding one of the two plates to the other plate by means of a pressing mechanism, and polishing the balls while the pressing force is regulated through use of a pressing force control mechanism. The method is further provided with rotary support means for supporting the rotating mechanism and guide support means for supporting the guide slide mechanism, and at least one of them utilizes hydrostatics. By virtue of this method, a machining pressure can be controlled with a high degree of accuracy, and the accuracy of polishing of balls can be improved.

Method of forming annular grooves in a ball polishing apparatus

In an annular member forming apparatus including: a forming roll rotatable in contact with an outer cylindrical surface of an annular workpiece; a mandrel relatively movable towards and away from the forming roll in contact with an inner cylindrical surface of the workpiece; and an outside diameter detecting device for detecting an outside diameter of the workpiece which is to be worked, the apparatus further includes a moving device for moving relatively the forming roll and the mandrel and for pressing the workpiece by the forming roll and the mandrel moved towards each other to subject the workpiece to rough rolling and to finish rolling. The moving device includes a retracting device for correcting an elastic deformation of the forming roll, the mandrel and the moving is device occurring during the rough rolling, for a switching time from the rough rolling to the finish rolling by an output signal from the outside diameter detecting device. The moving device is moved backwardly away from the mandrel by a distance corresponding to a difference between amounts of elongation which are due to a rolling load during the rough rolling and due to a rolling load during the finish rolling for the switching time.

Apparatus for forming an annular member

The locus of the displacement of the centers of the balls of a ball bearing is made elliptical and the radial bearing rigidity of the ball bearing in one radial direction is made greater than the radial bearing rigidity in another radial direction orthogonal to the one radial direction, or at least one of the axial length of the portion on the inner diametral surface of the inner race of the ball bearing which is fitted to a shaft and the axial length of the portion on the outer diametral surface of the outer race of the ball bearing which is fitted to a housing is made 1/2 or less of the bearing width of the ball bearing, whereby the radial rigidity of a ball bearing device is made very small as compared with the radial rigidity in the prior art. As a result, the stability of a swing arm system can be enhanced and higher speed and higher accuracy of control become possible.

A sphere polisher capable of making uniform conditions under which balls are polished is provided. The inner and outer polishing circuits are defined by the grooves 23 provided on the rotative disc 10 and the fixed disc 20. The storage conveyor 50 is provided with an outer ball guiding passage 55 and an inner ball guiding passage 56. The ball supply chute 57 is provided with the inner chute portion 57a connecting the inner polishing circuits with the outer ball guiding passage 55, and the outer chute portion 57b connecting the outer polishing circuits with the inner ball guiding passage 56. The ball discharge chute 58 is provided with the inner discharge chute portion 58a connecting the inner polishing circuits with the inner ball guiding passage 56, and the outer discharge chute portion 58b connecting the outer polishing circuits with the outer ball guiding passage 57.

Sphere polisher

Ball polishing method and apparatus, and annular groove forming method

In the ball bearing inspection apparatus and method, the butting portion 7c of a skew drive shaft 7 rotatable coaxially with a spindle rotary shaft 1 is butted against steel balls 3 which are respectively held between the respective grooves of the inner ring 4b and outer ring 4a of a ball bearing 4 to be inspected, the spindle rotary shaft 1 is rotated while applying a pre-load to the outer ring 4a by a pre-load ring 5, and the skew drive shaft 7 is rotated while controlling the rotation speed of the skew drive shaft 7 in such a manner that the respective steel balls 3, which are being rotated on their own axes and around the spindle rotary shaft 1 due to the rotation of the spindle rotary shaft 1, is caused to make a skew movement due to the butting portion 7c. Therefore, physical quantities such as vibrations, sound pressures and the like generated from the ball bearing 4 to be inspected are measured in a condition that the respective balls 3 are making their respective skew movements in addition to their rotational movements on their own axes and around the spindle rotary shaft 1.

Apparatus and method for inspecting a ball bearing

In a bore size correcting apparatus, a passing-through jig of an extended type lapping reamer in the bore size trimming device is passed through the bore surface of the workpiece machined by the bore grinding machine to correct the inner size of the workpiece, either one of the bore size to be corrected and a corrected bore size of the workpiece is measured by the bore size measuring device, a signal is outputted in accordance with the corrected bore size, and in response to the output signal, a machining command is supplied from the bore size control device to at least one of the in-process fixed-size control device and the external size control device. Thus, the bore size of the workpiece roughly manufactured by grinding can be precisely finished, with no skill, so as to have any optional set value, and the correction apparatus is also made compact and inexpensive.

Bore size correcting apparatus

An electrorheological fluid damper for a slide mechanism including a base and a table, is made up of base-side conductive arcuate pipes different in diameter (serving as a positive electrode), and table-side conductive arcuate pipes different in diameter (serving as a negative electrode) which are arranged alternately in such a manner that they are coaxial with one another, so that the contact areas of the electrodes which are in contact with the electrorheological fluid are increased without increase of the size of the damper itself. When the table is being slid, no voltage is applied to the electrorheological fluid, so that the viscosity of the electrorheological fluid is minimum, being of only its solution, and when the table is stopped, voltage is applied to the electrorheological fluid, so that the viscosity of the electrorheological fluid is increased. Thus, the electrorheological fluid damper requires no high voltage and is not bulky, and is high both in positioning accuracy and in shock absorbing performance.

Electrorheological fluid damper for a slide mechanism

In order to provide a vacuum degreasing-drying method by which extremely small, precision metal products can be degreased and dried quickly and completely without using organic solvents, according to the present invention, an object 112 to be rinsed is put in a vacuum drier 110 after being rinsed with a hydrocarbon cleaning agent and then the air in the vacuum drier 110 is evacuated so as to degrease and dry the object thus rinsed.

Method and apparatus for drying bearing

In a ball lapping machine in which balls are machined by lapping between two lapping plates, namely a stationary plate and a turn table, the structure is arranged with a central shaft having a common center line with a sleeve rotative around the center shaft, a housing supporting the sleeve rotatively, a stationary plate on which the aforesaid central shaft is mounted, and the turn table on which the aforesaid sleeve is mounted. With such structure, the aforesaid center line is made inclinable at appropriate angles to the vertical.

Ball lapping machine

In superfinishing a Gothic-arch-shaped groove of a nut by using a superfinishing stone attached to the tip end of an oscillation arm while oscillating the superfinishing stone about the oscillation axis and, at the same time, moving the superfinishing stone in the longitudinal direction of the Gothic-arch groove, the oscillation axis is inclined by a predetermined angle with respect to the longitudinal direction of the Gothic-arch groove. The shape of the cross section of the Gothic-arch groove orthogonal to the oscillation axis is regarded as a single circular arc and, thus, both flanks of the Gothic-arch groove can be superfinished simultaneously.

Growing community of inventors

Fujisawa, Japan

Chuichi Sato