Abstract: A machine tool is provided in which a movable member can be moved in an optimum state according to an axial traverse mode. A vertical machining center as the machine tool includes a column provided upright on a bed, a spindle head supported on a front face of the column, a saddle provided in front of the column on the bed, and a table provided on the saddle. The saddle and the table are respectively guided in their movement directions by hydrostatic slideways. When the saddle and the table are moved in a so-called cutting feed mode, pressurized oil is automatically supplied to the respective hydrostatic slideways at a lower pressure. When the saddle and the table are moved in a so-called rapid traverse mode, the pressurized oil is automatically supplied to the respective hydrostatic slideways at a higher pressure.

Abstract: 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 ½ 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.

Abstract: 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 ½ 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.

Abstract: 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 bering rigidity in the other 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 ½ or less of the bearing width of the ball bearing, whereby the radial rigidity of a ball bearing device is made greatly small as compared with the radial rigidity in the prior art and as the result, the stability of a swing arm system can be enhanced and the higher speed and higher accuracy of control become possible.

Abstract: 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 bering rigidity in the other 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 ½ or less of the bearing width of the ball bearing, whereby the radial rigidity of a ball bearing device is made greatly small as compared with the radial rigidity in the prior art and as the result, the stability of a swing arm system can be enhanced and the higher speed and higher accuracy of control become possible.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An electrocardiographic waveform recorder, analyzer, printer and display for superimposing in synchronization, for a predetermined period of time, ECG waveforms. The waveforms are superimposed and synchronized with a predetermined characteristic ECG point (the R-wave peak point) and a plural number of waveforms are expressed while the superimposed positions, at which they are expressed, is changed at fixed intervals of the waveforms, permitting state of deviation recognition.In addition, an ST trend graph and a heart rate output are used for comparisons with environmental conditions. Also, data is recorded continuously over time and displayed and printed at intervals corresponding to the occurrence of the characteristic point of the waveform which permits change in the superimposed waveform display positions. A P wave, a T wave and a QRS wave can be extracted, along with their crest values and the crest value at an arbitrary position in an ST region.

Abstract: 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.