Abstract: In this wave generator for a strain wave gearing, a plug thereof is configured from a plurality of split plug segments that are joined in the axial direction. Wave gearings are installed to the split outer peripheral surfaces of the split plug segments by press fitting, and thereafter the split plug segments can be joined in the axial direction. It is possible to easily produce the wave generator in which a plurality of wave bearings are press fitted, in parallel arrangement, on the non-circular outer peripheral surface.

Abstract: A hollow-type strain wave gearing unit has a cup-shaped flexible externally-toothed gear, in which one shaft end portion of a hollow rotation shaft of a wave generator is located. The shaft end portion is supported by a bearing mounted on a bearing holder fixed to a boss of the flexible externally-toothed gear. The bearing holder has a retainer holding portion to prevent a retainer of a wave generator bearing from coming off in the axis line direction. There is no need to dispose a retainer holding plate of the wave generator bearing inside the flexible externally-toothed gear, whereby the axial length of the hollow-type strain wave gearing unit can be reduced.

Abstract: A strain wave gearing unit is provided with an internal gear, which surrounds the periphery of a cup-shaped external gear, and a bearing. An annular gap is formed between the inner ring of the bearing and the internal gear. The gap communicates with the sliding portions of the bearing and the section where the two gears mesh. An annular filter member made of non-woven fabric is fitted in the gap. Foreign matter such as abrasion powder, which is contained in lubricant that flows in the gap, is trapped by the filter member. The present invention can prevent penetration of abrasion powder generated in the sliding portions into the meshing section via the gap.

Abstract: A wave generator of a hollow strain wave gearing has a rigid plug and a needle roller bearing. The needle roller bearing has an inner ring trajectory surface formed in the plug external peripheral surface, a flexible outer ring, an outer ring trajectory surface formed in an inner peripheral surface of the outer ring, and needle rollers. An inner ring trajectory groove is formed in the plug external peripheral surface, and the inner ring trajectory surface is formed in a groove bottom surface of the inner ring trajectory groove. Inner-ring-side restricting surfaces for restricting the needle rollers from moving in the center axis direction are formed in groove side surfaces on both sides of the inner ring trajectory groove. A wave generator can be obtained, which is suitable for increasing the hollow diameter of a strain wave gearing.

Abstract: A press plate is tacked to a boss of a cup-shaped flexible externally toothed gear of a wave gear device unit. A second arm as a driven member is attached by a fastening bolt to an end surface on an outer side of an output flange of the wave gear device unit. The fastening bolt is screwed into and secured in a tap hole of the press plate from each bolt insertion hole of the second arm, via a flange-side bolt insertion hole and a boss-side bolt insertion hole. A fastening structure can be achieved in which a driven member is fastened to a wave gear device unit in which holes are easily machined into the output flange, and only a few fastening bolts are needed to fasten the boss, the output flange, and the driven member.

Abstract: A hollow-type strain wave gearing unit (1) has a sealing member (14) for sealing a gap (15) opening to the inner peripheral surface of a unit hollow portion (5) passing through in an axis (1a) direction. The gap (15) includes a gap section (15b) between an outer peripheral side end race (48b) on the wave generator side and a boss side end face (108), both faces opposing each other in the axis (1a) direction, and the sealing member (14) is assembled therein. The gap section (15b) is formed in a state partially entering the inside of the inner ring (11b) of the second bearing (11) supporting the wave generator (4). It is possible to realize a hollow-type strain wave gearing unit with a sealing mechanism that is suitable for increasing the inner diameter of the unit hollow portion and for reducing the unit axial length.

Abstract: A wave generator of a strain wave gearing has a rigid plug and a needle roller bearing mounted on the plug external peripheral surface. The plug external peripheral surface has a retainer engaging part for engaging with a retainer that would move in an axis line direction and for restricting the movement thereof along the axis line direction. The retainer has an outer ring engaging part for engaging with an outer ring that would move in the axis line direction and for restricting the movement thereof along the axis line direction. The movements of the retainer and the outer ring can be restricted without providing a separate member. A wave generator of a strain way gearing can be realized, which is provided with a roller bearing capable of restricting the movement of the outer ring with a simple structure.

Abstract: A reduction drive-side mounting end face on a strain wave gearing reduction drive unit has a circular center hole, and a motor-side mounting end face on a motor has a circular projection. The strain wave gearing reduction drive unit and motor are coaxially mounted by the circular projection being fit into the circular center hole with a regulating ring therebetween. The regulating ring, which regulates the motion of a flexible external gear, can be easily mounted to the strain wave gearing reduction drive unit by using the motor. The strain wave gearing reduction drive unit can be mounted to a motor comprising a circular projection with a different outer diameter by using a regulating ring with a different inner diameter.

Abstract: The externally toothed gear of the strain wave gear device is provided with first external teeth, which are capable of meshing with first internal teeth on the stationary side, and second external teeth, which are capable of meshing with second internal teeth on the driving side. The numbers of the first and second external teeth differ. The number of the first internal teeth is greater than the number of the first external teeth. The number of the second internal teeth is less than the number of the second external teeth. Using the externally toothed gear, which is provided with first and second external teeth that differ in number, a strain wave gear device with a low reduction ratio in which the velocity ratio is less than 30 can be achieved.

Abstract: A first shaft end of a hollow shaft of a hollow strain wave gearing is supported by a first support bearing with a collar interposed therebetween which is mounted to the outer-circumferential surface of the first shaft end. A second shaft end on the other end of the hollow shaft is supported by a second support bearing. A wave plug of a wave generator is integrally formed with the hollow shaft, and a wave bearing is mounted on the elliptical outer-circumferential surface thereof from the first-shaft-end side. It is possible to use a first support bearing having an inner diameter larger than the outer diameter of the first shaft end as the first support bearing for supporting the first shaft end.

Abstract: A flat strain wave gearing device equipped with: a first internal gear and a second internal gear; a flexible tubular external gear; and an elliptically shaped wave generator. In the direction of a central axis, the center of support of the external teeth by the wave generator is offset, by an offset amount of ? along the direction of the central axis, with respect to the tooth-width center of the external teeth of the external gear. By setting the offset direction and the offset amount appropriately it is possible to achieve a strain wave gearing device which is suitable in terms of the operating conditions and the mechanical characteristics of the first and second internal gears.

Abstract: A wave generator (5) for a flat-type strain wave gearing (1) has a first elliptical outer circumferential surface (6S) of a first wave generator portion (5S) defined by a first elliptical curve (C1), and a second elliptical outer circumferential surface (6D) of a second wave generator section (5D) defined by a second elliptical curve (C2). Compared to using a wave generator for which the contour is defined by a single elliptical curve, differences between the ball load distribution of the first wave generator portion (5S) and the ball load distribution of the second wave generator portion (5D) can be suppressed, both ball load distributions can be equalized, and the equivalent ball load can be reduced; therefore, an increase in the lifespan of the wave generator bearing can be achieved.

Abstract: A hollow-type strain wave gearing unit has a cup-shaped flexible externally-toothed gear, in which one shaft end portion of a hollow rotation shaft of a wave generator is located. The shaft end portion is supported by a bearing mounted on a bearing holder fixed to a boss of the flexible externally-toothed gear. The bearing holder has a retainer holding portion to prevent a retainer of a wave generator bearing from coming off in the axis line direction. There is no need to dispose a retainer holding plate of the wave generator bearing inside the flexible externally-toothed gear, whereby the axial length of the hollow-type strain wave gearing unit can be reduced.

Abstract: In this hollow strain wave gearing unit, a shaft end part of a hollow rotary shaft of a wave generator is located inside a cup-shaped flexible external gear. The shaft end part is supported by a bearing attached to a bearing holder that is fixed to a boss of the flexible external gear. In the bearing holder, an elastic leaf spring part that is displaceable in the axial direction constitutes a part that supports a holder body part that holds the bearing. A preload is applied by the leaf spring part to the bearing in the axial direction. Thus, there is no need to separately arrange a preload application member inside the flexible external gear, and the axial length of the hollow strain wave gearing unit can be shortened.

Abstract: A wave generator of a strain wave gearing has a rigid plug and a needle roller bearing mounted on the plug external peripheral surface. The plug external peripheral surface has a retainer engaging part for engaging with a retainer that would move in an axis line direction and for restricting the movement thereof along the axis line direction. The retainer has an outer ring engaging part for engaging with an outer ring that would move in the axis line direction and for restricting the movement thereof along the axis line direction. The movements of the retainer and the outer ring can be restricted without providing a separate member. A wave generator of a strain way gearing can be realized, which is provided with a roller bearing capable of restricting the movement of the outer ring with a simple structure.

Abstract: A wave generator of a hollow strain wave gearing has a rigid plug and a needle roller bearing. The needle roller bearing has an inner ring trajectory surface formed in the plug external peripheral surface, a flexible outer ring, an outer ring trajectory surface formed in an inner peripheral surface of the outer ring, and needle rollers. An inner ring trajectory groove is formed in the plug external peripheral surface, and the inner ring trajectory surface is formed in a groove bottom surface of the inner ring trajectory groove. Inner-ring-side restricting surfaces for restricting the needle rollers from moving in the center axis direction are formed in groove side surfaces on both sides of the inner ring trajectory groove. A wave generator can be obtained, which is suitable for increasing the hollow diameter of a strain wave gearing.

Abstract: A hollow-type strain wave gearing unit (1) has a sealing member (14) for sealing a gap (15) opening to the inner peripheral surface of a unit hollow portion (5) passing through in an axis (1a) direction. The gap (15) includes a gap section (15b) between an outer peripheral side end race (48b) on the wave generator side and a boss side end face (108), both faces opposing each other in the axis (1a) direction, and the sealing member (14) is assembled therein. The gap section (15b) is formed in a state partially entering the inside of the inner ring (11b) of the second bearing (11) supporting the wave generator (4). It is possible to realize a hollow-type strain wave gearing unit with a sealing mechanism that is suitable for increasing the inner diameter of the unit hollow portion and for reducing the unit axial length.

Abstract: A wave generator of a strain wave gearing has a plug, a wave generator bearing mounted to an outer peripheral surface of the plug, an input shaft protruding from the center of the plug to a first side running along a center axis, and a bearing arrangement on which a support bearing supporting the input shaft is arranged. Relative to an outer ring end surface of the wave generator bearing that faces the first side, a center-side plug end surface of a plug end surface facing the same direction is in a position withdrawn from the first side toward the opposite direction. The bearing arrangement is provided between the center-side plug end surface and the outer ring end surface encircling the input shaft. The input shaft can be fitted within the width dimension of the wave generator, and a strain wave gearing having a short axial length can be achieved.

Abstract: A strain wave gearing unit is provided with an internal gear, which surrounds the periphery of a cup-shaped external gear, and a bearing. An annular gap is formed between the inner ring of the bearing and the internal gear. The gap communicates with the sliding portions of the bearing and the section where the two gears mesh. An annular filter member made of non-woven fabric is fitted in the gap. Foreign matter such as abrasion powder, which is contained in lubricant that flows in the gap, is trapped by the filter member. The present invention can prevent penetration of abrasion powder generated in the sliding portions into the meshing section via the gap.

Abstract: A first shaft end of a hollow shaft of a hollow strain wave gearing is supported by a first support bearing with a collar interposed therebetween which is mounted to the outer-circumferential surface of the first shaft end. A second shaft end on the other end of the hollow shaft is supported by a second support bearing. A wave plug of a wave generator is integrally formed with the hollow shaft, and a wave bearing is mounted on the elliptical outer-circumferential surface thereof from the first-shaft-end side. It is possible to use a first support bearing having an inner diameter larger than the outer diameter of the first shaft end as the first support bearing for supporting the first shaft end.