A strain wave gear system (10) includes first and second sets of ball bearings (80, 82) located intermediate a flange (84) and a retainer plate (88) rotatable with an output (54) and a radially oriented flat disc (74) of the input including strain relief (76). Strain relief (76) is a helical slot in a coupling (70) located radially within the wave generator (94) and the ring gear (22). The ring gear (22) is sealed by a sealing system including sealant (42) forced by a protrusion (34) of the cap (24) entering into a cavity (36) through a channel (40) into a relief volume (38) of the housing (12). The bearing (48) rotatably mounting the housing (12) to the output (54) is lubricated by a lubricating system including plungers (110) threadably received in axial bores (102) intersecting with radial bores (104) in communication with radial holes (47) of the bearing (48).

A strain wave gear system (10) includes first and second sets of ball bearings (80, 82) located intermediate a flange (84) and a retainer plate (88) rotatable with an output (54) and a radially oriented flat disc (74) of the input including strain relief (76). Strain relief (76) is a helical slot in a coupling (70) located radially within the wave generator (94) and the ring gear (22). The ring gear (22) is sealed by a sealing system including sealant (42) forced by a protrusion (34) of the cap (24) entering into a cavity (36) through a channel (40) into a relief volume (38) of the housing (12). The bearing (48) rotatably mounting the housing (12) to the output (54) is lubricated by a lubricating system including plungers (110) threadably received in axial bores (102) intersecting with radial bores (104) in communication with radial holes (47) of the bearing (48).

A centering structure is provided in a device including a first member with an inner peripheral surface and a second member with an outer peripheral surface opposed to the inner peripheral surface. The centering structure includes outer peripheral cam surfaces circumferentially aligned on the inner peripheral surface of the first member, inner peripheral cam surfaces opposed to the outer peripheral cam surfaces, and rolling elements. The inner peripheral cam surfaces form accommodation spaces together with the outer peripheral cam surfaces therebetween. The rolling elements are disposed in the accommodation spaces. Each rolling element rolls along each outer peripheral cam surface and each inner peripheral cam surface. The rolling elements move the first or second member in a direction to cause a center of the inner peripheral surface and a center of the outer peripheral surface to be matched when the first and second members are rotated relative to each other.

A reverse-input blocking clutch includes: a pressed member having a pressed surface; an input member having an input-side engaging portion on an inner side in a radial direction of the pressed surface; an output member having an output-side engaging portion further on the inner side in the radial direction than the input-side engaging portion; an engaging element on the inner side in the radial direction of the pressed surface to move in a first direction away from or toward the pressed surface, having a main engaging element body having a pivot-support shaft, and a link member having a first end portion pivotally linked to the pivot-support shaft and a second end portion pivotally linked to the input-side engaging portion; and an elastic body between the main engaging element body and the link member and applying an elastic force to the link member toward the pressed surface in the first direction.

A reverse input blocking clutch has: a pressed member having a pressed surface; an input member having an input-side engaging portion; an output member having an output-side engaging portion; and an engaging element having an engaging element main body and a link member to move in the first direction away from or toward the pressed surface. The engaging element main body has a pair of main body plates arranged to overlap in the axial direction, and a pivot support shaft arranged on the side in the first direction closer to the pressed surface than the input-side engaging portion with the both side portions supported by the pair of main body plates. One pressing surface facing the pressed surface is provided on one main body plate, and the other pressing surface is provided on the other main body plate.

A strain wave gear system (10) includes first and second sets of ball bearings (80, 82) located intermediate a flange (84) and a retainer plate (88) rotatable with an output (54) and a radially oriented flat disc (74) of the input including strain relief (76). Strain relief (76) is a helical slot in a coupling (70) located radially within the wave generator (94) and the ring gear (22). The ring gear (22) is sealed by a sealing system including sealant (42) forced by a protrusion (34) of the cap (24) entering into a cavity (36) through a channel (40) into a relief volume (38) of the housing (12). The bearing (48) rotatably mounting the housing (12) to the output (54) is lubricated by a lubricating system including plungers (110) threadably received in axial bores (102) intersecting with radial bores (104) in communication with radial holes (47) of the bearing (48).

A strain wave gear system (10) includes first and second sets of ball bearings (80, 82) located intermediate a flange (84) and a retainer plate (88) rotatable with an output (54) and a radially oriented flat disc (74) of the input including strain relief (76). Strain relief (76) is a helical slot in a coupling (70) located radially within the wave generator (94) and the ring gear (22). The ring gear (22) is sealed by a sealing system including sealant (42) forced by a protrusion (34) of the cap (24) entering into a cavity (36) through a channel (40) into a relief volume (38) of the housing (12). The bearing (48) rotatably mounting the housing (12) to the output (54) is lubricated by a lubricating system including plungers (110) threadably received in axial bores (102) intersecting with radial bores (104) in communication with radial holes (47) of the bearing (48).

A reverse input blocking clutch has: a pressed member having a pressed surface; an input member having an input-side engaging portion; an output member having an output-side engaging portion; and an engaging element having an engaging element main body and a link member to move in the first direction away from or toward the pressed surface. The engaging element main body has a pair of main body plates arranged to overlap in the axial direction, and a pivot support shaft arranged on the side in the first direction closer to the pressed surface than the input-side engaging portion with the both side portions supported by the pair of main body plates. One pressing surface facing the pressed surface is provided on one main body plate, and the other pressing surface is provided on the other main body plate.

The reverse input shutoff clutch includes: an input member, an output member coaxially arranged with the input member, a pressed member having a pressed surface, and an engaging element. The engaging element, when rotational torque is inputted to the input member, moves in a direction away from the pressed surface due to engagement with the input member and transmits the rotational torque to the output member, and when rotational torque is reversely inputted to the output member, moves in a direction toward the pressed surface due to engagement with the output member, and prevents or suppresses relative rotation between the output member and the pressed member.

Provided is a reverse input blocking clutch capable of easily releasing a state in which rotation of an output member is prevented or suppressed.

The reverse input blocking clutch 5 includes an input member 14, an output member 15, a pressed member 16, and an engaging member 17. When a rotational torque is inputted to the input member 14, the engaging member 17 moves in a direction away from a pressed surface 28 of the pressed member 16 due to engagement with the input member 14, and transmits the rotational torque inputted to the input member 14 to the output member 15 due to engagement with the output member 15; and when rotational torque is reversely inputted to the output member 15, moves in the direction closer to the pressed surface 28 based on engagement with the output member 15, and by being pressed against the pressed surface 28 does not transmit the rotational torque reversely inputted to the output member 15 to the input member 14, or transmits only part thereof to the input member 14 due to engagement with the input member 14.