A gear device includes an internal gear, an external gear having flexibility configured to partially mesh with the internal gear and rotate around a rotation axis relatively to the internal gear, and a wave generator configured to come into contact with an inner circumferential surface of the external gear and move a meshing position of the internal gear and the external gear in a circumferential direction around the rotation axis. The external gear includes a cylindrical section including a first end portion with which the wave generator is in contact and a second end portion adjacent to the first end portion along the rotation axis. An inner circumferential surface of the first end portion includes a polished surface. An inner circumferential surface of the second end portion includes a lathe-cut surface.

A strain wave gear speed reducer unit includes: a casing extending in the axial direction; an internal gear disposed to be rotatable relative to the casing and having internal teeth on the inner circumference; a flexible external gear disposed to the inside of the internal gear in the radial direction, an end of which is fixed to the casing on one side in the axial direction, and which has external teeth on the outer circumference for meshing with the internal teeth; a cam disposed to the inside of the external gear in the radial direction and deforming the external gear in the radial direction by rotating together with a rotating shaft of a motor unit; a connecting part formed integrally with the cam and connected to the rotating shaft on the inside of the external gear; and a support connected to the casing and rotatably supporting the connecting part.

A strain wave gearing, comprising an elastic gear retained by a housing component, wherein a connection between the elastic gear and the housing component has a first play in a circumferential direction and a second play in an axial and radial direction with respect to a center axis of rotation of the elastic gear, wherein the first play is an amount less than the second play.

A variable-speed gear arrangement for a vehicle includes a harmonic drive device, a driven wheel and an optional stop disk. The stop disk can be arranged between the driven wheel and a shaft, with a fastener for connecting the shaft to the stop disk and the driven wheel. The fastener presses the shaft, the stop disk and the driven wheel together in an axial direction. The driven wheel and/or the shaft and/or the stop disk includes a deformation section, and the deformation section includes a contact surface and a deformation surface. In a first state of assembly, the deformation section brings a member of the clamping connection into contact with the contact surface, simultaneously forming a free deformation region. In a second state of assembly, the contact surface and the deformation surface are applied to the member of the clamping connection in a flat manner.

A harmonic ring gear system can include at least one inner gear with external toothing, the at least one inner gear defining an axis of rotation; at least one outer gear with internal toothing arranged concentrically to the at least one inner gear about the axis of rotation, the internal toothing spaced apart from the external toothing; a pin ring positioned between the at least one inner gear and the at least one outer gear, the pin ring comprising a multiplicity of pins; and a rotary transmitter configured to lift a portion of the pins of the multiplicity of pins off the external toothing and press the portion of the pins into the internal toothing.

An elastic transmission element is part of a strain wave gear. Such strain wave gears are also referred to as Harmonic Drives. The elastic transmission element is also referred to as a flexspline and has an outer toothing (03). The elastic transmission element is equipped with at least one strain gauge (04) for measuring a mechanical strain on the elastic transmission element. The one strain gauge (04) or the plurality of strain gauges (04) extends at least as a whole about a circumference of a lateral surface or an axial lateral face of the elastic transmission element.

Provided is a method for producing a gear including an intermediate product forming process of solidifying a fluid material to form a gear intermediate product, and a tooth forming process of cutting the gear intermediate product to form teeth.

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).

The present application discloses a double-flexspline harmonic reducer, comprising a strong flexspline (3), a weak flexspline (2), a wave generator (1), and a deformation stopper (4) of the strong flexspline; the strong flexspline and the weak flexspline are coaxially fixed axially and radially, the strong flexspline and the weak flexspline are respectively provided with teeth that can engage with each other; the number of teeth of the strong flexspline and the weak flexspline are different; the wave generator is used to make the weak flexspline to undergo non-circular elastic deformation and partially engage with the strong flexspline; the contact part of the strong flexspline and the weak flexspline is subjected to the radial pressure of the weak flexspline to generate a non-circular elastic deformation, a flexible tubular wall of the strong flexspline has a toothless surface, and a limiting contact surface is processed on the toothless surface.

A harmonic gear drive includes an input shaft and an output shaft. The input shaft is mechanically coupled to a wave generator which has a varying diameter. The wave generator is positioned within a flex spline which includes external teeth. The external teeth of the flex spline engage with internal teeth of a fixed spline and an output spline when the major diameter of the wave generator is aligned therewith. The output spline has a different number of teeth from the input spline such that, as the wave generator is rotated and the flex spline rotates, the output spline is rotated relative to the fixed spline.