47 results about "Strain wave gearing" patented technology

A strain wave gearing (1) is configured to have a unitized structure having a main bearing (5) that supports an internally toothed gear (2) and an externally toothed gear (3) in a manner that allows relative rotation, and an output flange (6) that is linked to the externally toothed gear (3). The externally toothed gear (3) is formed in the shape of a wine glass and ensures a large hollow diameter, which is required in cases where the externally toothed gear (3) is incorporated into a robot joint part or the like. A strain gauge (101) of a torque sensor (100) is attached to an outward-facing end surface portion of the output flange (6) linked to the externally toothed gear (3). The torque sensor (100) is capable of precisely detecting rotational torque without being affected by flexing of the externally toothed gear (3), and elements such as the strain gauge (101) are not exposed to oil, grease, or the like.

In the inner space (9) of the outer gear (3) of the invention's wave gear device (1), a powder supply mechanism (10) is assembled with a press-formed product (12) in which solid lubricant powder is pre-solidified. During operation of the wave gear device (1), the powder supply mechanism (10) wears the press-formed product (12) using a friction plate (13) to supply a small amount of solid lubricant wear powder (11) from the press-formed product (12) for a long period. Loss torque caused by the efficiency reduction due to the invasion of a large amount of solid lubricant powder into the gap of the contact portion (C) of the high-speed rotating wave generator (4) and the like can be suppressed. Thus, the high efficiency state of the powder-lubricated wave gear device can be maintained and its long service life can be achieved.

A strain wave gear device (1) is provided with: a first flange (8) that supports an input shaft (6) via a first support bearing (7); and a second flange (10) that supports the input shaft (6) via a second support bearing (9). The external gear (3) is fastened and fixed to the first flange (8) by means of a first fastening bolt (11), and the internal gear (2) is fastened and fixed to the second flange (10) by means of a second fastening bolt (12). The fastening strength in the radial direction between the externally toothed gear (3) and the first flange (8) by the first fastening bolt (11) is set to a degree equal to or greater than the fastening strength between the internally toothed gear (2) and the second flange (10) by the second fastening bolt (12). As a result, eccentricity between the wave generator (4) and the first and second support bearings (7, 9) caused by radial deformation of the first and second flanges (8, 10) due to a radial load acting from the load side can be suppressed, and excessive radial force can be prevented from acting on the wave generator.

A flat gearing in the form of a strain wave gearing includes a circular spline having an inner toothing; a dynamic spline which is axially adjacent to the circular spline and has an inner toothing; a flexible flexspline which is arranged inside the circular spline and dynamic spline and has at least one outer toothing; and a wave generator which is arranged inside the flexspline for deforming the flexspline in the radial direction. An interlocking, torque-transmitting connection is established between the circular spline and the flexspline at two opposing points on the flexspline and between the flexspline and the dynamic spline at four positions on either side of the contact with the circular spline. The axial course of the radial position of the tooth transverse of the at least one outer toothing of the flexspline has a region which is reduced radially in the direction of a center axis of the flat gearing.

A strain wave gear device (1) is provided with: an input shaft (6) directly connected to a cam plate (41) of a wave generator (4); and first and second support bearings (7, 9) that support the input shaft. The first and second support bearings (7, 9) are attached to the first and second bearing attachment parts (11, 13) in a clearance fit state, respectively. In order to eliminate rattling of the first and second support bearings (7, 9), outer rings of the first and second support bearings (7, 9) are pressed radially inward by first and second elastic rings (12, 14). Eccentricity between the wave generator (4) and the first and second support bearings (7, 9) caused by a load applied from a load side to a second end plate (10), which is an output side member, is absorbed by elastic deformation of the first and second elastic rings (12, 14), thereby preventing unnecessary radial force from being applied to the wave generator (4).

A strain wave gearing includes a wave generator that creates a state in which a flexible externally toothed gear is flexed into a non-circular shape and partially meshes with a rigid internally toothed gear, and that includes a wave plug having a non-circular outer peripheral surface and a wave bearing attached to the non-circular outer peripheral surface of the wave plug. The wave bearing includes an outer ring having an inner peripheral surface and an outer-ring-side raceway surface formed on the inner peripheral surface, an inner ring having an outer peripheral surface and an inner-ring-side raceway surface formed on the outer peripheral surface, and a plurality of rolling elements rotatably inserted between the outer-ring-side raceway surface and the inner-ring-side raceway surface.

A strain wave gearing (1) has a hollow input shaft (5). A wave generator (4), which makes an externally toothed gear (3) flex in the radial direction so as to engage an internally toothed gear (2), has a wave bearing (43) that has a ball retainer (47). An input-shaft outer circumferential surface portion of the hollow input shaft (5) that is positioned on the inside of the externally toothed gear (3) is coated with an oil-repellent coating (14). The surface of the ball retainer (47) is also coated with an oil-repellent coating (15). The oil-repellent coatings (14, 15) lower the grease stirring resistance of the hollow input shaft (5) and the ball retainer (47) and make it possible to reduce loss torque at the strain wave gearing (1).

A strain-gauge-type torque detection part (20) of a strain wave gearing (1) comprises a first torque detection part (20A) and a second torque detection part (20B), which output detection signals of two independent systems. The first and second torque detection parts (20A, 20B) are provided with multiple sets of strain gauges (11) attached to a diaphragm (3c) of an externally toothed gear (3), at predetermined angular intervals around a central axis. A first detection signal (22A) from the first torque detection part (20A) and a second detection signal (22B) from the second torque detection part (20B) are combined after a gain adjustment and a combined signal (23C) is generated. Transmitted torque can be calculated on the basis of the first detection signal (23A), the second detection signal (23B), and the combined signal (23C). Three-system output, resulting from adding high-accuracy output (24C) to detection outputs (24A, 24B) of two independent systems, is obtained from a torque detection device (10).

Provided is a torque detector (5) for a strain wave gear device (1), wherein first and second strain gauges (11, 12), which exhibit an arc shape that expands at an angle of 180 degrees, are affixed to an inner surface (33a) of a deformed (elastically deformed) diaphragm (33) of an externally toothed gear (3). The first and second dummy strain gauges (13, 14) are adhered to an inner surface (34a) of a boss, which is a portion of the external gear (3) where deformation (elastic deformation) does not occur. A full bridge circuit (8) is formed by the four strain gauges. The torque detector for a strain wave gearing device can be easily manufactured and can perform temperature compensation with high precision.

The present invention provides a wave gear device. The wave generator rotates at the same speed as the input component around the central axis. The flexible external tooth gear has a body, external teeth, a diaphragm, and a fixed portion. The body is arranged radially outward from the wave generator and is bent into a non-circular shape by the wave generator. The external teeth are provided on the outer peripheral surface of one axial side of the body. The diaphragm extends radially outward from the end of the other axial side of the body. The fixed portion extends radially outward from the end of the radially outward side of the diaphragm. The internal tooth gear is arranged radially outward from the body and has internal teeth on the inner peripheral surface that mesh with the external tooth portion. The housing is fixed to the fixed portion from the other axial side. One of the internal tooth gear and the flexible external tooth gear is fixed, and the other rotates around the central axis. The sealing component is arranged between the diaphragm and the housing, or between the end of the other axial side of the body and the housing.

A wave generator (1) for a strain wave gearing (20) is disclosed, the wave generator (1) comprising an elliptical inner ring (2) and an elliptical outer ring (4), in which balls are arranged between the elliptical inner ring (2) and the elliptical outer ring (4), in which balls (6) roll on raceways (8) arranged on the elliptical inner ring (2) and the elliptical outer ring (4), wherein the wave generator (1) is virtually divided in cross-section by the axis of rotation (AR) of the ball (6) and an axis (AS) perpendicular to the axis of rotation (AR) of the ball (6) into four quadrants (I, II, III, IV) arranged clockwise, where the ball (6) has four contact points (P-I, P-II, P-III, P-IV) with the raceway (8), and where each contact point (P-I, P-II, P-III, P-IV) is located in one of the four quadrants (I, II, III, IV), wherein the raceway (8) of the elliptical outer ring (4) is located in a first and a second quadrant (I, II), the raceway (8) of the elliptical inner ring (2) is located in a third and a fourth quadrant (III, IV), the center (M-I) of the radius of curvature (R-I) of the raceway (8-I) of the first quadrant (I) is located in the third quadrant (III), and the center (M-II) of the radius of curvature (R-II) of the raceway (8-II) of the second quadrant (II) is located in the fourth quadrant (IV), wherein the center (M-III) of the radius of curvature (R-III) of the raceway (8-III) of the third quadrant (III) is located in the first quadrant (I), and wherein the center (M-IV) of the radius of curvature (R-IV) of the raceway (8-IV) of the fourth quadrant (IV) is located in the second quadrant (II).

In a torque detector (5) for a strain wave gear device (1), first and second strain gauges (11, 12) that have a circular arc shape which subtends an angle of 180 degrees are attached to an inner surface (33a) of a diaphragm (33) which is in an external gear (3) and in which strain (elastic deformation) occurs. First and second dummy strain gauges (13, 14) are attached to an inner surface (34a) of a boss that is a portion which is in the external gear (3) and in which strain (elastic deformation) does not occur. A full bridge circuit (8) is constituted by these four strain gauges. The present invention makes it possible to realize a torque detector for a strain wave gear device which is easily manufactured and which can accurately perform temperature compensation.

A strain wave gearing (1) is configured to have a unitized structure having a main bearing (5) that supports an internally toothed gear (2) and an externally toothed gear (3) in a manner that allows relative rotation, and an output flange (6) that is linked to the externally toothed gear (3). The externally toothed gear (3) is formed in the shape of a wine glass and ensures a large hollow diameter, which is required in cases where the externally toothed gear (3) is incorporated into a robot joint part or the like. A strain gauge (101) of a torque sensor (100) is attached to an outward-facing end surface portion of the output flange (6) linked to the externally toothed gear (3). The torque sensor (100) is capable of precisely detecting rotational torque without being affected by flexing of the externally toothed gear (3), and elements such as the strain gauge (101) are not exposed to oil, grease, or the like.

A strain wave gearing (1) has a hollow input shaft (5). A wave generator (4), which makes an externally toothed gear (3) flex in the radial direction so as to engage an internally toothed gear (2), has a wave bearing (43) that has a ball retainer (47). An input-shaft outer circumferential surface portion of the hollow input shaft (5) that is positioned on the inside of the externally toothed gear (3) is coated with an oil-repellent coating (14). The surface of the ball retainer (47) is also coated with an oil-repellent coating (15). The oil-repellent coatings (14, 15) lower the grease stirring resistance of the hollow input shaft (5) and the ball retainer (47) and make it possible to reduce loss torque at the strain wave gearing (1).

The invention relates to an actuating device (1) for actuating a friction clutch (33) of a differential (30), with which a torque distribution from an input (31) to at least one output can be controlled, comprising: a transmission unit (2) for connecting a drive unit (3) of the actuating device (1) to an output unit (4) of the actuating device (1), wherein the transmission unit (2) has a strain wave gearing. The invention also relates to a differential (30) for a motor vehicle comprising an actuating device (1).

A strain wave gearing device includes a circular spline having a plurality of internal teeth; a flex spline having a plurality of external teeth, the flex spline is disposed coaxially with respect to the circular spline to allow one or more of the plurality of external teeth to engage with one or more of the plurality of internal teeth, wherein the flex spline is defined using Bezier curve defining a plurality of structural parameters associated with the flex spline; and a wave generator having an elliptical cam and a flexible bearing mounted on the elliptical cam, the wave generator is disposed coaxially with respect to the flex spline to allow the flexible bearing to have two-point contact with the flex spline.

Systems and methods for a barrel cam actuator assembly. The barrel cam actuator assembly includes, in one example, a barrel cam including a first track and a strain wave gearing device that is arranged coaxial to the barrel cam and rotationally coupled to the barrel cam. The barrel cam actuator assembly further includes an electric motor rotationally coupled to the strain wave gearing device and configured to selectively rotate the strain wave gearing device. Further, in the barrel cam actuator assembly, the strain wave gearing device includes an outer spline, a flexible inner spline that meshes with the outer spline, and an elliptical wave generator.

An assembly includes at least three strain gauges and is attached to an elastic transmission element of a strain wave gearing. The assembly is designed to measure a torque acting on the elastic transmission element. Output signals from each of the strain gauges are measured. The output signal of one of the strain gauges is predicted from the measured output signals of the other strain gauges. An error message is output based on the predicted output signal deviating from the respective measured output signal by more than a predetermined tolerance.

A mold used for molding a flexible external gear of a strain wave gearing is provided with an outer die and a center die that defines the inner peripheral surface shape of the flexible externally toothed gear. The center die is provided with a die divided part composed of a plurality of divided dies divided in the circumferential direction. Each divided die can be retracted by a divided die movement mechanism from a molding position to a retracted position that is radially inward from the molding position. When the mold is opened after molding, the die divided part as a whole is slightly contracted by retracting each divided die to the radially inward retracted position. The center die can be extracted from the outer die without applying excessive force.

The invention relates to a strain wave gearing (2), comprising a flexspline (6), a circular spline (10), and a wave generator (14) which has a plug (18) and a rolling body bearing (22) surrounding the plug (18), wherein a plurality of measurement grids (28) for strain measurement are arranged on the flexspline (6), wherein the wave generator (14) is designed in such a way that three engagement regions are formed between the toothings of the flexspline (6) and circular spline (10).

A braking assembly for a strain wave gearing of a surgical robotic manipulator, the braking assembly including a first braking member fixedly coupled to an input portion of a strain wave gearing of a surgical robotic manipulator; and a second braking member fixedly coupled to an output portion of the strain wave gearing, and wherein during a braking operation the first braking member contacts the second braking member to mechanically brake the input portion to the output portion.

A strain wave gearing has a detection mechanism that detects thrust force generated between a wave generator and an externally toothed gear. The detection mechanism is provided with a strain gauge or piezoelectric load meter, and a transmission mechanism that transmits thrust force from the wave generator to the load meter. Only rotational force is transmitted to the wave generator from a from a motor shaft side, and axial force is not transmitted. The load meter and the transmission mechanism provide a small and compact detection mechanism that can be incorporated inside the externally toothed gear. In the strain wave gearing into which the detection mechanism is incorporated, operation control according to detected thrust force becomes possible using thrust force information during operation.

A strain wave gearing (100) comprises: a wave generator (1) including a cam (10); a rigid internal gear (2); a flex section (3) including a flexible external gear (31) and a flexible internal gear (32); and a rigid external gear (4). The cam (10) includes N pole sections (N being an integer greater than or equal to 2) located at equal intervals in the circumferential direction about an axis (AX), and N intermediate sections located between pole sections adjacent in the circumferential direction. The wave generator (1) flexes the flexible external gear (31), thereby meshing the flexible external gear (31) with the rigid internal gear (2) in N portions respectively corresponding to the N pole sections. The flexible internal gear (32) is flexed in response to the flexible external gear (31) being flexed by the wave generator (1) and meshes with the rigid external gear (4) in N portions respectively corresponding to the N intermediate sections.

A linear actuating device for a brake caliper adapted to bias at least one brake pad to abut against a braking surface of a brake disc is provided. The linear actuating device has a motor having a rotating drive shaft and a stator, a rotational wave generator of a strain wave gearing of a harmonic transmission, the rotational wave generator being made in one piece with the rotating drive shaft, and a harmonic reducer, the harmonic reducer being elastically deformed and rotated by the rotational wave generator. A rotary-to-linear motion conversion device, adapted to transform a rotary motion into a linear motion adapted to bias the at least one brake pad to abut against the braking surface along an axial direction, is rotatably connected to the harmonic reducer.

The invention relates to the field of strain wave gearing, which is also commonly referred to as "harmonic drive". In order to provide a frictional strain wave gearing which enables the deformation of the flexspline in a simple, mechanical manner, including the generation of the necessary contact forces, so that technically usable forces can be transmitted without significant effort to compensate for mechanical tolerances present in the gearing, a frictional strain wave gearing is proposed, having an outer cylinder, a flexspline and a wave generator, wherein the outer cylinder, the flexspline and the wave generator are in force transmission by frictional contact, which is generated by a pressing force, wherein at least one structure having an elastic shape is formed by a component of the wave generator or the outer cylinder, the elastic shape being hollow in the region of the frictional contact and having a constant wall thickness even when the shape is deformed, wherein the elastic structure is configured to exert the pressing force. The invention also relates to a frictional planetary gearing.

A robot joint assembly and a robotic arm with the joint assembly are disclosed. Also, a robot comprising the robotic arm is disclosed. The joint assembly extends along a joint axis between a primary joint assembly end and a secondary joint assembly end and comprises a housing including a first housing part and a second housing part, and an output part arranged at the secondary joint assembly end. The joint assembly also comprises a motor and a strain wave gearing system. The first housing part comprises a plurality of first assembly holes arranged circumferentially around the joint axis and each of the plurality of first assembly holes extending parallel to the joint axis, and wherein the second housing part comprises a plurality of second assembly holes arranged circumferentially around the joint axis and each of the plurality of second assembly holes extending parallel to the joint axis. Each first assembly hole of the plurality of first assembly holes is aligned with a corresponding second assembly hole of the plurality of second assembly holes and is adapted to receive a primary fastening element being inserted parallel to the joint axis from the secondary joint assembly end towards the primary joint assembly end into the first assembly hole and the second assembly hole to mechanically fastening together the first housing part and the second housing part.

A wave gear device (1) is lubricated with non-hydrophobized powder (10A) enclosed in an internal space (9) before the end of running-in (aging), and the non-hydrophobized powder (10A) forms a firm lubricating film by transferring and adhering to each contact surface of the contact portions (B, C). During load running, the wave gear device (1) is lubricated with hydrophobized powder (10B) enclosed in the internal space (9) instead of the non-hydrophobized powder (10A). The powders (10A, 10B) used are powders of ionic crystal compounds (MoS2, WS2, etc.) having a layered crystal structure. By lubricating the wave gear device (1) during load running with the hydrophobized powder (10B), temporary efficiency reduction at the start of running can be suppressed, and stable running of the wave gear device (1) can be maintained.

Regarding the three-dimensional tooth profile of the internal teeth (20) of the harmonic gear device (1), at the outer end (20a) of the internal teeth, it is the basic internal tooth profile (20(0)), and at other positions in the tooth trace direction, it is a reduced tooth profile obtained by reducing the basic internal tooth profile (20(0)) proportionally only in the lateral direction at a ratio proportional to the distance from the outer end (20a) of the internal teeth. Regarding the three-dimensional tooth profile of the external teeth (3), at the position of the outer end (30a) of the external teeth, it is the basic external tooth profile (30(0)), and at other positions in the tooth trace direction, it is an enlarged tooth profile obtained by enlarging the basic external tooth profile (30(0)) proportionally only in the lateral direction at a ratio proportional to the distance from the outer end (30a) of the external teeth. Compared with the case where only the external teeth (30) are formed into a three-dimensional tooth profile, the gear cutting process becomes easier. In addition, since the tooth profile is obtained by reducing and enlarging proportionally only in the lateral direction in the tooth trace direction, the gear cutting process becomes even easier.

This cup-shaped strain wave gearing (1) comprises a rigid internally toothed gear (2), a cup-shaped flexible externally toothed gear (3), a wave generator (4), an output member (5) to which output rotation is transmitted from the externally toothed gear (3), a cross roller bearing (6) that supports the externally toothed gear (3) so as to be capable of rotating relative to the internally toothed gear (2), and a device hollow portion (7) that extends through a device center portion in the direction of the device axis (1a). An annular boss (33) defining a cup bottom surface portion of the externally toothed gear (3) is coaxially connected to the output member (5) via an intermediate member (8). It is possible to realize a strain wave gearing with which the hollow diameter of the device hollow portion (7) can be increased and connection torque between the externally toothed gear (3) and the output member (5) can be ensured without deforming the output member (5).