Abstract: A strain wave gearing has a wave generator provided with a plurality of rollers mounted between an ellipsoidal outer peripheral surface of a plug and an inner peripheral surface of an externally toothed gear. The plug is formed with recesses along the ellipsoidal outer peripheral surface. The recesses open in a first end surface of the plug facing toward a diaphragm of the externally toothed gear. The radial rigidity of the plug is relatively low in the side having the first end surface in the direction of a plug axis. When viewed along the direction of the plug axis, the respective rollers can be brought into linear contact with the inner peripheral surface of the externally toothed gear at positions on the long axis (Lmax) of the elliptically-flexed externally toothed gear, so as not to occur one-sided contact state.

Abstract: A compact harmonic drive system with a motor residing within the flexspline cup. The motor may reside further into the flexspline cup than the wave generator, and the air gap of the motor may be further out radially than the interior of the wave generator bearing. The motor may use an outrunner configuration with an outboard rotor made up of magnets, allowing for a large radial distance to the air gap and resulting in higher torque. The interior stator windings are thermally well coupled to the drive system structure. The harmonic drive may be coupled to a deployment system adapted to support moment loads perpendicular to the rotation axis such that those loads are not supported by the harmonic drive.

Abstract: The present disclosure relates to a frictional wave reducer mainly used for industrial robot joints and having an operating principle modified from that of a conventional strain wave gearing, which includes a wave generator having a conic pressurizing face on the outermost side, a toothless flex spline having a conic friction tube in which the wave generator is accommodated with the conic pressurizing face inscribed in the conic friction tube, and a toothless circular spline accommodating the toothless flex spline and having an internal conic friction face in which the conic friction tube is inscribed at a plurality of axially symmetrical points to form an internal friction wheel with the toothless flex spline. Accordingly, disadvantages of the conventional strain wave gearing are overcome to provide a reducer having high productivity and high rotation accuracy without generation of vibration and noise.

Abstract: A harmonic drive includes an internally toothed housing element (2), a pot-shaped output element (4) which is mounted in the housing element (2), and a likewise pot-shaped, resilient drive element (19) which is connected to the output element (4) and has an external toothing system (13) which meshes with the internal toothing system (14) of the housing element (2). A spring element (35) is active between the housing element (2) and the output element (4), which spring element (35) is arranged in an annular chamber which is delimited radially to the inside by a sleeve section (24) of the resilient drive element (19), radially to the outside by a cylindrical section (5) of the output element (4), and in the axial direction firstly by an annular disc-shaped surface (23) of the housing element (2) and secondly by a bottom (9) of the output element (4).

Abstract: An inspection robot may include an inspection chassis and a drive module with magnetic wheels coupled to the inspection chassis. The drive module may further include a motor and a gear box located between the motor and a magnetic wheels. The gear box may include a flex spline cup which interacts with the ring gear. The inspection robot may further include a magnetic shielding assembly to shield the motor and an associated electromagnetic sensor from electromagnetic interference generated by the magnetic wheels.

Abstract: Harmonic drives are used widely in robotics as a method for achieving high gear reductions and for driving force transmissions. The harmonic drive is made a three components: a wave generator, a flexspline, and a circular spline. Embodiments described flexsplines for a metal strain wave gearing. The cup of the flexspline is free from sharp edges and with a rounded bottom with a curvature maximized based on the geometry of the flexspline. Compared to a steel flexspline, implementations of flexsplines will have the same outer diameter, the same number of teeth and profile, the same input shaft/base, the same wall thickness near the teeth, but comprise a rounded bottom where the input shaft/base transitions to the straight wall of the flexspline, providing improved performance of BMG flexsplines by reducing low cycle fatigue failures due to stress concentrations.

Abstract: 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).

Abstract: The present invention discloses a shafting structure of an integrated joint for a collaborative robot, wherein two ends of a long input shaft are respectively a motor rear end and a flexspline end, and a harmonic gear drive is installed on the flexspline end; the motor rear end is coaxially provided with a motor rear end bearing set, a motor rear end inner race pressing ring, a motor rear end outer race pressing ring, a motor rear end outer race seat and a motor rear end angle encoder mounting seat; and the flexspline end is provided coaxially with a flexspline end bearing set, a flexspline end inner race pressing ring and the harmonic gear drive. In the present invention high-precision position feedback and control can be realized.

Abstract: A linear actuator comprises a motor for producing a bi-directional rotational output. A casing is connected to the motor at a proximal end, the casing having an inner cavity defining a joint surface. A shaft is within the inner cavity of the casing and actuated by the motor for rotation. A sliding tube is at least partially in the inner cavity of the casing for moving in translation in an axial direction relative to the casing. One or more travelling nut is connected to the sliding tube assembly for moving with the sliding tube in the axial direction, the travelling nut being operatively engaged to the shaft for converting a rotational motion of the shaft into a translation of the sliding tube. A liner is between the sliding tube and the joint surface of the inner cavity, an inner surface of the liner defining longitudinal contact surfaces separated by longitudinal grooves, the longitudinal contact surfaces contacting the sliding tube.

Abstract: A gear device includes an internal gear, an external gear having flexibility, a wave generator, a cross roller bearing, and a first seal and a second seal. The external gear includes a cylindrical body section including a first end portion, with which the wave generator is in contact, and a second end portion on the opposite side of the first end portion, external teeth provided on the outer circumferential surface of the first end portion, an annular diaphragm section provided on the outer side of the second end portion, and a boss section provided on the outer side of the diaphragm section. The first seal is sandwiched between the boss section and an outer ring of the cross roller bearing. The second seal includes a proximal end fixed to the outer ring and a distal end in contact with the outer circumferential surface of an inner ring.

Abstract: Provided is a double-flexspline harmonic reducer, comprising a strong flexspline (3), a weak flexspline (2) and a wave generator (1). The strong flexspline (3) and the weak flexspline (2) are coaxially fixed in an axial direction and a radial direction, and teeth which can be engaged with each other and are different in the number thereof are provided on the strong flexspline (3) and the weak flexspline (2) respectively. The wave generator (1) causes the weak flexspline (2) to undergo non-circular elastic deformation and then to partially engage with the strong flexspline (3), and a contact portion of the strong flexspline (3) and the weak flexspline (2) undergoes non-circular elastic deformation under a radial pressure from the weak flexspline (2). A wall thickness of the strong flexspline (3) is greater than or equal to 2 times and less than 5 times that of the weak flexspline (2).

Abstract: A bending meshing type gear device includes a wave generator, an external gear that is bent and deformed by the wave generator, an internal gear that meshes with the external gear, and a wave generator bearing disposed between the wave generator and the external gear, in which an inner ring rolling surface on which a rolling element of the wave generator bearing rolls includes a hardened layer, and the hardened layer has a characteristic that a surface hardness after operating for a predetermined time is increased compared to a surface hardness before operation.

Abstract: An externally toothed gear of a cup-type strain wave gearing has external teeth, the tooth profile of which gradually changes in the tooth-trace direction. The external teeth are formed with an external teeth portion capable of meshing with internal teeth of an internally toothed gear, a first external teeth extension portion and a second external teeth extension portion, in which the first and second external teeth extension portions do not mesh with the internal teeth. The second external teeth extension portion has a narrowing tapered tooth profile so that the second external teeth extension portion serves as a guide when the external teeth is inserted into the internal teeth. The work of assembling the externally toothed gear in the internally toothed gear is made easier.

Abstract: This gear wheel mechanism includes a rotator, a first gear wheel, a second gear wheel, and a reinforcement member. The rotator is configured to be rotatable about a rotation shaft and has an elliptical shape as viewed in an axis direction of the rotation shaft. The first gear wheel includes a first base portion including a first outer circumferential surface and a first inner circumferential surface and having a hollow cylindrical shape configured to be deformable by the rotator being inserted in the axis direction of the rotation shaft and external teeth formed in the outer circumferential surface.

Abstract: A harmonic drive system for a pedal-electric-cycle comprises a transmission gear device including a wave generator assembled by an elliptical cam and a flexible bearing, a flexible-flexspline, a rigid-circular-spline having rigid-circular-spline internal gear teeth, a gear set, and a one-way clutch having an inner surface defining a space for containing a spindle of the pedal-electric-cycle. A first end of the flexible-flexspline has flexible-flexspline external gear teeth for meshing with the rigid-circular-spline internal gear teeth and an inner surface defining a space for containing the wave generator. The gear set has a first input portion connected to a second end of the flexible-flexspline, a second input portion having an inner surface defining a space for containing the one-way clutch, and an output portion connected to a sprocket of the pedal-electric-cycle. The first input portion has a first-input rotational axis. The second input portion has a second-input rotational axis.

Abstract: A joint shaft structure includes: a base member; an output shaft member supported on one side of the base member so as to be rotatable; and a strain wave gear reducer rotating the shaft member relative to the base member by transmitting rotation of a motor to the shaft member while reducing the speed of the rotation. The reducer includes: a wave generator fixed to a shaft rotated by a driving force from the motor; a flexspline having, at one end, an elastic part which includes a plurality of external teeth and inside which the generator is fitted; and a ring gear disposed on a radially outer side of the flexspline and fixed to the shaft member, and having internal teeth meshing with the external teeth. The flexspline is fixed to the base member at the other end disposed farther on the base member side than the elastic part.

Abstract: 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.

Abstract: A transportation tooling structure, a split electric motor module with the transportation tooling structure, and a transportation method are provided. The transportation tooling structure comprises: a split base plate, a stator support and a rotor support, wherein the lower end of the stator support is fixedly supported on the upper surface of the split base plate, and the upper end of the stator support is fixedly supported on the side of a split stator close to the split base plate; and the upper end of the rotor support is fixedly supported on the side of an end of a split rotor away from the split stator, and the lower end of the rotor support is fixedly supported on the side of the split stator away from the split base plate.

Abstract: Methods and apparatus that can include a rotatable target to generate a sinusoidal signal in a magnetic field sensor, wherein the target includes a plurality of sinusoidal teeth to reduce angular error. A magnetic field sensor can be configured to determine a position of the target. In embodiments, a rotatable target to generate a sinusoidal signal in a magnetic field sensor can include a plurality of sinusoidal teeth and a number of harmonics to reduce angular error.

Abstract: Harmonic drives (HDs) are used widely in robotics as a method for achieving high gear reductions and for driving force transmissions. The HD is made a three components: a wave generator, a flexspline, and a circular spline. Low-cost wave generators for metal strain wave gearing are provided. Wave generators are provided that incorporate commercially available bearings that form an ellipse either statically or through adjustment. Wave generators are optimized to maximum performance, including increasing the efficiency and the lifetime, while maximizing the running torque. The shape, size, number, type and location of the bearings can be changed so that the wave generator fails at a similar lifetime as a low cost flexspline. The shape of the wave generator may be adjusted to change the performance of the strain wave gear. The combination of low-cost flexsplines with low-cost wave generators reduces the cost of the strain wave gear.

Abstract: A gear device includes an internal gear, an external gear, and a wave generator. The external gear includes a cylinder section including external teeth, a diaphragm extending to a radial direction outer side of the cylinder section on the opposite side of the external teeth, and an annular boss section coupled to the outer circumferential end side of the diaphragm. The thickness of the diaphragm gradually decreases from the outer circumferential end toward a center portion in the radial direction of the diaphragm. In a natural state, a part (an inclination start part) where a first surface on the external teeth side of the diaphragm starts to incline with respect to an imaginary surface, which is a surface perpendicular to a rotation axis, is present further on the cylinder section side in the radial direction than the inner circumferential surface of the boss section.

Abstract: A coaxial gear (1), includes an axially oriented tooth system (5) with respect to a rotational axis (3) of the coaxial gear (1), a tooth carrier (7) having axially oriented guideways (9), tooth pins (11) received within the guideways (9) for engaging with the tooth system (5), wherein the tooth pins (11) are axially oriented within the guideways (9) by their respective longitudinal axes and are mounted within the guideways (9) in an axially displaceable manner, and a cam disc (15) rotatable about the rotational axis (3) for axially driving the tooth pins (11), wherein a plurality of bearing segments (17) is disposed between the cam disc (15) and the tooth pins (11) for bearing the tooth pins (11), and wherein, on a side facing the tooth pins, the bearing segments (17) have an elevation at least in sections formed as a spherical cap for bearing the respective tooth pin (11).

Abstract: A speed ratio switching type strain wave gearing can switch the speed ratio of output rotation with respect to one input rotation into two states or multiple states with a simple configuration. The speed ratio switching type strain wave gearing includes first and second internally tooted gears, an externally toothed gear having first and second external teeth formed on the external peripheral surface thereof, a wave generator that causes the first and second external teeth to partially mesh with the first and second internally toothed gears, a clutch mechanism that can selectively switch the first and second internally toothed gears into a fixed state. Input rotation from the wave generator can be reduced in speed at a different speed ratio and derived from the externally toothed gear by selectively switching the first and second internally toothed gears into a fixed state.

Abstract: Disclosed herein is a wave generator for a reducer of a harmonic drive structure. The reducer of a harmonic drive structure includes: a circular spline of a ring shape; a flex spline mounted inside the circular spline and having teeth engaged with teeth formed at three or more positions of the inner circumferential surface of the circular spline to be rotated; and a wave generator mounted inside the flex spline, and including a cam plate of a circular shape, and three or more protrusions formed at three or more positions of the outer circumferential surface of the circular cam plate so that the protrusions formed on the outer circumferential surface of the cam plate elastically deform the three or more positions inside the flex spline.

Abstract: A harmonic speed reducer is provided. The harmonic speed reducer includes a wave generator, a flexible gear, a first rigid gear, and a second rigid gear. The wave generator can be driven to rotate relative to a central axis. The flexible gear has a plurality of first outer gear structures, a division groove, and a plurality of second outer gear structures. The first rigid gear has a plurality of first inner gear structures configured to be engaged with the first outer gear structures. The second rigid gear has a plurality of second inner gear structures configured to be engaged with the second outer gear structures. A first intersection line is defined between each of the first inner gear structures and a sectional surface. An angle between the first intersection line and a first horizontal line is within a range from 0.1 degrees to 5 degrees.

Abstract: A unit-type strain wave gearing device provided with a cross roller bearing that supports an internally toothed gear and an externally toothed gear in a state in which both gears can rotate relative to each other, and a meshing section of both gears is lubricated with grease. A gap by which the meshing section and the cross roller bearing raceway groove communicate is formed between the inner ring of the cross roller bearing and the external gear. Due to the pump effect caused by deflection of the external gear, grease is pushed from the meshing section to the gap. Some grease is returned to the inner space of the externally toothed gear via a grease-flowing hole that penetrates the diaphragm of the external gear. Thus, leakage of grease from an oil seal of the cross roller bearing to the unit side can be controlled.

Abstract: Disclosed is a triple harmonic speed reducer, which enables a flexible inner gear to generate three tooth misalignment motions after a wave generator rotates for one circle, so that the harmonic speed reducer has higher position precision and rotation precision, more stable transmission, and more stable operation. The triple harmonic speed reducer includes a wave generator, a flexspline and a rigid circular spline, wherein the flexspline includes a flexible inner gear and an output part, the wave generator is arranged in an inner installation cavity of the flexible inner gear, the wave generator includes an input shaft end and a cam, wherein a flexible bearing is annularly arranged between an outer ring peripheral surface of the cam and an inner ring peripheral surface of the flexible inner gear, the cam of the wave generator is specifically of a three-convex structure.

Abstract: A gearing includes an internal gear, a flexible external gear partially meshing with the internal gear and relatively rotating about a rotation axis to the internal gear, and a wave generator provided inside of the external gear and moving a mesh position between the internal gear and the external gear in a circumferential direction about the rotation axis, wherein the external gear includes an external tooth having an external tooth surface, the external tooth surface has an external tooth convex pattern including a first convex portion and a second convex portion extending in directions crossing directions of a tooth trace of the external tooth and arranged adjacent to each other in the directions of the tooth trace, and a distance between the first convex portion and the second convex portion is from 80 ?m to 520 ?m.

Abstract: A speed reducer includes a reduction mechanism, which includes an internal gear and an external gear meshing with the internal gear, and a first member, and transmits rotating motion decelerated by the reduction mechanism to a driven member. The speed reducer includes a protection member disposed between the first member and the driven member. The first member is formed of a material having specific gravity lower than at least one of the internal gear and the external gear and hardness lower than the driven member. The protection member is formed of a material having hardness higher than the first member.

Abstract: In a wave generator for a strain wave gearing, a plug outer peripheral surface of a rigid wave plug has a non-circular profile and is fixed to an inner-race inner peripheral surface of a wave bearing by press-fitting and using an adhesive. The plug outer peripheral surface is a groove formation surface in which microgrooves are formed as adhesive-retaining grooves that can retain the adhesive. When the wave plug is press-fitted into the wave bearing, the amount of adhesive that is scraped out from therebetween is reduced and the bonding strength therebetween can be increased while also preventing unevenness of the bonding strength.

Abstract: In a rotation transmission mechanism that transmits the rotational driving force of a motor to a load-side member via a speed reducer, a strain wave gearing is used as the speed reducer, and the allowable load torque of members in the powertrain other than the strain wave gearing is greater than a predetermined upper-limit load torque. The allowable load torque of the strain wave gearing is dictated by the ratcheting torque, which is set so as not to exceed the upper-limit load torque. In an overload state, ratcheting is generated in the strain wave gearing, so that the strain wave gearing functions as a mechanical fuse. Other power transmission members can be protected from an overload state without adding a separate member such as a torque limiter.

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

Abstract: A method for selecting a gear in the transmission of a power tool having an electric motor. The method includes the following steps of changing an operating device from a first position to a second position in order to select a gear in the transmission; detecting a signal via at least one sensor corresponding to the second position of the operating device; sending the signal to a controller; changing the rotational speed of the electric motor from a first value to a second value via the controller; changing the operating device from the second position to a third position; changing the stepping motor from a first position to a second position corresponding to the third position of the operating device; and changing a shift fork from a first position to a second position in order to change from a first gear to a second gear.

Abstract: A gearing includes an internal gear, a flexible external gear partially meshing with the internal gear and relatively rotating about a rotation axis to the internal gear, and a wave generator including a bearing contacting an inner circumferential surface of the external gear and a cam contacting an inner circumferential surface of the bearing and moving a mesh position between the internal gear and the external gear in a circumferential direction about the rotation axis, wherein an outer circumferential surface of the bearing forms a circular shape without contact with the cam, the inner circumferential surface of the external gear forms a circular shape without contact with the wave generator, and d ? 1 2 - d ? 2 2 ? - 0.

Abstract: A gear device includes an internal gear, a flexible external gear, and a wave generator. The wave generator has an elliptic cam and a bearing. An inner ring has an inner ring raceway surface which a plurality of balls are in contact with, and a pair of inner ring shoulder parts. At a position of a minor axis, a first inner ring shoulder part has a greater height than a second inner ring shoulder part. At a position of a major axis, the second inner ring shoulder part has a greater height than the first inner ring shoulder part.

Abstract: A fluid rotary joint has a stator with a generally curved stator body and a flex spline with a flexible annular band disposed about and secured to the stator body. The stator also has at least three radially extendable members disposed between the stator body and the annular band to deform the annular band away from the stator body to contact the inner surface of a rotor. The inner circumference of the rotor is greater than the outer circumference of the annular band. A driver selectively expands the extendable members and brings the annular band of the stator into frictional driving engagement with the rotor for rotating the rotor. The extendable members may also be selectively extended to allow the stator and rotor to freely move with respect to one another or to have limited contact with one another to act as a torque limiting device.

Abstract: Disclosed is a compound harmonic gearbox having: a first ground gear and a second ground gear being interconnected about a stationary shaft to form a housing, wherein only the first ground gear includes gearbox mounting features; an output flange partially encased within the housing; a flex spline within the housing that drives the output flange; a wave generator within the housing that drives the flex spline; an input shaft with an input gear that drives the wave generator, the input shaft extending through the first ground gear, wherein the output flange is configured to rotate completely around the stationary shaft by rotating the input shaft.

Abstract: A gear mechanism is disclosed with a ring gear, with a flexible gear wheel arranged in the ring gear and with a wave generator which is in contact with the flexible gear wheel and which deforms the flexible gear wheel so that it is in sections in engagement in the ring gear. The gear mechanism can be configured in such a way that interference in the engagement in the gear teeth and the gear backlash are reduced, the noise behavior and the power transmission are improved and the service life is increased. The flexible gear wheel can include at least two flexible gear wheel disks arranged adjacent to one another in the axial direction, and each gear wheel disk can include at least two toothed segments in the circumferential direction which are connected to one another by way of spring segments.

Abstract: A method of machining a tooth flank of a gear with a gear machining tool. The method comprises rotating the tool and bringing the tool and the tooth flank into contact. Relative movements are provided between the tool and the gear to traverse the tool across the tooth flank along a path whereby the path produces a tooth flank geometry of a form which, when brought into mesh with a mating tooth flank under no load or light load to form a tooth pair, provides a motion graph curve comprising a sinusoidal portion (62, 89, 91, 90, 63) and a parabolic portion (92).

Abstract: An elastic gear wheel for a harmonic drive has a cylinder portion with tooth, and a flange which is integrally designed with the cylinder portion. The flange has recesses for fastening, and through-apertures for fastening.

Abstract: A gearing includes an internal gear, an external gear including external teeth placed around a rotation axis and meshing with the internal gear, a barrel part adjacent to the external teeth along the rotation axis, and an inner circumferential surface on an inner surface of the external teeth, and having flexibility and relatively rotating about the rotation axis to the internal gear, and a wave generator including a bearing having an outer ring in contact with the inner circumferential surface, an inner ring, and balls intervening between the outer ring and the inner ring, and moving a mesh position between the internal gear and the external gear about the rotation axis.

Abstract: A gear device includes an internal gear and an external gear that meshes with the internal gear, in which the internal gear is made of a resin, the external gear is made of a material having a smaller linear expansion coefficient than the resin, and PCDs of the internal gear and the external gear before use of the gear device are set such that lost motion becomes 0 min or more and 15 min or less due to a difference in a thermal expansion amount between the internal gear and the external gear at a time of use of the gear device.

Abstract: A roll stabilizer for a motor vehicle having a housing (137, 237) with a first stabilizer element (110, 210) coupled to the housing and an electric motor (150, 250) located in the housing (137, 237). The transmission (160, 260) is coupled to the electric motor (150, 250) on a drive side, and the output side of the transmission (160, 260) is coupled to a second stabilizer element (115, 215) such that the stabilizer elements are electromechanically rotatable with respect to one another. The electric motor is designed as a Vernier motor.

Abstract: A vehicle control surface, such as an aircraft horizontal stabilizer, is hydraulically controlled using solenoid operated valves (SOVs) controlling directional control valves and/or rate control valves with small numbers of ports, e.g. a four port three position directional control value and/or a four port two position rate control valve.

Abstract: 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.

Abstract: A strain wave gearing has a wave generator which flexes an externally toothed gear in a radial direction to form meshing portions thereof with an internally toothed gear in positions that are separated along a circumferential direction of the externally toothed gear. When the wave generator rotates, the meshing portions move in the circumferential direction. Non-meshing regions are formed in part of the meshing portions along the tooth trace direction thereof. The non-meshing regions are those of a prescribed width including the support center of a wave bearing in the tooth trace direction. The concentration of stress in the tooth root of the externally toothed gear can be alleviated, and the tooth-root fatigue strength of the externally toothed gear can be increased.

Abstract: A gas turbine engine includes a harmonic drive driven by an actuator, a drive shaft driven by the harmonic drive, the drive shaft with a first drive gear and a second drive gear. A first variable vane stage with a first actuator gear to direct drive one of a multiple of variable vanes, the first actuator gear meshed with the first drive gear; and a second variable vane stage with a second actuator gear to direct drive one of a multiple of variable vanes, the second actuator gear meshed with the second drive gear.

Abstract: A strain wave gearing wherein the outer circumferential surface of an outer ring of a wave generator is in contact with an inner-circumferential-surface portion of a flexible externally toothed gear, and a release groove, which is not in contact with the outer circumferential surface, is formed in the inner-circumferential-surface portion. The release groove is formed in a region containing a ball raceway groove. The groove depth of the release groove gradually increases from both sides of the groove in the groove width direction toward a deepest portion of the groove provided at an intermediate portion in the groove width direction. By providing the release groove, it is possible to smooth the distribution of pressing force of the wave generator acting on the externally toothed gear in the tooth-trace direction. In addition, the tooth root fatigue strength and the transmission torque capacity of the externally toothed gear can be improved.

Abstract: A harmonic pin ring gear system includes an input and output shaft and two outer gears, each with internal toothing, a single inner gear with external toothing arranged concentrically to a first outer gear and inside said first outer gear in axial direction, and a drive means extending between the two outer gears and the inner gear comprising a pin ring formed as one part in circumferential direction and a multiplicity of pins that protrude laterally in axial direction from the pin ring, a rotary transmitter for lifting the drive means off the external toothing of the inner gear and pressing the drive means into the internal toothing of the outer gear, wherein the input shaft is mounted on one side in the inner gear, the inner gear is mounted in an inner gear ball bearing, and the inner gear ball bearing is mounted in a housing cover.

Abstract: A harmonic drive is provided that comprises a wave generator, a flexible, externally toothed gear element that can be deformed by said wave generator, and at least one internally toothed gear component which meshes with the flexible, externally toothed gear element. The externally toothed element has, with respect to its mechanically unloaded state, a non-circular shape that deviates from an elliptical shape.