A method for operating a transmission device, in which a requested value of an output torque of the transmission device is input and a first control signal for controlling a first actuator and a second control signal for controlling a second actuator of the transmission device is determined according to the requested value. The control signals bring about input torques which, according to the requested value of the output torque, on the output side of the output shaft, cause moments with different signs and with different absolute values that are different from zero, or moments with the same signs and with the same absolute values that are different from zero.

A drive mechanism of a robot includes a first member, a second member which is supported by the first member and which is rotatable with respect to the first member about a vertical axis line, a main drive motor which is fixed to one of the first member and the second member, a main drive reducer which reduces rotation of the main drive motor and transmits the reduced rotation to the other one of the first member and the second member, and an auxiliary torque generator which constantly applies an unidirectional torque about an axis line A to the second member with respect to the first member.

Power is transmitted between the input shaft and the rotor shaft by the sun gear and the gear meshing. This eliminates the need for bearings to receive radial loads. Further, a thrust bearing disposed between the one axial end surface of the sun gear and the input shaft, and a second ball bearing abutting the other axial end surface of the sun gear are provided. This eliminates the need for a bearing for receiving a thrust load of the sun gear. A terminal block is arranged in a space opposite to the planetary gear device with respect to the electric motor caused by the reduction of the bearing. Therefore, it is possible to dispose the terminal block while suppressing or avoiding the increase in the size of the vehicle drive device.

Power is transmitted between the input shaft and the rotor shaft by the sun gear and the gear meshing. This eliminates the need for bearings to receive radial loads. Further, a thrust bearing disposed between the one axial end surface of the sun gear and the input shaft, and a second ball bearing abutting the other axial end surface of the sun gear are provided. This eliminates the need for a bearing for receiving a thrust load of the sun gear. A terminal block is arranged in a space opposite to the planetary gear device with respect to the electric motor caused by the reduction of the bearing. Therefore, it is possible to dispose the terminal block while suppressing or avoiding the increase in the size of the vehicle drive device.

A controlled or zero backlash gearmotor comprises a main gearmotor, a secondary service gearmotor, an electronic control unit and transmission and synchronization gears. The backslash control results from the cooperation between the main gearmotor, the secondary service gearmotor, and the electronic control unit which adjusts, based on parameters detected by a series of sensors, the load provided by the service gearmotor on one of two irreversible screws pressing on two worm screws, respectively, arranged at the side of a worm wheel. This latter supports a secondary shaft and is get into gear with both the worm screws, the two worm screws being synchronized by means of gears connecting them to each other so that a reversible motion transmission is executable.

In accordance with an example embodiment, a wrist includes a frame, ring gear rotatable about a ring axis, and motor assembly with a pinion subassembly and motor with an output shaft. The pinion subassembly includes an internal spline and pinion connected to opposite sides of an internal shaft and rotatable about a pinion axis, and motor and frame bolt patterns. The motor is fastenable to the pinion subassembly at a plurality of motor-pinion indices via the motor bolt pattern. The pinion subassembly is fastenable to the frame mount at a plurality of pinion-frame indices via the frame bolt pattern so as to mesh the pinion with the ring gear and allow the output shaft to drive the ring gear via the internal spline, internal shaft, and pinion. The distance between the ring axis and the pinion axis varies for the plurality of pinion-frame indices.

A method for operating a transmission device, in which a requested value of an output torque of the transmission device is input and a first control signal for controlling a first actuator and a second control signal for controlling a second actuator of the transmission device is determined according to the requested value. The control signals bring about input torques which, according to the requested value of the output torque, on the output side of the output shaft, cause moments with different signs and with different absolute values that are different from zero, or moments with the same signs and with the same absolute values that are different from zero.

In accordance with an example embodiment, a wrist includes a frame, ring gear rotatable about a ring axis, and motor assembly with a pinion subassembly and motor with an output shaft. The pinion subassembly includes an internal spline and pinion connected to opposite sides of an internal shaft and rotatable about a pinion axis, and motor and frame bolt patterns. The motor is fastenable to the pinion subassembly at a plurality of motor-pinion indices via the motor bolt pattern. The pinion subassembly is fastenable to the frame mount at a plurality of pinion-frame indices via the frame bolt pattern so as to mesh the pinion with the ring gear and allow the output shaft to drive the ring gear via the internal spline, internal shaft, and pinion. The distance between the ring axis and the pinion axis varies for the plurality of pinion-frame indices.

A worm backlash adjustment device includes a drive unit, a backlash adjustment unit, and a control device. The drive unit includes a first motor device, a first drive member, a linking member, a passive member, and a second drive member. The first drive member and the linking member are coaxially driven by the first motor device. The passive member is coaxially connected with the second drive member and linked by the linking member to turn reversely. The two drive members are disposed at two sides of a driven member to drive the driven member, respectively. The backlash adjustment unit includes a second motor device, a screw member, and a backlash adjustment member. Through the screw member, the backlash adjustment member is driven by the second motor device to move linearly. The second drive member has a drive function and a backlash adjustment function.

An anti-backlash gear control device is disclosed that includes a first bias module operable to generate a first bias to be applied to a first motor operable with a first gear, and a second bias module operable to generate a second bias, opposite the first bias, to be applied to a second motor operable with a second gear. The first gear and the second gear are operably connected to a load gear, such that rotation of at least one of the first gear and the second gear causes the load gear to move. Additionally, a command module can receive a drive command and output at least one of first and second command signals based on the drive command to be summed with the first and second biases, respectively, to generate first and second drive signals to operate the first and second motors to drive the first and second gears, respectively.