초록 ▼

A drive mechanism for a machine such as a machine tool or robot includes a rotatable shaft, e.g. a lead screw or spindle, drivingly connected with a movable element, e.g. a worktable or tool support, in the machine, a drive shaft for rotation by a motor and a coupling unit, e.g. clutch or gear trans

A drive mechanism for a machine such as a machine tool or robot includes a rotatable shaft, e.g. a lead screw or spindle, drivingly connected with a movable element, e.g. a worktable or tool support, in the machine, a drive shaft for rotation by a motor and a coupling unit, e.g. clutch or gear transmission, for drivingly connecting the drive shaft with the rotatable shaft to move the movable element in a predetermined form of movement under a variable load in the machine. Encoders are provided in a rotation-sensing relationship with the drive shaft and the rotatable shaft, respectively, to feed two trains of rotation-responsive pulses into a differential counter which provides a difference in angle of rotation signal representing an instantaneous torque produced at the drive coupling unit between the drive and rotatable shafts. The differential signal and a preset signal set in a setting circuit, representing a predetermined value of torque are processed in an output circuit which produces a control signal which is used to control the motor or the coupling unit so as to maintain the torque between the drive and rotatable shafts substantially at the reference value.

대표청구항 ▼

A drive mechanism for a machine, comprising: rotatable shaft means drivingly connected with a movable element in the machine; drive shaft means for rotation by motor means; coupling means for drivingly connecting said drive shaft means with said rotatable shaft means to move said movable element in

A drive mechanism for a machine, comprising: rotatable shaft means drivingly connected with a movable element in the machine; drive shaft means for rotation by motor means; coupling means for drivingly connecting said drive shaft means with said rotatable shaft means to move said movable element in a predetermined form of movement under a variable load in the machine; first sensing means responsive to the rotation of said drive shaft means to produce a first sensing signal; second sensing means responsive to the rotation of said rotatable shaft means to produce a second sensing signal; comparison means responsive to said first and second sensing signals to produce a comparison signal representing a torque produced at said coupling means between said drive and rotatable shaft means while said element is moved in said form of movement by said motor means; and output means responsive to said comparison signal and to a reference signal representing a predetermined reference value of torque to produce an output signal, said output means comprising control means connected to an energization circuit for said motor for controlling the rotation of said drive shaft means thereby with said output signal so as to maintain said detected torque at said coupling means substantially at said reference value.