No-load torque compensation system and the application thereof in adaptive control

Claim 3

Apparatus for controlling the torque of a motor at its load as to compensate for load-independent torque losses comprising: a. a torque transducer for monitoring the motor armature current both under no-load conditions to produce a first analog signal and subsequently under load conditions to produce a third analog signal; b. storage means connected to said transducer for storing the first analog signal for use after no-load operation has ceased; c. input means for providing a second analog signal representing a desired torque at the load under load conditions; d. means connected to said transducer, said storage means and said input means for combining said first, second and third analog signals while the motor is operating under load conditions to establish the deviation between the actual and the desired torque at the load under existing conditions; and e. means responsive to the output of said combining means for adjusting the load on the motor to bring the actual torque into correspondence with the desired torque during cutting operation.

Claim 4

Apparatus for controlling the torque of a motor at its load as to compensate for load-independent torque losses comprising: a. a torque transducer for monitoring the motor armature current both under no-load conditions to produce a first analog signal and subsequently under load conditions to produce a third analog signal; b. storage means connected to said transducer for storing the first analog signal for use after no-load operation has ceased; c. input means for providing a second analog signal representing a desired torque at the load under load conditions; d. means connected to said transducer, said storage means and said input means for combining said first, second and third analog signals while the motor is operating under load conditions to establish the deviation between the actual and the desired torque at the load under existing conditions; and e. means responsive to the output of said combining means for adjusting the load on the motor to bring the actual torque into correspondence with the desired torque during cutting operation.

Claim 5

Apparatus for controlling the torque of a motor at the cutting head of a material cutting machine including compensation for the no-load torque losses of the motor, said apparatus comprising: a. a torque transducer for monitoring the motor armature current under no-load conditions and subsequently during cutting operations to produce first and third analog signals respectively; b. storage means selectively connected to said transducer for storing the first analog signal for use during a subsequent cutting operation; c. input means for selectively providing a second analog signal representing a desired cutting torque; d. means selectively connected to said transducer, said storage means and said input means during cutting operations for combining said first, second and third analog signals to establish the deviation between the actual and the desired cutting torque; and e. means responsive to the output of said combining means for adjusting the cutting load to bring the actual torque into correspondence with the desired torque.

Claim 6

Apparatus for controlling the torque of a motor at the cutting head of a material cutting machine including compensation for the no-load torque losses of the motor, said apparatus comprising: a. a torque transducer for monitoring the motor armature current under no-load conditions and subsequently during cutting operations to produce first and third analog signals respectively; b. storage means selectively connected to said transducer for storing the first analog signal for use during a subsequent cutting operation; c. input means for selectively providing a second analog signal representing a desired cutting torque; d. means selectively connected to said transducer, said storage means and said input means during cutting operations for combining said first, second and third analog signals to establish the deviation between the actual and the desired cutting torque; and e. means responsive to the output of said combining means for adjusting the cutting load to bring the actual torque into correspondence with the desired torque.

Claim 7

Apparatus as recited in claim 3 wherein said storage means further comprises: a. a reversible digital counter; b. means connected to said transducer for converting the first analog signal to a digital form signal for storage in said counter; and c. means connected between the output of said counter and said combining means for converting the digital form signal back to analog form before it is applied to said combining means.

Claim 8

Apparatus as recited in claim 3 further including means for disconnecting said storage means and said input means from said combining means during no-load motor operation and for closing said connection while disconnecting said storage means from said transducer during operation under load, whereby the stored first analog signal can be updated only during the no-load periods of operation preceding each period of cutting operation.