Feed rate and positioning control system for a machine tool

Claim 2

In a machine tool, a rotatable pulse motor, means for applying first pulses to said pulse motor to effect rotation thereof, means responsive to rotation of said pulse motor for developing second pulse, and means responsive to said first and second pulses for developing an emergency signal whenever said pulse motor lags a predetermined amount.

Claim 3

In a machine tool, a rotatable pulse motor, means for applying first pulses to said pulse motor to effect rotation thereof, means responsive to rotation of said pulse motor for developing second pulse, and means responsive to said first and second pulses for developing an emergency signal whenever said pulse motor lags a predetermined amount.

Claim 4

In a machine tool, a rotatable pulse motor, means for applying first pulses to said pulse motor to effect rotation thereof, means responsive to rotation of said pulse motor for developing second pulse, and means responsive to said first and second pulses for developing an emergency signal whenever said pulse motor lags a predetermined amount.

Claim 5

The machine tool according to claim 1 including a machine element operatively arranged to be advanced by said pulse motor, and means responsive to said emergency signal for retracting said machine element upon the occurrence of said emergency signal.

Claim 6

In a machine tool including workpiece and tool supports and pulse driven means for effecting relative movement between such supports, in combination: variable pulse rate generating means for driving said pulse driven means; pulse counting means for counting the number of pulses supplied by said pulse generating means to said pulse driven means; a plurality of pulse rate control means for selectively controlling the pulse rate output of said pulse generating means; a plurality of end point switch means for producing different digital number outputs corresponding to different relative positions between said workpiece and tool supports; comparator means for comparing the number output of selected end point switch means and the output of said pulse counting means periodically to produce an advance signal; sequence control means responsive to an advance signal for sequentially enabling different ones of said end point switch means and different ones of said pulse rate control means whereby to initiate progressive steps of relative movements between said supports.

Claim 7

In a machine tool including workpiece and tool supports and pulse driven means for effecting relative movement between such supports, in combination: variable pulse rate generating means for driving said pulse driven means; pulse counting means for counting the number of pulses supplied by said pulse generating means to said pulse driven means; a plurality of pulse rate control means for selectively controlling the pulse rate output of said pulse generating means; a plurality of end point switch means for producing different digital number outputs corresponding to different relative positions between said workpiece and tool supports; comparator means for comparing the number output of selected end point switch means and the output of said pulse counting means periodically to produce an advance signal; sequence control means responsive to an advance signal for sequentially enabling different ones of said end point switch means and different ones of said pulse rate control means whereby to initiate progressive steps of relative movements between said supports.

Claim 8

In a machine tool including workpiece and tool supports and pulse driven means for effecting relative movement between such supports, in combination: variable pulse rate generating means for driving said pulse driven means; means for effecting reverse drive to said pulse driven means at the end of a machining operation to position said supports in predetermined starting position; pulse counting means for counting the number of pulses supplied by said pulse generating means to said pulse driven means during operation of the latter in forward direction commencing from said starting position of relative movement between said supports; a plurality of manually set end point switch means for producing digital number outputs corresponding to different relative positions between said supports which are between said starting position and that position attained at the end of a machining operation; comparator means for comparing the number output of a selected end point switch means and the output of said pulse counting means and at coincidence therebetween to produce an advance signal; sequence control means responsive to each advance signal for producing an enabling signal sequentially enabling different ones of said end point switch means whereby to initiate progressive steps of relative movEments between said supports at said different relative positions to which said end points switch means are set; caliper means for measuring the size of a workpiece as it is being machined and having an output connected to said sequence control means for producing other enabling signals initiating other progressive steps of relative movements between said supports; and means responsive to said enabling signals for selectively controlling the rate output of said pulse generating means.

Claim 9

In a machine tool including workpiece and tool supports and pulse driven means for effecting relative movement between such supports, in combination: variable pulse rate generating means for driving said pulse driven means; means for effecting reverse drive to said pulse driven means at the end of a machining operation to position said supports in predetermined starting position; pulse counting means for counting the number of pulses supplied by said pulse generating means to said pulse driven means during operation of the latter in forward direction commencing from said starting position of relative movement between said supports; a plurality of manually set end point switch means for producing digital number outputs corresponding to different relative positions between said supports which are between said starting position and that position attained at the end of a machining operation; comparator means for comparing the number output of a selected end point switch means and the output of said pulse counting means and at coincidence therebetween to produce an advance signal; sequence control means responsive to each advance signal for producing an enabling signal sequentially enabling different ones of said end point switch means whereby to initiate progressive steps of relative movEments between said supports at said different relative positions to which said end points switch means are set; caliper means for measuring the size of a workpiece as it is being machined and having an output connected to said sequence control means for producing other enabling signals initiating other progressive steps of relative movements between said supports; and means responsive to said enabling signals for selectively controlling the rate output of said pulse generating means.

Claim 10

In a machine tool including workpiece and tool supports and pulse driven means for effecting relative movement between such supports, a tool carried by said tool support, in combination: variable rate pulse generating means for driving said pulse driven means in forward and reverse directions respectively to advance and to retract said supports; means for causing said pulse generating means to retract said supports a predetermined distance to a starting position in response to attainment of a predetermined advance position thereof corresponding to a position at which machining of a workpiece is terminated; rate control means for selectively adjusting the pulse rate output of said pulse generating means; sequence control means responsive to advance signals corresponding to attainment of different positions between said starting position and said position at which machining is terminated for actuating said rate control means to effect progressive advance movements of different rates; transducer means for producing an advance signal in response to contact between the tool and a workpiece whereby to actuate said sequence control means; manually set end point switch means for producing different digital number outputs corresponding to different relative positions of said supports; pulse counting means for counting pulses supplied by said pulse generating means commencing from said starting position; comparator means for comparing the number output of selected end point switch means and the output of said pulse counting means periodically to produce an advance signal whereby to actuate said sequence control means; and caliper means for measuring the size of a workpiece to produce comparison numbers to provide at least a further advance signal to actuate said sequence control means and a signal for actuating said means for causing said pulse generating means to retract said supports.

Claim 11

In a machine tool including workpiece and tool supports and pulse driven means for effecting relative movement between such supports, a tool carried by said tool support, in combination: variable rate pulse generating means for driving said pulse driven means in forward and reverse directions respectively to advance and to retract said supports; means for causing said pulse generating means to retract said supports a predetermined distance to a starting position in response to attainment of a predetermined advance position thereof corresponding to a position at which machining of a workpiece is terminated; rate control means for selectively adjusting the pulse rate output of said pulse generating means; sequence control means responsive to advance signals corresponding to attainment of different positions between said starting position and said position at which machining is terminated for actuating said rate control means to effect progressive advance movements of different rates; transducer means for producing an advance signal in response to contact between the tool and a workpiece whereby to actuate said sequence control means; manually set end point switch means for producing different digital number outputs corresponding to different relative positions of said supports; pulse counting means for counting pulses supplied by said pulse generating means commencing from said starting position; comparator means for comparing the number output of selected end point switch means and the output of said pulse counting means periodically to produce an advance signal whereby to actuate said sequence control means; and caliper means for measuring the size of a workpiece to produce comparison numbers to provide at least a further advance signal to actuate said sequence control means and a signal for actuating said means for causing said pulse generating means to retract said supports.

Claim 12

In a machine tool as defined in claim 5 including a second pulse generating means actuated by said pulse driven means for producing a pulse output in accord with movement produced by said pulse driven means; counter means driven in opposite senses respectively by the output of the first pulse generating means and by the output of said second pulse generating means; and means responsive to output of said counter means indicative of predetermined lag of said pulse driven means for effecting emergency retractions between said supports.

Claim 13

In a machine tool as defined in claim 4 including a second pulse generating means actuated by said pulse driven means for producing a pulse output in accord with movement produced by said pulse driven means; counter means driven in opposite senses respectively by the output of the first pulse generating means and by the output of said second pulse generating means; and means responsive to output of said counter means indicative of predetermined lag of said pulse driven means for effecting emergency retractions between said supports.

Claim 14

In a machine tool as defined in claim 3 including a second pulse generating means actuated by said pulse driven means for producing a pulse output in accord with movement produced by said pulse driven means: counter means driven in opposite senses respectively by the output of the first pulse generating means and by the output of said second pulse generating means; and means responsive to output of said counter means indicative of predetermined lag of said pulse driven means for effectinG emergency retractions between said supports.

Claim 15

In a machine tool as defined in claim 3 wherein said pulse generating means includes an oscillator and means for providing signals at fixed frequencies related to the frequency of the oscillator; means for causing dwell between at least some progressive steps of relative movement between said supports and comprising a pulse counter connected to one of the fixed frequency outputs of said pulse generating means, a comparator, and manually set means for producing a selected digital number output, said comparator being connected to said pulse counter and said manually set means to produce an advance signal upon match therebetween.

Claim 16

In a machine tool as defined in claim 4 wherein said pulse generating means includes an oscillator and means for providing signals at fixed frequencies related to the frequency of the oscillator; means for causing dwell between at least some progressive steps of relative movement between said supports and comprising a pulse counter connected to one of the fixed frequency outputs of said pulse generating means, a comparator, and manually set means for producing a selected digital number output, said comparator being connected to said pulse counter and said manually set means to produce an advance signal upon match therebetween.

Claim 17

In a machine tool as defined in claim 5 wherein said pulse generating means includes an oscillator and means for providing signals at fixed frequencies related to the frequency of the oscillator; means for causing dwell between at least some progressive steps of relative movement between said supports and comprising a pulse counter connected to one of the fixed frequency outputs of said pulse generating means, a comparator, and manually set means for producing a selected digital number output, said comparator being connected to said pulse counter and said manually set means to produce an advance signal upon match therebetween.

Claim 18

In a machine tool as defined in claim 3 including a grinding wheel carried by said tool support.

Claim 19

In a machine tool as defined in claim 4 including a grinding wheel carried by said tool support.