US3596266A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Numerical control system and method
Assignee: Houdaille Industries Inc
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Filing: 1968-07-12
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Granted: 1971-07-27
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Expires: 1988-07-12
Abstract
Abstract A control system having a stored program digital computer for transmitting commands to digital servos for a punch press with digital to analog converter circuitry providing for a digitally selected null zone, digital control of the slope of the analog error vs. count function for optimum slow down, and digital sensing of the null condition.
Inventors
- 👤 Kenneth Leonard Slawson
- 👤 Robert Joseph Kellner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:05
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/416; G05B19/19; G05B19/21; G05B19/23; G05B19/231; G05B2219/00; G05B2219/30; G05B2219/42; G05B2219/42213; G05B2219/43; G05B2219/43006; G05B2219/43115
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
350 words
A control system comprising: a source for supplying digital command signals representing a movement of a load with respect to X and Y-axes to a desired end point, X and Y-axis servo drives coupled to the load and responsive to respective X and Y-axis analog error signals for driving the load as a function of said analog error signals relative to the respective axes, a transducer coupled to each of said servo drives so as to be driven thereby as the load is moved relative to the corresponding axis and for generating motion pulses as a function of the movement of the load relative to the corresponding axis, a countercircuit for each axis connected with said source for registering the digital command signal for the axis and coupled with said transducer for the axis for receiving said motion pulses and operable to maintain an error count representing the displacement error of the load relative to the desired end point with respect to the axis, digital-analog circuitry for each axis connected with the corresponding countercircuit for providing an analog error signal in accordance with the magnitude of the error count in the corresponding countercircuit and connected with the corresponding servodrive for supplying said analog signal thereto for causing said servodrive to move the load toward the desired end point with respect to the axis, and a move-complete circuit for generating a move-complete signal, wherein the improvement comprises: said digital-analog circuitry including a digital null circuit for each axis connected with the countercircuit for the axis and with the move-complete circuit and operable for uniquely sensing error counts registered by the corresponding countercircuit which are within a predetermined null range of count values in the vicinity of 0 including a count value of 0 and including positive and minus count values immediately adjacent to the count value of 0, and responsive to error counts within said predetermined null range to establish a digitally determined null condition, said move-complete circuit being responsive to the existence of a null condition for each axis simultaneously for a predetermined time interval to generate said move-complete signal.
Claim 2
Dependent Claim
350 words
A control system comprising: a source for supplying digital command signals representing a movement of a load with respect to X and Y-axes to a desired end point, X and Y-axis servo drives coupled to the load and responsive to respective X and Y-axis analog error signals for driving the load as a function of said analog error signals relative to the respective axes, a transducer coupled to each of said servo drives so as to be driven thereby as the load is moved relative to the corresponding axis and for generating motion pulses as a function of the movement of the load relative to the corresponding axis, a countercircuit for each axis connected with said source for registering the digital command signal for the axis and coupled with said transducer for the axis for receiving said motion pulses and operable to maintain an error count representing the displacement error of the load relative to the desired end point with respect to the axis, digital-analog circuitry for each axis connected with the corresponding countercircuit for providing an analog error signal in accordance with the magnitude of the error count in the corresponding countercircuit and connected with the corresponding servodrive for supplying said analog signal thereto for causing said servodrive to move the load toward the desired end point with respect to the axis, and a move-complete circuit for generating a move-complete signal, wherein the improvement comprises: said digital-analog circuitry including a digital null circuit for each axis connected with the countercircuit for the axis and with the move-complete circuit and operable for uniquely sensing error counts registered by the corresponding countercircuit which are within a predetermined null range of count values in the vicinity of 0 including a count value of 0 and including positive and minus count values immediately adjacent to the count value of 0, and responsive to error counts within said predetermined null range to establish a digitally determined null condition, said move-complete circuit being responsive to the existence of a null condition for each axis simultaneously for a predetermined time interval to generate said move-complete signal.
Claim 3
Dependent Claim
182 words
The control system of claim 1 wherein the digital null circuit for each axis generates a predetermined logical signal level when in said digitally determined null condition, said move-complete circuit including a bistable component which is in one stable condition during a positioning operation and which is actuatable to a second stable condition to generate said move-complete signal said move-complete circuit including a logical AND gate having inputs receiving the respective predetermined logical signal levels for the respective axes and for transmitting an output signal so long as said predetermined logical signal levels are both present, a monostable delay circuit connected to the output of the AND gate for beginning a timing cycle in response to said output signals from the AND gate, and means connected to the output of the monostable delay circuit and to the output of the AND gate and to said bistable circuit for shifting the bistable circuit to the second stable condition in response to a delayed output from the monostable delay circuit providing the output signal is still present at the output of said AND gate.
Claim 4
Dependent Claim
345 words
A control system comprising: a source for supplying digitAl command signals representing a movement of a load with respect to X and Y-axes to a desired end point X and Y-axis servo drives coupled to the load and responsive to respective X and Y-axis analog error signals for driving the load as a function of said analog error signals relative to the respective axes, a transducer coupled to each of said servo drives so as to be driven thereby as the load is moved relative to the corresponding axis and for generating motion pulses as a function of the movement of the load relative to the corresponding axis, a countercircuit for each axis connected with said source for registering the digital command signal for the axis and coupled with said transducer for the axis for receiving said motion pulses therefrom and operable to maintain an error count representing the displacement error of the load relative to the desired end point with respect to the axis, digital-analog circuitry for each axis connected with the corresponding countercircuits for providing an analog error signal in accordance with the magnitude of the error count in the corresponding countercircuit and connected with the corresponding servodrive for supplying said analog signal thereto for causing said servodrive to move the load toward the desired end point with respect to the axis, and a move-complete circuit for generating a move-complete signal, said digital-analog circuitry including a digital null circuit for each axis connected with said countercircuit for the axis and directly responsive to a zero count value in digital form in said countercircuit to establish a discrete logical signal level signalling a digitally determined null condition, said move-complete circuit including digital logic circuitry connected to the digital null circuits for the respective axes and responsive to the simultaneous existence of the digitally determined null condition for each axis to begin a timing cycle, said move-complete circuit being responsive to the simultaneous existence of said digitally determined null condition for each axis at the termination of the timing cycle to generate said move-complete signal.
Claim 5
Dependent Claim
345 words
A control system comprising: a source for supplying digitAl command signals representing a movement of a load with respect to X and Y-axes to a desired end point X and Y-axis servo drives coupled to the load and responsive to respective X and Y-axis analog error signals for driving the load as a function of said analog error signals relative to the respective axes, a transducer coupled to each of said servo drives so as to be driven thereby as the load is moved relative to the corresponding axis and for generating motion pulses as a function of the movement of the load relative to the corresponding axis, a countercircuit for each axis connected with said source for registering the digital command signal for the axis and coupled with said transducer for the axis for receiving said motion pulses therefrom and operable to maintain an error count representing the displacement error of the load relative to the desired end point with respect to the axis, digital-analog circuitry for each axis connected with the corresponding countercircuits for providing an analog error signal in accordance with the magnitude of the error count in the corresponding countercircuit and connected with the corresponding servodrive for supplying said analog signal thereto for causing said servodrive to move the load toward the desired end point with respect to the axis, and a move-complete circuit for generating a move-complete signal, said digital-analog circuitry including a digital null circuit for each axis connected with said countercircuit for the axis and directly responsive to a zero count value in digital form in said countercircuit to establish a discrete logical signal level signalling a digitally determined null condition, said move-complete circuit including digital logic circuitry connected to the digital null circuits for the respective axes and responsive to the simultaneous existence of the digitally determined null condition for each axis to begin a timing cycle, said move-complete circuit being responsive to the simultaneous existence of said digitally determined null condition for each axis at the termination of the timing cycle to generate said move-complete signal.
Claim 6
Dependent Claim
104 words
A control system in accordance with claim 3 with said digital null circuit for each axis comprising logical AND circuitry with inputs connected to the respective stages of the countercircuit for responding to the zero count value in digital form in said countercircuit to establish said discrete logical signal level, said move-complete circuit comprising a logical AND circuit having inputs connected to the respective digital null circuits and a timing circuit connected with the output of the logical AND circuit for beginning a timing cycle when both inputs to said logical AND circuit are at said discrete logical signal level signalling said null condition.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |