US3731176A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Deceleration and stop-lock motor control apparatus
Assignee: International Business Machines Corp
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Filing: 1972-04-21
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Granted: 1973-05-01
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Expires: 1992-04-21
Abstract
Abstract A motor, moving at a known speed, is stopped in a controlled manner by a speed control servomechanism which compares the actual speed-versus-distance deceleration profile to an optimum or desired speed-versus-distance deceleration profile, and variably controls the reverse energization, or plugging, of the motor in a manner devised to achieve the desired profile. When the speed servo has reduced motor speed to a low level, and preferably zero, a stop-lock control servomechanism is enabled to position and maintain the motor at a preselected stop-lock position. The stop-lock servo implements a motor-control algorithm which, for a given position error, provides a higher magnitude motor energization when the motor is moving away from the stop-lock position than when the motor is moving back toward the stop-lock position. This control algorithm provides increased servo gain when the motor is moving away from the stop-lock position.
Inventors
- 👤 J Mitchell
- 👤 S Roberts
- 👤 Pelt R Van
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:04
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/21; G05B19/23; G05B19/231; G05B19/232; G11; G11B; G11B15/00; G11B15/18; G11B15/46; G11B15/48; G05B2219/00; G05B2219/30; G05B2219/41; G05B2219/41021; G05B2219/41244; G05B2219/43; G05B2219/43006; G05B2219/43179; G05B2219/43194
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
159 words
Stop control apparatus for bringing a motor to a zero speed condition and for maintaining the motor stop-locked at a given position, comprising: transducing means controlled by said motor and providing motor speed, motor distance, and motor direction information; speed-control means controlled by said transducing means and operable upon the occurrence of a stop command to control motor energization in a manner devised to achieve subsequent zero motor speed; stop-lock control means controlled by said transducing means and operable subsequent to operation of said speed control means to stop-lock said motor at a given position; and means responsive to a stop-lock position error and to the direction of motor movement relative to said given position to energize said motor in a manner to return said motor to said given position, said last-named means being constructed and arranged to implement a control algorithm providing increased gain and increased motor energization when the motor is moving away from said given position.
Claim 2
Dependent Claim
159 words
Stop control apparatus for bringing a motor to a zero speed condition and for maintaining the motor stop-locked at a given position, comprising: transducing means controlled by said motor and providing motor speed, motor distance, and motor direction information; speed-control means controlled by said transducing means and operable upon the occurrence of a stop command to control motor energization in a manner devised to achieve subsequent zero motor speed; stop-lock control means controlled by said transducing means and operable subsequent to operation of said speed control means to stop-lock said motor at a given position; and means responsive to a stop-lock position error and to the direction of motor movement relative to said given position to energize said motor in a manner to return said motor to said given position, said last-named means being constructed and arranged to implement a control algorithm providing increased gain and increased motor energization when the motor is moving away from said given position.
Claim 3
Dependent Claim
36 words
Stop control apparatus as defined in claim 1 wherein said last-named means is additionally constructed and arranged to implement a control algorithm providing decreased dead band when the motor is moving away from said given position.
Claim 4
Dependent Claim
70 words
Stop control apparatus as defined in claim 1 wherein said speed control means includes means operable to compaRe the actual speed versus distance profile of motor deceleration to an optimum speed versus distance profile and to originate a speed-error signal as a result of said comparison, and including a lag-type filter connected to receive said speed-error signal as an input, said filter providing a filtered output to control motor energization.
Claim 5
Dependent Claim
62 words
Stop control apparatus as defined in claim 1 wherein said stop-lock control means includes means operable to compare the actual motor position to said given position and to originate a position-error signal as a result of said comparison, and including a lead-type filter connected to receive said position-error signal as an input, said filter providing a filtered output to control motor energization.
Claim 6
Dependent Claim
97 words
Stop control apparatus as defined in claim 1 including first and second filter means, power amplifier means connected to said motor and operable to energize said motor in both the speed and stop-lock modes of operation of said stop control apparatus, and means operable to connect said first filter in a circuit with said power amplifier means when the stop control means is operating in the speed mode, and to connect said second filter in circuit with said power amplifier means when the stop control apparatus makes a transition from the speed mode to the stop-lock mode.
Claim 7
Dependent Claim
95 words
Stop control apparatus as defined in claim 1 wherein said transducing means includes a digital encoder and sampled-data means controlled thereby to periodically provide updated speed, distance, and direction information, said speed control means being responsive to said transducing means as the speed of said motor decreases to a speed slightly greater than zero speed, whereupon control of said motor by said speed control means is interrupted; and delay means operable to delay operation of said stop-lock control means, such that said stop-lock control means is rendered operable when said motor speed is approximately zero.
Claim 8
Dependent Claim
35 words
Stop control apparatus as defined in claim 6 wherein said speed control means is operable to reverse energize said motor, and wherein said motor is de-energized during the timing period of said time delay means.
Claim 9
Dependent Claim
108 words
Stop control apparatus as defined in claim 7 wherein said digital encoder provides an output pulse for each unit of movement of said motor and wherein speed information is generated by digital means in the form of a number whose magnitude represents the time interval between adjacent output pulses of said encoder, wherein said distance information is generated by digital means in the form of a number whose magnitude represents the sum of the output pulses received from said encoder; and wherein the digital means providing said distance information is operable to interrupt operation of said speed control means at a predetermined distance relative to said given position.
Claim 10
Dependent Claim
107 words
Stop control apparatus as defined in claim 8 wherein said speed control means is operable to periodically compare the speed information number to a number representing a desired motor speed at a given distance position and to generate a speed-error number as a result of said comparison, wherein a predetermined distance information number is effective to interrupt operation of said speed control means; and wherein said stop-lock control means is operable after the timing period of said time delay means to compare the distance information number to a number representing said given position and to generate a stop-lock position error number as a result of said comparison.
Claim 11
Dependent Claim
140 words
Stop control apparatus as defined in claim 9 including a digital-to-analog converter connected to receive said speed error number when said speed control means is operable, connected to receive a speed error number equal to a command for motor deenergization during the timing period of said time delay means, and connected to receive said position error number after the timing period of said time delay means; including power amplifier means having an output connected to control energizaTion of said motor and having an input connected to receive the output of said digital-to-analog converter; and means controlled by the direction information provided by said transducing means and connected to control the transfer of said position-error number to said digital-to-analog converter in a manner to effectively increase the magnitude of said number when the motor is moving away from said given point.
Claim 12
Dependent Claim
67 words
Stop control apparatus as defined in claim 10 including first and second filter means selectively adapted to be connected intermediate said digital-to-analog converter and the input of said power amplifier means, and means operable to select said first filter when the stop control apparatus is operating in the speed mode, and to select said second filter when the stop control apparatus is operating in the stop-lock mode.
Claim 13
Dependent Claim
25 words
Stop control apparatus as defined in claim 11 wherein said first filter is a lag-type filter and wherein said second filter is a lead-type filter.
Claim 14
Dependent Claim
48 words
Stop control apparatus as defined in claim 12 including feedback means connected to said motor and providing a negative feedback signal to the input of said power amplifier means in accordance with the magnitude of the energization of said motor by the output of said power amplifier means.
Claim 15
Dependent Claim
122 words
Stop-lock control means for maintaining a motor at a stop-lock position, comprising: transducing means controlled by said motor and providing motor distance and motor direction information output signals; means responsive to the distance output signal of said transducing means and operable to compare said signal to a signal representing the stop-lock position to thereby generate a position-error signal; and motor control means responsive to said position-error signal and to the direction output signal of said transducing means to energize said motor in a manner to return said motor to said stop-lock position, said motor control means being constructed and arranged to implement a motor-control algorithm providing increased gain and increased motor energization when the motor is moving away from said stop-lock position.
Claim 16
Dependent Claim
122 words
Stop-lock control means for maintaining a motor at a stop-lock position, comprising: transducing means controlled by said motor and providing motor distance and motor direction information output signals; means responsive to the distance output signal of said transducing means and operable to compare said signal to a signal representing the stop-lock position to thereby generate a position-error signal; and motor control means responsive to said position-error signal and to the direction output signal of said transducing means to energize said motor in a manner to return said motor to said stop-lock position, said motor control means being constructed and arranged to implement a motor-control algorithm providing increased gain and increased motor energization when the motor is moving away from said stop-lock position.
Claim 17
Dependent Claim
36 words
Stop-lock control means as defined in claim 14 wherein said motor-control means is additionally constructed and arranged to implement a motor-control algorithm providing decreased dead band when the motor is moving away from said stop-lock position.
Claim 18
Dependent Claim
97 words
Stop-lock control means as defined in claim 14 wherein said transducing means includes a digital encoder providing an output pulse for each increment of movement of said motor, wherein said distance output signal is a number whose magnitude is an algebraic summation of the units of motor movement away from and back toward said stop-lock position; and wherein said motor control means includes means to compare said number to a number representing the stop-lock position to thereby originate a position-error number whose magnitude is a measure of the position of said motor relative to said stop-lock position.
Claim 19
Dependent Claim
80 words
Stop-lock control means as defined in claim 16 wherein said motor control means includes power amplifier means having an input and having an output connected to energize said motor, a digital-to-analog converter connected to receive said position-error number and providing an analog output to the input of said power amplifier means, and means responsive to said direction output signal and connected to effectively increase the magnitude of said position-error number when said motor is moving away from said stop-lock position.
Claim 20
Dependent Claim
49 words
Stop-lock control means as defined in claim 17 wherein said motor control means includes a signal modifying network connected to receive the output of said digital-to-analog converter and to provide an analog output to the input of said power amplifier means, said analog output having a rate-of-motor movement component.
Claim 21
Dependent Claim
17 words
Stop-lock control means as defined in claim 18 wherein said signal modifying network is a lead-type filter.
Claim 22
Dependent Claim
38 words
Stop-lock control means aS defined in claim 19 including feedback means connected to said motor and providing a negative feedback to the input of said power amplifier means in accordance with the magnitude of energization of said motor.
References Cited (Backward Citations)
US3571685A
Cited
US3644720A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-30 | 1976-10-30 | 1977-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-30 | 1980-10-30 | 1981-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-30 | 1984-10-30 | 1985-05-01 | $7700.00 | Window Closed / Lapsed |