US4250438A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digitally controlled acceleration and deceleration system
Assignee: Oki Electric Industry Co Ltd
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Filing: 1978-03-07
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Granted: 1981-02-10
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Expires: 1998-03-07
Abstract
Abstract A digitally controlled acceleration and deceleration system in which the goal velocity applied to the object in the acceleration mode and the deceleration mode changes linearly, instead of the flat goal velocity, thus, the acceleration and/or deceleration applied to the object to be controlled in the feedback loop becomes flat, and the acceleration time and/or deceleration time is reduced. The outputs of the variable frequency pulse generator and the fixed frequency pulse generator are combined together to provide said goal velocity, and the number of the sum of two pulse generators is utilized as a command position for the movement of the object.
Inventors
- 👤 Fumio Onoda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 03:10
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/416
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
333 words
A digitally controlled acceleration and deceleration system comprising a motor for moving a table, a motor drive for driving said motor, a first detector means for detecting the present position of said table, a second detector means for detecting the velocity of said table, circuit means for providing a product of said detected velocity and a predetermined constant τ, position register means for receiving an input command pulse from a command position apparatus and accumulating the same to provide the goal position for said table, first comparator means for providing a difference between the output of said position register means and said first detector means, and a second comparator for providing a difference between the output of said first comparator means and the output of said circuit means, characterized in that said command position apparatus comprises; (a) variable pulse generator means for providing a pulse train whose frequency during an acceleration mode increases from zero to a predetermined frequency F at a constant rate F/a; during a constant speed mode said frequency F is maintained; in a deceleration mode said frequency decreases from F to zero at a constant rate F/b; and in an acceleration mode said frequency increases at a constant rate F/a until the beginning of the deceleration mode, and in the deceleration mode said frequency decreases to zero at a constant rate F/b, (b) first fixed pulse generator means for providing a pulse train at a frequency τ·F/a in the acceleration mode, (c) second fixed pulse generator means for providing a pulse train at a frequency τ·F/b in the deceleration mode, (d) means for providing a moving direction to the pulse train of said variable pulse generator means, (e) means for providing a moving direction to the pulse train of said first fixed generator means, (f) means for providing a moving direction to the pulse train of said second fixed pulse generator means, and (g) means for combining said pulse trains for providing input command pulses to said position register.
Claim 2
Dependent Claim
333 words
A digitally controlled acceleration and deceleration system comprising a motor for moving a table, a motor drive for driving said motor, a first detector means for detecting the present position of said table, a second detector means for detecting the velocity of said table, circuit means for providing a product of said detected velocity and a predetermined constant τ, position register means for receiving an input command pulse from a command position apparatus and accumulating the same to provide the goal position for said table, first comparator means for providing a difference between the output of said position register means and said first detector means, and a second comparator for providing a difference between the output of said first comparator means and the output of said circuit means, characterized in that said command position apparatus comprises; (a) variable pulse generator means for providing a pulse train whose frequency during an acceleration mode increases from zero to a predetermined frequency F at a constant rate F/a; during a constant speed mode said frequency F is maintained; in a deceleration mode said frequency decreases from F to zero at a constant rate F/b; and in an acceleration mode said frequency increases at a constant rate F/a until the beginning of the deceleration mode, and in the deceleration mode said frequency decreases to zero at a constant rate F/b, (b) first fixed pulse generator means for providing a pulse train at a frequency τ·F/a in the acceleration mode, (c) second fixed pulse generator means for providing a pulse train at a frequency τ·F/b in the deceleration mode, (d) means for providing a moving direction to the pulse train of said variable pulse generator means, (e) means for providing a moving direction to the pulse train of said first fixed generator means, (f) means for providing a moving direction to the pulse train of said second fixed pulse generator means, and (g) means for combining said pulse trains for providing input command pulses to said position register.
Claim 3
Dependent Claim
306 words
A digitally controlled acceleration and deceleration system according to claim 1, wherein said command position apparatus further comprises: (a) circuit means for calculating aF/2, L-aF/2-bF/2, and bF/2 for the acceleration moving length, the constant speed moving length and the deceleration moving length, respectively, when the command moving length L satisfied L>aF/2+bF/2, and calculating (a/(a+b))L,O, and (b/a+b))L for the acceleration moving length, the constant speed moving length and the deceleration moving length, respectively, when the command moving length L satisfies L≦aF/2+bF/2, (b) circuit means for storing the acceleration moving length and providing the content of the same to a subtracting counter means at the beginning of the acceleration, (c) circuit means for storing the constant speed moving length and providing the content of the same to said subtracting counter means at the beginning of the constant speed mode, (d) circuit means for storing the deceleration moving length and providing the content of the same to said subtracting counter means at the beginning of the deceleration, (e) subtracting counter means for subtracting the pulse train of said variable pulse generator means from an input numerical value, (f) circuit means for providing a zero detecting signal when the content of said subtracting counter means is zero, (g) control circuit means for changing said operational mode, upon receipt of said zero detecting signal, from the acceleration mode to the constant speed mode, from the constant speed mode to the deceleration mode, or from the deceleration mode to stop, (h) up/down counter means for incrementing the content of the same by the pulse train of the first fixed pulse generator means and decrementing the content of the same by the pulse train of the second fixed pulse generator means, and (i) circuit means for stopping said second fixed pulse generator means when the content of said up/down counter means is zero.
References Cited (Backward Citations)
US3241015A
Cited
US3952238A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-10 | 1984-08-11 | 1985-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-10 | 1988-08-11 | 1989-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-10 | 1992-08-11 | 1993-02-10 | $7700.00 | Window Closed / Lapsed |