Patent US3733529A successfully refreshed from Google Patents.
US3733529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plural motor tape drive speed control
Assignee: Ross Controls Corp
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Filing: 1972-05-22
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Granted: 1973-05-15
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Expires: 1992-05-22
Abstract
Abstract Controls for winding a strip such as magnetic recording tape at a constant linear speed on to a take-up reel from a supply reel. The controls are responsive to the instantaneous angular speeds of both reels, maintaining at a substantially constant value the ratio of the product of the squares of the speeds to the sum of the squares, by varying the speed of the take-up reel while sufficiently restraining the supply reel to maintain tension on the strip.
Inventors
- 👤 E Ross
- 👤 G Baule
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:20
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/18; G11B15/43
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
119 words
Means to wind a strip at a constant linear speed on to a take-up reel from a supply reel, said means having, in combination, a variable speed drive motor having a rotor with means for rotating the take-up reel, energizing means for the drive motor responsive to a variable applied input signal to vary the speed of the drive motor in a direction to wind the strip on to the take-up reel, means restraining the supply reel to maintain tension on the strip, and means responsive to the angular speeds of both reels to vary the input signal to maintain substantially constant the ratio of the product of the squares of said speeds to the sum of said squares.
Claim 2
Dependent Claim
119 words
Means to wind a strip at a constant linear speed on to a take-up reel from a supply reel, said means having, in combination, a variable speed drive motor having a rotor with means for rotating the take-up reel, energizing means for the drive motor responsive to a variable applied input signal to vary the speed of the drive motor in a direction to wind the strip on to the take-up reel, means restraining the supply reel to maintain tension on the strip, and means responsive to the angular speeds of both reels to vary the input signal to maintain substantially constant the ratio of the product of the squares of said speeds to the sum of said squares.
Claim 3
Dependent Claim
32 words
The combination according to claim 1, in which the means restraining the supply reel comprise a drag motor energized in a direction tending to wind the strip on to the supply reel.
Claim 4
Dependent Claim
14 words
The combination according to claim 2, including means to energize the drag motor variably.
Claim 5
Dependent Claim
41 words
The combination according to claim 3, in which the drive and drag motors are each adapted to develop increasing torque with increasing applied current, the current applied to the drag motor decreasing as the current applied to the drive motor increases.
Claim 6
Dependent Claim
53 words
The combination according to claim 1, in which the last-recited means include a tachometer for each of said reels, a function generator having an input connected with at least one of said tachometers, and a comparison circuit having an input connection with the function generator and an output connection with the drive motor.
Claim 7
Dependent Claim
18 words
The combination according to claim 5, in which the means restraining the supply reel comprise a drag motor.
Claim 8
Dependent Claim
29 words
The combination according to claim 6, in which the drive and drag motors each develop a counter E.M.F. varying with angular velocity and the tachometers comprise circuits responsive thereto.
Claim 9
Dependent Claim
16 words
The combination according to claim 5, in which both tachometers are connected with the function generator.
Claim 10
Dependent Claim
22 words
The combination according to claim 8, in which the comparison circuit compares the output of the function generator with a constant signal.
Claim 11
Dependent Claim
39 words
The combination according to claim 8, in which the function generator is responsive to the difference between the tachometer outputs and the comparison circuit compares the output of the function generator with the output of the drive motor tachometer.
Claim 12
Dependent Claim
43 words
The combination according to claim 5, in which the function generator has an input connected with one of said tachometers and the comparison circuit has one input connected with the function generator and a second input connected with the other of said tachometers.
Claim 13
Dependent Claim
40 words
The combination according to claim 9, in which the function generator generates a function approximately proportional to the ratio between the product of tHe angular velocities of the reels and the square root of the sum of the squares thereof.
Claim 14
Dependent Claim
28 words
The combination according to claim 11, in which the function generator generates a function of the output of one tachometer and of the linear velocity of the strip.
References Cited (Backward Citations)
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US3156397A
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US3218529A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-14 | 1976-11-13 | 1977-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-14 | 1980-11-13 | 1981-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-14 | 1984-11-13 | 1985-05-15 | $7700.00 | Window Closed / Lapsed |