US3631944A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plural drive with differential brakes
Assignee: HM Hobson Ltd
•
Filing: 1970-07-16
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Granted: 1972-01-04
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Expires: 1990-07-16
Abstract
Abstract The combination with a hydraulically rotated shaft of a brake comprising unidirectional braking mechanisms which are selectively operable, when applied, one to brake the shaft when it is rotating clockwise and the other to brake the shaft when it is rotating anticlockwise, a piston coupled to the braking mechanisms and subject to the hydraulic pressure which is effective to drive the shaft, the piston maintaining the braking mechanisms in inoperative positions when subject to hydraulic pressure, and a spring biasing the servo piston and operative to apply the braking mechanisms upon removal of the hydraulic pressure.
Inventors
- 👤 Jerzy Leon Courtenay
- 👤 Francis John Neal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:38
CPC Classifications
F; F16; F16D; F16D59/00; F16D59/02; F16D49/00; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19014
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
136 words
The combination, with a pair of hydraulic motors each having an output shaft, of a differential gear coupling said output shafts and a pair of brakes each associated with a respective one of said output shafts, each of said brakes comprising a pair of unidirectional braking mechanisms which are selectively operable, when applied, one to brake the respective output shaft when the output shaft is rotating clockwise and the other to brake said output shaft when said output shaft is rotating anticlockwise, a piston coupled to both braking mechanisms and subject to the hydraulic pressure supplying the hydraulic motor driving said output shaft, said piston maintaining the braking mechanisms in inoperative positions when subject to hydraulic pressure, and a spring biasing the piston and operative to apply the braking mechanisms upon removal of the hydraulic pressure.
Claim 2
Dependent Claim
136 words
The combination, with a pair of hydraulic motors each having an output shaft, of a differential gear coupling said output shafts and a pair of brakes each associated with a respective one of said output shafts, each of said brakes comprising a pair of unidirectional braking mechanisms which are selectively operable, when applied, one to brake the respective output shaft when the output shaft is rotating clockwise and the other to brake said output shaft when said output shaft is rotating anticlockwise, a piston coupled to both braking mechanisms and subject to the hydraulic pressure supplying the hydraulic motor driving said output shaft, said piston maintaining the braking mechanisms in inoperative positions when subject to hydraulic pressure, and a spring biasing the piston and operative to apply the braking mechanisms upon removal of the hydraulic pressure.
Claim 3
Dependent Claim
78 words
A combination as claimed in claim 1, in which each of said brakes includes a fixed cam plate and each braking mechanism of said brake comprises a cage mounted to rotate with respect to the respective output shaft and coupled to the piston, said cage-carrying rollers contacting the output shaft and arranged to become wedged in recesses in the cam plate by rotation of the shaft when the cage is rotated by the piston into a brake-applying position.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-03 | 1975-07-05 | 1976-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-03 | 1979-07-05 | 1980-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-03 | 1983-07-05 | 1984-01-04 | $7700.00 | Window Closed / Lapsed |