Patent US3922858A successfully refreshed from Google Patents.
US3922858A
Expired / Lapsed
US
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Tandem master cylinders for hydraulic braking systems
Assignee: Girling Ltd
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Filing: 1974-02-12
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Granted: 1975-12-02
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Expires: 1994-02-12
Abstract
Abstract In a tandem master cylinder for hydraulic braking systems a pedal-operated main piston is coupled to a secondary piston by a split collet embracing heads on aligned axial stems on the pistons, said heads being axially movable in a gap in the collet of which the axial length determines the maximum separation of the pistons.
Inventors
- 👤 Francis Antony Dawson Sadler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:38
CPC Classifications
B; B60; B60T; B60T11/00; B60T11/10; B60T11/16; B60T11/20
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
99 words
A tandem master cylinder for hydraulic braking systems for vehicles in which a pedal-operated main piston working in a part of the cylinder bore is coupled to a secondary piston working in another part of the bore by means limiting relative axial movement between the pistons in both directions and the pistons are urged apart by a spring, wherein the main and secondary pistons are interconnected by a split collet embracing heads on aligned axial stems on the pistons, said collet including axially spaced abutment means engageable by said heads; and serving to limit axial separation of the pistons.
Claim 2
Dependent Claim
99 words
A tandem master cylinder for hydraulic braking systems for vehicles in which a pedal-operated main piston working in a part of the cylinder bore is coupled to a secondary piston working in another part of the bore by means limiting relative axial movement between the pistons in both directions and the pistons are urged apart by a spring, wherein the main and secondary pistons are interconnected by a split collet embracing heads on aligned axial stems on the pistons, said collet including axially spaced abutment means engageable by said heads; and serving to limit axial separation of the pistons.
Claim 3
Dependent Claim
37 words
A tandem master cylinder as in claim 1 wherein said collet comprises co-operating semi-cylindrical parts having a central gap in which said heads are axially movable and at the ends of which are located said abutment means.
Claim 4
Dependent Claim
60 words
A tandem master cylinder as in claim 1 wherein one of said heads is formed on an axial extension of the rear end of the secondary piston and the other head is formed on an axial stem secured into the main piston within a counterbore in the forward end of said piston which receives the rear end of said collet.
References Cited (Backward Citations)
US3488959A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-01 | 1979-06-02 | 1979-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-01 | 1983-06-02 | 1983-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-01 | 1987-06-02 | 1987-12-02 | $7700.00 | Window Closed / Lapsed |