Patent US6356762B1 successfully refreshed from Google Patents.
US3734574A
Expired / Lapsed
US
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Load sensing control device for a vehicle hydraulic braking system
Assignee: Bendix Corp
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Filing: 1971-03-02
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Granted: 1973-05-22
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Expires: 1991-03-02
Abstract
Abstract A control device is provided for a vehicle hydraulic braking system which includes disc brakes on the front wheels of the vehicle and drum brakes on the rear wheels of the vehicle. The control device is interposed in the brake line between the master cylinder and the front wheel disc brakes and delays fluid communication through the brake line until the fluid pressure in the brake line attains a predetermined level. After the predetermined fluid pressure level is attained, the control device permits fluid communication between the master cylinder and the disc brakes. Means responsive to the load carried by the vehicle are operatively connected with the control device to vary the predetermined fluid pressure level at which fluid communication between the master cylinder and the disc brakes is initiated.
Inventors
- 👤 R Lewis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:35
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/18; B60T8/1837; B60T8/185; B60T8/1806
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
220 words
A control device for use in a vehicle braking system comprising: a housing having an inlet, an outlet, and a bore communicating the inlet with the outlet; valve means within said housing delaying fluid communication between said inlet and outlet until the fluid pressure level at said inlet reaches a predetermined level whereupon said valve means opens to meter fluid communication between the inlet and the outlet to establish a proportionally lower fluid pressure level at said disc brakes than that existing on said drum brakes; and means responsive to the load carried by the vehicle upon which the control device is mounted to change said predetermined pressure level at which the valve means opens and the ratio between the fluid pressure levels at the front and rear brakes as the load carried by the vehicle is increased; said predetermined fluid pressure level at which said valve means opens and the ratio between the front and rear brake fluid pressure levels being decreased as the load carried by the vehicle is increased; and preloaded resilient means yieldably urging said valve means into a position preventing fluid communication between the inlet and outlet; said load responsive means being operatively connected to said resilient means to decrease the preload of said resilient means as the load carried by the vehicle is increased.
Claim 2
Dependent Claim
220 words
A control device for use in a vehicle braking system comprising: a housing having an inlet, an outlet, and a bore communicating the inlet with the outlet; valve means within said housing delaying fluid communication between said inlet and outlet until the fluid pressure level at said inlet reaches a predetermined level whereupon said valve means opens to meter fluid communication between the inlet and the outlet to establish a proportionally lower fluid pressure level at said disc brakes than that existing on said drum brakes; and means responsive to the load carried by the vehicle upon which the control device is mounted to change said predetermined pressure level at which the valve means opens and the ratio between the fluid pressure levels at the front and rear brakes as the load carried by the vehicle is increased; said predetermined fluid pressure level at which said valve means opens and the ratio between the front and rear brake fluid pressure levels being decreased as the load carried by the vehicle is increased; and preloaded resilient means yieldably urging said valve means into a position preventing fluid communication between the inlet and outlet; said load responsive means being operatively connected to said resilient means to decrease the preload of said resilient means as the load carried by the vehicle is increased.
Claim 3
Dependent Claim
69 words
The invention of claim 1: said load responsive means including a plunger slidably mounted in said bore and linkage means operatively connecting the plunger with the vehicle for sensing the load carried by the latter; said resilient means being operatively connected to said plunger and to said valve means, said plunger moving to reduce the preload on said resilient means when the load carried by the vehicle is increased.
Claim 4
Dependent Claim
81 words
The invention of claim 1: said load responsive means including a plunger slidably mounted in said bore and linkage means operatively connecting the plunger with the vehicle; said resilient means being disposed between said plunger and said valve means; said linkage means permitting said plunger to move away from said valve means when the load carried by the vehicle is increased to thereby reduce the preload on said resilient means whereby the force required to open the valve means is reduced.
Claim 5
Dependent Claim
43 words
The invention of claim 3: one end of said plunger extending from said bore for engagement by said linkage means, the other end of said plunger extending into said bore and presenting a surface against which fluid pressure in the bore may act.
Claim 6
Dependent Claim
46 words
The invention of claim 2: each end of said plunger projecting from said housing; said linkage means engaging one end of said plunger; and means operatively connecting the plunger with the valve means; said preloaded resilient mEans being disposed between the plunger and the connecting means.
References Cited (Backward Citations)
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Cited
US3109681A
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US3159433A
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US3414334A
Cited
US3404922A
Cited
US3512845A
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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) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |