Patent US3638528A successfully refreshed from Google Patents.
US3638528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic boost device with auxiliary fluid supply
Assignee: Bendix Corp
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Filing: 1970-06-17
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Granted: 1972-02-01
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Expires: 1990-06-17
Abstract
Abstract A hydraulic brake booster is disclosed which provides a power assist to the vehicle operator during a brake application. Pressurized hydraulic fluid is supplied to the booster from the vehicle''s power steering pump. A charging valve carried in the booster housing permits flow of fluid into an accumulator when the fluid pressure level at the booster inlet exceeds the fluid pressure level in the accumulator. When flow of fluid to the inlet is terminated the charging valve is opened during a brake application to permit flow of fluid from the accumulator to the booster thereby allowing normal operation of the booster for a limited number of brake applications.
Inventors
- 👤 Richard L Lewis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:47
CPC Classifications
B; B60; B60T; B60T13/00; B60T13/10; B60T13/12; B60T13/14; B60T13/148; B60T13/16; B60T13/161; B60T13/162
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
209 words
In a vehicle hydraulic system: a hydraulic boost device including a housing having an inlet, an outlet, a first bore communicating the inlet with the outlet, and a chamber in fluid communication with the inlet; piston means shiftable in said chamber; a pressure source in fluid communication with said inlet; first valve means shiftable in said housing from a first position in which substantially all of the fluid flowing into the inlet is directed to the outlet toward a second position, said first valve means communicating successively higher fluid pressure levels into said chamber as the first valve means is shifted toward said second position; operator-actuated means for actuating said first valve member; means for storing fluid under pressure in fluid communication with said housing; and second valve means for controlling fluid communication between the storage means and the chamber and shiftable from a first position in which flow of fluid from the storage means to the bore is prevented to a second position permitting fluid communication between the storage means and the bore; said first valve means including means to shift said second valve means to its second position upon movement of the first valve means to its second position when fluid flow to said inlet is reduced.
Claim 2
Dependent Claim
209 words
In a vehicle hydraulic system: a hydraulic boost device including a housing having an inlet, an outlet, a first bore communicating the inlet with the outlet, and a chamber in fluid communication with the inlet; piston means shiftable in said chamber; a pressure source in fluid communication with said inlet; first valve means shiftable in said housing from a first position in which substantially all of the fluid flowing into the inlet is directed to the outlet toward a second position, said first valve means communicating successively higher fluid pressure levels into said chamber as the first valve means is shifted toward said second position; operator-actuated means for actuating said first valve member; means for storing fluid under pressure in fluid communication with said housing; and second valve means for controlling fluid communication between the storage means and the chamber and shiftable from a first position in which flow of fluid from the storage means to the bore is prevented to a second position permitting fluid communication between the storage means and the bore; said first valve means including means to shift said second valve means to its second position upon movement of the first valve means to its second position when fluid flow to said inlet is reduced.
Claim 3
Dependent Claim
52 words
The invention of claim 1: said means to shift said second valve means including a camming surface on said first valve means; and a plunger operably connected to said first and second valve means, said plunger being shifted by said camming surface to shift said second valve means to its second position.
Claim 4
Dependent Claim
59 words
The invention of claim 2: said first valve means being shiftable within a first bore communicating the inlet with the outlet; a member projecting into said bore slidably engaging said first valve means; said member shifting said second valve means from its first position to its second position upon movement of the first valve means to its second position.
Claim 5
Dependent Claim
82 words
The invention of claim 2: said first valve means being shiftable in a first bore within the housing communicating the inlet and outlet; said housing defining a second bore therewithin in fluid communication with said first bore and with said fluid storage means; said second valve means being housed in said second bore; and means operatively engaging said first valve means for shifting said second valve means to its second position when said first valve means is moved to its first position.
Claim 6
Dependent Claim
159 words
The invention of claim 2: said first valve means being shiftable in a first bore communicating the inlet with the outlet; said housing defining a second bore therewithin in fluid communication with said first bore to communicate the inlet and with said fluid storage means; said second valve means including a valve seat mounted in said second bore and a valve member yieldably urged into engagement with said valve seat to prevent flow of fluid between the storage means and the first bore, but moving from said seat to permit flow of fluid from the first bore to the storage means when the fluid pressure level at the inlet exceeds the fluid pressure level in the storage means; and means operatively connecting said first valve means and said valve member for forcing the latter off said seat when the first valve means is shifted past its second position to permit flow of fluid from the accumulator to the bore.
Claim 7
Dependent Claim
50 words
The invention of claim 5: said valve seat being annular to define a passage extending therethrough, said valve member being yieldably urged into a position closing said passage; said connecting means being a plunger movable within said housing upon said movement of the first valve means to its second position.
Claim 8
Dependent Claim
77 words
The invention of claim 6: saId first valve means having a substantially constant diameter section and a tapered section presenting a camming surface extending from said constant diameter section; said plunger slidably engaging said constant diameter section as said first valve means is shifted from said first position, said camming surfaces moving said plunger within said second bore to lift the valve member off the seat when said second valve means is shifted to its second position.
Claim 9
Dependent Claim
46 words
The invention of claim 6: said plunger being slidable in said second bore and having a projecting portion extending through the passage defined by the valve seat for engagement with the valve member when the plunger is moved to lift the member off of the seat.
Claim 10
Dependent Claim
28 words
The invention of claim 8: said plunger having channel means extending therethrough to permit flow of fluid through the plunger between the second valve means and said bore.
Claim 11
Dependent Claim
21 words
The invention of claim 5; and resilient means in said second bore yieldably urging said valve member against said valve seat.
Claim 12
Dependent Claim
33 words
The invention of claim 2; and a plunger movable in said housing for shifting said second valve means to its second position upon movement of the first valve means past its second position.
Claim 13
Dependent Claim
79 words
The invention of claim 11: said first valve means having a substantially constant diameter section and a tapered section presenting a camming surface extending from said constant diameter section; said plunger slidably engaging said constant diameter section when said first valve means is shifted from said first position, said camming surface moving said plunger within said second bore to shift said second valve means to its second position when said second valve means is shifted to its second position.
Claim 14
Dependent Claim
28 words
The invention of claim 11: said plunger having channel means extending therethrough to permit flow of fluid through the plunger between the second valve means and said chamber.
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) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |