Patent US3754841A successfully refreshed from Google Patents.
US3754841A
Expired / Lapsed
US
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Vacuum intensified brake booster system
Assignee: Bendix Corp
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Filing: 1971-05-14
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Granted: 1973-08-28
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Expires: 1991-05-14
Abstract
Abstract An apparatus for sensing the available vacuum in a power braking system having the ability to generate an additional source of vacuum which can be combined with the vacuum in the system to maintain the vacuum in the system within a predetermined range.
Inventors
- 👤 F Grabb
- 👤 M Beck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:23
CPC Classifications
F; F04; F04B; F04B45/00; F04B45/04; B; B60; B60T; B60T17/00; B60T17/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
223 words
A vacuum intensifier for use in a power braking system comprising: a housing having a reference chamber, a control chamber and a power chamber; first means located in said reference chamber for developing a reference pressure below the pressure source of a first fluid under pressure; second means located in said control chamber being connected to said first means and an operational conduit in communication with a first source of partial vacuum for distinguishing a pressure differential between said reference pressure and the partial vacuum available in said operational conduit; and valve means located in said power chamber responsive to said second means for controlling a variable area inlet in communication with a second source of fluid under pressure, said controlled variable area inlet permitting said second source of fluid to flow through a restricted section in said power chamber in response to the available partial vacuum in the operational conduit, said restricted section causing the pressure of the second source of fluid flowing therethrough to be lowered below the fluid pressure of said second source of fluid while at said variable area inlet, said restriction having an orifice connected to said operational conduit, said lowered fluid pressuRe of said second fluid combining with said source of partial vacuum to maintain the partial vacuum level in the operational conduit within a predetermined range.
Claim 2
Dependent Claim
223 words
A vacuum intensifier for use in a power braking system comprising: a housing having a reference chamber, a control chamber and a power chamber; first means located in said reference chamber for developing a reference pressure below the pressure source of a first fluid under pressure; second means located in said control chamber being connected to said first means and an operational conduit in communication with a first source of partial vacuum for distinguishing a pressure differential between said reference pressure and the partial vacuum available in said operational conduit; and valve means located in said power chamber responsive to said second means for controlling a variable area inlet in communication with a second source of fluid under pressure, said controlled variable area inlet permitting said second source of fluid to flow through a restricted section in said power chamber in response to the available partial vacuum in the operational conduit, said restricted section causing the pressure of the second source of fluid flowing therethrough to be lowered below the fluid pressure of said second source of fluid while at said variable area inlet, said restriction having an orifice connected to said operational conduit, said lowered fluid pressuRe of said second fluid combining with said source of partial vacuum to maintain the partial vacuum level in the operational conduit within a predetermined range.
Claim 3
Dependent Claim
114 words
The vacuum intensifier as recited in claim 1 wherein said second means includes: wall means for dividing said control chamber into a front chamber and a rear chamber, said front chamber being connected to receive said reference pressure established by said first means, said rear chamber being connected to receive partial vacuum in said operational conduit, said wall means responding to a pressure differential between said front and rear chamber to transmit an operational signal to said valve means; and resilient means connected to said wall means and the housing of said control chamber for providing a predetermined load which the wall means must overcome before transmitting said operational signal to said valve means.
Claim 4
Dependent Claim
114 words
The vacuum intensifier as recited in claim 2 wherein said first means includes: a fixed area inlet communicating with a constant volume chamber in said housing of said reference chamber, said fixed area inlet being connected to said first source of fluid under pressure; and nozzle means attached to an outlet communicating with said constant volume chamber and in communication with said first source of partial vacuum, said nozzle means having an orifice connected to said front chamber of said second means for communicating a pressure signal resulting from the flow of the first source of fluid past said orifice in response to the intensity of the available partial vacuum of said first source.
Claim 5
Dependent Claim
148 words
The vacuum intensifier as recited in claim 3 wherein said nozzle means includes: a converging interior section adjacent the outlet of said constant volume chamber; a throat section adjacent said converging section having an interior surface parallel to the axis of flow of the fluid, said orifice connected to said second means being located in said throat section; and a diverging section connected by a conduit to said first source of partial vacuum, said converging section permitting the fluid flow of said first fluid to achieve a maximum velocity through said throat section in a direct relationship to the discharge flow of said first fluid from the diverging section caused by said first source of partial vacuum, said maximum velocity of fluid through said throat lowering the static pressure of the first fluid below the static pressure of the fluid at the outlet of the constant volume chamber.
Claim 6
Dependent Claim
57 words
The vacuum intensifier as recited in claim 4 wherein said valve means include: a plunger means slidable in a bore of said housing, said plunger means being connected to said wall means, said plunger means moving in response to said wall means to control the flow of the second source of fluid through said variable area inlet.
Claim 7
Dependent Claim
135 words
The vacuum intensifier as recited in claim 5, wherein said power chamber further includes: a dampening chamber connected to said variable area inlet with an outlet whose inner surface converges into said restricted section; said dampening chamber stabilizing the flow of the second source of fluid by providing a large area for storing a large quantity of the second fluid under a constant pressure below the pressure of the second fluid before entering said variable area inlet; and diffuser means having one end connected to said restricted section and the other end connected to said first source of partial vacuum, said diffuser having an interior surface sloping toward the other end whose opening approaches said outlet from the dampening chamber for reducing pressure losses between the variable area inlet and said source of partial vacuum.
Claim 8
Dependent Claim
23 words
The vacuum intensifier as recited in claim 6, wherein said first and second sources of fluid under pressure is equal to atmospheric pressure.
Claim 9
Dependent Claim
38 words
The vacuum intensifier as recited in claim 7 wherein said valve means further includes: push rod means connected to said wall means and saiD plunger means for directly transmitting movement from said wall means to said plunger means.
Claim 10
Dependent Claim
85 words
The vacuum intensifier as recited in claim 8 wherein said plunger means further includes: a piston member with first and second cylindrical portions of equal diameter separated by a stem of a smaller diameter whose length is equal to the diameter of the variable area inlet, said first and second cylindrical portions being equally acted on by air under atmospheric pressure communicated to said bore to reduce the possibility of an outside pressure differential affecting the position of the wall means in said control chamber.
Claim 11
Dependent Claim
58 words
The vacuum intensifier as recited in claim 9 further including: filter means located adjacent said fixed inlet through which said first source of fluid flows and adjacent said variable area inlet through which said second source of fluid flows for preventing contaminants from entering and disrupting the fluid flow in the constant volume chamber and the dampening chamber.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |