Patent US3904250A successfully refreshed from Google Patents.
US3904250A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-skid brake mechanism
Assignee: Aisin Corp
•
Filing: 1973-05-04
•
Granted: 1975-09-09
•
Expires: 1993-05-04
Abstract
Abstract An anti-skid brake mechanism including a master cylinder generating hydraulic pressure, wheel brake cylinders connected to the master cylinder by a hydraulic braking circuit, a skid sensing signal generator, a pump powered hydraulic pressure source, a reservoir hydraulically connected to the pressure source, a cut off valve interposed between the master cylinder and the wheel brake cylinders within the braking circuit for controlling the hydraulic communication therebetween, a hydraulic pressure reducer interposed between the cut off valve and wheel brake cylinders within the braking circuit and including a housing with a piston member slidably fitted therein and cooperatively connected to the cut off valve, an electro-magnetic change over valve selectively communicating the pressure reducer with the pressure source and reservoir in response to a skid sensing signal, and a spring for biasing the piston member against sliding resistance, the spring being interposed between the electro-magnetic valve assembly and hydraulic pressure reducer with the biasing force being at least greater than the sliding force of the piston member.
Inventors
- 👤 Toshihiyuki Kondo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:55
CPC Classifications
B; B60; B60T; B60T17/00; B60T17/18; B60T17/22; B60T13/00; B60T13/10; B60T13/12; B60T13/14; B60T8/00; B60T8/32; B60T8/34; B60T8/36; B60T8/3615; B60T8/3675; B60T8/42; B60T8/4208; B60T8/4225; B60T8/50; B60T8/5018; B60T8/5025; B60T8/5037; B60T8/5043
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
210 words
An anti-skid brake mechanism comprising: a master cylinder generating hydraulic pressure; wheel brake cylinders; a hydraulic braking circuit connecting said master cylinder with said wheel brake cylinders; means for generating a skid sensing signal; a pump powered hydraulic pressure source; a reservior hydraulically connected to said pump powered hydraulic pressure source; a cut-off valve means interposed between said master cylinder and said wheel brake cylinders within said braking circuit for controlling the hydraulic communication therebetween; a hydraulic pressure reducing means interposed between said cutoff valve means and wheel brake cylinders within said braking circuit and including a housing, a piston member slidably fitted within said housing and cooperatively connected to said cut-off valve means; an electro-magnetic change-over valve means selectively communicating said pressure reducing means with said pump powered hydraulic pressure source and said reservoir in response to said skid sensing signal; and means for biasing said piston member of said hydraulic pressure reducing means against the sliding resistance of said piston member, said biasing means being capable of freely assisting the pressure reducing operation of said piston member through its full stroke extent and especially at an approximAtely final stage thereof, where the hydraulic pressure in said wheel brake cylinders has been considerably decreased under a skid braking operation.
Claim 2
Dependent Claim
210 words
An anti-skid brake mechanism comprising: a master cylinder generating hydraulic pressure; wheel brake cylinders; a hydraulic braking circuit connecting said master cylinder with said wheel brake cylinders; means for generating a skid sensing signal; a pump powered hydraulic pressure source; a reservior hydraulically connected to said pump powered hydraulic pressure source; a cut-off valve means interposed between said master cylinder and said wheel brake cylinders within said braking circuit for controlling the hydraulic communication therebetween; a hydraulic pressure reducing means interposed between said cutoff valve means and wheel brake cylinders within said braking circuit and including a housing, a piston member slidably fitted within said housing and cooperatively connected to said cut-off valve means; an electro-magnetic change-over valve means selectively communicating said pressure reducing means with said pump powered hydraulic pressure source and said reservoir in response to said skid sensing signal; and means for biasing said piston member of said hydraulic pressure reducing means against the sliding resistance of said piston member, said biasing means being capable of freely assisting the pressure reducing operation of said piston member through its full stroke extent and especially at an approximAtely final stage thereof, where the hydraulic pressure in said wheel brake cylinders has been considerably decreased under a skid braking operation.
Claim 3
Dependent Claim
31 words
An anti-skid brake mechanism as set forth in claim 1 further comprising switch means for detecting a failure in said hydraulic braking circuit and for providing an indication of said failure.
Claim 4
Dependent Claim
27 words
An anti-skid brake mechanism as set forth in claim 1 wherein said cut-off valve means comprises a ball valve engaged by and controlled by said piston member.
Claim 5
Dependent Claim
63 words
An anti-skid brake mechanism as set forth in claim 1 wherein said electro-magnetic change over valve comprises a pair of alternately functioning passages, one of said passages having an orifice therein and being of a lesser diameter than the other of said passages whereby hydraulic fluid passes through said orifice during a skid condition so as to reduce the speed of said fluid.
Claim 6
Dependent Claim
72 words
An anti-skid brake mechanism as set forth in claim 4 wherein said electro-magnetic change over valve further comprises first and second spool valves each being associated with respective solenoids, said first spool valve being actuable in response to detection of a skid condition to interrupt fluid flow to said cut off valve and direct said fluid flow to said reservoir, said second spool valve controlling fluid flow to said alternately functioning passages.
Claim 7
Dependent Claim
77 words
An anti-skid brake mechanism as set forth in claim 1 wherein said hydraulic pressure reducing means further comprises second and third pistons within said housings, said second piston having a cylinder formed therein for accomodating said third piston so as to form a hydraulic chamber, said second piston being fixed to said housing and said third piston being in direct contact with said first mentioned piston so as to control the movement of said first mentioned piston.
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) | 1978-09-08 | 1979-03-10 | 1979-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-08 | 1983-03-10 | 1983-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-08 | 1987-03-10 | 1987-09-09 | $7700.00 | Window Closed / Lapsed |