Patent EP0016906A1 successfully refreshed from Google Patents.
US3901562A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brake pipe reduction indicating apparatus
Assignee: Wabco Ltd
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Filing: 1974-03-15
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Granted: 1975-08-26
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Expires: 1994-03-15
Abstract
Abstract Brake pipe reduction indicating apparatus for railway braking equipment in which a differential pressure gauge is employed for comparing brake pipe pressure with the level of equalizing reservoir pressure prevailing at the onset of brake pipe pressure reduction initiated by the engineer''s brake valve, thereby providing the engineer with a positive visual indication of the actual brake pipe reduction taking place. The invention eliminates the necessity of the engineer to rely solely on his judgement in effecting an equalizing reservoir pressure reduction sufficient for compensating for a brake pipe pressure gradient without the benefit of an indicator which, at least, indicates the upper pressure limit of the gradient, that is, the specific pressure to which the equalizing reservoir pressure must be reduced to initiate brake pipe reduction.
Inventors
- 👤 Peter H Powell
- 👤 Archibald J Harvey Peterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:09
CPC Classifications
B; B60; B60T; B60T15/00; B60T15/02; B60T15/36; B60T15/48; B60T17/00; B60T17/18; B60T17/22; B60T17/228
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
211 words
Brake pipe reduction indicating apparatus for use with automatic railway vehicle brake equipment and comprising: a. first means normally charged to a predetermined fluid pressure and operative responsively to a reduction of such fluid pressure therein for causing a brake application on the vehicle commensurate with the degree of reduction; b. second means normally charged with fluid pressure at a degree corresponding to said predetermined fluid pressure; c. operator''s means selectively operable to a plurality of positions for initiating a reduction of fluid pressure in said second means to a selected reduced degree according to the position to which said operator''s means is operated, d. said operator''s means including relay valve means operable responsively to reduction of fluid pressure in said second means to a degree corresponding to the degree of fluid pressure prevailing in said first means at the time said reduction is initiated, for effecting reduction of pressure in said first means to said selected reduced degree; and wherein the improvement comprises: e. indicating means cooperatively responsive to reduction of fluid pressure in said first and second means for indicating the pressure differential between the initial pressure prevailing in said first means at the onset of said reduction and the final pressure prevailing therein at termination of such reduction.
Claim 2
Dependent Claim
211 words
Brake pipe reduction indicating apparatus for use with automatic railway vehicle brake equipment and comprising: a. first means normally charged to a predetermined fluid pressure and operative responsively to a reduction of such fluid pressure therein for causing a brake application on the vehicle commensurate with the degree of reduction; b. second means normally charged with fluid pressure at a degree corresponding to said predetermined fluid pressure; c. operator''s means selectively operable to a plurality of positions for initiating a reduction of fluid pressure in said second means to a selected reduced degree according to the position to which said operator''s means is operated, d. said operator''s means including relay valve means operable responsively to reduction of fluid pressure in said second means to a degree corresponding to the degree of fluid pressure prevailing in said first means at the time said reduction is initiated, for effecting reduction of pressure in said first means to said selected reduced degree; and wherein the improvement comprises: e. indicating means cooperatively responsive to reduction of fluid pressure in said first and second means for indicating the pressure differential between the initial pressure prevailing in said first means at the onset of said reduction and the final pressure prevailing therein at termination of such reduction.
Claim 3
Dependent Claim
20 words
Brake pipe reduction indicating apparatus, as set forth in claim 1, wherein said first means comprises a train brake pipe.
Claim 4
Dependent Claim
19 words
Brake pipe reduction indicating apparatus, as set forth in claim 2, wherein said second means comprises an equalizing reservoir.
Claim 5
Dependent Claim
152 words
Brake pipe reduction indicating apparatus, as set forth in claim 3, wherein said indicating means comprises: a. a differential pressure gauge having a high pressure side normally in communication with said equalizing reservoir and a low pressure side constantly in communication with said brake pipe; b. a fluid pressure reference volume normally in communication with said equalizing reservoir; and c. valve means having a normal position in which said communication of said equalizing reservoir with said reference volume and with said high pressure side of the gauge are in effect, d. said valve means being operable responsively to the onset of reduction of fluid pressure in the brake pipe, to a differential position in which communication of said equalizing reservoir is cut off from both the reference volume and the high pressure side of said gauge, and said reference volume is placed in communication with said high pressure side of said gauge.
Claim 6
Dependent Claim
113 words
Brake pipe reduction indicating apparatus, as set forth in claim 4, wherein said valve means further comprises: a. a switch-over valve device; b. biasing means for biasing said switch-over valve device toward said normal position; c. a fluid pressure operable pilot valve effective, when actuated, for operating said switch-over valve device to saId differential position; d. electrical solenoid means including electrical circuitry effective, when energized, for actuating said pilot valve; and e. a fluid pressure operable electrical switch device interposed in said electrical circuitry and operable responsively to fluid pressure diverted from said brake pipe at the onset of said reduction of fluid pressure therein for effecting energization of said electrical solenoid means.
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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |