US3901558A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pneumatic/electro-pneumatic interlock circuitry for double-end control locomotive
Assignee: Westinghouse Air Brake Co
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Filing: 1974-08-26
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Granted: 1975-08-26
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Expires: 1994-08-26
Abstract
Abstract A pneumatic/electro-pneumatic interface unit for providing safe brake control of a train having a locomotive arranged for doubleend control. The interface unit includes means for sensing different operating conditions of the pneumatic brake valve device at each control station. The sensing means acts through interlock circuitry to assure that power is supplied only to the mastercontroller comprising the electro-pneumatic brake control means at the control station having the cut-in brake valve device, provided the brake valve device at the noncontrolling station is in its cut-out condition and is in handle-off position. With power supplied, the mastercontroller is enabled to control energization of brake application and release relays, which in turn control energization of the application and release train wires, according to the operating condition of the controlling brake valve device. In the event both brake valves are cut out and are in a handle-off position, additional interlock circuitry is provided to cut off power to each mastercontroller and instead connect power directly to the brake application relay to assure application of the train brakes independent of either mastercontroller.
Inventors
- 👤 Richard O Burkett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:49
CPC Classifications
B; B60; B60T; B60T15/00; B60T15/02; B60T15/04; B60T15/16; B60T13/00; B60T13/10; B60T13/66; B60T13/665
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
390 words
In a train having a locomotive with a control station at each end, a combined pneumatic and electro-pneumatic brake control system including: a. a brake pipe extending through the train, the pressure variation carried in said brake pipe controlling the train brakes; b. an equalizing reservoir at each control station; c. a brake valve at each control station comprising: i. an operating handle movable from a brake release position through a brake application zone, in which said equalizing reservoir at the same control station is charged with fluid pressure according to the position of the handle in the brake application zone, to a handle-off position and an emergency position; ii. relay valve means subject to said equalizing reservoir pressure at said same control station for controlling the fluid pressure in said brake pipe; and iii. cut-off valve means operable to establish a cut-out condition of said brake valve by interrupting the variation of pressure in said brake pipe by said relay valve means; and d. a mastercontroller device at each control station subject opposingly to said brake pipe pressure and said equalizing reservoir pressure at the same control station, and having a normally open application switch and a normally open release switch, one or the other of which is actuated when a pressure differential arises between said brake pipe and equalizing reservoir pressures, depending upon the sense of said pressure differential; e. a brake application wire extending through said train to provide electrical control of pressure in said brake pipe so as to effect variation thereof in a first sense; f. a brake release wire extending through said train to provide electrical control of pressure in said brake pipe so as to effect variation thereof in a sense opposite said first sense; g. a source of electric power; and h. interlock means for establishing a first circuit via which electric power is connected from said source to said mastercontroller at one of said control stations only when said brake valve thereat is cut in and said brake valve at the other control station is cut out and is in handle-off position, thereby to enable said mastercontroller at said one of said control stations to control energization of said application and release wires via said application and releAse contacts according to the sense of said brake pipe/equalizing reservoir pressure differential thereat.
Claim 2
Dependent Claim
390 words
In a train having a locomotive with a control station at each end, a combined pneumatic and electro-pneumatic brake control system including: a. a brake pipe extending through the train, the pressure variation carried in said brake pipe controlling the train brakes; b. an equalizing reservoir at each control station; c. a brake valve at each control station comprising: i. an operating handle movable from a brake release position through a brake application zone, in which said equalizing reservoir at the same control station is charged with fluid pressure according to the position of the handle in the brake application zone, to a handle-off position and an emergency position; ii. relay valve means subject to said equalizing reservoir pressure at said same control station for controlling the fluid pressure in said brake pipe; and iii. cut-off valve means operable to establish a cut-out condition of said brake valve by interrupting the variation of pressure in said brake pipe by said relay valve means; and d. a mastercontroller device at each control station subject opposingly to said brake pipe pressure and said equalizing reservoir pressure at the same control station, and having a normally open application switch and a normally open release switch, one or the other of which is actuated when a pressure differential arises between said brake pipe and equalizing reservoir pressures, depending upon the sense of said pressure differential; e. a brake application wire extending through said train to provide electrical control of pressure in said brake pipe so as to effect variation thereof in a first sense; f. a brake release wire extending through said train to provide electrical control of pressure in said brake pipe so as to effect variation thereof in a sense opposite said first sense; g. a source of electric power; and h. interlock means for establishing a first circuit via which electric power is connected from said source to said mastercontroller at one of said control stations only when said brake valve thereat is cut in and said brake valve at the other control station is cut out and is in handle-off position, thereby to enable said mastercontroller at said one of said control stations to control energization of said application and release wires via said application and releAse contacts according to the sense of said brake pipe/equalizing reservoir pressure differential thereat.
Claim 3
Dependent Claim
54 words
The system as recited in claim 1, further comprising interlock means for establishing a second circuit to which said source of electrical power is connected to control energization of said application wire only when said brake valve at each of said control stations is in said cut-out condition and is in said handle-off position.
Claim 4
Dependent Claim
40 words
The system as recited in claim 2, further comprising interlock means for establishing a third circuit to which said source of electric power is connected to control energization of said application wire only when an emergency brake application is made.
Claim 5
Dependent Claim
150 words
The system as recited in claim 3, further comprising: a. said brake application and release wires having a constant connection with said source of electrical power; b. a brake application relay connected to said application switch of said mastercontroller at each of said control stations and to said second and third circuits for energization thereby, and having a normally open contact in said application wire to interrupt energization thereof except when said application relay is energized; and c. a brake release relay connected to said release switch of said mastercontroller at each of said control stations, and having a normally open contact in said release wire to interrupt energization thereof except when said release relay is energized, said application relay having a normally closed contact in said release wire in series with said normally open contact therein to prevent energization of said release wire whenever said application relay is energized.
Claim 6
Dependent Claim
32 words
The system as recited in claim 2, further comprising three-way switch means for controlling application of electric power from said source to said brake control system from either of said control stations.
Claim 7
Dependent Claim
46 words
The system as recited in claim 5, further comprising an indicator light at each of said control stations connected in parallel with said first and second circuits for providing a visual indication of when said three-way switch means is providing power to said brake control system.
Claim 8
Dependent Claim
29 words
The system as recited in claim 6, further comprising diode means for preventing the feedback of energizing current from one of said first and second circuits to the other.
Claim 9
Dependent Claim
158 words
The system recited in claim 1, further comprising: a. pneumatic AND logic means subject at one input to a fluid pressure signal provided when said brake valve at said other control station is in said handle-off position and subject at the other input to a fluid pressure signal provided when said brake valve at said other control station is in said cut-out condition; and b. said interlock means including: i. a first pressure switch operable responsive to a fluid pressure signal provided when said brake valve at said one control station is in said cut-in condition to effect closure of a first contact in said first circuit; and ii. a second pressure switch operable responsive to a fluid pressure signal provided by said pneumatic logic means when a fluid pressure signal is present at both said one and said other inputs thereof to effect closure of a second contact in said first circuit to complete said first circuit.
Claim 10
Dependent Claim
129 words
The system recited in claim 2, further comprising: a. first and second AND logic means each operative to provide a fluid pressure output signal responsive to a respective one of said brake valves being in said handle-off condition in which a fluid pressure signal is provided at one input of said logic means and in a cut-out condition in which a fluid pressure signal is provided at the other input; and b. said interlock means via which said second circuit is established including first and second pressure switches operable responsive to said fluid pressure output signal provided by a respective one of said first and second logic means, to effect closure of a first set of contacts of said first anD second pressure switches to complete said second circuit.
Claim 11
Dependent Claim
121 words
The system as recited in claim 3, further comprising: a. means for sensing an emergency rate of reduction in the pressure of said brake pipe; b. a double check valve having one input subject to a fluid pressure signal provided by said emergency sensing means, another input subject to a fluid pressure signal provided by either one of said brake valves when moved to said emergency position, and an output for providing a fluid pressure signal when either one of said inputs thereof is pressurized; and c. said interlock means for establishing said third circuit being a pressure switch operable responsive to said output signal from said double check valve to effect closure of a contact to complete said third circuit.
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 |