US1876013A - Railway braking apparatus - Google Patents

Description

J. w. LIVINGSTON RAILWAY BRAKING APPARATUS Filed Sept. 2, 1931' Sept. 6, 1932.

INVENTOR. UT WAN/N77525:),

.Qji N 1 ATTORNEY.

RF SQ lllllllllllllllll Patented Sept. 6, 1932 warren STATES PATENT oerica JOHN W. LIVINGSTON, F WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE UNION- SWITCH 'z SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA RAILXVAY BRAKING APPARATUS Application filed September 2, 1931. Serial No. 560,717. Y

My invention relates to railway braking apparatus, and has for an object the provision of means for automatically controlling the braking action of a car retarded in accordancewith the speedof a car passing therethrough. Specifically, the present invention is an improvement on apparatus of the type disclosed and claimed in an application for Letters Patent. of the United States,

filed by Herbert L. Bone on July 9, 1931, Serial No. 549,588, for railway braking apparatus. V r

I will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims. 7

The accompanying drawing is a diagrammatic view illustrating one form of apparatus embodying my invention.

Referring to the drawing, the reference characters 1 and 1 designate the track rails of a stretch of railway track over which cars normally move in the direction indicated by the arrow under such conditions that it is desirable to control the speed of the cars.

"F or example, the stretch of track here shown might be in a classification yard of the hump type through which cars move under the influence of gravity. It is obvious that in service of this character, the speed of "individual cars or strings of cars will vary through wide limits depending, among other things, upon the speed at which they go over the hump, the temperature, the weight of the and contents, and the condition of the lull 'car as to whether itis a .free running car or otherwise.

In order to control the speed of cars, the stretch of track shown in the drawing is comprising, in the form illustrated, a pair of braking bars 2 and 3, extending parallel with, and located on opposite sides of rail 1, and a similar pair of braking bars 2 and 3 extending parallel with, and located on opposite sides of rail 1*.

The braking bars 2, 3, 2 and 3 are operated by a fluid pressure motor M comprising B a cylinder 4 containing a reciprocable pis-' ton 5 which is attached to one end of a piston rod 6. The braking bars 2, 3, 2 and 3 are operatively connected with the piston rod 6 of motor M through suitable linkage in.-

cluding a bell crank 7 pivotally supported at c point 8, and a lever 9 'pivotally supported at polnt 10., Whenpiston 5 of motor M occupies its extreme right-hand position, in which it is illustrated in the drawings, the braking bars 2, 3, 2 and 3 occupy theirineffective or non-braking positions in which they are out of engagement with the wheels of a car traversing rails 1 and 1''.-' When piston 5 is moved to its left-hand position, however, as when fluid. pressure is admitted to the rightiand end of'cylinder 4;,the braking bars 2, 3, 2 and 3 are moved toward the associated rail to their effective or braking positions in which they vwill engage the wheels of a car traversing the rails 1 speed of the car.

and 1 to retard the The motor M is controlled by two magnet valves A and B, each comprising avalve stem ll'biased to an upper position by means of a spring 12, and each provided with a winding 13and an armature 14. When winding 13 of valve A is deenergized,valve stem 11 is moved to its upper position by spring 12, and under these conditions, the left-hand end of cylinder 4 is connected with atmos phere through a pipe 15 and a port 16. When winding 13 of this valve is energized, however, as illustrated in the drawing, valve stem 11 is moved downwardly todisco-nnect pipe 15 from port 16,-and to connect-this pipe with a suitable source of fluid pressure, not

shown in the drawing, through a pipe 17.

When winding 13 of valve A is energized,

therefore, the fluid pressure supplied to the left-hand end of cylinder 4 moves piston 5' toward the right, thereby moving the braking bars to their non-breaking positions. I

When winding 13 of valve B is deenergized as shown in the drawing, valve stem 11 of this valve is moved to its upper position, i and the right-hand end of cylinder 4 is then connected with atmosphere through a pipe;

18 and a port 19. When winding 13 of valve is energized, however, valve stem 11 of this valve moves downwardly, disconnecting 4 pipe 18' from port 19, and connecting pipe 18 with pipe 17 It will be apparent, therefore, that when valve B is energized, piston 5 is urged toward the left to move the braking bars to their effective positions by a force which is proportional to the pressure of the fluid supplied to the right-hand end of cylinder 4 under these conditions.

The reference character P designates acircuit controller comprising a Bourdon tube 20, connected with pipe 18, and subjected to thepressure in the right-hand end. of cylinder 4, I The Bourdon tube 20 controls a contact 21 which is closed at all times except when the pressure exceeds a predetermined amount, such for example, as'thirty pounds per square inch, which-pressure is preferably enough to cause the braking bars to exert sufiicient braking force to slow down a light weight or medium weight car to the lowest speed at which it is desired to have such car leave the retarder, provided the speed at which the car enters the retarder is within the normal operating limits. Circuit icontroller P is similar to circuit con troller P except that contact 21 of this circuit controller is arranged to open at a higher pressure than contact '21 of circuit controller 1 For example, the parts may be so proportioned that contact 21 of circuit controller P will be closed for all pressures below eighty pounds per square inch, but

will be open for all pressures above eighty pounds per square inch, this latter pressure being sufiicient to cause the braking bars to retard a heavy car the desired amount as the car passes through the retarder provided the speed at which the car is moving when it enters the retarder is within the normal oper-' ating limits.

The valve B is controlled by the circuit controllers P and P by amanually operable'lever L, and by a control relay C. The manually operable lever L, in the form here shown, is capable of assuming three positions, indicated by. dotted lines in the drawing, and designated by the reference characters p, p and 12 respectively. Opera'- tively connected with lever L are two contact arms 22 and 23. The contact arm 22 cooperates with a contact segment 24 to close a contact 22-24 when lever L occupies either its or p position, or any position intermediate these two positions. 2 The contact arm 23 cooperates with three fixed contacts 25, 26 and 27 to close a contact 23-25, 23-26,

or 23-27, according as lever L occupies its 39, 19, or p position, respectively.

The lever L and relay 0 in addition to controlling the valve B' also control the valve A.

As shown in the drawing, lever L occupies its 10 position, and relay C is'deenergized. Under these conditions, all circuits for, valve B are open and a circuit is completed for valve A which passes from a suitable source of current, here shown as a battery D, through contact 23-25 of lever L, wire 39,

winding 130i valve A, and wires 38 and 33 If, now, with relay C remaining deenergized, lever L is moved to its 9 position,

the circuit just traced. for relay A will become interrupted'at contact 23-25 of lever L, and a circuit for valve B will become closed at contact 23-26 of lever L, this latter circuit passing from battery D through contact 23- 26 of lever L, wire 28, back contact 29-29 of relay C, wire 30, contact 21 of circuit con-. troller P wires 31 and 37 winding 13 of valve. B, and wires 32 and 33 back to battery D. As a result, valve A will become deen-' ergized and will vent the left-hand end of cylinder 1 to atmosphere, and valve B will be come energized and will admit fluid to the right-hand end of the cylinder until the pressure in this end of the cylinder exceeds thirty pounds per square inch, at which time contact 21 of circuit controller P will open and will deenergize valve B until the pressure again decreases below thirty pounds per square inch. It will be apparent, therefore, that when lever L occupies its 19 position, and relay C is deenergized, the braking bars will be held initheir braking positions by a pressure of approximately thirty pounds per square inch, which pressure, as previously pointed out, is normally sufficient to cause the braking bars to slow down a light weight or medium weight car to the slowest speed at which it is desired to have the car leave the retarder.

If, when lever L occupies its p position, relay C becomes energized, the circuit just traced for valve B will become interrupted at back contact 29-29 of relay C, and another circuit for valve A will become closed which passes from battery D through contact 23- 26 of lever L, wire 28, front contact 29-2? of relay C, wires 40 and 39, winding 13 of valve A, and Wires 38 and 33 back to battery D. Valve B will therefore become deenergized, and valve- A will become energized. As a result, the braking bars will be moved to their ineffective or non-braking positions in a manner which will be readily understood from the foregoing, and from an inspection of the drawing.

If lever L is moved'to its p position when relay C is denergized, all circuits for valve A will be open, and a circuit for valve B will become closed which passes from battery D through contact 23-27 of lever L, wire. 34, back contact 35-35 of relay C, wire 36, contact 21 of circuit controller P wire 37, winding 13 of valve B, and wires 32Iand 33 back to battery D. Under these conditions, valve A will be deenergized and valve B will be come energized and will admit fluid to the right-hand end of cylinder 4.until the pressure in this end of the cylinder exceeds eighty pounds per square inch, at which time contact 21 of circuit controller P will open, and will deenergize valve B until the pressure again decreases below eighty pounds per square inch. It will be apparent, therefore, that under these conditions, the braking bars will be held in their braking positions by a pres sure of eighty pounds per square inch, which pressure, as previously pointed out, is normally sufficient to cause the braking bars to slow down a heavy car to the slowest speed at which it is desired to have the car leave the retarder.

If relay C becomes energized when lever L occupies its p position, the circuit last traced for valve B will be interrupted at back contact 3535 of relay C so that valve B will become deenergized, and a third circuit for valve A will become closed at front contact 35-35 of relay C. This third circuit for valve A passes from battery D through contact 2327 of lever L, wire 34, front contact 35-35= of relay C, wires 41, 40 and 39, winding 13 of valve A, and wires 38 and 33 back to battery D. Due to this third circuit, valve A will become energized, and since valve B is now deenergized, the braking bars will be moved to their non-braking positions.

It will be apparent from the foregoing that when lever L occupies its 19 or 19 position, the braking bars will occupy their braking or non-braking positions according as relay C is deenergized or is energized. According to my present invention, I provide means for controlling relay C in such manner that this relay will normally be deenergized, but that this relay will become energized if the speed of a car which is being retarded by the retarder decreases below a selected one of a plurality of speeds. As here shown, these means for controlling relay C comprise a plurality of treadles 42 42 43 and 43 In the particular embodiment illustrated, the treadles 42 and 42 are located betweenthe rail 1 and the braking bar 2 adjacent the entrance and leaving ends, respectively, of the retarder, and are so arranged that each of these treadles will be depressed by each wheel of a car running on rail 1 The treadles 43 and 43 are located opposite the treadles 42 and 42*, respectively, between the braking bar 3 and the rail 1, and are so arranged that each of these treadles will become depressed by each car wheel running on raill. Each of the treadles 42, 42 43 and 43 may be of the usual spring biased type, and will return to its normal position as soon as the car wheel'has departed from the treadle. The lengths of the treadles 42" and 42 may be varied as conditions require, but the lengths,

of these treadles will usually be equal and will preferably be lessthan half the distance between adjacent car wheels on the same car truck; The lengths of the treadles 43 and 43 will also usually be equal, but each of these latter treadles will preferably be shorter than the opposite treadle 42, and will be so arranged that it will become depressed short- 1y before the opposite treadle 42 returns to its normal position, but will return to its normal position at the sam instant or immediately before the opposite treadle 42 returns to its normal position. a contact 44 which, as here shown, is normally open, but which is arranged to'become closed when treadle 42 becomes depressed, and to subsequently remain closed until this treadle returns to its normal position. The treadle 42 similarly controls a contact45 which is normally open, but which becomes closed when the treadle 42 becomes depressed and subsequently remains closed until this treadle returns to its normal position. It will be apparent, therefore, that the time in terval during which the contacts 44 and 45 are closed when a car wheel is passing the associated treadle 42 or 42 will depend upon the speed of the car. The treadle 43 controls a contact 46 in such manner that this.

contact will. be closed when the treadle occupies its normal position but will become open when this treadle becomes depressed, and the The treadle 42 controls treadle 48 controls a contact 47 in a similar 7 The means for controlling relay C also com prises a plurality of timing relays T and T which, as here shown, have slow pick-up characteristics. The timing relays T and T are 1 connected with a pair of line Wires 59 and60 over the contacts 44 and 45, respectively, and

the line wires 59 and 60, in turn, are connected with a suitable source of energy, here shown as a battery E, through a rheostat F. It will be apparent, therefore, that if the arm 48 of rheostat F engages any of the taps of the rheostat except the off tap 61. when a car'wheel depresses oneof the treadles 42 or 42*, the timing relay T controlled by such treadle will become energized and will re main energized for a time interval which depends upon the speed of the car. I If this time interval is longer than the pick-up time for such relay T, this relay will close its armature, thus closing its front contact'49, but if this time interval is shorter than the piclpup time for such relay T, the armature of the relay, and hence, the contact 49 controlled thereby, will 7 remain open.

and T are so constructed that their pick-up time may be increased or decreased by decreasing or increasing their energization, and it follows that by moving the arm 48 of The relays T' rheostat F toward the left, the car speed at V which these relays will pick up mayhemcreased, there being as' many dilferent'car speeds as there are different taps on the rheostat. The parts are preferably so proportioned, that when the arm 48 of rheostat F is engaging the tap in which all the resistance of the rheostat F is cut in, the relays T and T will pick up their armatures when a car which is being retarded by the retarder is moving at the slowest speed at which it is desired to have cars leave the retarder.

The rheostat F, which functions as a speed controller, and the lever L which controls the braking force exerted by the braking bars, will usually be located adjacent each other in a control cabin in such positions that they can be conveniently operated by the same operator.

Relay C is provided with two pick-up circuits each of which includes .a suitable source of current here shown as a battery G, and a front contact 49 of a different one of the relays T. It will be apparent, therefore, that if either of the relays T or T becomes energized for a suflicient interval of time to close its front contact 49, relay C will also become energized. 7 7

Relay C is further provided with a stick circuit which passes from battery G through wires 50 and 51, contact 2224 of lever L,

wire 52, front contact 53 of relay C, wire 54, contact 46, wire 55, contact 47, wires 56, 57 and 58, and the winding of relay C back to battery G. It will be noted that this stick circuit is closed when and only when lever L occupies its 39 or 19 position, the treadles 43" and 43 both occupy their normal position, and relay C is energized. I As shown in the drawing, arm 48 of'rheostat F occupies the position in which all of the resistance of the rheostat is cut in. Relays T and T are both deenergized, and both pick-up circuits for relay C are therefore open. The stick circuit for relay C is also open, and relay C is therefore deenergized. Lever L occupies its 79 position. The braking bars therefore occupy their nonbraking positions in which they are out of engagement with the wheels of a car traversing the stretch of track shown in the drawing.

In explaining the operation of the apparatus as a whole, I will assume that a car which is travelling at a relatively high speed is approaching the retarder, and that it is desired to have the car leave the retarder at a predetermined reduced speed. The operator will therefore first move the braking bars to their braking position by moving lever L to its 12 or position, depending upon the weight of the car, and he will then move arm 48 of rheostat F to the position which will cause the relays T to close their front con.- tacts' 49 at the particular speed at which it is desired to have the car leave the retarder,

which speed I will term control speed. As the car moves through the retarder, each of the treadles 42, the associated relay T will close its front contact- 49, and relay C will then become energized. WVhen relay 0 becomes energized, the braking bars will be moved to their non-braking positions in the manner previously described, and it will be apparent, therefore, that no further retardation of the car will take place as long as relay C remains ener ized. Relay C will re-. main energized untfilever L is restored to its p position, unless the car again attains a speed which is greater than control speed before the car has :departed entirely from the retarder. For, as long as the speed of the car is below control speed and contact 22-24 of lever L is closed, if no wheel of the car is depressing one of; thetreadles 43" or 43,. the stick circuit previously described for relay C will be closed, and if a wheel of the car is depressing one of the treadles 43, so

that the stick circuit previously described' for relay C is open, then one of the pick-up circuits for relay C will be closed at the front contact 49 of the relay T which is controlled by the treadle 42 which is opposite the depressed treadle 48. Assuming, however, that the car again attains a speed which is greater than control speed before the car has departed entirely from the retarder,-,then as soonas a car wheel depresses one of the treadles 43, the stick circuit for relay C will become interrupted, and the front contact 49 of both relays T will then be open so that both pickup circuits for relay C will be open, and as a result, relay G,,will become deenergized.

When relay G becomes deenergized, the braking bars will, of course, again be moved to their braking positions to again retard the car. It will be seen, therefore, from the fore going, that with apparatus embodying my invention, the braking action of the retarder will automatically be controlled in accordance with the speed of the car, and the car er than control speed depresses contact 43.

When lever L is restored to its p position, the stick circuit for relay C will become inter- C will then become tions, in whichthey are illustrated in'the drawing. i 7

If the operator desires to retain complete manual control of the retarder, he may do :so by moving arm 48 of rheo'stat F into engagement with the ofi tap 61. When arm 48 occupies this latter position, the relays T and T will not become energized [when the treadles 42 and 41-2 C will therefore remain deenergized regardless of the speed of the car. It will be apparent, therefore, that under these conditions, the braking bars will always occupy the positions corresponding to the setting of lever L.

One advantage of railway braking apparatus embodying my invention is that it provides an extremely simple and efiective means for controlling the braking action of a car rctardcr in accordance with the speed of cars which are being retarded bythe retarder.

Although I have herein shown and described only one form of railway brakingapparatns e bodying r y invention, it is understood that various changes and modifications may be made therein within the scope of the I appended claims without departing from the spirit and scope of my invention. i Having thus described my invention, what I claim is: i

1. Railway braking apparatus compr sing a braking bar located in the trackway adjacent a track rail, a first relay, means controlled by said'first relay for controlling sald braking car, a plurality of other relays,means controlled by each of said other relays for controlling said first relay; devices disposed in pairs along the trackway, the devices of each pair being so arranged that the first device will become operated each time a car wheel passes a first fixed point and will be restored to its normal condition when the car wheel passes a second fixed point located a measured distance in advance of said first fixed point and that the second device will become operated each time a car Wheel passes a third point intermediate said list and second points and will be restored to its normal condition when the car wheel passes said second point, means controlled by saidfirst device of each pair for controlling a different one of said other relays, and means controlled by all of said second devices for controlling said first relay.

2. Railway braking apparatus comprising a braking bar located in the trackway; a pluralitv of devices disposed in pairs along the tracliway, the devices of each pair being so arranged that the first device will become operated each time a car wheel passes a first fixed point and will be restored to its normal condition when the car wheel passes a second fixed point located a measured distance in second device will a car wheel passes said first and second points and "will be re-" are depressed, and relay plurality "of advance of said first fixed point and that the a third point intermediate stored to its normal condition when the car wheel passes said second point, a plurallty of relays one controlled by said first device of each pair and each arranged to become enerbecome operated each time gized when theassociated device is operated, 52

a control relay, means for energizing said control relay when any of the other relays is energized, other means for energizing said control relay effective when and only when said control relay said'second device of each pair occupies its normal condition, and meanscontrolled by said control relay for controlling said braking bar. 7 V

3. Railway braking apparatus comprising a braking bar located in the trackway, a plurality of devices disposed in pairs along the trackway, the devices of each pair being so arranged that the first device will become operated each time fixed point and will be restored to its normal condition when the car wheel passes asecond fixed point locateda measured distance in advance of said first'fixed point and that the second device will become operated each time a car wheel passes a third point intermediate said first and second points and will be restored to its normal condition when the car wheel passes said second point, a plurality of timing relays one controlled by said first device of each pair and each arranged to become energized when the associated device is operated, a control relay, means for energizing said control relay when any one of said timlng' relays is energized, other means for energizing said control relay efiective when and only when said control relay has once been energized and said second device of each pair occupies its normal condition, and means for moving said braking bar to a braking or a non-braking position according as said control relay is deenerglzed or energized.

4 Railway braking apparatus comprising a braking bar located in the trackway adja-, cent a track ra1l, a pressure responsive device for moving said braking bar into position to engage apart of a car to retard the speed of the vcar, a first relay, means controlled in part by said firstrelay for supplying pressure 7 to said pressure responsive device, a plurality oftinnng relays, means controlled by each of said timing, relays for controlling said first relay, a plurality of along thetrackway, being so arranged that the first device will, become operated; each time a car'wheel passes a firstfixed point normal condition when the car wheel passes a second fi ed point located a measured distance in advance the second device will be operated each time a has once been energized and a car wheel passes a first devices disposed in pairs I the devicesof'each pair and will be restored to its 7 of said first pointand that trackway,

i vice is operated, a plurality of timing relays carwheel passes a third point located intermediate s aid first and second points and will be restored to its normal condition when the 'car wheel passes said second point, a plural- 5 ity of contacts one controlled by each of said devices, means controlled by each of the con tacts which are controlled by said first devices for controlling a difierent one of said other relays,and means controlled by all of 10 the contacts which are controlled by said second devices for controlling said first relay.

' 5. Railway braking apparatus comprising i a braking bar located in the trackway adj acent a track rail, a pressure responsive device fixed point located a measured distance in advance of said first point and that the second device will become operated each time a third point located inter:

car wheel passes a mediate saidfirst and second points and will be restored to its normal condition when the car wheel passes said second point, a plurality of contacts one controlledby each of said devices and each arranged to be operated during theentire time that the associated deone controlled by each of the contacts which are controlled by said first devices, and means controlled by each of said timing relays and by all of the contactswhich are controlled by said second devices for controlling said first relay.

6. Railway braking apparatus comprising a braking bar located in the trackway adja 4 cent a track rail, a pressure responsive de- 1351 vice for moving said braking barinto position to engage a part of a car to retard the speed of the car, a first relay, means controlled in part by said first relay for supplying pressure to said pressure responsive de- 5 vice, a plurality of devices disposed in pairs along the trackway, the devices of each pair being so arranged that the first device will become operated each time a car wheel passes a first fixed point and will be restored to its normalcondition when the car wheel passes a second fixed point located a measured distance in advance of said first point while the second device will be operated each time a car ing the entire time that the associated device is operated, a plurality of other relays,

means controlled by each ofvthe contacts which are controlled by said first devices for controlling a different one of said other relays, a pluralityof pick-up circuits for saidfirstrel'ay each controlled by a contact of a different one of said other relays, and a stick circuit for said first relay including its own front contact and all of the contacts which are controlled by said second devices.

7. Railway braking apparatus comprising a braking bar located in the trackway, a control relay, means 'for moving said braking bar to a braking or a non-braking position according as said control relay is deenergized 0r energized; a plurality of devices disposed in pairs along the trackway, the devices of each pair being so arranged that the first device will become operated each time a car wheel passes afirst fixed point and will be restored to its normal condition when the car wheel passes a second fixed point locateda measured distance in advance of said first fixed point. and that the second device will become operated each time a car wheel passes a third point intermediate said first and second points and will be restored to its. normal condition when the car wheel passes said second point; a plurality of normally open contacts, one controlled by said first device of each pair and each' arranged to become closed when the associated device is operated and to remain closed until the associated device is restored to its normal condition, a plurality of timing relays; a circuit for each of said timing're-' lays including a source of current, a rheostat and a different one of said normally open contacts; a plurality of pick-up circuits for said control relay each'controlled by a front contact of a different oneofsaid timing relays, a plurality of normally closed contacts one controlled by said. second device of each pair andeach arranged to become opened when the associated device is operated and to remain open until the associated device is restored to its normal condition, and a stick circuit forsaid control relay including its own front contact and all of said normally closed contacts. r

In testimony whereof I affix my signature.

JOHN W. LIVINGSTON.

60 wheel passes a third point located interme- 'idiate said first and second points and will be restored to its normal condition when the car wheel passes said second point, a plurality of contacts, 'one controlled by each of said de Q vices and; eacharranged to be operated edur

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