US1875853A - Railway traffic controlling apparatus - Google Patents

Description

J. P. COLEMAN RAILWAY TRAFFIC CONTROLLING APPARATUS Sept. 6,- 1932.

Original Filed April 25. 19:50

' 4 Sheets-Sheet l INVENTOR J? P. Coleman,

Sept. 6, 1932. COLEMAN 1,875,853

RAILWAY TRAFFIC CONTROLLING APPARATUS Original Fil ed April 25, 1930 4 Sheets-Sheet 2 INVENTOR 1 9 I I PCo/emqn,

Sept. 6, 1932. J p COLEMAN 1,875,853

RAILWAY TRAFFIC CONTROLLING APPARATUS Original Filed April 25, 1930 4 SheetsSheet 4 III y- 9. NToR;

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ALL/ a Patented Sept. 6, 1932 UNITED STATES PATENT OFFICE JOHN P. COLEMAN, OF FIDGEWOOD, PENNSYLVYAN'IA, ASSIGNQR TO THE UNIQN SWITCH; & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF BENNSYIE VANIA RAILWAY TRAFFIC} CONTROLLING APPARATUS Application filed April 1930, Serial No. 447,155. Renewed February 16, 1932'.

My invention relates to railway traflic controlling apparatus andhas particular relation to apparatus of the type in which a rail way switch is moved between normal and reverse positions by amanually operable lever through the medium of a valve controlled fiuid pressure motor.

One of the features of my invention is the provision, in apparatus of the type described, of means for limiting the movement of the lever unless both the valve and the switch occupy predetermined positions relative to each other.

Another feature of my invention is the provision of a contact device operated by the valve mechanism for controlling the energization of an indication relay jointly with the switch operated circuit controller, thereby eliminating the necessity of the quick switch usually employed for controlling the operation of the lever mechanism.

I will describe'one form of railway traflic controlling apparatus embodying my invention, and will then point out the novel fea-- tures thereof in claims. V I. In the accompanying drawings, Fig.1 is

a diagrammatic view, illustrating one form of railway traflic controlling apparatus em-' bodying my invention. Fig. 2 is a front elevational view with part broken away of the valve mechanism and contact device shown in Fig. 1'. Fig. 3 is a vertical sectional ilar parts in each of the several'views.

Referring first to Fig. 1, my invention is diagrammatically shown as embodied in rail way tranic controlling apparatus which, brief- 1y, comprises a valve mechanism A; a contact device B directly associated with and operated by the valve mechanism for controlling the position of the valve according to the position of other elements of the apparatus; a fluid pressure motor Q controlled by the valve mechanism a track switch 1):, I

movable between normal and reverse positions by the fluidpressure motor a pole changing device E, actuated by the movement of the switch; and a lever ,mechanism F for controlling theope'ration of the valve mechanism. The construction and operation of'the above mentioned instrumentalitiea'together with the manner in which they cooperate to obtain the endin. view, will now'be described in'the order indicated.

The valve mechanism A (Fig. 2) comprises a main casting l which is formed with a plurality of feet or pedestals 2 for connec* tion with a suitable'support (not shown) The casting lis formed with a constantpres sure chamber 5 (Fig. 5) in the lower portion thereof into which access may be obtained through spaced openings in the bottom of; the casting which openings are normally closed by screw caps or plugs (B -6 A pair of axially arranged screw threaded openings 7 7 (Fig. '2) communicate with the cham? her 5 through a tubular air screen 8 connecting these openings within the chamber, and a pipe 9 may be connected with either ofthese openings in order to establish communica tion between the'chamber 5 and a sourceof" constant air pressure according to the position of the device relative to the track. The opening not so employed is closed by means of a screw plug 10. The chamber 5'- communicates through sleeves 11=*11 (Fig. 5') with a pair of spaced outlet chambers 152F 12) which are formed in the casting 1 directly above the chamber 5 and which communicate,

through pipes 13 18 with the switchoperating device C, presently to be described.-

- The passage of air through the sleeves 11*?- 11 is controlled by means of'valve members l4l 1l which are secured to the lower;extremities' of valve stems 15F15"; These valve stems are slidably mounted in the sleeves 1l '11 and are provided with a plurality of longitudinally extending spaced ribs or guides 16 16 "between which air passes from the chamber 5 into the outlet chambers 12"12 when the valve members 1 P14 occupy their lower, or open, positions. The valves 1 l 1 l are urged toward closed positions in which they engage valve seats 17 -17 formed on the lower ends of the sleeves 11 11 by means of coiled springs 18 -48 interposed between the valves and the caps 6 6 A pair of spaced exhaust chambers 20*20 are formed in the casting 1 above the outlet chambers 12 12 and communicate with the outer atmosphere through passageways 21 -21 (Figs. 6 and 8), ports 2323 provided-in sleeves 24 '24 which extend through the exhaust chambers 20 20 in-axial alignment with the valve stems 15 15 and with the outlet chambers 12 12'. through openings 2222 formed in the casting; The valves141l are alternately opened against the action of the springs 18- 18 in order to admit air under pressure into one side or the other'of the switch operating device C by means of the following described mechanism.

A pair of laterally spaced fluid pressure cylinders 2 5" 25 are formed in the upper portion of the casting 1 in axial alignment with the valves le -14 These cylinders are V 3O-30 for-engagement with valve seats V openings 22 -22 in spaced relation with the closed at theirv upper ends by cylinder heads 2626. but open at their lower ends into lever chambers 27 27 as best shown in Fig. 5. Pistons 28'28 are mounted for vertical reciprocation within the cylinders 25=25 and carry depending plungers or valve stems 29*29 which extend downwardly through theleverchambers 2727 and are slidably mounted adjacent their lowerends in the sleeves 24 24 I The lower extremities of the;,valve stems 29 -29 are beveled to form valve elements 31" .31 which surround the openings 22* 22 The valve stems 29 -29 are also formed at the lower ends'with reduced portions 32- 32 which are adaptedto project through the walls thereof for engagement with the upper ends of the valve stems 15 ,1 5". It will be noted by referring to Fig. 5 of the drawings that when the valves 141 l occupy closed positions and the pistons 28 -28 are elevated, communication between the constant pressure chamber5 and the outlet chambers '12 12 is interrupted and communication is established between the outlet chambers and the outer atmosphere through the openings 22?22", ports 23,23 in the sleeves2 l 24", and the passageways 21 -2l Conversely, when the valves 14 14 are opened against the action of their,springs. 18 -18 by the downward movement of the plungers 29?29 under. the influence of fluid pressure admitted to the cylinders 2525 above the pistons 28?28 communication is established between the constant pressure chamber .tions closed by ;removable 4545 Thesechambers co'mmunicatewith ly byffiuid pressure admitted above the pis- :1

tons'from the constant pressure chamber 5 in the following manner. A rearwardly extending passageway 33 (Figs. 3 and 6) establishes communication between the constant pressure chamber 5 and a valve chamber 34 provided in the rear portion of'the casting 1 and to the interior of which access maybe obtained by a removable plug 35 closingits lower end (see also F ig.7 This chamber communicates with transversely extending pas-. sageways 36and 37 (Figs. v6 and 7 through a vertically extending passageway 38, the lower end of whichmay be closed, by means of a valve member 39 to prevent the fiowof air upwardly therethrough. This valve is urged upwardly to a position in'which it seats within the lower end of the passageway 38 by a coil spring 40 disposed in the cham-- 'ber 34 between the lower end of the valve and the plug 35, valve member 39 being carried by stem 41 which extends upwardly through the passageway 38 and is operatively connected',at its upper end, with the armature of an electromagnet L, hereinafter;

41 for seating engagement with the upper end ofthe passageway 38.5When the valve39 is elevated by. the springlO inorder to interrupt communication between the chamber 34 and the passageways 36 and 37upon the deenergization ofthej locking magnet L, the valve 43 is opened thus venting passageways 1 36 and 37 to atmosphere through the exhaust Thegpassageways 36 and 37, in turn, 'com-. municate with valve chambers 4 P-44 (Fig; 7) which are alsoprovided in the rear portionof the casting 1. on each side of the chain ber 34 and to which access may also be obtained through openings in their lowerporscrew plugs forwardly extendingpassageways l6 l6 (Fig.6) through vertically extending passageways 47 4=7 which may, also be closed 1 9 beneath the cylinders 25 25 A bracket 55 46 -it6 by means of valve members 4:8fl8". These valve members are urged upwardly towards seating engagement with the lower ends of the passageways 4T l'? by coil springs dy -49 disposed within the chambers a er, between the lower ends of the valve members and the plugs l5 l5 and are carried by valve stems 50 50 The valve stems 50-50 extend upwardly through thepassageways 4:7 and operatively connected at their upper ends with the arma'tures of electroniagnets N and R, hereinafter termed the normal and reverse magnets, respectively. hese magnets are also suitably mounted on the casting 1 on each side of the lock magnet L and energized and deener ized in properly timedrelation with respect to each other and t the lock magnet L, through electric circuits hereinafter tobe described.

The upper ends of the passageways ip-47 also communicate with exhaust ports 5ll5l leading to the outer atmosphere and through which the escape of air is controlled by valve members 52"52, carried by the,

valve stems 50 -50 for seating engagement with the upper ends of the passageways 47 -4E7. As in the case of the valve l3, when the valve stems 5O-"'-5O are elevated by the springs l9 i9 in order to interrupt communication between the chambers l ll-i" and the passageways 46%16" upon the deenergizaton of the normal and reverse magnets N and R, the valves 5252 are opened,

. thus ventin passagewa s l d 16" to the atmosphere through the exhaust ports 51 5l The passageways 46 46 in turn communicate at their forward ends with vertically extending passageways 53 53 (Figs. 6 and i 9) which respectively communicate at their upper extremities with the interior of the cylinders sa er at a point above t-h pistons 28 -28 mounted therein.

U1 der normal operating conditions, for

' reasons which will appear hereinafter, it is not possible to energize the normal and re verse magnets N and R simultaneously and thereby to open valves la -14 and admit fluid pressure to opposite sides of the switch actuating device at the same time. However,

I provide against the possibility of such an abnormal condition in the following manner:

The casting 1 is also formed with a chamber 5a (Figs. 2, 8 and 4:) which houses the contact device B presently to be described and towhich access may be had through a removable cover 5 3. This chamber opens at each side into the lever chambers 27 27 arms 57. A forwardly extending shaft 58 formed with a centrally disposed opening 63 through which the lower spacing bolt 56 extends and which, although being of asize sufficient to permit of the necessary degree of angular movement of the beam under normal operating conditions, prevents abnormal swinging movement thereof in assembling the device or in the replacement of parts. The beam is also formed with a centrally disposed downwardly extending bifurcated arm ea in which a roller 65 is mounted for engagement witha detent 66. This detent is mounted for vertical sliding movement in a bore 67, in the casting 1 and is provided with a stem 68 which is slidablymounted in a removable bearing 69 threaded into the lower end of the bore 67. The detent 66 is urged upwardly into, yielding engagement witi the roller 65 by a coil spring 70 which surrounds the stem 68 between the detent 66 noted that if fluid pressure is applied above both pistons simultaneously from the chamber 5' the pistons, being of equal area, will be in a state of equilibrium by virtue of their connection through beam 60, and consequently will not move or disturb the position ofthe valves 14:-14 actuated thereby. Moreover, the detent 66, will'prevent any undesired shifting in the position of the pistons and the parts actuated thereby when there is no pressure in the cylinders 25*25 and will effectively maintain them in the positions to which they were moved whenthe device was last operated.

Thevalve mechanism above described also incorporates in its construction a contact device B for controlling the operation of the indication relay K jointly with the switch operated pole-changing device E, both of which will hereafter be described. This contact device comprisesa block 71 of insulating material (Figs. 2, 3 and 4) which is mounted on the arms 57 of the bracket 55 and which is 7 formed with, a central opening 72 through which the forward end of the shaft 58 pro valve 1 1*, the walking beam is rocked in a counter-clockwise direction, as viewed 1n Fig. 5, thereby swinging the'arm 64 to the right. This movement of the arm 6 1 carries the finger 76 into engagement with the contact 7 and breaks the circuit through thefinger 7 6' and contact 7 4". Upon movement of the walking beam 1n an opposite d1 rection the finger 7 6 moves'out of-engage' ment with its contact 74*, thereby breaking the circuit therethrough, and the finger 7 6 is carried'into engagement with its associated Contact 74*. When the contact device is actuated as above described, the detent 66 effectively maintains v the contact fingers 76 76 in the position to which they were last moved until the valve mechanism is again operated.

The contact device above described is connected in the circuit including the pole-changing device E and the polarized indication relay K and acts jointly with the pole-changing device E in opening and closing the circuit to energize and deener ize the indication relay in the eventv that the positionof the valve mechanism A does not correspond to that of the lever mechanism, track switch, and circuit controller or any one of these elementsaswill be presently described.

j The pipes 13 3 lead to the fluid pressure device C, herein shown as comprising a'fluid pressure cylinder 79 provided with a piston 80 and pistonrod 81 which is connected in'a manner well known in the art with the movable rails 82 of the track switch D, as is diagrammaticallyillustrated by the dotted line 83 in Fig. 1.

lVith particular reference to Fig. 1, it will be noted that the pipe 13 which communi cates at one end with the chamber 12 and to which the supply of fluid pressure is controlled by the normal magnet N, communicates at its other end with the cylinder 79 atthe right of the piston 80, so that when fluid pressure is admitted to the cylinder through this pipe, the switch D will be movedto its normal position. Also, it" will be noted that the pipe 13* which communicates at one end with the chambcrlQ to which the supply of fluid pressure'is controlled by the reverse magnet R, communi-.

cates at its other end with the cylinder 79 at this pipe, the switch D will be moved to its reverse position.

The switch D is operatively connected, as diagrammatically indicated by the dotted line 84 in Fig. 1, with the pole-changing device E, which comprises an arm- 85 movable be tween contacts 86 and 87 and an arm 88 movable between contacts 89 and 90. The arm 85 is connected with the positive terminal of a suitable source of power, such as battery 91, by means of a Wire 92 and the arm 88 is connected with the negative terminal of this battery by means of a Wire 93. The contact 86 is connected with one terminal of the winding 94 of a polarized indication relay 'K'by a wire 95. The other terminal of the wind ing 94 is connected with the contact 87 by means of a wire 96. The contact 89v is connected with the finger 76 of the contact device B by av wire 97 and the contact of the 7 controller is connected with the contact 74 of the contact device, by a wire 98. A wire 99'connect's the contact 74* of the contact device with the wire 96 and a wire 100 connects the finger 76 of the contact device with the wire 95. It will be apparent'that'with the parts occupying the positions shown in Fig. 1, the polarized relay K is energized by current flowing from the positive terminal of the battery, 91, wire, 92, arm 85, contact 86 of the pole-changing device E, wire 95, winding of polarized relay K, wires 96 and 99, contact 7 1 and finger 7 6 of the contact device B, wire 97, contact 89 and arm 88 of the polechanging device, and wire 93 to the negative terminal of the battery 91. Relay K is then.

energized to. close its front contact 102104 and its normal contacts 105106 and 108 109. If, however, the pole-changing device E is actuated so as to move the arms 85 and 88 into engagement with the contacts 87 and 90 respectively, as shown in dotted lines in Fig. 1, and the contact device B is actuated to open the contacts 7 6 7 4; and to close the contacts 76 74 the relay K will be enere 74", wire 98, contact 90 and arm 88 of polev changing device E and wire 93 to the negative terminal of battery 91. Relay K is then operated toclose its front contact 102-104c and. its reverse contacts 105107 and 108 110. If relay K becomes deenergized, its

front contact opens and 101'103 closes.

The lever mechanism F comprises an arm 111, movable into engagement with normal and reverse. contacts 112 and 113;: an arm 114, movable into engagement. with. normal and reverse arcuate contacts 115 and 116; an arm 117 movable into and outof engageits back contact ment with a single arcuate contact 118; and an arm 119, movable into a-nd out of engagement with a single arcuate contact 120. These arms are all mounted on a rockshaft, indicated by a broken line 12'1in Fig. 1, and are controlled by means of a manually operable lever 122. The lever mechanism F also includes a normal locking segment 123 and a reverse looking segment 124. The segment 123 is provided with a shoulder 125 for engagement with a latch 126 which is actuated by an electromagnet 127. The reverse locking segment 124 is also formed with a shoulder 128 for engagement with a latch. 129 actuated by an electromagnet 130. Thesesegments are also mounted on the shaft 121 and prevent the movement thereof under certain operating conditions. 7 I

Considering the parts in the positions shown in Fig. 1, the normal valve actuating magnet N is energized over a circuit which may be traced from a suitable source, such as battery 131, through wire 132, winding of the normal magnet N, wire 133, contact 112, arm 111, and wire 134 back to battery 131. The energization of the normal magnet N maintains the valve 48 in an open position, thereby establishing communication between the passageway 36 and the passageway 46, but inasmuch as the valve 39 is now closed by reason of the deenergization of the locking magnet L, no air pressure exists in the passageways 36 and 37 andconsequently no pressure is admitted to the cylinder 79 of the switch actuating device C by the operation of this valve alone. I

If the towerman should now desire to move the switch D from its normal to a reverse position, he swings the lever 122 in a clockwise direction until its movement is arrested in an intermediate position to the left of the vertical center line by the shoulder 128 of locking segment 124 engaging the latch 129. This movement of the lever 122 opens the circuit above traced through the arm 111 and contact 112, and deenergizes the normal magnet N. When the lever 122 is thus actuated, the arms 111, 114 and 117 are moved into engagement with their reverse contacts 113, 116 and 118, respectively, and the arm 119 into engagement with its contact 120. This establishes a circuit from battery 131, through wires 132 and 135, winding of the reverse magnet R, wire 136, contact 113, arm

111 and wire 134 back to battery 131, and another circuit from battery 131, wires 132 and 137, winding of the lock magnet L, wire 138, polar armature 105, contact 106, wire 139,

contact 116,'arm 114, wires 140 and 134, back to battery 131. These two circuits energize the reverse and locking magnets R and L respectively, and open the valves 39 and 48 of the valve mechanism, thereby admitting fluid pressure from the constant pressure chamber 5 into the passageway 37 and thence through the valve'48 into the passageways 46" and 53 From the passageway 53' the air under pressure enters the cylinder 25 and forces the piston 28 downwardly and.

the plunger .29", carried thereby, into ell-'7 F rom'the outlet chamber 12 air under pressure flows through the pipe 13 to the lefthand end of the cylinder 79 and forces the piston 80 and piston rod 81 to the left as. viewed in Fig. 1. This movement of the 5 piston shifts the switch 83, through the operative connection 82, from a normal to a reverse position.

'The downward movement of the piston 28? rocks the walking beam 60 in a clockwise directionand notonly positively lifts the piston 28 in the event that it has not pre: viously been returned to its upper position for some other reason, such as by a failure of the spring18 but also opens the circuit through the contact 74*-76 and closes the contact 74 -76 This breaks .thecircuit through the winding 94 of theindication relay K, causing its deenergization and the.

release of the neutral armatures 10'1 andi00 102.- Although "the contact device, as has been stated, acts jointly with the circuit controller in establishing or interrupting the circuit through the indication relay, it functions to interrupt this circuit before the " valve 14 or 14 isopened. This is afeature designed to deenergi'ze the indication relay prior to any action of the valve that (in tended or otherwise) will cause it toassume a.,. position out of harmony with the position of the switch and until that harmony is again restored and both coincide withthe lever in the latters original position orin its reverse position. I Y I At the commencement of the reverse movement of the switch the arms'85- and 88 of the circuit controller are moved out of engagement with the contacts 86 and 89, thereby causing-an additional break in the indication relay circuit. As soon as the reverse movement has been completedand the switch is locked in its reverse position, the arms85 and '88 of the circuit controller are moved into polarity, the neutral armature 101 moves out'leo .of engagement with its back contact 103 and the :neutral armature 102 moves into engagement 'with its front contact 104 and also that the polar armatures 105 and 108 swing outof engagement with the contacts 106 and 109 and into engagement with their contacts 107 Land 110. Themovement of the several armatures in the manner described opens the circuit through the -armature 105 and contact 106 thereby deenergizing thelock magnet L and shutting-off the supply of air pressure .to the cylinder As a result, valve 14 closes, and discontinues the supply of air pressure to cylinder 79. This movement of :the armature 108 also establishes a circuit dicatingto the leverman thatthe switch D has been fully reversed and locked, and per- Initting him to move the lever 122 through the remainder of its stroke towards its reverse position. This final movement of the energization by .a current again reversed in lever 122 carries the contact'arms 117 and 119 out of engagement with their contacts 118 and 120 and opens the circuit through the lock magnet 130.

When the leverman desires to return the switch to its normal position he swings the lever 122in a-counter-clockwise direction back to an intermediate position to the right of the vertical center line-where its movement is arrested through the engagement of the sh0ulder'125- of the normal locking segment 123 with the latch 126. In this position, the

arms 111 and 114 reengage their contacts 112 and'115 respectively, thereby completing a circuit from battery 131, Wire 132, normal magnet N, wire 133, contact 112, arm 111 and wire 134 back to the battery 131 and, also a circuit from battery 131, wires 132 and 137, lock magnet L, wire 138, polar armature 105, contact 107, wire 148, contact 115, arm 114,

- and wires 140 and 134 back to battery 131. Y The current in these two circuits energizes the normal and reverse magnets N and R, and

opens the valves 39 and 48 to admit pressure 7 above the piston 28 in the cylinder 25 and cause'the downward movement thereof. Duri ing the first part of the downward travel of the piston 28, the walking beam is rocked aboutiits axis sufficiently to open the circuit through the contacts 7 4 and 7 6 and close the circuit through the contacts 7 4 and 76 The ;ports22?, 23 and :21 and opens the valve 14 s'tant pressure chamber?) and the interiorof the cylinder 79 to the right of the piston =80, I through; the outlet chamber 12 and pipe 13'. The downward movement of the piston 28 through the medium of the walking beam 60, also elevates the piston 28 simultaneously therewith and raises the plunger 29 sufficiently to permit the valve 14 to close under 7 1 the action of the spring 18 and to establish,

communication between the left-hand end .of

the cylinder 79 and the outer atmosph re through the pipe 13 Chamber 12 and ports 30", .23 and 21 der 7 9 through the pipe 13 causes the piston 80 and piston rod 81 to; move to the left and shift the switch rails 83 back to their normal position, shown in full lines in Fig. 1.

As soonas a switch has completed this return movement and is locked in its normal position, the operative connection 84 swings the arms 85 and 88 of the pole-changing device E out of engagement with the contacts .87 and 90 back to their initial positions in engagement with the contacts 86 and 89. This, not only completes a circuit through the contacts 7 4 -=7 6 and reenergizes the magnet 94 ofthe indication relay K, but effects such polarity. This causes the neutral armatures 101 and 102 to be lifted, and the polar armatures 105 and 108 to swing back to their ini The admission of fluid 2 pressure to the right-hand end of the cylin- -against the action of the spring 18, thus establishing communication between the con the valve 39 to close under the action of its spring 40 to shut off the supply of air under 3 pressure above the piston 28, This permits the Valve 14 to close and interrupt communicationbetween the constant pressure chamber and the cylinder 79.

The upward movement of the neutral armature 102 carries it into engagement with the contact 104, thereby establishing a circuit from the battery 131, wires 132, 141 and 149, contact 120, arm 119, wire 150, lock magnet 127, wire 151, contact 109, polar armature '108, wire 145, contact 104, neutral armature 102, wires 146, 147, 140 and 134 back to battery 1.31. This causes the energization of the lock magnet 127 and lifts the latch 126 out of engagement with the shoulder 125; of

the locking segment 123, thereby indicating to the leverman that the switch has been returned to normal and locked and permitting final movement of the lever 122 again carries the contact arms 117 and. 119 out of engageice 1 ment with their contacts 118 and 120 and 3513' op7ens the circuit through the lock magnet 12 Under certain abnormal conditions the relative positions of the valve mechanism, circuit controller and lever mechanism might be disturbed. For example, it might happen that a repairman depresses piston 28 to open valve 14 manually While making certain adjustments or repairs to the valve mechanism when the lever mechanism F is normal as shown in Fig. 1. In such event, the walking beam 60 would be rocked about its pivot sui'iiciently to open the circuit through the con tacts 7 76 thereby deenergizing the winding 94 of the indication relay K. This Wlll cause the neutral armature 101 to drop and engage its back contact 103, thereby establishing a circuit from battery 131 through Wires'132 and 137, winding of the look magnet L, wires 138 and 152, contact 103, neutral armature 101, wires 153, 147, 140 and 134 back to battery 131. The current in the circuit thus established again energizes the lock magnet L and supplies air pressure to the passageways 36 and 37. By reasonof the fact that the normal valve magnet N is energized when the lever mechanism F occupies its normal position, the valve 48 controlled thereby is open, and consequently pressure will immediately be transmitted to the cylinder 25 and force the piston 28 downwardly. This will rock the walking beam 60 about its pivot in the opposite direction and elevate the piston 28* to its initial positlon, thus permitting the valve li to close. The supply of air under pressure to the cylinder 7 9 will thus be discontinued immediately and before it has had suflicient time to actuate the piston of the fluid pressure motor 0 to reverse the switch.

This return movement of the walking beam 60 again closes contact 7 7 6" and reestablishes the circuit through the indication relay K. The reenergization of this magnet agaln lifts the neutral armature 101 out of engagement with its back contact 103 and breaksthe circuit through the lock magnet L. This permits the valve 39 to close and shut off the supply of air to the cylinder 25 It will thus be seen that the circuit through the back contact 101103 controls the energization'of the lock magnet L under abnormal operating conditions, and that for this purpose the relay K is controlled by the contact device B. Inasmuch as the contact device B is actuated by the valve mechanism, it follows that the position of the valves will at all times occupy their proper relative positions to the pole-changing device E and the lever mechanism F. In this particular my invention eliminates the necessity of what is termed a quick switch for obtaining the desired cooperation between the several elements of the system, thereby not only simplifying the construction and operation of the system but materially increasing the factor of safety. I

Although I have herein shown and described only one form of railway traflic controlling apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention. 1 v

Having thus described my invention, what I claim is:

1. In combination, railway traflic governing means, fluid pres-sure means for operating said trafiic governing means between normal and reverse positions, valve mechanism for controlling the operation of said fluid pressure means and comprising a pair of fluid pressure cylinders, a piston in each of said cylinders, means for selectively controllingtheadinission of fluid pressure to said cylinders, a valve operable by one of said pistons for controlling the operation 01": said traffic governing means toward its normal position,

a valve operable by the other of said pistons for controlling the operation of said traflic governing means toward its reverse position, means operatively connecting said Valves for insuring that one of said valves is closed when the other or" said valves is opened, and a contact device operated by said connecting means.

2. In combination, railway trafic governing means, fluid pressure means for operating said traflic governing means between normal and reverse positions, valve mechanism for controlling the operation of said fluid pres sure means and comprising a pair of fluid pressure cylinders, a piston in each of said cylinders, means for selectively controlling the admission of fluid pressure to said cylinders,a valve operable by one ofsaid pistons for controlling the operation ofsaid traflic governing means toward its normal position, a valve operable by the other of said pistons for controlling the operation of said traflic governing meanstoward its reverse position, means operatively connecting said valves for insuring that one of said valves is closed when the other or" said valves is opened, indication said pistons for controlling the operation of said .traflic. governing means. toward its normal position, a valve operable by the otherof said pistons for controlling'the op-' eration of said tratticgoverning means toward its reverse position, alcvcr operatively connecting said valves for insuring that one'of said valves closed when the other of said valves is open, and a contact device operable by said lever.

4:. In combination, railway traffic governing means, fluid pressure means for operating said traffic governing means between normal and reverse positions, valve mechanism for controlling the operation of said fluid pressure means and comprising a pair of fluid pressure cylinders, a piston in each of said cylinders, means for selectively controlling the admission of fluid pressure to said cylinders, a valve operable by one of said pistons ior controllingthe operation of said traflic governing means toward its normal position, a valve operable by the other of said pistons for controlling the operation of said traffic governing means toward its reverse position, means for indicating the of said indication means, and means operable by said pistons for controlling the'operation of said contact device in accordance with the position of said valves.

5. In combination, railway trai'lic governing means, a fluid pressure device for operating said traiiic governing means between normal and reverse positions, valve mechanism for controlling the operation of said fluid pressure device and comprising a constant pressure chamber, a pair of outlet chambers each communicably connected with said fluid pressure device and with said constant pressure chamber, a fir t valve for controlling communication between said constant pressure chamber and one of said outlet chambers for movement of said traflic governing device toward a normal position, a second valve for controlling communica tion between said constant pressure chamber and the other of said outlet chambers for movement of said traflic governing means toward a reverse position, two fluid pres sure cylinders, a piston in one of said cylinders for operating said first valve, a piston in the other of said cylinders for operating said second valve, a passageway, a control valve for controlling communication be tween said passageway and said constant pressure chamber, control valves for controlling communication between said passageway and said cylinders, means for operating said control valves to selectively actuate said pistons and said first and second valves, means for indicating the position of said tratflc governing means, and a contact device operable by said pistons for controlling the operation of said indicating means in accordance with the positions oi. said first and" second valves relative to that of said traflic governing means.

6. In combination, railway tIEll'lIlC governw ing means, a fluid pressure device for operating said traffic governing means between normal and reverse positions,valve mechaestablishing communication between said constant pressure chamber and one of said outlet chambers to move said traflic governing device toward a normal position, a second valve for establishing communication between said constant pressure chamber and the other of said outlet chambers tomove said traltic governing nieanstoward a reverse position,-two fluid pressure cylinders, a piston in one of said cylinders for operating said first valve,a piston in the other of said cylinders for operating said second valve, a passageway, a control valve for controlling communication between said passageway and said constant pressure chamber, control valves for controlling communication between said passageway and said cylinders, means for operating said. control valves toselectively actuate said pistons and said first and second valves, means for indieating the position of said tratnc governing means, means operatively connecting said first and second valves for insuring that when one is opened the other is closed, and a contact device operable by said connecting means for controlling the operation of said? indicating means in accordance with the positions of said first and second valves relative to that of said trafiic governing means;

' 7. In combination, railway traflic governing means, a fluid pressure device for operat-l ing said traffic governing means between normal and reverse positions, valve mechanism for controlling the operation of said fluid. pressure device and comprising a constant ressure chamber a Jair of outlet chambers 1 P v i 1 5 each communicably connected with said fluid pressure device and with said constant pres-- sure chamber, a first valve for establishing communication between said constant pres- M sure chamber and one of said outlet chambers 1120 let chambers to move said traflic governing means toward a reverse position, two fluid pressure cylinders, a piston in one of said cylinders for operating said first valve, a piston in the other of said cylinders for operating said second valve, a passageway, a control valve for controlling communication between said passageway and said constant pressure chamber, control valves for controlling communication between said passageway and said cylinders, means for operating said control valves to selectively actuate said pistons and said first and second valves, means for indicating the position of said traffic governing means, lever mechanism operatively connecting said pistons for insuring that when one of said first and second valves is open the other is closed, and a contact device operable by said lever mechanism for controlling the operation of said indicating means in accordance with the positions of said first and second valves relative to that of said trafiic governing means.

8. In combination, railway trafiic governing means, a fluid pressure device for operating said trafiic governing means between normal and reverse positions, valve mechanism for controlling the operation of said fluid pressure device and comprising a constant pressure chamber, a pair of outlet chambers each communicably connected with said fluid pressure device and with said constant pressure chamber, a first valve for establishing communication between said constant pressure chamber and one of said outlet chambers to move said trafiic governing device toward a normal pos tion, a second valve for establishing communication between said constant pressure chamber and the other of said outlet chambers to move said trafiic governing means toward a-reverse position, two fluid pressure cylinders, a piston in one of said cylinders for operating said first valve, a piston in the other of said cylinders for operating said second valve, a passageway, a control valve for controlling communication between said passageway and said constant pressure chamber, control valves for controlling communication between said passageway and said cylinders, electromagnetic means for operating said control valves to actuate said pistons and said first and second valves, means for selectively energizing said electromagnetic means, means for indicating the position of said trafiic governing means, a walking beam operatively connecting said first and second valves for insuring that when one is open the other is closed, and a contact device operable by said walking beam for controlling the operation of said indicating means in accordance with the positions of said first and second valves relative to that of said trafiic governing means.

In testimony whereof I afiix my signature.

JOHN P. COLEMAN.

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