US2492374A - Railway switch operating apparatus - Google Patents

Description

Dec, 27, 1949 Filed MarGh 1'7, 1948 6- 11 N f 2 F l 20 20 22 -10 A Kiw U Z5 15 12 1 I6 14 i HW/ 1 JNVENOR.

ATTORNEY Patented Dec. 27 1949 RAILWAY SWITCH OPERATING APPARATUS George W. Baughman, Swissvale, Pa., assignor to The Union Switch & Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application March 17, 1948, Serial No. 15.373

19 Claims. 1

My invention relates to railway switch operating apparatus, and particularly to apparatus for manually operating a spring switch.

In switch operating apparatus of the type described, the switch is connected to a hand-throw lever through a suitable spring biasing means which normally holds the switch in the position selected by the hand-throw lever, but which yields to permit trailing of the switch by a train.

It sometimes becomes necessary for a train which is trailing a switch of this type to stop and back up. This necessitates reversing the switch so that it will not be split by the train. At such times, the switch points may be held in their trailed position by the wheels of a vehicle stopped on the switch. When thishappens, the spring biasing means in the switch mechanism applies a force to the hand-throw lever, tending to move it to its reverse position.

Under such conditions, a switchman operating the hand-throw lever must be careful to apply to the lever a force opposing the spring, in order that he may retain control of the lever and prevent it from moving suddenly to its reverse position. Switch operating mechanisms commonly provide a sufiicient mechanical advantage between the hand-throw lever and the switch so that a switchman may readily retain control of the switch with the spring biasing force acting on it. If the switchman does not retain control of the switch, the resulting sudden movement of the switch may damage the switch operating mechanism or even, conceivably, injure the switchman if he is so careless as to leave some part of his body in the path of the moving lever.

It is desirable to provide means to insure that the switchman will retain control of the switch, and one object of my invention is to provide novel means for this purpose.

Another object is to provide an arrangement for manually operating a spring switch which will give a forcible tactual signal to a switchman of the presence of a load on the hand-throw lever.

A further object is to provide an improved safety latch mechanism for the handrthrow lever of a spring switch.

A further object is to provide improved safety mechanism for use in connection with a manually movable member which is required to be positioned under load.

I accomplish these objects of my invention by providing an auxiliary latch in connection with the conventional latch mechanism commonly used in connection with hand-throw levers for switches. The conventional latch consists of a latch member which holds the lever in its normal position, and a latch releasing pedal arrangement which, upon depression of the pedal, removes the latch member from the path of the hand-throw lever. My auxiliary latch is spaced a short distance from the end position of the hand-throw lever, so that the lever can travel a short distance when the main latch is released. The auxiliary latch is connected to the pedal which releases the main latch so that the auxiliary latch is moved into a position to obstruct movement of the lever whenever the main latch is released. The auxiliary latch is arranged so that the lever will be moved forcibly into engagement with it if there is a spring load on the switch when the main latch is released. This movement of the lever gives the switchman a forcible tactual warning of the load on the lever. The auxiliary latch is provided with a depending tongue which engages the lever and prevents release of the auxiliary latch unless the lever is first backed away from the auxiliary latch far enough to disengage the tongue. Since the lever is under considerable load, this backing away movement of the lever can most readily be accomplished by the operator stepping to the end of the lever and assuming a position where all of his body except his hands'is clear of the path of movement of the lever. The auxiliary lever is self biased to its unlatched position, so that when the pedal is released and the lever is backed away from the auxiliary latch, the latch moves to its released position so that the movement of the hand-throw lever may be completed. The operator has been warned by this time, so that he will not carelessly release the lever for uncontrolled movement. Furthermore, he is in such a position that he may protect himself against the movement of the lever.

Other objects and characteristic features of my invention will become apparent as the description proceeds.

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

In the accompanying drawings, Fig. 1 is a diagrammatic view showing a spring switch and operating mechanism therefor embodying my-ine vention. Fig.2 is a top plan view of a handthrow lever provided with my improved latching mechanism. Fig. 3 is a side elevation of my improved latching mechanism, taken on the line IIIIII of Fig. 2.

Referring to Fig. l, the reference character]v generally indicates a railway switch comprising two fixed rails Zand 3 and two movable rails 4 2 and the movable rail 4 is spaced a short distance from the fixed rail 3. When the switch is reversed,

however, the movable rail l -then engages the fixed I rail 3, and the movable rail 5 is spaced from the fixed rail 2.

The spring connecting rod [I may take any of several well-known forms. Such a spring rod must yieldably hold the switchpoints in which-.-

ever extreme position they are moved. .to by the mechanism 9 with sufiicient force to permit facing point moves over the switch without danger of umpieeeinea or the points. The springrod-must "alsd yi'eld when a train 'trails the switch, and thelifby allow the train to force the switch points -to positions opposite to their initially set -posiftion s; One form of springconnecting rod which will accomplish the necessary results :is shown "andi' described in Letters Patent of the United StatesNo. 1,976,827. granted to Herbert L. Bone onQetober'lG, 193%; for Railway switch operatins ap aratu The; switch operating mechanism 9 may, ;for example, .be'similarrto that shown and described .inliettersl Patent of the United States No. 2,184,-

"870, granted .t o Herbert L. Bone and Kenneth J. JQMc Gowanon Decemberv26, 1939, for Railway switch operatingmechanisms. -It is believed that for thelpurpose s of my present inventionthe following.brief descriptionof this mechanism will be Sllflllllti 'The. switch operating mechanism 9 .includes .-a motion ate [2 which is arranged to bereciprohated-between two extreme positions by means jofa' hand'-throw..lever l3 through .the medium bra -hart I ALand a gear wheel [5 whichncooperates, with. a rack fformed .in. the .motion plate 1.2.

The'moti'ori-plate'i 2 moves in stationary guides] 6.

.A'rollei I'Tis pivotally secured to the underside of the'l motionsplate l2. This roller cooperates witli carnffaces. 18a and 18b formed. on an escapementcran klii. Theicrank l8 rotateson a fixed pivot 'and carrieswith it a switch operating arm .I9 whichjs pivotally attached to the free; end. of the operating rod in. V

*As-thehand-throw lever I3 is rotatedin :a counterclockwise direction from the position shown in Fig.1, the motion plate [2 is -moved to the right. Theinitial movement of plate IZ- carriesthe roller I] tothe rightalong the cam .surface 18a, without causing rotation ofescapement crank I8. When the roller l1 reachesthe 'end of cam portion I8a, it enters the generally semicircular recess .I.8c of the escapement crank i8, and thereafter its continued movement toward the right causes the crank l8 to rotate counterc1ockwis'e..(as viewed in Fig. 1) on its shaft,.thereby-moving the switch operating arm [9 counterclockwise :and shifting theswitch points .from their nor-malto theirreverse positions. After the 'switchhhas reached its reverse position, the roller l-l passes out of the recess I80, and engages the cam surface I 8b, thereby holding the escapement-crank I 8 and theoperating rod-l0 initheir reversepositions. V

The switch operatingmechanism 9 also includes by means of bolts '27.

4 a locking plunger 20 which cooperates with a pair of aligned notches Zla in a lock rod 24 secured to the front rod 6 of the switch. The locking plunger is biased by means of a spring 22 to a locking position in which, when the switch occupies its normal position, it will enter the notches 2 la in the lock rod 2i and thus lock the switch. Locking plunger .20 is arranged to be moved toan unlocking position prior to any move ment of the switch points away from their normal position by the mechanism 9. This may be done by. any suitable means, such as that indicated diagrammatically in the drawings by a lug 52a formed on the motion plate and cooperating with a-lug Zfla on the locking plunger 20. The look-- ing plunger is also arranged to be moved to its unlocking position-prior to any movement of the switch .points away from their normal position by a trailing train, through the medium of a suitable lock releasin linkage connected to the tie rodB-and including a bell crank lever 23, substantially asdescribed in the Bone Patent No. 1,976,- 827, referred to above.

A safety latch mechanismfz l is" providedfor holding the hand-throw lever 13' inits normalposition. This safety latch mechanism is more completely describedj in connectionwith Figs. 2 and 3.

Referring'toF-igs. 2 and 3, it may there be seen that the safety latch mechanism- 24 includes a base casting25 supported on amounting plate 28 The upper part of casting'25 is formed to provide an inner jaw 25a-and a pair of spaced outer jaws 25b-25c. A recess between the inner and outer -jaws receives the hand-throw lever l3. A latch member 28 is'pivotally mounted between the outer jaws '25b-25c on a pin-29. "A latch releasing membertil is also pivotally mounted between the'outer jaws 25b-- 25c-on a pin 3!. The latch member 28 isprovided with a depending mainlatch arm 23oz, a depending-latch operating arm 28b, and an upstanding auxiliary latch arm'28c: The extremity of the upstandingauxiliary latcharm 250 is provided with a depending tongue 28d. The main latch arm 28a'is contoured to engage the inner jaw 2511 so as to prevent further counterclockwise rotationof the latchmember 28 when the parts are in the position shown in Fig.3. The latch member 28 isprovided with an eye 282 to receive the bail of a padlock when the parts are in the position shown in Fig. 3. The bailof the padlock cooperates with a hook 25d formed on the base casting '25 to prevent clockwise motion of the latch member 28 from the position shown in Fig. -3 when the padlock is in place. Thelatch member 28 carries a pin 32 which cooperates with'the hook 25d to limit the clockwise rotation of latch member 28 when the padlock isremoved.

The latch-operating arm 28bcooperates with an upstanding arm 30a of the latch releasing member 30. The extremity of arm 28b is provided with a pedal portion 28f, which is used to force the latch member 28 into a position where the padlock bail may be inserted in the-aperture 28e. V

The latch releasing member'3fi is provided with a pedal 3%, and with-a stop arm 300 which cooperates with a portion 25:; of the base casting 25 to limit rotation of the latch releasing member 30 in a counterclockwise direction.

Operation With the parts. in the. position shown .ein .full

position shown lines in the drawings, let it first be assumed that it is desired to move the switch from its normal to its reverse position with no train in the switch, so that there is no spring load on the hand-throw lever I3. In order to release the hand-throw lever from the latching mechanism, the operator first removes the padlock from the aperture 28c, and then depresses the latch releasing pedal 30b. This turns the latch releasing member 30 counterclockwise. Ihe arm 39a on the member 30 engages the operating arm 28b of the latch member 28 and rotates the latch member. clockwise, thereby carrying the main latch arm 28a out of the path of the lever I3 and moving the auxiliary latch arm 280 to the position shown in dotted lines in the drawings, where'it is in the path of the lever I3. The operator may now lift the hand-throw lever I3 and move it upwardly until it reaches the dotted line position shown in Fig. 3, where it engagesthe auxiliary latch arm 280. In order to move the leverfurther, he must then release the pedal 301), So that the latch 28 will tend to return by gravity to the full line in the drawings. However, such a movement of the latch member 28 is now prevented. by the tongue 2811. This tongue extends over the side of the lever I3 and prevents the latch member 28 from returning to its released position until the lever I3 is backed away from the auxiliary latch 280 a short distance. The operator must therefore back the lever I3 away from latch 280 a short distance, whereupon the latch member 28 will return to the position wherein the auxiliary latch arm 280 is out of the path of movement of lever I3. Movement of the lever I3 to its reverse position may then be completed by the operator. 7 a

Now let it be assumed that the same operation of the hand-throw lever I3 is to be performed, under the conditions existing when a" train is trailing the switch and has stopped with a'truck in the switch so that the switch points'are moved to their reverse positions. Spring II is then compressed and applies a strong biasing force to the operating rod I0, tending to rotate the arm- I9 and the escapement crank I3 counterclockwise as viewed in Fig. 1. When the parts are in their initial position as viewed in Fig. 1, this biasing force acts through the roller I1 and tends to move the motion plate I2 laterally, which movement is prevented by reactive forces on the guides I6. The biasing force therefore initially applies no torque to the shaft I4 or the hand-throw lever I3.

In order to operate the hand-throw lever I3 under these conditions, the operator removes the padlock and depresses the pedal 302) as before. He then starts to lift the hand-throw lever. As soon as he has lifted the hand-throw lever far enough so that the roller I'l passes off the cam portion ISa of the escapement crank I8 and into the recess I8c, then the biasing force acting on the escapement crank I8 becomes effective to bias the roller I1 and motion plate I2 for movement toward the right, thereby applying a counterclockwise torque to the lever I3. As soon as this happens, this biasing force moves the lever l3 forcibly upward into engagement with the latch 280. The latch member 280 is so positioned with respect to the switch operating mechanism 9, that the roller I'I moves into the recess I80 shortly before the lever I3 strikes the auxiliary latch arm 280. This sudden movement of the lever I3 into engagement with the auxiliary latch 280 will be sufiicient to warn even the most careless and negligent operator that the handthe biasing force of the spring I I. The most natural and convenient way for the operator to apply such a large biasing force to the lever I3 is to step around to the end of the lever and bend downwardly over it, placing both hands on the lever and throwing his weight downwardly on his hands. This places the operator in such a position that all of his body except his hands is out of the path of movement of the hand-throw lever. Furthermore, he is in the best position to apply a restraining force to the hand-throw lever I3 throughout the rest of its operating stroke so as to prevent it from moving suddenly.

It should be noted that the position to which the lever I3 must be backed off to release the auxiliary lever 280 is somewhat critical. If the lever I3 is backed away too far, it will engage the main latch arm 28a of the latch member 28, thereby causing the latch member to move clockwise again and restore the auxiliary latch arm 280 to its latching position. The result is that the operator must keep the hand-throw lever I3 under close and careful control at all times during the unlatching phase of its operation. In this way, proper attention on the part of the operator is insured.

Although I have herein shown and described only one form of railway switch operating 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.

Having thus described my invention, what I claim is:

1. Railway switch operating apparatus, comprising a railway switch movable between normal and reverse positions, a manual lever movable between normal and reverse positions, means connecting the lever to the switch including spring means to permit trailing of the switch by a train, a first latch for holding the lever in its normal position, manual means for operating the latch, and an auxiliary latch for limiting the lever move-- ment when the first latch is released to prevent the spring means from sudden-1y moving the lever to its reverse position when the first latch is 0p erated while a trailing train is in the switch.

2., Railway switch operating apparatus as in claim 1, in which the auxiliary latch limits the lever to a small initial movement, and in which initial movement of the lever by the spring means gives toan operator a tactual signal of the pres ence of a biasing force on the lever.

3. Railway switch operating apparatus as in claim 1, in which the means for connecting the lever to the switch includes a lost-motion connection which provides a range of movement of the lever at the beginning of its travel from its normal position wherein the lever moves independ ently of the switch and is not subjected to any biasing force of the spring means, and in which the auxiliary latch becomes efiective just after the lever has passed through the said range of lever movement and is subject to the biasing force of the spring means. T

4. Railway switch operating. :apparatus l-as I'll-'1 claim- Linoluding meansrconnecting the auxiliary latch totthe firstclatch operating meansifor iconcurrent movement therewith so thatthe auxiliary latch is v moved to its latching position. concurrently with: the release of the'first' latch,

5. Railway.switchoperating apparatus as in claimn4, in which the auxiliary ilatch permits movement of the .lever'to an intermediateisposition out of the pathlof the firstalatch sol that movement of, the latch operating? :means to its latching position after the lever. reachesasaid intermediate position releases the: lever. .from both .latches.

6. Railwaysxvitch ;,opcrating apparatus as in claim 11, in which the. auxiliary latchhas a .tongue which engages :the lever r-andprevents release .of the auxiliary latch. except by. a-movement 'of i the lever toward itsnormal position.

'7. The combinationewith'a railway-.switchmovable between normal and reversed positions, .a manual lever movablezbetween normal and; reversed positions, meanseonnecting the lever to the switchincluding spring means to permittrailing .of the switchbyia train, latch means for holdring the lever. in its'normal position and manual means for releasing the latch means, of :an auxiliarylatch for limiting the lever-movement when the latch means is released so that-operationof thelever by the spring means duringssuch limited movement gives to an operatoraitactual. signal of the presence of abiasingforce onthelever.

8. The combinationzwith. a railwayswitchmovable between normalhand reversed positions," a

manual lever movable between normal and-reversed positions, means connecting the lever: to the switch including springmeans to permit trailing of the -switch-i by a train and. lost-.motion means .to provide a range oflever movement at the iceginning of its stroke from normal to-re versed position wherein the #lever moveswindependently of the switch and isno-t subjectedto any biasing force vof the spring means latch means for holding the lever in its normal position and manual means for releasing the latch means,

of an auxiliary-latch efiectivepwhen-the latch means is released-to limit-the lever-movement to a point just beyond-saidrange so-that the spring means. is effective when the lever is-oper- .ated while a trailing tr-ain is-inthe switch to move the leverashort distance beforeit strikes the auxiliary latch, thereby givingto the operator a tactual signal of the presence of -a-biasing force on the lever. I V

9. Manualoperating apparatus, comprising a a devicesubject-at timesto a-biasing force, a manuallymovable member, a connection-between the member and the device, latch'means'for holding the memberin a selected position, manual means I for operating the latch means, and an auxiliary latch for limiting the movement of the member when the latch means is released so that a biasing force on the device will givela ltactualnsignal, of

its presence to the operator; by moving the mem ber until it strikes the auxiliary :latch.

10. Manual .operating apparatusiflas in claim 9, includingimeans connecting the auxiliary latch to the latchoperating means -for concurrent movement therewith so that the auxiliary latch is released and moves to itsunlatchedg position as the latch means. movesto its latching position.

Ma ua o ting 1 e paratus ..as incl-aim 9, uding aton ueionitheiauxil arylatch which engages the movable membenmnd; pnevcntsare, ,7

Eleaseenfuthe auxiliary; latchunless the movable memberris first, backed away..

112. Manua1 .,operating apparatus in :claim 11, in whichlthe .auxiliaryhlatch gisabiased to its released position so that when'the manual latch operatingcfmeanss is released and, the movable memberis. backed away from theauxiliary latch .the latter-returns .to its released position.

13. Manual operating apparatus comprising a manually movablemember, latch means for bolding ithe member in a selected position, ,manua1 'means ,ior operating; the latch .means andman auxiliary latch for .limitlngthe: movement of the :memberwhen the latch means is released so that if the member-is loaded atactualsignalof the presence of the loadwill be givento'the woperatoruby the initial. movement of the memberinto engagement with the auxiliary latch.

, 14. Manual operating apparatus as. in, claim l3, including! means -.connecting: the i-auxiliary latch, tothe ilatch operating means ,ior concur- ;rent movement therewith so that ithe iauxiliary latch movesto itslatchingposition asl-thellatch means -,is released and, moves to its unlatched position-as the latch means moves toitslatching position, and ,a tongueon the auxiliary latch which engages the movable membenandprevents releaselofythe auxiliary latch unless; the movable member is first backed away; in which the aux- .iliarylatchis biased to; its re1easedposition so that when the manual latch operating means is released and the movable-member is backed away :from the auxiliary, latch ,the latter; returns to its released position; andin which the auxiliary latchisspacedfrom the latch means sufficiently so that the member may he backed away ,far enough to release the auxiliary latch without moving into, a position where it. will he: engaged bythe latch -means.

, 15. Railway switch operating apparatus,comp isins arailway sw ch movab ez ee n rma and reversepositions, a hand-throw leverr movablejbetween normal and reversepositions, means connecting the lever -to the switch,,.including spring-meansto permit trailing of the switch by a trlain,l latch means for the hand-throw lever including a support for the lever in its normal position-,firstandsecond jaw means .on-the sup- ,port;forming betweenthem an aperture-for receiving the lever, said first Jawmeans comprising .a pair of spaced jaws, first and second pivot pins ca rried by the spaced jawsand-extending between them, a latch member rotatable. on; said first'wpin and having first and second latch arms -and ,an operating arm, and a latch-operatin member, rotatable on the second pin andhaving azfirst pedal arm and a second arm for engaging the operating'arm of thelatch member'to rotate said member, saidlatch member ,beingbiased by e gravity to a normal positionin which saidifirst tio r'whelein the first latch arm is removed ,from

between ,the jaw means and the second latch arm lies inthe path of thelever tolimit its movement toward said second position,

16. Railway switch operating apparatus, comprising-arailway switch movable between normal and reveiyse positions, a hand-throw lever movablebetween.normaland reverse positions, means connecting the lever to the 1 switch including sprin :means to, permit trailing ;or the switch bylatram, latch means ior ,thevhandsthrowi-lever including a support for the lever in its normal position, first and second jaw means on the support forming between them an aperture for receiving the lever, said first jaw means comprising a pair of spaced jaws, first and second pivot pins carried by the spaced jaws and extending between them, a latch member rotatable on said first pin and having first and second latch arms and an operating arm, and a latch operating member rotatable on the second pin and having a first pedal arm and a second arm for engaging the operating arm of the latch member to rotate said member, said latch member being biased by, gravity to a normal position in which said first latch arm lies between said jaw means and prevents movement of the lever from its normal position, said latch member also being movable by operation of said pedal arm to a second position wherein the first latch arm is removed from between the jaw means and the second latch arm lies in the path of the lever to limit its movement toward said second position, said second latch arm having a tongue which engages the lever and prevents removal of the second latch arm from the path of the lever unless the lever is first moved back toward its normal position far enough to clear said tongue.

17. A lever latch stand for use in connection with a lever movable to and from a normal position, comprising a first latch biased to a latching opposition to its bias.

18. A lever latch stand for use in connection with a lever movable to and from a normal position and at times subject to a load tending to move the lever away from said normal position, said latch stand comprising a first latch biased to a latching position wherein it holds the lever in its normal position and movable therefrom to a released position wherein it permits movement of the lever away from its normal position, an auxiliary latch connected to the first latch for concurrent movement therewith and effective when said first latch is in its released position to obstruct the path of movement of the lever a predetermined distance away from its normal position, said auxiliary latch being moved out of the path of the lever concurrently with movement of the first latch to its latching position, and manually operable means for moving said first latch to its released position in opposition to its bias so that the lever may be moved through said predetermined distance into engagement with said auxiliary latch, said auxiliary latch being releasable by disengagement of the lever therefrom with concurrent release of said manually movable means.

19. A lever latch stand for use in connection with a lever movable to and from a normal position and at times subject to a load tending to move the lever away from said normal position, said latch stand comprising a support for the lever in its normal position, first and second jaw means on the support forming between them an aperture for receiving the lever, said first jaw means comprising a pair of spaced jaws, first and second pivot pins carried by the spaced jaws and extending between them, a latch member rotatable on said first pin and having first and second latch arms and an operating arm, and a latch operating member rotatable on the second pin and having a first pedal arm and a second arm for engaging the operating arm of the latch member to rotate said member, said latch member being biased by gravity to a normal position in which said, first latch arm lies between said jaw means and prevents movement of the lever from its normal position, said latch member also being movable by operation of said pedal arm to a second position wherein the first latch arm is removed from between the jaw means and the second latch arm lies in the path of the lever to limit its movement toward said second position.

GEORGE W. BAUGHMAN.

No references cited.

Certificate of Correction Patent No. 2,492,374 December 27, 1949 GEORGE W. BAUGHMAN It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 7, line 70, after the word latch insert moves to its latching position as the latch means; and that the said Letters Patent should be read with this correction therein that the some may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 25th day of April, A. D. 1950.

THOMAS F. MURPHY,

Assistant Commissioner of Patents.

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