US2320779A - Safety locking device - Google Patents

Description

June 1, 1943. A. F. HUBER 2,320,779

SAFETY LOCKING DEVICE Filed May 23, 1940 2 SheetS-S heet 1 ATTORNEY June 1, 1943. F, HUBER 2,320,779

SAFETY Locxmg DEVICE Filed May 23, 1940 6 w I FEJ .2 Sheets-Sheet 2 BY IN$NTER ATTo'RNEY Patented June 1, 1943 SAFETY LOCKING DEVICE Albert F. Huber, Chicago, Ill., assignor to The American Brake Shoe and Foundry Company, New York, N. Y., a corporation of Delaware Application May 23, 1940, Serial No. 336,701

9 Claims.

The invention relates to railway track equipment and, more particularly, to safety locking devices for locking a switch in closed position.

The safety locking device, according to the invention, may be used with any conventional switch stand or other switch operating devices, although it is more particularly adapted for use with a switch stand of the ground-throw type. The safety switch locking device in its preferred form comprises a flat plate adapted to rest upon, and to be secured to, the top of a railway tie. Depending from the plate is a stirrup adapted toslidably receive the locking rod which extends independently of the switch stand to the switch. The stirrup has an open central chamber depending from which is a housing in which is slidably mounted a locking lug for engaging a notch in the underside of the lock rod. The lug has a portion projecting outwardly through a slot in the housing to support a treadle for engagement by the foot of the switchman. A suitable spring device urges the lug upwardly and a suitable padlock arrangement may be provided to lock the locking device.

The locking lug may be provided with an upwardly extending finger or tongue which, in the event the safety locking device is used with a ground-throw switch stand, engages a latch lever used for locking the operating lever of the switch v stand. The latch lever may be so constructed that the raising of the operating lever to operate the switch depresses the treadle member to unlock the locking device.

The central chamber may be provided with a removable cover having an opening through which a part of the latch lever extends. In the event the locking device is used with switch stands other than the ground-throw type or where the switch stand latch is omitted, the cover for the locking device may not have the notch, in which case the locking device can only be operated by depressing the treadle by the foot.

The invention also consists in certain new and original features of construction and combination of parts hereinafter set forth and claimed.

Although the novel features which are believed to be characteristic of this invention will be particularly pointed out in the claims appended hereto, the invention itself, as to its objects and advantages, and the manner in which it may be carried out, may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part thereof, in which Ill and the switch point by I I.

Fig. 1 represents a-layout of the safety locking device used with a ground-throw switch stand connected up to a conventional switch;

- Fig. 2 is a plan view of the safety locking device and the part of the switch stand cooperating therewith;

Fig. 3 is a section on the line 3-3 of Fig. 2;

Fig. 4 is a section on the line 4-4 of Fig. 2;

Fig. 5 is a section on-the line 5--5 of Fig. 2;

Fig. 6' is a section on the line 66 of Fig. 3; and

Fig. 7 is a fragmentary view corresponding to Fig. 5, showing a modified form of latch lever.

In the following description and in the claims, various details will be identified by specific names for convenience, but they are intended to be as generic in their application as the art will permit.

Like reference characters denote like parts in the several figures of the drawings.

In the drawings accompanying and forming part of this specification, certain specific disclosure of the'invention is made for purposes of explanation, but it will be understood that the details may be modified in various respects without departure from the broad aspect of the invention.

Referring now to the drawings and more particularly to Fig. 1, one side of a conventional switch is shown, the stock rail being indicated by These'rails rest upon suitable tie plates, which'in turn rest upon suitable ties, certain of which, IZ'and l3, are somewhat longer to support the switch stand l5 and the safety locking device 25. The switch is provided with conventional switch rods indicated by M extending to theother switchpoint (not shown) as will be understood by those skilled in the art. The connecting rod l6 connects one of the switch rods I4 with the switch stand l5 and the locking rod 24 connects the switch point H with the safety locking device 25.

The switch stand I5 is of the ground-throw type comprising a base I1 suitably spiked to the ties l2 and I3 and having an operating shaft 20 supporting an operating lever l8 with the usual weighted handle IS. The switch stand shown for purposes of illustration is of the type described and claimed in Hoffman & Perdue Patent .No. 2,054,543, dated September 15, 1936, to which reference is made for a more complete disclosure of the switch stand.

In order to operate the switch stand, when thus interlocked with the safety locking device,

a certain amount of lost motion'is necessary, this lost motion being present in all ground-throw switch stands. In the switch stand shown in the above-mentioned patent, a special lost motion arrangement is provided for the operation of the switch stand itself, and this lost motion may be conveniently utilized in the present invention.

The switch stand I5 has a latch 26 spiked to tie I3. The latch, asshown, is made of a metal strap suitably bent to form the base 2! and an upright post 28 having a vertical recess in which is pivoted the latch lever 3|. The post 28 is provided with a notch or recess 29 having a flaring mouth to receive the operating lever IS. The latch lever 33! has an upper finger 32 adapted to overlie the operating lever I8, a lower finger 33 to engage the locking device 25, and is pivoted to the post 28 by a pivot bolt 34.

The locking device 25 comprises a base 37 suitably spiked to the tie or otherwise secured as by screws 36. Depending from the base 3'! is a stirrup 38 in which is slidably mounted the lock rod 24. Stirrup 38 has a central chamber 39, depending from which is a housing having a reduced lower'end 4| providedwith a drain-hole 42.

Slidably received in the housing 40 is a treadle lock comprising a lug 43 adapted to seat in the notch 44 in the lower side of lock rod 24. The lug 43 projects outwardly through a slot in the side of housing 40'to a treadleor pedal member 45. Lug

43 has a stem 46 slidable in reduced portion 4|. Surrounding stem 46 is a helical spring 41 resting upon shoulder 48 and abutting the underside of lug 43. An apron 49 depends from treadle to cover the slot in housing 43 and to prevent ingress of water, dirt orother foreign matter.

'Treadle 45 is provided with a perforated eye 50 adapted to receive the bow'of a padlock 53 which abuts the top edge of flange 5I which, along with flange 52, projects outwardly from the housing 40 on opposite sides of apron 49.

Lug 43 has an extension or tongue 54 passing up in back of lock rod 24 and having a concave nose in; which rests finger 33 of latch lever 3I. Cover 55; has a notch 56, in its top wall to pass finger 33 andhas bolts -51ipassing through its side wall to hold the cover in position on stirrup 38. The side wall of cover 55 also has a notch to clear eye 50. 1.

Insome cases, instead of shaping the finger '32, as shown more particularly in Figs. 5 and 6, in the form of a rounded nose engaging the vupper edge of operating lever 24, i1; is preferable to use the cam surface, indicatedby I32 in Fig. '7. The construction of the modified form shownin Fig. 7 is otherwise the same as in the otherfigures. The cam surface I32 assists in providing the proper mechanical advantage for depressing the treadle lug 43 by lifting operating lever I8, without requiring the operator to depresstreadle 45. e

Although it is thought that the operation of the safety locking device will be apparent to those skilled in the art from the above description, it is briefly set forth below. It will be understood that the position of the switch shown in Fig. l is the main line position and both the switch stand I5 and-the safety locking device 25 serve to lock the switch in this position. So long asthe padlock 53 is in the position with its .bow passing through the eye 50, it is impossible to depress the treadle 45 and it is impossible to lift the operating lever I8. Any attempt to' lift lever I8 will serve only to depress the finger 33 against the extension 54 which is prevented from moving downwardly by the padlock 5B.

When it is desired to throw the switch to permit passage of a train on the branch line, the padlock 53 is removed. The operator may operate both the switch stand I5 and the safety looking device 25 merely by raising operating lever I8 and without stepping upon treadle 45. The raising of operating lever I8 moves finger 32 upwardly, swinging latch 3I about pivot 34 so that finger 33'presses extension 54 downwardly, disengaging lug 43 from notch 44 in the underside of lock rod 24. In any ground-throw switch stand, there is sufficient lost motion to permit the necessary upward movement of operating lever I8 to disengage lug 43 from notch 44 before moving the switch point II and lock rod 24. As pointed out above, the particular type of switch stand shown for purposes of illustration and described and claimed in Patent No. 2,054,543 is particularly adapted for use with this safety looking device because of the special lost motion arrangement incorporated in the switch stand.

To complete the throw of the switch to open position, the operating lever I8 is raised completely and-thrown over to engage the left-hand rest 35 in Fig. 1. This moves the point II away from the stock rail Illto permit passage of the train on the branch line, as will be understood by those skilled in the art. The operator may, of course, step on pedal 45, when lifting lever I8, if he so desires.

To return the switch to main line or closed position, the operating 'lever I8 is lifted and thrown over to engage'the latch 26 in Fig. 1, the treadle 45 being held in depressed position by the engagement of lug 43 with the bottomof lock rod 24. The latch 3| is also in lower position with the upper finger 32 uncoveringslot 29 so that theoperating lever I8 maybe swung home to the bottom of notch 29. As soon as the switch point II engages the stock rail ID, the treadle lug 43 engages notch 44 which raises latch 3| to swing finger-32 over the top of lever IS. The bow of padlock 53 is then threaded through eye '50 to lock both safety locking device and switch stand in closed position.

It will be understood thatthe' safety locking device 25 may also be used with other switch Jo eratingdeVices, including switch stands other than the ground-throw type, in which event the latch 26 is not used. Inthis event the extension 554 performs no function and the cover 55 may be replaced by a similar coverbut without the notch In some instances, the tongue 54 may be of sufficient. length to comev flush with the upper surface ofcover55 and top plate 31, and the top surface of tongue 54 may be flat instead of having a concave, nose. Thefinger 33 will, of course, be correspondingly shortened. With such a constructioIbthe same notched cover 55 may be used whetherja ground-throw switch stand is used or not since the flush tongue 54 acts to keep dirt and other foreign substances out of the locking device. I

Thus a safety locking device is described which is ru gged in construction and simple in operation. The, entire locking device, exclusive of cover 55, may be made of malleableiron and the cover 55 may be made of cast iron. One padlock locks both the'hand lever and the safety locking device and all vulnerable parts of the safetylockof the ties and between the ties where they are inv protected position and where they cannot be easily engaged by foreign objects dragged by a train. It is possible for foreign objects to entirely dislodge the switch stand I5 and carry away the latch 26 Without affecting the locln'ng device 25 since all parts are separately fastened to the ties. The padlock cannot be inserted through the looking eye 50 unless the treadle lug 43 engages the lock rod notch 44 and the switch therefore closed. The straight vertical foot action of the treadle does not tend to unbalance theoperator as do conventional devices where the pedal is fulcrumed. lhe parts of the locking device are so designed that they may be easily molded and assembled.

While certain novel features of the invention have been disclosed and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes may be made by those skilled in the art without departing from the spirit of the invention.

What is claimed is:

1. A switch point lock having a top plate adapted to rest upon and to be secured to the top of a railroad tie or the like, said plate having a stirrup depending therefrom, a lock rod for connection to the switch and having a notch in the underside thereof, said stirrup having a lock rod recess to slidably receive said lock rod and a centr-al chamber, said stirrup having a housing depending from said central chamber, a treadle lock comprising a lug adapted to seat in said notch, said lug having a depending shank, a helical spring surrounding said shank and acting be- I to connect with a switch, a ground-throw lever having connection with said mechanism, a lever latch on one of said ties to receive said lever when the switch is in main line position, said latch comprising a support secured to the tie and having an upwardly opening slot to receive the ground-throw lever, a lever catch, a pivot connecting said catch with said support, said catch having a first part engaging over the top of said ground-throw lever and a second part, a locking device comprising a plate secured to the tie having a depending stirrup, a lock rod having a notch in the underside thereof and extending to said switch, a housing projecting from said stirrup, a treadle lock having a locking lug slidable in said housing and engageable with said notch and having a treadle projecting outwardly through the side of said housing, said lug having an upwardly extending tongue engageable with said second part, said pivot and said first and second parts of said lever catch being so related that said locking device may be opened either by raising said ground-throw lever to throw the switch or by stepping on said treadle.

3. In a railroad switch construction, a groundthrow switch stand comprising a body having operating mechanism adapted to be connected to a switch, said operating mechanism having a low, horizontal, operating shaft located between adjacent railroad ties, a ground-ithrow lever on said shaft, and having a lost motion connectionwith said mechanism, a lever latch on one of said ties adapted to receive said lever for holding the switch in main line position, said latch comprising a housing member secured to the tie and having an upwardly, opening first slot to receive the ground-throw lever, and a second slot intersecting said first slot, a lever catch located in said second slot and having a top finger engaging the top of said ground-throw lever and a depending finger, a pivot connecting said catch and said housing member, a locking device comprising a top plate spiked to the top of the tie having a depending stirrup, a lock rod having a notch in the underside thereof and extending to said switch, a housing projecting from said stirrup, a treadle lock having a locking lug slidable in said housing and engageable with said notch and having a treadle projecting outwardly through the side of said housing, said lug having an upwardly extending tongue engageable with said depending finger through an opening in the top of said housing, said pivot and said first and second parts of said lever catch being so related that said locking device may be opened either by raising said ground-throw lever to throw the switch or by stepping on said treadle.

4. A' switch point lock having a top plate adapted to rest upon and to be secured to the top of a railroad tie or the like, said plate having a stirrup depending therefrom, a lock rod having a notch in the underside thereof, said stirrup having a lock rod recess to slidably receive the lock rod and a central chamber, said stirrup having a housing depending from said central chamber, a treadle lock comprising a lug adapted to seat in said notch, said lug having a depending shank, a helical spring surrounding said shank and acting between said lug and the bottom of said housing, a treadle secured to and projecting outwardly from said lug, said housing having a vertical slot to permit vertical sliding movement of said treadle, said treadle having an apron depending from the underside thereof to cover said slot, said treadle having a padlock eye adapted to receive the shackle of a padlock, said stirrup having a part projecting outwardly alongside said apron against the top of which said shackle abuts to prevent opening of the locking device, the back wall of said stirrup having a recess to receive an extension tongue secured to said lug.

5. A switch point lock comprising a top plate adapted to rest upon, and to be secured to, the top of a railroad tie, said plate having depending therefrom a stirrup located against the side of the tie, a lock rod having a notch in the underside thereof, said stirrup having a lock rod recess to slidably receive said lock rod and a central chamber, said stirrup having a housing depending from said central chamber, a treadle lock comprising a lug adapted to seat in said notch, said lug having a depending shank, a helical spring surrounding said shank and acting between said lug and the bottom of said housing, a treadle secured to and projecting outwardly from said lug, said housing having a vertical slot to permit vertical sliding movement of said treadle, said treadle having an apron depending from the underside thereof to cover said slot, said treadle having a padlock eye adapted to receive the shackle of a padlock, said stirrup having parts projecting outwardly on opposite sides of said apron against the top of one of which said shackle abuts to prevent opening of the locking device, the back wall of said stirrup having a recess behind said lock rod to receiv an extension tongue secured to said lug, a curved cover member for said central chamber having a notch to clear said tongue and having a second notch to clear said eye, and bolts passing through the vertical wall of said cover member into the outer wall of said stirrup.

6. A switch point lock having a top plate adapted to rest upon, and to be secured to, the top of a railroad tie or the like, said plate having a stirrup depending therefrom, a lock rod for connection to the switch and having a notch in the underside thereof, said stirrup having a lock rod recess to slidably receive said lock rod and a centralchamber, said stirrup having a housing depending-from said central chamber, a treadle lock comprising a lug adapted-to seat in said notch, said lug having a depending shank, a helical spring surrounding said shank and acting between said lug and the bottom of said housing, a treadle secured to and projecting outwardly from said lug, said housing having a slot to permit sliding movement of said treadle.

7.'A switch point lock having a top plate adapted to rest upon, and to be secured to, the top of a railroad tie or the like, said plate having a stirrup depending therefrom, a lock rod for connection to the switch and having a notch in the underside thereof, said stirrup having a lock rod recess to slidably receive said lock rod, said stirrup having a vertical guideway, a treadle lock slidably mounted in said guideway and comprising a lug adapted to seat in said notch, a helical spring under said lug acting between said lug and said stirrup, and a treadle rigidly secured to and projecting laterally from said lug and located below the top of the tie.

8. A switch point lock comprising a housing for securement to arailroad tie or the like, a lock rod having a notch in its under side and adapted for connection to a switch, said housing having a lock rod recess to slidably receive said lock rod, a treadle lock comprising 2. lug adapted to seat in said notch, a treadle rigidly secured to said lug and projecting laterally therefrom, said housing having a vertical straight line guideway for said treadle lock and a slot through which said treadle projects to permit vertical straight line sliding movement of said treadle, and a spring acting between the under side of said treadle lock and said housing to urge said lug into engagement with said notch.

9. In a railroad switch construction, a switch stand comprising a body having operating mechanism to connect with a switch, an operating lever having connection with said mechanism, a lever latch to receive said lever when the switch is in main line position, said latch comprising a support having a slot to receive said lever, a lever catch pivoted to said support and having a first part engaging said lever, a locking device comprising a housing having a recess, a lock rod having a notch and slidable in said recess and extending to said switch, a treadle lock having a locking lug slidable in said housing and engageable with said notch and having a treadle projecting through the side of said housing, said lever catch also having a second part which has simple contact engagement with said treadle lock, said lever catch and said support being so arranged that the raising of said lever to throw the switch swings said lever catch to disengage said lug from said notch, said lug being disengageable from said notch also by stepping upon said treadle, said switch stand and lever latch being readily and completely disengageable from said locking device in case said switch stand and lever latch are carried away by accident.

ALBERT F. HUBER.

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