US1598485A - Switch-interlocking device - Google Patents

Description

Aug. 31 1926. K 1,598,485

J. T. MCGARRY l SWITCH INTERLOGKING lDEVICE Filed Oct. 19 1925 3 Sheets- Sheet l FL' f1 :fw/ j v f6 wimf Attorney.

Aug. 31 1926.

. 1,598,485 F J. T. MCGARRY SWITCH INTERLOCKING DEVICE Filed OCt. l9 1925 I5 Sheets-Sheet 2 4 v l .Y Qn/inzio? ,6.9 Z0' Z5 Attowney.

Aug. 3l 1926..

J. T. MCGARRY SWITCH INTERLOCKING DEVICE Filed Oct, 19 1925 5 Shouts-Sheet 5 Y 'Innen/0r n wf dit or/ey;

Patented Aug. 31, 1926.

UNITED SI'AKI'E;,Si

JOHN T. MCGARRY, OF CNCNNATI, Ol-IIO.V

SWITCH-INTERLOCKING DEVICE.

Application filed October ,19, 1925. Serial No. 63,403.

My invention relates ,to switches and switch-stands and interlocking devices thereiior, 4wherein there is provision for insuring that `the point `rail of the switch has been'drawnl safely close to the stock rail, throughthe medium of a retentively engaging means or plunger coacting with an interlocking bar connectedr to the point rail.

An object of my invention is to reduce as 'tar as possible the chance ,Ot the interlocking vmechanism being disrupted by any object dragged or thrown alongside the switch, such as an object projectingfrom a passing train, or such as some object struck by a train, as a vehicle, beingthrown thereby alongside the switch. A further object is ,to provide for padlockingfthe interlocking device in such a umanner that the lock will zbe fully protected in such accidents as jnst instanced, so that the switch not only is held closed, against the effects oi' vibration `et the passing trains, attersuch an accident resulting Lin destruction of the switchstand, but also isfkept safely locked, pending repair ofthe switch-stand; and in tact using the device as means vfor locking the switch against tampering and the like, :instead of the padlock as usually applied, directly .to the switch-.stand and subject to .being carried away with the stand in such accidents. A -lfurther object is to make the operating mechanism ofthe device as simple and reliable as possible, guarding also against the device becoming vinoperative from wear or loosening ot any part ot the mechanism, or 'from clogging by dirt or ice. A further object is to minimize the obstruction otlfered by the device, vwhen installed alongside the switch-stand, to the switchman aproaching the' stand tooperate it, and to make the device itself' most convenient for the switchman to operate for disengaging the interlocking means preparatory to throwing the switch. @ther objects will appear in the course of the ensuingr description.

1 attain these objects by the device illustrated, .for example, in the accompanying drawings, in which- Figure 1 is a general perspective view oil part oli a 4switch and a switch-stand connected thereto and -having/ my improved interlocking device applied thereto;

Fig 2 isa rear end elevation et Vthe device and part of Ithe head ,block in which it is mounted, part only of the interlocking bar being shown, and the casing therefor being omitted;

Fig, 3 is a vertical. cross-section ot the interlocking bar and its casing and part of the yhead block, to which the latter is attached; i y

Fig. 4L is a similar view showin g the interlocking bar and its casing as used in the modification of my invention illustrated ,in Figs. 7, 8 and 9;

Fig. 5 is a plan view correspondingto F ig. 2, part of the base of the switch-stand beingshown.

' Fig. `6 is a vertical longitudinal section on the plane of the line 6 6 oFig. 5;

Fig. rTis a plan view similar to' F 5, showing the modification o :t my invention;

Fig. 8 is a sectional view, similar to Fig. 6, further illustrating the modification; and

Fig. 9 is a partial rear end elevation di this modification.

As exemplilied in Figs. 1 to 6, inclusive, the interlockingbar 1 has the roundthreaded endlQ extending through the bent-down end ofvaplate 3 which, as is known inthe art, is liXed to the end of the point rail i oit the switch; and nuts 5 and 6 are screwed onto this end part 2 againstopp'osite sides of Athe plate 3, so that this bar 1 :is very intimately connected to the thin end part et thepoint rail l1. `will be understood that my ,iinproved device maybe used in conjunction with any .type'of switch-stand desired; the stand shown `herein (Fig. l) beingthat well known ,kind with a high frame 7 in which a shaftS is journaled vertically, carrying on its lower end kthe crank 9 which isconnected tofthe two point rails l and 1() by the rods 11 and-12 inthe usnaljman'ner. At `the top of the frame 7 a hand lever 13, .tilted on ythe shaft 8, swings around a segment .l-i ninety degrees to throw theswitch, and is jointed so ,that its `outer end partmay drop into eitheroneoif two notches 15 and .16`inthe segment, where may `b e locked against withdrawal by inserting a vpadlock in `an earl? Aat the joint of `the lever. This padlock is .not shown; as I yprefer to lock the switch by means of a padlock applied .directly 'to the interlocking device, as .will be described.

The interlocking ybar ALentends alongside the adjacent .head block 118 -O the Switch,

seine distance below the top thereof, being, for most of its length, of rectangular crosssection, and, in this example, having its broader sides horizontal. The interlocking housing 19` in the present example, comprises a top 2O fastened down on the top of the head block 18 just beyond the switch-stand from the track, by means of four screws 21, and extending across and partly coveringy a gain 22 cut entirely across the head-block 18 and somewhat less than half way down therethrough. This housing also comprises the stirrup 23 having the transverse rectangular opening 24 through which the outer end part of the interlocking bar 1 slides in its movement with the switch rail 4; this stirrup 23 having wing portions 25 through which, preferably, two additional screws 26 are passed below the bar 1 into the side of the head block 18. Above the stirrup 23 and forming its junction with the top 20, is the head 27, in which is a cavity 28 registering with the adjacent end of the gain 22; and a bore 29 extends up through the bottom of the stirrup, with an alined continuation 30 in the top of the stirrup, into the cavity 28, so that the plunger 31, with its top eye 32 in the cavity 28, may slide up and down in these bores 29 and 30, across the interlocking bar opening 24. The interlocking bar 1 has the opening 33 down through it, so located that, when the bar 1 is properly adjusted by means of the nuts 5 and 6 at the point rail, this bar opening 33 will register with the bores 29 and 30 of the stirrup, and the plunger 31 can pass down through. the bar 1, if the point rail 4 is drawn snugly to the stock rail 34, in its correct safe relation thereto, but not otherwise.

Preferably, the eye 32 of the plunger 31 is wider than the bore 30, so that the plunger 31 cannot drop down therethrough, even though it were detached from its operating mechanism. This operating mechanism comprises the lever 35 having a fork 36 straddling the plunger eye 32, with a pin 37 transversely through the fork members and the eye; and preferably the sides of the cavity 28 are close enough to prevent escape of this pin 37 endwise. Intermediate of its ends the lever 35 has a hub 38 with a transverse bore; and the top 2O of the housing 19 has a wall depending int-o the gain 22 of the head block, this wall comprising side parts 39 with transverse bores, receiving the lever hub 38 between them and having the fulcrum pin 40 passed through the alined bores and firmly fastened at its ends at the outer sides of the wall parts 39. Preferably, the wall also comprises a lower part 41 adjoining the side parts 39 below the hub 38 and fitting rather closely to the bottom of the head block gain 22, as do the side parts 39 to the sides of the gain; so that this wall, with the lever hub 38 in it, makes up a substantial closure of the part of the gain 22 next to the head cavity 28, in which the forward arm of the lever 35 swings up and down.

lThe opposite arm of the lever 35 swings up between two ledges 42 formed by curving the housing top 20 downward over the edges of the gain 22 and then inward partly thereacross, from the fulcrum wall to the end of the top, these ledges also joining said wall above the hub opening thereof. On the top of this outer arm of the lever 35 is the locking ear 43, the transverse opening 44 of which is above the ledges 42 when the plunger 31 is down in the interlocking bar 1; so that if the bow of a padlock 45 (Fig. 1) is passed through the opening 44 it prevents depression of this outer end of the lever 35, and raising of the plunger 31, by engagement with the side ledges 42 of the housing. Preferably, ribs 46 extend from the respective ledges 42 down and forward to the wall side portions 39, and other ribs 47 extend from these wall portions 39 forward to the respective sides of the head 27; all these ribs 46 and 47 fitting rather snugly to the sides of the gain 22. Thus the ribs reinforce the connection of the top 2O and head 27, and by engagement with the sides of the gain reinforce the fixing of the housing 19 to the head block 18 by the screws 21 and 26. On the rear end of the lever 35, as here illustrated, is formed the treadle 48, within the end part of the gain 22 and swinging close to the rear ends of the ledges 42. lVhen the treadle end of the lever is depressed, raising the plunger 31 out of the interlocking bar 1, so that the switch may be thrown, the ear opening 44 is below the ledges 42, which, together with the treadle 48 immediately to the rear of, and now slightly below, the ledges 42, prevents insertion of the padlock 45. Thus it is impossible to padlook the device unless the plunger 31 is engaged fully through the interlocking` bar; and it has been seen that this engagement cannot occur unless the point rail 3 is in safe relation to the stock rail 34.

To afford ample space for insertion of the switchmans foot to the treadle 48, the gain 22 is widened from its front end adjoining the head cavity 28, to its rear end contain ing the treadle; this widening being increased in its upper region, to the rear of the housing top 20, by beveling the corners of the gain, at 49, preferably. Also, preferably, to afford better drainage from the mechanism, the gain 22 is deepened from front .to rear, so that entrance of water or snow to the interior of the device, or retention thereof, is hindered. The widening and deepening of the gain also facilitates sweeping such substances therefrom.

rlhe front end or head 27 is made convex, with curves of ample radius, eXteriorly, and

it preferably Ahas its top `carried somewhat above the upper `surface of ,the main housing top 2O as shown, acting as a fender for the iheads of :the screws 21, with relation to objects thrown or dragged forcibly over the thrice, in accidents such as hereinbefore alluded to, if Acoming toward the front of the installation. The locking means and the treadle being down behind this raised head 2'? and top 20, these are protected in a much `better manner than they yare in switch devices having the locking and operating Ameans substantially above the top of `the head block. Against collision of objects coming from th-e opposite direction, the other head bock 18a offers considerable protection, `as also does the switch-stand structure, which might :be disrupted but would itend .to divert the colliding object `up and over the interlocking device. Also, the most danger is present from such collisions in switch-facing direction; as a freeing lof the point rails makes derailment certain, whereas such an accident with the train running in opposite direction would still permit the wheel flanges to overcome the rail displacements. vAlso, in the cases of vehicles ,being thrown by trains against the switch-stands, at road crossings, the switches almost al Tays face the crossings, so that the collision is in facing direction. Itis for these .reasons that l present ,the more eifective guards in opposition to Aapproach in switch-facing direction, as disclosed.

ln conformity with this plan, l also pro` vide a guard or casing over and around that .part of the interlocking bar 1 between the stock rail 34 and the housing 19, and also, preferably, an additional or terminal guard section or .casing 51 over and around the end part of .the bar 1 out past the housing 19 (Fig. It will be seen that this interlocking bar 1 is effectively guarded against collisions coming in theopposite dreetion, by the head block 18 itself; but as these hars ordinarily ha've been used, they are entirely exposed to collision coming in switcli-lacing direction, which it is the ob ject of my `guards or casings to counteract. The casing 50 is approximately channel shaped, turned on its side or partly inverted; the upper side 52 being the deeper and overlapping the adjacent top surface of the head block 18, to which it is fastened by screws 58 at intervals therealong. ll7hat would be the bottom of the channel thus forms the front wall of the casing, curving and slant-ing forward and downward over the har 1 at 54 and extending vertically therebelow at 55, 'whence the bottom side 5G o f the channel slopes to the bottom edge of the head block 18 (Fig. against which it may lit rather loosely. The track ballast 57 is packed against the lower vparts of the casing, and no attempt is made t0 close either end thereof, either at the rail 34; or next to the housing 19; the object being to allow free drainage into and out of the casing as the best means of avoiding clogging around the bar 1, by dirt or freezing. Further to facilitate drainage, the bottom side 56 preferably is sloped from the track end outward as seen in Fig. 3; and as this side 5G also inclines to the head block or tie 18, the drainage will be along this inner corner, and partly down into the ballast 57 past the loosely fitting lower edge of the casing. At the same time, this lower side 56, abutting' the tie 18, aords the required lower support for theV front portions 541 and if these receive the impact of a collision, which they tend to divert up over the top of the tie 18 away from the bar 1. If the colliding object catches under the bottom of the casing, to do which, however, it must tear away the ballast 57, it may tear up the casing; but in so doing, the casing, vfixed at its top edge, tends to act as a lever swinging out forwardly and up, to fend the object `away from the bar 1. The terminal casing 51 is similar to the longer section 50 in having a ytog over and screwed to the `tie 18 by screws 58, and a front 59V sloping down and forward over the end part of the bar 1. Preferably its bottom is omitted, to permit better drainage away from the housing 19, and it has an outer closed end 60 and outer terminal flange G1 fastened to the lower part of the head block or tic 18 by the screw G2. lt will be understood that this casing 51 will have its lower edges abutted by the ballast 57 also, although the ballast is not so deep at that place, sloping from the track, for drainage. i

In the modilication of Figs. 7, 8 and 9, it will he understood that the device will be located with relation to the switch-stand as is the device in Fig. 1, and the ,connection ofthe interlocking `bar 1 to the .rail will be similar; and this bar is guarded by the casing 50 (Fig. 4.) with top 52, screws 53, front portions 5 i and 55 and `bottom 56 sloping as does the bottom 5G of the [irst example. Here, the bar 1 has its broader sides upright, and the front portions ofthe casing` 50 vary accordingly from the corresponding parts in the preceding example; especially as the bar v1 is carired considerably nearer the top of the head block 18 thanis the bar 1 of the first example. Also it will be understood that this bar 1 may have a suitable terminal `guard or casing, not shown, inst as with the bar of the example before described.

The different location of the bar 1 is in accordance .with the different relation of the plunger that engages with it. Thus, `the housing 19 comprises the top 20 from vthe front of vwhich depends .the stirrup-head 23 having the transverse rectangular .opening 24 through which the bar l slides in its movement with the switch point rail such as the rail 4. The head 23 has the bore 30 forward into the opening 24, with a continuation 29 at the front side of the opening 24', not, however, continuing out through the front of the head, which is left amply massive in front of the opening 24 to provide a strong cover -for the front end of the plunger 3l which slides in these bores 30 and 29 and, when the bar l registers its opening 33 with the bores, upon correct closure of the switch, slides through the bar as illustrated, in a horizontal direction instead of vertically as in the lirst example.

The housing top 20, which bridges the gain 22 in the head block 1S', has, some distance from its rear end, the depending wall member 63 fitting down across the gain and having a bore G4 alined with the bores 29 and 30, guiding the rear or head end part of the plunger 31, which has a collar 65 pinned on it and a helical spring 66 around it between the collar G5 and the wall member G3, forcing 'the plunger 3l forward until the collar engages the rear side of the head 23 as the plunger reaches its greatest forward extension through the interlocking bar l. A rib 67 from the head 23 back to the wall member 63 on the lower side of the top 20 reinforces the top and head connection. A deeper rib 68 extends back from the wall member G3 on the lower' side of the top 20; and the intermediate lever 69, which comprises side members joined by a neck 70 (Fig. 8) has the upper ends of its members straddling this rear rib G8, with the fulcrum pin 71 transversely through them and the rib. The lower ends of these intermediate lever members straddle the head or eye 32 of the plunger 3l', with a pin 72 transversely through them and the eye. To the rear of and above the ne-ck 7 O, these members take the form of segments 42. rlhe locking ear 43 projects back from the rear end of the top 20 and rear rib 68, with a transverse opening 44 which is covered by the lever segments 42 'as these swing up on backward swinging of the lever 69 to withdraw the plunger 3l from the bar 1, preventing insertion of the padlock bow, which can be inserted in the opening 44 only if the plunger is safely through the bar 1, upon which the bow, engaging the upper edges of the segments 42, prevents withdrawal of the plunger. Opposite the junctions of its side members with the neck 70, the intermediate lever G9 has laterally projected wings 72 (Fig. 9) and a bottom plate 73 projects back from the bottom of the wall member 63, fitting in the bottom of the head block gain 22', and has on its rear end a hub 74 straddled by the forked lower end of the treadle lever'7 5,

with a fulcrum pin 7 6 transversely through the fork members and hub. This treadle lever 75 also has a forwardly projected pair of fork members 77, straddling the intermediate lever 69 and engaging up againstthe wings 72 thereof, so that when this treadle lever is swung backward by pressure on the treadle 7 8 on its upper rear end it swings the intermediate lever backward, withdrawing the plunger 3l against the pressure of the spring 6G, which returns the plunger into engagement upon release of the treadle and registry of the interlocking bar opening 33 with the housing openings 29 and 30.

In this example, a rib 79 extends from the stirrup-head 23 down to the bottom of the front stirrup plate 80, from the bottom edge of which the housing bottom plate 81 preferably projects under the bottom of the tie or head block 18. Four bolts 2l pass entirely through the bottom plate 81, head block 18, and housing top 20; two bolts being at each side of the gain 22', which is suitably tapered for access and drainage, as in the gain 22 of the first example. This bolted-through connection affords an even stronger attachment of the housing to tlie head block than the distribution of screws 21 above and screws 26 below in the previous example; and is another illustration of the principle of fixing the housingv not only to the top of the tie but to its bottom, as by the screws 26 in the other illustration. Also,

it will be obvious that either kind of bot tom attachment may be used with either kind of mechanism. The bolted-through connection is stronger; but requires considerable excavation under the tie to allow insertion of the bolts as illustrated, or application of the nuts, where they passed through from the top.

It will be noted that, in either example, there is no exposure of the plunger' 3l or 3l at the front, or in an upper exterior part of the device; affording much greater security than is to be had in previous dc vices having the'plunger end exposed at the front, which if struck might be forced back out of the bar; or, in those devices having a vertically moving plunger, its support is exposed above the head block, in danger of complete displacement. In the second example, the spring actuation of the plunger is more positive than the gravity actuation in the first example; but if the spring breaks, the second device lacks automatic return of the plunger to locking position, although, with the padlock in place, the plunger can be securely held engaged until a new spring is installed. Of course spring actuation is not confined to horizontal plunger movement; or gravity may be made to actuate a plunger horizontally; examples of either variation being found `in the prior ittica-ilse art. Blut I have sought to illustrate two leading types of plunger operation embodied in my invention having the advantages of security lacking in any oi the prior art examples. Also the prior art will show means other than treadlesl :tor alaplfying power to the mechanism; but the examples as illustrated, both with treadlesi suiiiciently exemplify the advantages ci my in- Vention, to which the modiiicatiions of power application.may be applied without departing `from its scope. Similarly; other modiiications may occur in practice, and theretore, while I have somewhat specifically illustrated and described preferred embodiments of my invention,v I doY not wish to be understood asy being limited to such precise disclosure, but having thus fully described my invention, whatfI claim as' new and desire to secure 1by Letters Patent is l. A switch interlocking device comprising' positively engaging interlocking elements' and operating` means for one oi said elements, said interlocking elements and said operating," means being entirely below the level oi the top of the switch head block.

2'. A switch inteilook'ing device comprising interlocking elements and operating means for one of said elements, said i`nte`rlocking elements and saidoperating means beingr entirely below' the level of the top of the switch head block and the other one or said interlocking elei'n'entsv being alongside the head block; and means'E covering this other one oi said eleinentsl 3; A switch interlocking device comprising ii'iterlocking elements and operating means for one of said elements, said interlocking elements" and said operating means heilig entirely below the level of the' top of the switch head block,- and means for locking said operating' means" below the level of the top of the head block.

4. A switchI interlocking device comprising interlocking elements,` operating means for' one of said elements,v and al housing for said operating means liavi'n'g its top extended along and fixed tothe top* oi the switchV head block, said interlocking elements and said operating meansbeing entirely below the level of thetop of thehead block.

5; A switch interlocking mechanism comprising an interlocking bar and a plunger engaging said bar below the level' of the top of the switch headvblo'ck, and a lever con'- ne'cted to said plunger and havingI its ful-` crum below the level of the top of the head block.

6. A switch interlocking' device comprising an interlocking bar and mechanism with a part at one end to retentively engage said bar, said mechanism extending along the track from said bar, and locking means for said mechanism at the opposite end of said mechanism.

switch interloeking partly embedded in and partly along one side of the switch head block and comprising means for locking said mechanism below the level of the top of and near the opposite side of the head block.

9. A switch interlocking mechanism comprising an interlocking bar and a plunger engaging said bar below the top ci the switch head block, and a housing for said bar and plunger having itsrtop extended along and fixed to the top of said head block.

10. A switch interlocking mechanism comprising an interlocking bar and plunger engaging said bar below the top oiz the switch head block, said head block having a gain' admitting part oi said mechanismy and having the bottom of said gain sloping from said bar and plunger.

1l. A switch interlocking mechanism comprising anA interlocking bar and a plunger engaging said bar below the top of the switch head block, said head block having a gain admitting part of said mechanism and having said gain increasing in width from' said bar and plunger, and a treadle on said mechanism inthe wider part of said gain.

12. A switch interlocking mechanism comprising an interlocking bar and a plunger engaging said bar below thel top of the switch head block, saidA head block having a gain admitting part of said mechanism, a treadle on said mechanism in said gain, and means for locking's'aid mechanism in said gain,V said treadle andv said locking means lying below the' top of said head block.

13: A switch interlocking mechanism comprising anv interlocking bar and a plunger engaging said bar below .the ,top of the switch head block, and a housing ior said bar and plunger entirely surrounding said plunger laterally and having its top extended along and fixed tothe top of said head block.

14. A switch interlocking mechanism comprising an interlocking bar and a plung er engaging said bar below the top of the switch head' block, a' housing for said bar and plunger entirely surrounding said plunger laterally and having its top extended along the top' of said head block, and fastening means securing said housing top to said head block, said housing being higher than said fastening means adjacent to said bar and plunger.

15. A switch interlocking mechanism comprising an interlocking bar and a plunger engaging said bar below the top of the switch head block, a housing for said bar and plunger entirely surrounding said plunger laterally and having its top extended along the top of said head block, and fastening means secru'ing said housing top to said head block, said housing comprising a head adjacent to said bar and plunger', outwardly convex and higher than said fastening means.

1G. A switch interlocking mechanism comprising an interlocking bar and a plunger engaging said bar below the top of the switch head block, and a housing` for said bar and plunger having` its top extended along and fixed to the top of said head block and having an extension fixed to said head block near the bottom of said head block.

17. A switch interlocking device comprising an interlocking bar connected to a rail of the switch, means to retentively engage with said bar below the level of the top of the switch head block, and operating means for said retentively engaging means entirely below the level of the top of the head block.

1S. A switch interlocking device comprising an interlocking bar connected to a rail of the switch, means operated to retentively engage with said bar below the level of the top of the switch head block, and means for applying a padlock to prevent operation of said retentively engaging means, entirely below the level of the top of the head block.

19. A switch interlockingdevice comprising an interlocking bar connected to a rail of the switch, extending along the switch head block below the top thereof, and a casing extending along said head block and overlapping said bar.

20. A switch interlocking device comprising an interlocking bar connected to a rail of the switch, extending along the switch head block below the top thereof and at one side thereof, and a casing of channel crosssection extending along said head block and overlapping said bar, said casing having one side of the channel fixed to the upper part of the head block, and having the edge of the other side of the channel presented toward said side of said head block near the bottom of said side.

21. A switch interlocking device comprising an interlocking bar connected to a rail of the switch, extending along the switch head block below the top thereof and at one side thereof, and a casing extending along said side of said head block around said bar and having a bottom sloping from the switch rail outward.

22. A switch interlocking device comprising an interlocking bar connected to a rail of the switch, extending along the switch head block below the top thereof and at one side thereof, and a casing extending along said head block around said bar and having a bottom sloping from the switch rail outward and also sloping toward and loosely engagingwith said side of the head block near the bottom of said side.

23. A housing for switch interlocking mechanism comprising a top to lie on the top of the switch head block, and a stirrup at onevend of said top to receive the interlocking bar of the mechanism.

2st. vA housing for switch interlocking mechanism comprising a top to lie on the top of the switch head block, and an extension at one end of said top to receive the interlocking bar of the mechanism, said extension also having an opening under said top to admit a plunger to the bar, but being closed on all sides out from under said top.

25. A housing for switch interlocking mechanism comprising a top to lie on the top of the switch head block, and an extension at one end of the top to receive the interlocking bar and plunger of the mechanism, and having a downward extension to enter a gain in the head block for supporting part of the mechanism.

26. A switch interlocking mechanism to be mounted on the switch head block, comprising an interlocking bar and a plunger at one side of the head block, operating means for the plunger extending across the head block, and means near the opposite side of the head block for applying a padlock to said operating means.

27. A switch interlocking device comprising interlocking elements and voperating means for one of said elements, said operating means extendingthrough the switch head block from side to side thereof entirely below the level of the top thereof.

28. A switch interlocking device comprising interlocking elements and operating means for one of said elements, said interlocking elements having their interlocking engagement near one side of the switch head block and both of said elements and said operating means being entirely below the level of the top of the head block, and means near the oppositeside of and below the level of the top of the head block for locking said operating means.

JOI-FN T. MGGARRY.

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