US2320171A - Railway switch operating apparatus - Google Patents

Description

May 25, 1943. H. L. BONE RAILWAY SWITCH OPERATING APPARATUS 2 Sheets-Sheet l INVENTOR [14 'n/ I L. [50110 [/[VA'i'TORNE-IY Filed April 8, 1941 May 25, 1943. H. L. BONE 2,320,171

' RAILWAY SWITCH OPERATING APPARATUS I Filed April 8, 1941 2 Sheets-Sheet 2 INVENTOR Patented May 25, 1943 RAILWAY SWITCH OPERATING APPARATUS Herbert L Bone, Forest Hills, Pa., assignor to The Union Switch & Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application April 8, 1941, Serial No. 387,385

18 Claims.

My invention relates to railway switch operating apparatus, and particularly to railway switch operating apparatus of the so-called dual-control type in which means are provided for operating a switch either by power or by hand depending upon the position of a manually operable selector lever.

One object of my invention is the provision, in apparatus of the type described, of a new and improved dual-control mechanism the manual operation of which is normally effective to cause the switch to become locked in either extreme position to which it is moved in the same manner that the switch becomes locked in either extreme position to which it is moved in response to power operation of the mechanism, but which mechanism is so arranged that the hand throw lever can, by proper manipulation of the selector lever, be rendered effective to move the switch points to, and hold them in, either extreme position, without moving the locking plunger to its locking position. This operation is advantageous, since in the ordinary applications of dual-control switch and lock movements, the signals governing trafiic over the switch are usually controlled by a circuit contrcller operated in part by the locking plunger in such manner that the signals cannot clear unless the switch points are moved to one or the other of their extreme positions and are locked in these positions, and it is normally desirable that the signals should clear in response to manual operation of the switch in the same manner as when the mechanism is operated by power. However. it sometimes happens that the lock rods become fouled. due for example to dragging equipment or to improper maintenance, without the switch being otherwise damaged, and in this event it is desirable to be able to reverse the switch to permit train movements over the switch without having the signals clear.

Another object of my invention is the provi ion in a dual-control mechanism for switch o eratin apparatus of the type described of a new and improved clutch mechanism for operatively connecting the hand throw and power nneliated gear :trains with the main switch operwhile permitting the selector lever to be operated to its full stroke even though the relative positions of the switch, power gearing and hand throw gearing are .not in agreement at the time, will give a positive break-apart" motion guar anteeing separation of the previously engaged drive.

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

I accomplish the aforementioned objects by the details of construction hereinafter set forth.

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. l is a vertical sectional view showing one form of .apparatus embodying my invention. Fig. 2 is a left-hand side view partly in elevation, and partly in section, of the apparatus shown in Fig. 1. Fig. 3 is a sectional view taken substantially on the line III-III of Fig. 2. Fig. 4 is a view partly diagrammatic and partly in horizontal section showing certain parts of the apparatus illustrated in the preceding views connected with a railway switch in the intended manner. Fig. 5 is a view taken on the line V--V of Fig. 4.

Similar reference characters refer to similar parts in each of the several views.

Referring to the drawings, the reference character l designates a housing provided with a removable cover 2, and adapted to be mounted adjacent a railway track switch S shown diagrammatically in Fig. 4. Journaled in vertically aligned bearings 3 and 4 disposed within the housing I is a vertically extending shaft 6, the lower end of which terminates in a crank i. This crank extends in opposite directions from the shaft, and is provided on its lower side with a crank pin 8 carrying a roller 9, and on its upper side with rounded upstanding project ons H3 and II disposed on opposite sides of the shaft. The roller 9 cooperates with a cam slot 2a formed in an operating rod 0, while the projections Ill and H cooperate, respectively, with spaced recesses Na and 1 la. formed in the underside of a slide bar N. The operating rod 0 is slidably mounted in the bottom of the casing I at one side of the axis of the shaft 5 and is operatively connected at one of its outer ends with the switch S. The slide bar N is slidably mounted in the bottom of the casing I in a position in which it intersects the operating rod 0 at right angles, and is provided at its right-hand end with a locking plunger l2 provided with vertically offset and longitudinally main stationary.

spaced locking dogs I20. and 12b which are adapted to selectively enter spaced notches |3a and I31) provided in a lock rod L operatively connected with the switch points of the switch S. The lock rod L is of well-known construction, and is slidably mounted in the bottom of the casing l at right angles to the slide bar N, as is obvious.

The portion of the switch operating apparatus thus far described is essentially the same as that described and claimed in Letters Patent of the United States No. 1,293,290, granted to William Zabel on February 4, 1919, for Railway traffic controlling apparatus, and its operation, briefly described, is as follows: When the operating rod and the slide bar N are in their normal positions, and the switch points of the switch S are in their corresponding positions, as shown in Fig. 4, the locking dog I2a is disposed within the notches I3a in the lock rod L, and under these conditions the switch points are securely locked in their normal positions by the locking dog l2a.

When it is desired to reverse the switch S, the shaft 6 is rotated in a clockwise direction from the extreme position shown to its opposite eX- treme position. The initial part of this rotation, usually about the first 30", causes the projection I B on the crank I to engage the left-hand wall of the recess Illa in the slide bar N, and move the slide bar toward the left far enough to withdraw the locking dog l2a from the notches l3a in the lock rod L. During this initial movement of the crank the roller 9 whose initial position was at the left-hand end of the cam slot 90. is

-moved to the medial portion of the slot, that is to say, to a point just a little to the left of the junction of the curved and straight walls thereof, but due to the curvature of the upper wall of the cam slot, this movement of the roller does not cause any movement of the operating rod 0.

It will be seen, therefore, that during the first part of .the movement of the crank l, the slide bar N is moved to unlock the switch points, but the operating rod 0 and the switch points re- However, in the continued movement of the crank, the roller 9 engages the lower straight side of the cam slot 9a and moves the operating rod- 0 in the direction that the crank is moving to thereby move the switch points to their reverse positions. This latter or intermediate movement of the crank will usually rotate the crank through an angle of approximately 180. Upon further continued movement of the crank, projection H enters the recess Ila and imparts a second movement to the slide bar N in the same direction as the first movement, which latter movement causes the locking dog l2b to enter the notches I 317 in the lock rod L and lock the switch in its reverse position.

When the parts have been operated to the positions just described, and the crank is rotated in a counterclockwise direction to restore the parts to the positions shown, the sequence of movements of the operating rod and slide bar are maintained, but the directions of the movements are reversed.

For convenience I shall hereinafter refer to the initial movement of the crank from either extreme position towards the other as the unlocking stroke, the intermediate portion as the switch operating stroke, and the final movement as the locking stroke.

It should be particularly pointed out that with the apparatus constructed in the manner just described, upon the completion of the switch opcooperation between the roller and the operating 7 rod, in the extreme position it then occupies irrespective of the fact that it is unlocked. It follows, therefore, that if suitable precautions are taken to prevent the crank from creeping upon the completion of the switch operating stroke, trains can be safely moved over the switch even though it is not locked by the locking plunger. One way for preventing the crank from creeping which can be used consists in providing the operating motor M of the mechanism shown diagrammatically in Fig. 2, with a magnetic brake similar to that shown and described in Letters Patent of the United States No. 2,183,164, granted to William C. McWhirter et al. on December 12, 1939, for Railway switch operating apparatus.

A main bevel gear I5 is rotatably mounted on the shaft 6 directly above the lower bearing 4, and is operatively connected with power driving means here shown as the electric motor M,

through suitable reduction'gearing indicated in,

in turn, is rotatably mounted in a boss 49 pro vided in the wall of the casing l. The shaft 2! projects through the sleeve 22.and carries at its outer end a hand throw lever 23 which is at times used for manual operation of the switch.

In accordance with my present invention, novel and improved means are provided for selectively connecting the bevel gear IE5 or the bevel gear I! with the switch actuating shaft 6 to permit the switch to be operated either by the electric motor M or by the hand lever 23. As 'here shown,--these means comprise a clutch assembly A consisting of two sleeves 24 and 25 which are mounted on the shaft 6 for vertical sliding movement between the two gears l5 and H, but which are constrained to rotate with the shaft 6 by means of integral internal splines 25 which cooperate with corresponding plines 21 formed on the shaft. The two sleeves 24 and 25 are secured together at their confronting ends to cause them to act as a unit, and are provided at their upper and'lower ends, respectively, with circumferential flanges 24a and 250. which form confronting shoulders 24b and 25b. Surrounding the sleeves 24 and 25 between the shoulders 24b and 25b is a compressed coil spring 28. One end of the spring engages a flat spring thrust washer 26 and constantly urges it to the position in which it engages the shoulder 24b, and the other end of this spring engages a cupped spring thrust washer 21 and constantly urges it to the position in which it engages the shoulder 25b.

The lower end of the sleeve 25 is formed with tapered projections 29 which cooperate with tapered recesses 30 provided in the hub of the bevel gear 6, whereby when the clutch mechanism is in its lower position as shown, the shaft 6 is connected to the main bevel gear IE to enable the mechanism to be power operated in the nor- 38 will act through the spring thrust washer 26 to exert a force on the spring 28 which causes it to become compressed and bias the clutch assembly to its lowermost position. As a result, as soon as the bevel gear I is rotated by the motor to the positions in which the projections 29 align with the recesses 30, the clutch will immediately snap to its lowermost position in which it is shown in the drawings.

When the switch is in condition for motor operation, the bevel gear I! is disconnected from the switch actuating shaft 6, and the hand throw lever is therefore disconnected from the switch.

When it is desired to disconnect the motor from, and connect the hand throw lever 23 with the shaft 6, the selector lever is rotated from the motor operating position in which it is shown in the drawings to its opposite extreme or hand throw position. This rotation acts through the sleeve 22 and the gears 44 and 43 to rotate the shifter shaft 39 from the position shown through an angle of 180 to the position in which the axis of the central enlarged portion of the shaft is disposed at the highest point in its travel, and hence causes the shifter fork to rotate from its lowermost to its uppermost position. During this rotation the lower roller 38 on the shifter fork engages the underside of the flange 21a 0n the spring thrust washer 21 and moves it upwardly with the shifter fork. The upward movement of the spring washer, in turn, exerts a force on the spring 38 which is transmitted through the spring and thrust washer 26 to the interconnected clutch sleeves, and under normal conditions, this force will cause the sleeves to move upwardly as soon as the shifter fork starts to move. However, should the switch operating apparatus happen to be standing with the power gear train stopped by the inertia of therotating parts upon the completion of the previous reversal of the movement, the static torque which then exists between the engaging sides of the projections 29 and recesses 30, may be sufficient to prevent the assembly from starting to move upwardly even though spring 28 becomes fully compressed. The parts are so proportioned that under these latter conditions, the flange 21a will move into engagement with the spring washer 26 before the shifter fork reaches its upper extreme position, and when this happens, a positive force will be exerted on the clutch sleeve which force is sufficient to overcome the static torque between the lower sleeve and the gear wheel l5, and will thus cause the clutch assembly as a whole to move upwardly under the bias of the compressed spring 28.

When the clutch assembly starts to move upwardly, if the narrow portion 32a of the recess 32 in the bevel gear I! is then in alignment with the projection 3| on the sleeve 24'. as will be the case when the switch and hand lever occupy corresponding extreme positions and the switch is fully locked in the extreme position it then occupies, the spring 28 will act to cause the clutch to move to its upper extreme position in which the projection 3| enters the narrow portion of the recess 32. The bevel gear will then be connected with the shaft 6 in such manner that the switch may be rotated between its two extreme positions and locked in either extreme position to which it is moved by the hand lever in the same manner that it is rotated between its two extreme positions and is locked in either extreme position by power operation. If, however, the narrow portion 32a of the recess 32 in the bevel gear I! is not in alignment with the projection 3| on the sleeve 24 of the clutch assembly when the clutch assembly starts to move upwardly, the spring 28 will then act to move the clutch assembly to the position in which it enters the wide portion of the recess 32, but full upward movement of the clutch will be prevented. Under these conditions, the spring 28 will become compressed, and as soon as the hand throw lever is rotated to the position in which the narrow portion 32a of the recess 32 aligns with the projection 3|, the spring 28 will act to force the clutch assembly to its full upper position. This alignment of the narrow portion of the recess with the projection 3| will always occur at some point in the stroke of the hand throw lever, and if the switch happens to be in a position opposite to that of the hand throw lever when the selector lever is operated to the hand throw position, then the hand throw lever will rotate freely without engaging the clutch until the hand throw lever is fully reversed. I shall now assume that the lock rods of th switch have become damaged or are out of adjustment, but that the switch is otherwise in op erating condition, and that it is desired to reverse the switch by hand without looking it up. To accomplish this result, the operator will move the selector lever to the hand throw position in the manner previously described, and will then operate the hand throw lever. If the parts are.

in such positions that the projections 3| on the upper clutch sleeve 24 enter the wide portion 32b of the recess 32 in the bevel gear ll when the selector lever is reversed, then the hand throw lever upon being reversed will just rotate the switch operating shaft to the end 'ofthe switch'operating stroke, and the desired result will be obtained without further manipulation of the mechanism. If, however, theprojectlon 3| enters the narrow portion of the recess 32 in response to movement of the selector lever-to its hand throw position, then when the hand throw lever is subsequently operated, its movement will be arrested when the switch actuating shaft reaches the position in which the locking dog fouls the lock rod. Under these latter conditions, it is desired to be able to completethe stroke of the hand throw lev er, and-this result may be.ac'-

complished by lifting the selector lever to its vertical position. This movement will force the clutch assembly downwardly to the position in' which the projection 3| moves out of the narrow portion 3211-01 the recess'32 and into the wide portion 32b, and as soon as the projection 3| is clear of the narrow portion 32a of the recess 32, the hand lever 23 will drop by gravity to its full stroke position. The selector lever may then be restored to either the motor or hand throw position as desired. When the hand throw lever reaches its full stroke position, it will be held in this position by the usual lever latch stand, not shown, and since the roller 9 will then be within the curved portion of the cam slot 9a in the operating rod 0, the switch will be securely held 7 it is damaged or obstructed to such an extent that the operating rod 0 cannot complete its full stroke, the hand throw lever cannot be forced into the latch stand even if the selector lever is operated to cause projection 3| to enter the wide portion 32b of recess 32. This is due to the fact that the lost motion provided by the wide portion 321) of recess 32 is only sufiicient to permit the hand throw lever to enter the latch stand when the operating rod has fully completed its stroke. The fact that the hand throw lever cannot enter the latch stand indicates to the switchman that the switch is not in proper condition for train movements over it.

The switch operating apparatus will usually in-. clude a circuit controller, not shown, which may be similar to that described in Patent. No. 1,293,290 referred to hereinbefore. This. circuit controller may beused to govern signals con-. trolling trafiic movements over the switch operated by the mechanism, and when so used it will be apparent that the signals will only clear when the switch occupies one or the other of its extreme positions and is fully locked in such extreme position.

It follows from the foregoing that my present inventionprovides for the manual operation of a power operated switch in such. a way that the switch will normally become locked in response to manual operation to cause the signals to clear in the same manner as when the switch is operated by power, but that, in the event of lock rod fouling, if the switch is otherwise undamaged, it can, by proper manipulation of the apparatus, be reversed without looking the switch in its reverse position.

The apparatus also includes means for interlocking the selector and hand throw levers in such manner that the hand throw lever cannot be operated unless the selector lever occupies the hand throw position. As here shown, these means comprise cooperating interlocking ,discs 45 and 426' formed respectively on the hub of the gear Wheel 43 and on the hub of the bevel gear 26. 'Disc .45 is provided with an arcuate projection 45a, which, whenthe selector lever occupies its powernoperating position, enters .a. mating arcuate notch 4.6a or 4th in disc 46 according as the handthrow lever then occupies its normal extremeposition in which it is shown in the drawing or its QDPQ- site. extreme position, The length of the pro jection 45a is such that it will remain in, one .1 the other of the recesses 46a or 45b when'the selector lever is rotated towards the hand throw position until the selector lever has been moved to approximately its mid stroke position. It will be apparent that when the projection 4 5a...is within one or the other of the arcuate notchesw Mia and 46b, rotation of the hand throw lever is effectivel prevented, and it follows, therefore, that the discs act to prevent rotation of the hand throw lever except whenthe selector lever is in its hand throw position.

One advantage of switch operating apparatus embodying my invention is that ince the clutch is always eifective to connect either the hand throw lever or the motor operating gear train with the switch operating shaft, the switch-open, ating rod is clearly held from movement regardless of the positions of the selector andhana throw levers. This is of particular significance when the power is off.

Although I have herein shown and described only one form of railway switch operating apparatus embodying my invention, it is understood the spirit and Having thus described my invention, what I claim is:

1. In railway switch operating apparatus including .means responsive to rotation of a main operating shaft to one extent'for unlocking and reversing the switch and to another extent for locking the switch, the combination of manual means and power means for optionally operating said shaft, and selector means for connecting said manual means or said power means with said shaft, said selector means including means for optionally rendering said manual means effective to rotate said shaft to its one or its other extent in response to full stroke operation of said manual means.

2. In combination with an operating rod for operating a railway track'switch and a slide bar for locking the switch, a rotatable shaft for operating the-operating rod in' response to rotation of said shaft to one extent and both the operating rod and slide bar in response to rotation of said shaft to a greater extent, power and manual means for optionally operating said shaft, a clutch effective when 'moved-to'one position to connect said power means to said shaft to enable the shaft to be operated by the power means to its greater extent'and when moved to another position to connect said manual means to said shaft to enable said shaft to be operated by said manual means to its greater extent and when moved to a third position to connect said manual means to said shaft'to enable the shaft to be operated by said manual means to said one extent on y, whereby the switch can be optionally locked or left unlocked following its reversal by said manual means, and means for operating said clutch.

3. In railway switch operating apparatus including means responsive to rotation of a main operating shaft to one extent for unlocking and reversing the switch and to another extent for locking the switch, the combination of manual means and power meansfor optionally operating said shaft, and clutch means for connecting" said manual means or said power meanswith said shaft, said clutch means being movable to two different manual operation'posit-ions in one of which said manual means is effective in response to its full stroke operation to move; said shaft to its other extent and in the other of which said manual means is effective in response to its full stroke operation to 'move said shaft to its one extent only.

4, In railway switch operating apparatus including means responsive to rotation of a main operating shaft to one extent for unlocking and reversing the switch and to another extent for locking the switch, the combination of manual means and power means for optionally operating sa-id shaft, and clutch means for connecting said manual means or said power means with said shaft; said clutch means being movable to two different manual operation positions in one of which said manual means is effective in response to its full stroke operation to move said shaft to its other extent and in the other of which suflicient lost motion is introduced between said manual meansand said shaft to prevent operation of said shaft beyond its one extent by said manual means.

5. Railway switch operating apparatus comprising a rotatable switch actuating shaft, two movablemem-bers associated with said shaft, and a manually operable clutch-associated with said shaft and movable to one position in which the one member becomes connected with said shaft and to two other positions in both of which the other member becomes connected with the shaft, one of said other positions providing some lost motion between said shaft and said other member.

. 6. Railway switch operating apparatus comprising a rotatable switch actuating shaft, two driving members rotatably mounted on said shaft in spaced confronting relation, means for rotating said members, a clutch assembly mounted on said shaft to rotate therewith between said driving members but slidable thereon toward one or the other of said members, means connecting said one member with said shaft when said clutch assembly is moved into engagement with said one member, other means connecting said other member with said shaft with a predetermined amount of lost motion or substantially without lost motion when said clutch assembly is moved toward said other member depending upon the extent to which said clutch assembly is moved toward said other member, and means for moving said clutch assembly along said shaft. I

'7. Railway switch operating apparatus comprising a rotatable switch actuating shaft, a gear wheel rotatably mounted on said shaft and provided with a stepped recess having a wide portion and a narrow portion, a clutch assembly mounted on said shaft to rotatetherewith but slidable thereon toward and away from said gear wheel, said clutch assembly being provided with a projection which is adapted to enter the wide or narrow portions of said recess to cause said gear wheel to become connected with said shaft with or without lost motion depending upon the extent of movement of said clutch assembly toward said gear wheel, and means for sliding said clutch assembly toward said gear wheel to different extents and away from said gear wheel.

8. In railway switch operating apparatus including means responsive to rotation of a main operating shaft to one extent for unlocking and reversing the switch and to a greater extent for relocking the switch, a gear wheel rotatably mounted on said shaft and provided with a stepped recess having a wide portion and a narrow portion, a clutch assembly mounted on said shaft to rotate therewith but slidable thereon toward and away from said gear wheel, said clutch assembly being provided with a projection which is adapted to enter the wide or narrow portion of said recess when said clutch assembly is moved toward said gear wheel depending upon the extent of the movement, and means for rotating said gear wheel between two extreme positions, the parts being so proportioned that rotation of said gear wheel between its two extreme positions will rotate said shaft to its full extent or to said one extent depending upon whether said projection is within the narrow or wide portion of said recess.

9. In railway switch operating apparatus including means responsive to rotation of a main operating shaft to one extent for unlocking and reversing the switch and to a greater extent for relocking the switch, a gear wheel rotatably mounted on said shaft, a clutch assembly mounted on said shaft to rotate therewith but slidable thereon toward and away from said gear wheel, said clutch assembly being provided with means for engaging said gear wheel with lost motion when said clutch assembly is moved toward said,

gear wheel to one extent and without lost motion when said clutch assembly is movedtoward'said gear wheellto' a greater extent, and means for rotating said gear wheel to rotate said shaft to its one' or its greater extent depending upon whether said clutch is moved toward said gear wheel to its one or its greater extent.

10. In railway switch operating apparatus in: cluding a switch actuating shaft, two gear wheels rotatably mounted on said shaft in spacedcon: fronting relation, a hand lever for rotating one of said gear wheels, power means for rotating the other gear wheel, a clutch assembly for selectively connecting said gear wheels with said shaft, said clutch assembly comprising two clutch sleeves mounted on said shaft to rotate therewith but slidable thereon between said gear wheels, said sleeves being secured together to operate as a unit and being provided at their opposite ends with circumferential flanges which form confronting shoulders, a compressed spring surrounding said sleeves between said shoulders, a spring washer disposed between each shoulder and the adjacent end of said spring, and means engaging the outer sides of said spring washers for sliding said clutch assembly along said shaft.

11. In railway switch operating apparatus including a switch actuating shaft, two gear wheels rotatably mounted on said shaft in spaced confronting relation, a hand lever for rotating one of said gear wheels, power means for rotating the other gear wheel, a clutch assembly for selectively connecting said gear wheels with said shaft, said clutch assembly comprising two clutch sleeves mounted on said shaft to rotate therewith but slidable thereon between .said gear wheels, said sleeves being secured together to operate as a unit and being provided at their op-- posite ends with circumferential flanges which form confronting shoulders, a compressed spring surrounding said sleeves between said shoulders, a spring washer disposed between eachlshoulder and the adjacent end of said spring, a shifter said gear wheels, power means for rotating the other gear wheel, a clutch for'selectively connecting said gear wheels with said shaft, said;

clutch being sufficiently long to insure that one or the other of said gear wheels will always-be connected with said shaft, means including a spring for normally shifting said clutch, and means effective in the event of initial resistance to movement of said clutch sufficient to cause said spring to become compressed more than a' predetermined amount for providing a positive initial movement of said clutch.

13. In combination, a switch actuatingshaft, a hand lever and a power .drivenmember for optionally operating said switch actuating shaft, a selector levermovable between a hand operating and a power operating position, a second shaft rotated by said selector'lever, a clutch'as sembly operated by said second shaft for connecting said hand lever or said power driven member with said switch-actuating shaft according as said selector lever is moved to its hand operating or power operating position, and means for preventing operation of said hand lever unless said selector lever is in its hand operating position comprising interlocking discs secured to said second shaft and said hand lever.

14. In combination, a switch actuating shaft, a hand lever and a power driven member for optionally operating said switch actuating shaft, a selector lever movable between a hand operating and a power operating position, a second shaft rotated by said selector lever, a clutch assembly operated by said second shaft for connecting said hand lever or said power driven member with said switch actuating shaft according as said selector lever is moved to its hand operating or power operating position, and means for preventing operation of said hand lever unless said selector lever is in its hand operating position comprising interlocking discs secured to said shaft and said hand lever, the disc secured to said hand lever being provided with arcuate notches and the disc secured to said shaft being provided with an arcuate projection which enters the one notch when and only when said selector lever occupies its motor operating position and said hand lever occupies its one extreme position and which enters the other notch when and only when said selector lever occupies its motor operating position and said hand lever occupies its other extreme position.

15. In combination, a switch actuating shaft, a handlever and a power driven member for optionally operating said switch actuating shaft,

a selector lever movable between a hand operating and a power operating position, and a clutch for connecting said hand lever or said power driven member With said switch actuating shaft according as said selector lever is moved to its hand operating or power operating position, said clutch normally being connected with said selector lever through resilient means and being so constructed that operation of said clutch by said selector lever will not simultaneously dis connect said shaft from both said hand lever and said power driven member, and non-resilient means operable by said selector lever in response to initial resistance to movement of said clutch in excess of that which said resilient means when stressed a predetermined amount will overcome for effecting a positive initial movement of said clutch.

16. Railway switch operating apparatus comprising a rotatable switch actuating shaft, two movable members associated with said shaft, a clutch associated with said shaft and movable to one position in which one member becomes connected with said shaft and to another position in which the other member becomes connected with said shaft, resilient means normally effective for shifting said clutch, and non-resilient means effective to produce a positive initial movement of said clutch in the event of initial resistance to movement of said clutch in excess of that which said resilient means when stressed a predetermined amount will overcome.

17. Railway switch operating apparatus comprising a rotatable switch actuating shaft, two movable members associated with said shaft, a clutch associated with said shaft and movable to one position in which one member becomes connected with said shaft and to another position in which the other member becomes connected with said shaft, and means for shifting said clutch including means to yieldably move it if it offers less than a predetermined resistance to movement and other means for non-yieldably moving it through a predetermined initial part of its movement if it offers more than a predetermined initial resistance to movement.

18. In railway switch operating apparatus including a switch actuating shaft, two gear wheels rotatably mounted on said shaft in spaced confronting relation, a hand lever for rotating one of said gear wheels, power means for rotating the other gear wheel, a clutch assembly for selectively connecting said gear wheels with said shaft, said clutch assembly comprising two clutch sleeves mounted on said shaft to rotate therewith but slidable thereon between said gear wheels, said sleeves being secured together to operate as a unit and being provided at their opposite ends with circumferential flanges which form confronting shoulders, a compressed spring surrounding said sleeves between said shoulders, a spring washer disposed between each shoulder and the adjacent end of said spring, a shifter fork pivotally supported at one end and provided at th other end with arms which straddle said clutch assembly, a pair of rollers on each arm cooperating with the outer sides of said two washers respectively, and means for rotating said shifter fork about its pivot to move said clutch assembly between the positions in which it connects said gear wheels with said shaft, the one spring washer being cup shaped and being formed with a flange which engages the other washer before the shifter fork reaches the end of its stroke in the event said clutch assembly offers sufficient initial resistance to movement to compress said spring more than a predetermined amount.

HERBERT L. BONE.

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