US2175593A

US2175593A - Railway switch operating apparatus

Info

Publication number: US2175593A
Application number: US176836A
Authority: US
Inventors: Herbert L Bone
Original assignee: Union Switch and Signal Inc
Current assignee: Hitachi Rail STS USA Inc
Priority date: 1937-11-27
Filing date: 1937-11-27
Publication date: 1939-10-10
Anticipated expiration: 1956-10-10

Description

Oct. 10, 1939. BONE RAILWAY SWITCH OPERATING APPARATUS Filed Nov. 2'7, 193'? 5 Sheets-Sheet l INVENTOR H9117 L .5009.

HS ATTORNEY Oct, 10, 1939 BONE 2,175,593

RAILWAY SWITCH OPERATING APPARATUS Filed Nov. 27, 1937 5 Sheets-Sheet 2 H15 ATTORNEY Oct. 10, 1939. BONE 2,175,593

RAILWAY SWITCH OPERATING APPARATUS Filed Nov. 27, 1937 5 Sheets-Sheet C5 Fi .5. 5; W F

INVENTOR (2U HOP/71?! peril i012 .j

Oct. 10, 1939. g BQNE 2,175,593

RAILWAY SWITCH OPERATING APPARATUS Filed Nov. 27, 1957 Sheets-Sheet 4 F A I O I I O Q 0 U2 II 1' u k 159 117 V2 J: 156 I18 114 113 0 :H-- a l 71 A I f 120 122 y I INVENTOR Fly. 7 Hgpj; L 190126 1 115 ATTORN EY Oct. 10, 1939. H. BONE RAILWAY SWITCH OPERATING APPARATUS Filed NOV. 27, 1937 5 Sheets-Sheet 5 Jwz'zolz.

Fomeexerdan H15 ATTORNEY Patented Oct. 10, 1939 UNITED STATES PATENT OFFICE RAILWAY SWITCH OPERATING APPARATUS Application November 27, 1937, Serial No. 176,836

19 Claims.

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

More particularly, my present invention relates to apparatus of the type in which there is mounted in a single housing manually operable means for moving the switch between its two extreme positions, means for biasing the switch to whichever extreme position it is moved by said manually operable means, means for locking the switch in one of its extreme positions in such manner that it will become automatically unlocked when a train trails the switch, and means effective when a train trails the switch to force the movable rails of the switch to, and hold them in, positions opposite to their initially set positions until after the train has completely passed the switch, whereupon the movable rails are permitted to return to their initially set positions.

One object of my invention is the provision in apparatus of the type described of pneumatic means actuated by the movement of the switch when a train trails the switch for forcing the movable rails to their trailed positions and holding them there until after the trailing train has passed the switch.

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

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

In the accompanying drawings, Fig. 1 is a top plan view showing a railway switch A provided with one form of switch operating mechanism embodying my invention. Fig. 2 is an enlarged view, partly in section and partly in elevation of the operating mechanism shown in Fig. 1. Fig. 3 is a top plan view of the mechanism shown in Fig. 2, certain of the parts being removed and others being shown in section, to better illustrate the construction of the remaining parts. 'Fig. 4 is a diagram illustrating by characteristic curves the operating characteristics of the mechanism shown in the preceding views. Fig. 5 is a sectional view of the spring unit 35 forming part of the mechanism shown in Figs. 2 and 3. Fig. 6 is a view similar to Fig.3 showing a modified form of apparatus embodying my invention. Fig. 7 is a sectional view of a portion of the apparatus shown in Fig. 6. Fig. 8 is a diagram showing by characteristic curves the operating characteristics of the mechanism shown in Fig. 6.

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

Referring first to Fig. 1, the reference character A designates a railway switch comprising, as usual, two fixed rails I and Ia and two

movable rails

2 and 2a.. The fixed rails I and Ia are laid on tie plates 3 and are secured to crossties 4 in the usual manner. The

movable rails

2 and 2a are fastened together by a front rod 5, a head rod 6, a bridle rod I, and a tie rod 8, and may be moved into a normal or a reverse position by means of an operating rod 9 which is connected with the head rod 6 through the medium of the usual switch basket I0. When the switch occupies its normal position in which it is shown in Fig. 1, the movable rail 2 engages the fixed rail I, and the movable rail 2a. is spaced from the fixed rail Ia. When the switch is reversed, however, the movable rail 2a then engages the fixed rail Ia, and the movable rail 2 is spaced from the fixed rail I,

Associated with the switch A is a switch operating mechanism B embodying my invention. As here shown, this mechanism comprises a suitable casing II which is bolted or spiked to the ties4 adjacent the outer side of the rail I, and which is provided with suitable removable covers I2 whereby convenient access to the interior of the casing for inspection or repair of the mechanism may be had.

Extending downwardly through the casing II is a rotatable spindle or switch actuating shaft I6, and attached to the lower end of this shaft is a crank H which is pivotally connected with the previously described operating rod 9, the parts being so proportioned that rotation of the shaft I6 through an angle of approximately 90 will move the switch between its normal and reverse positions.

The portion of the shaft I6 which is disposed within the casing II is made round, and is journaled in a bearing I8 provided in the bottom of the casing II and. in a rotatable sleeve or star block I9 which sleeve, in turn, is journaled in a bearing 20 formed in the top of the casing II. The portion of the shaft I6 above the top of the star block bearing, however, is made square and has a somewhat smaller cross sectional area than the low portion of the shaft.

Secured to the square portion of the shaft I6 is a square sleeve ZI, and slidably mounted on this sleeve is an outer sleeve 22 which is provided with a square opening to receive the inner sleeve so that both sleeves and the shaft are constrained to rotate together. When the outer sleeve 22 occupies its lowermost position on the inner sleeve, in which position it is shown in the drawings, a squared portion 23 formed on the lower end of the outer sleeve enters a squared recess or socket 124 formed in the upper end of the star block i9, and under these conditions, the outer sleeve, and hence the shaft I6, is connected with the star block so that any rotation of the shaft will cause corresponding rotation of the star block. When, however, the outer sleeve 22 is moved to an upper position on the inner sleeve, the squared portion 23 on the lower end of the outer sleeve becomes disengaged from the socket 24 in the star block, and the two sleeves and the shaft are then free to rotate as a unit independently of the star block.

The outer sleeve 22 is arranged to be moved between its two extreme positions by means of a hand lever 21 which also serves as a means for rotating the switch actuating shaft I6 between its two extreme positions. This lever is bifurcated at one end, and the bifurcations thereof are disposed on opposite sides of a squared portion formed at the upper end of the outer sleeve, and are pivoted at their free ends on a pin 28 mounted in a lug 29 formed on the inner sleeve 2|. Each bifurcation extends between a pair of lugs 30 which are secured to the associated side of the outer sleeve 22, only one pair of lugs being visible in the drawings. The parts are so proportioned that, when the lever 2'! is rotated about the pin 28 to a depending position in which it is shown in the drawings, the outer sleeve 22 will be moved to its lowermost position on the inner sleeve, but that, when the lever is rotated about the pin 28 to a substantially horizontal position, the outer sleeve will then beimoved to its upper position on the inner sleeve. It follows that the switch actuating shaft IE will be connected with or disconnected from, the star block IQ according as the lever 21 occupies its depending or its horizontal position, and that, when the lever occupies its horizontal position, the shaft l6 may be rotated between its two extreme positions to move the switch points to their corresponding extreme positions by rotating the lever about the axis of the shaft, without causing rotation of the star block.

When the hand lever 21 occupies its depending position which position is its normal position, it may be locked in this position by placing a padlock 3! or other suitable locking device through a hole 320. formed in the outer end of a lug 32 which is fastened to the outer sleeve 22, and which passes through a suitable slot 33 in the lever 21. A suitable signal, here shown as a pair of vanes 34, positioned 90 with respect to each other in plan View, is fastened to the outer end of the switch actuating shaft l6, and serves to accurately indicate at all times the position of the switch.

The star block l9'is constantly biased to the position in which it is shown in the drawings by means of two biasing devices or

spring units

35 and 35 which are disposed in the casing ll. These biasing devices are similar and a description of one will therefore suffice for both. Referring particularly to the biasing device 35 shown in Fig. 5, this biasing device comprises a cylindrical housing 31 which is provided at one end with a pair of spaced lugs 33, and at the other end with an end plate 39. Located within the housing 31 are two coil springs 45 and M. Interposed between the left-hand end of the

springs

45 and 4| and the end plate 39 is a member 42 having a centrally located hole 43. A similar member 44 provided with a centrally 10- cated hole 45 is interposed between the other end of the springs and 4| and the right-hand end of the housing 35. A rod passes through the

holes

43 and 45 in members 42 and 44 and also passes through a hole 41 in end plate 39. The upset end 48 of rod 46 engages the outer surface of the member 43. Threaded on rod 45 is a sleeve 49 which enters the hole 41 in the end plate 39 and bears against the outer surface of the member 42. into or out of the casing 35 until the springs 45 and H are under the desired pressure, and the end plate is then looked in its adjusted position by bolt 58. Sleeve 5| is then screwed onto rod 46 until it engages the member 52 when the upset end 48 of the rod is tight against the member 44. Sleeve 5! is then locked in its adjusted position by means of the nut 52. With the biasing devices constructed in this manner, it will be apparent that the two springs and M both act to bias the rod 45 to the position shown, and that movement of the rod in either direction will act to compress these springs beyond their initial compression.

The one end of the spring unit 35 is pivotally i attached to the casing H by means of a pin 53 which passes through aligned apertures in the lugs 33, and the one end of the spring unit 36 is similarly attached to the casing H by means of a pin 5%. The free end of the rod 45 of each 'u of the

spring units

35 and 36 is operatively connected with the star block [9 by means of a pin 55 which passes through an eye 56 screwed onto the rod, and through aligned apertures in vertically spaced lugs 5'! provided on the star block.

as viewed in Fig. 3, through an angle corresponding to the switch stroke, the force exerted on the star block by the biasing device 35 will continue to increase as the star block approaches its clockwise extreme position, but the biasing device 36 will function as a toggle, and will act to oppose the movement of the star block until the star block has been rotated approximately halfway to its clockwise extreme position, whereupon the biasing device 36 will then act to assist the further movement of the star block. The parts are still further so proportioned that, if the star block is rotated away from the position shown in a counterclockwise direction as viewed in Fig. 3, through an angle corresponding to the switch stroke, the force exerted on the star block by the biasing device 35 will continue to increase as the star block approaches its counterclockwise extreme position, but the biasing device 35 will function as a toggle and will reverse its eifort after the star block has been rotated approximately halfway to its counterclockwise extreme position. The parts are further so proportioned that the total force exerted on the star block tending to restore it to its normal position will decrease as the star block is rotated away from this position, but that the force tending to return the star block to its normal position when the star block has been rotated from the position shown to either extreme position will always be The end plate 39 is screwed greater than the force tending to oppose this movement to its normal position. It follows, therefore, that, when the star block has been rotatedi-away from the position shown in either direction, as soon as the force which caused the rotation of the star block is removed, the biasing devices will act to restore the star block to the position shown.

Reciprocably mounted in the bottom of the casing H is a locking device 60 which,.as here shown, comprises two spaced cross members 60a and 60b connected together by means of a pair of spaced stud bolts 60c and 60d. The member 60a is provided with an integral rectangular locking plunger 609 while the member 60b is provided with a centrally located hole 50k. The locking plunger 60. 7 is slidably mounted in suitable guideways not shown and is adapted to cooperate with a lock rod L which is slidably mounted in the right-hand end of the casing II at right angles to the locking plunger. The lock rod L is of standard construction and comprises two longitudinally

adjustable bars

63 and 64 attached at one end to the front rod 5 of the switch A and provided with two registering notches 65 so disposed that these notches will align with the locking plunger 609 when and only when the switch occupies its normal extreme position in which it is shown in the drawings.

The locking device 6! is arranged to be moved in a manner which will be described hereinafter between a righ -hand extreme position in which the locking plunger enters the notches 65 in the lock rod L, and a left-hand extreme position in which the locking plunger is withdrawn from the notches 65, and it will be apparent that, when the locking device is moved to the position in which the locking plunger is within the notches' 65, the switch will be positively locked in its normal extreme position, but that, when the locking device is moved to the position in which the locking plunger 609 is withdrawn from the notches 65 in the lock rod, the switch will then be unlocked.

The bolt members 600 and 66d of the locking device 60 are slidably mounted intermediate their ends in suitable lugs 65 and 61, respectively, which project upwardly from the bottom of the casing I, and surrounding each bolt between the cross member 523a and the associated lug 66 or 61 is .a partly compressed coil spring 68 which con stantly biases the locking device 60 to its righthand extreme or locking position.

A bell crank lever 69 is pivoted on a pin 16 mounted in a boss H formed on the side of the casing l l and one arm 59a thereof extends down wardly and cooperates at its lower end with a lateral extension 58h provided on the cross member 63a, in a manner which will be described hereinafter. The other arm of the bell crank lever is pivotally connected at its free end with the lower end of a vertical connecting rod 14.

The connecting rod l4 extends upwardly with a sliding fit through a guideway 15 formed in the top wall of the casing ll and is provided at its upper end with a lateral extension Mb which overlies and cooperates with an annular flange H formed on the sliding sleeve 22 directlj above the squared portion 23. A two-piece collar 18 is bolted to the sliding sleeve 22 some distance above the annular flange l1 and the lateral extension 14b, and extending downwardly from this collar is an integral frusto conical head 19 which completely encloses the upper part of the offset portion 14b of the connecting rod M and the annular flange 11, thus protecting these parts from dirt, moisture, etc.

The connecting rod 14 is also provided with another offset portion 74a which is disposed within the casing II, and which overlies and cooperates witha cam member 86 formed integrally with the star block IS. The cam member has a semicircular periphery, and its upper surface curves downwardly from each end toward the center, as shown in Fig. 2. Only one half of the cam member is visible in Fig. 2 because the other half is directly back of the half shown, but the half which is not visible is similar to the half which is visible.

The parts are so proportioned that, when the sliding sleeve 22 occupies its lowermost position, and the star block l9 occupies the position to which it is biased by the biasing

devices

35 and 35, as shown in the drawings, the connecting rod M will move by gravity to the position in which it is shown in the drawings, which position I shall hereinafter refer to as its lowermost position. The parts are further so proportioned that, when the connecting rod 14 occupies its lowermost position, the underside of the lateral extension 141) of the connecting rod will engage the upper side of the annular flange H, the offset portion 14a, will engage the upper face of the cam member 88 at the lowest point of the cam face, and the bell crank lever 69 will be rotated to a position in which the arm 69a is just clear of the offset portion 6071 of the loclc ng device 60.

The locking device 60, in addition to being operatively connected with the sliding sleeve 22 and the star block [9 in the manner just described, is also operatively connected with the tie rod 8 by means of linkage which I shall now describe.

As here shown, this linkage includes a plunger bolt 8| (see Figs. 1 and 3) which extends with some clearance through the hole 60k in the cross member 561) of the locking device 60, and the head of which bolt cooperates with the righthand side of the cross member 601). The threaded left-hand end of the plunger bolt 8! is adjustably connected by means of a turnbuckle 82 with one end of a link 83, the other end of which link is pivotally connected with the long arm 84a, of the bell crank lever 84. The bell crank lever 84 is pivotally supported in a crank stand 85, and has its short arm 54b pivotally connected with one end of an operating rod 86. The other end of the operating rod 86 is connected with the previously described tie rod 8 by means of a standard switch basket 81.

The tie rod 8 may be located at any suitable location, but will preferably be located approximately midway between the heel and the point of the switch. The crank stand is secured both to a gauge plate 89 and to a bed plate l5, which latter plate is also secured to the casing of the mechanism B. It will be apparent, therefore, that any loss of adjustment between the parts due to creepage of the ties is prevented. The linkage is so adjusted that, when the switch occupies its normal extreme position, the head of the plunger bolt 8| will engage the end member 68b when the locking plunger occupies its locking position within the notches 65 in the lock rod L.

If desired, a suitable circuit controller may be provided in the right-hand end of the casing to indicate when the locking plunger occupies its proper locking position and the switch points occupy their proper positions with respect to the stock rails. This circuit controller forms no part of my present invention, andit is not, therefore,

shown in the drawings. This circuit controller may, however, be similar to that shown and described in Letters Patent of the United States No. 1,989,128, granted to me on January 29, 1935, for Railway switch circuit controllers.

The apparatus also includes a biasing device U which in the form here shown comprises a cylinder 9i containing a reciprocable piston 92 attached to one end of a piston rod 93. The cylinder Si is pivotally connected with the one arm 54a of a link 94 which is pivotally mounted intermediate its ends on an upstanding pin 95 secured to the base of the casing ll, while the piston rod 93 is pivotally connected at its free end with the star block l9 by means of the pin 55. The arm 94b of the crank 94 is pivotally connected with one end of a link 96 the other end of which is pivotally connected with the long arm Ella of a bell crank lever 91. The bell crank lever 97 is pivotally supported on an upstanding pin 98 se cured to the base of the casing II, and the short arm 91b thereof carries a roller 99 which cooperates with a cam I80 provided on the star block. The parts are so proportioned that, when the star block occupies the position to which it is biased by the biasing

devices

35 and 36, the piston 92 will occupy a projected position in which it is shown in the drawings, but that, when the star block is rotated away from the extreme position shown in either direction through a distance corresponding to the switch stroke, the rotation of the start block will act through the pin and through the crank 91, link 95, and crank 94 to move the piston and cylinder relative to each other in such manner that the piston will be moved to its retracted position in the cylinder during approximately three-quarters of the stroke of the star block and will then be moved partway toward its projected position during the balance of the stroke.

Mounted in the left-hand end of the cylinder SI of the biasing device U is a magnet valve V of the usual and well-known construction. The valve V controls communication between the cylinder SI and the atmosphere in such manner that, when the valve is deenergized, the cylinder will be connected with atmosphere, but that, when the valve V is energized, the cylinder will be disconnected from atmosphere. The winding of the valve V is connected with the rails and la in series with a battery B by means of a pair of wires I01 and I02 whereby this winding will become energized whenever a train moves over the switch A.

The operation of the apparatus as a whole is as follows: As shown in the drawings, the movable rails of the switch are in their normal extreme positions, and the hand lever 27 is locked in its depending position by means of the padlock 3|. Under these conditions, the sliding sleeve 22 is held in its lowermost position on the inner sleeve 2!, and the star block [9 is accordingly connected with the switch actuating shaft I6 so that the

biasing devices

35 and 36 are effective to hold the movable rails of the switch in their normal positions. Furthermore, under these conditions, the magnet valve V is deenergized, the piston 92 of biasing device U occupies its projected position in the cylinder 9|, the connecting rod M is held by gravity in its lowermost position, and the locking device is held in its locking position by the biasing springs 68. As was previously pointed out, when the locking device 60 occupies its locking position, the movable rails of the switch are locked in their normal positions, thus rendering the switch safe for high speed traffic over the switch in a facing point direction.

I shall now assume that it is desired to reverse the switch A. To do this, the padlock 31 is first removed from the hole 32a in the lug 32 to unlock the hand lever 27, and the hand lever 21 is then raised to its horizontal position. This preliminary movement of the hand lever raises the sliding sleeve 22 from its lowermost position in which it is shown in the drawings to its uppermost position, and as was previously pointed out, when the sliding sleeve is moved to its uppermost position, the squared portion 23 on the lower end of this sleeve becomes disengaged from the socket 24 in the upper end of the star block [9, thus disconnecting the star block, and hence the

biasing devices

35 and 35 and the biasing device U from the switch actuating shaft, so that the switch actuating shaft is then free to rotate without any opposition from the biasing devices. Furthermore, when the sliding sleeve 22 is moved to its upper position, the annular flange 1'! on the lower end of this sleeve cooperates with the lateral ex tension 14b on the connecting rod 14, to move the connecting rod 14 to its uppermost position, and this movement of the connecting rod, in turn, acts through the bell crank lever 69 to move the locking device 60 from its normal locking position in which it is shown in the drawings to a position in which the locking plunger 60g is completely withdrawn from the notches in the lock rod L, hus unlocking the switch. The biasing devices and the fluid pressure motor now being disconnected from the switch actuating shaft, and the switch being unlocked, the hand lever 21 is next rotated in a horizontal plane which it then occupies, through an angle of approximately 90 in a counterclockwise direction. This intermediate movement of the hand lever rotates the switch actuating shaft I6 to the extreme position opposite to that in which it is shown in the drawings, thereby reversing the movable rails of the switch in the manner previously described. As the movable rails move to their reverse positions, the linkage which connects the locking device 69 with the tie rod 8 is actuated in such manner that the plungenbolt 8| is moved toward the left, and as soon as the plunger bolt has moved as far as the locking device 60 was previously moved by the bell crank lever 69, the head of the plunger bolt engages the end member 602) of the locking device 60, and during the balance of the movement of the plunger bolt, the locking device will be moved with the plunger bolt, so that, when the switch reaches its full reverse position, the locking device will be moved to its extreme left-hand position. The switch points now being fully reversed, the hand lever 21 is next restored to its depending position. This final movement of the hand lever, of course, restores the sliding sleeve 22 to its lowermost position, thus reconnecting the star block IS with the switch actuating shaft [6, and at the same time permitting the connecting rod 74 to return by gravity to its lowermost position. After the hand lever has been restored to its depending position it may, if desired, be relocked in this position by again inserting the padlock 3| in the hole 32a of the lug 32.

If, when the switch has been moved to its reverse position in the manner just described, it is desired to restore the switch to its normal position, the hand lever 2'! is first raised to its horizontal position, and is then rotated in a clockwise direction through an angle of 90, as

viewed in Fig. 1, and is finally restored to its depending position and relocked in this position. The operation of the various parts of the apparatus under these conditions is just the reverse of that described above and Will be readily understood from the foregoing description and from an inspection of the drawings without further detailed description.

I shall now assume that the parts are in their normal positions in which they are shown in the drawings, and that a train trails the switch. Under these conditions, as the leading wheels of the train roll along the fixed rail I and the movable rail 20., the

movable rails

2 and 2a will be forced over laterally, but before a sui'licient force is developed at the points of these rails to overcome the opposing force of the

biasing devices

35 and 36 and cause the point of the movable rail 2 to tend to move out of engagement with the fixed rail l, the movable rails, being somewhat resilient, become bent, so that with the usual standard split switch, the tie rod 8 will be moved upwardly, as viewed in Fig. 1, threequarters of an inch or more. This movement of the tie rod 8 acting through the switch basket 8?, operating rod 86, bell crank lever 84, link 83, and plunger bolt 8i moves the locking device 60, in opposition to the bias of the springs 68, a sufficient amount to completely withdraw the locking plunger 63g from engagement with the notches 65 in the lock rod L, thus unlocking the switch. As a result, when the leading wheels of the train have reached the position in which a sufiicient force is developed at the points of the movable rails to cause the point of the movable rail 2 to move out of engagement with the fixed rail l, the movable rails will be unlocked, and these rails will therefore be forced away from their normal positions by the wheels of the train in exactly the same manner as they would be if no point lock were provided. The movement of the movable rails away from their normal positions acts through the operating rod 9 and crank H to rotate the shaft IS in a counterclockwise direction, as viewed in Fig. 3, and this rotation of the shaft It, in turn, rotates the associated sleeves 2i and 22 and hence the star block iii in the same direction. The rotation of the star block l9 actuates the biasing devices 35 and 3G in the manner previously described so that these biasing devices now tend to constantly return the movable rails to their normal positions with a force which decreases with the displacement of the movable rails, as will be apparent from an examination of the curve I05 shown in Fig. 4. The rotation of the star block [9 also moves the cylinder 9! and piston 92 of the biasing device U relative to each other in the manner previously described, and since valve V is now energized, fluid will become compressed in the cylinder 9!! during approximately 80 per cent of the stroke of the switch and will then expand during the balance of the stroke, thus causing a force to be exerted on the star block which tends to complete the movement of the switch points to their full reverse positions. The force which is exerted on the switch points due to the cam reaction is illustrated graphically by the curve ")6 in Fig. a, while the force which is exerted on the switch due to the compressed fluid in the biasing device is illustrated by the curve I81, and the resultant force which is exerted on the switch is illustrated by the curve I08. It will be apparent from an examination of these curves that, when the switch points are within a short distance of their reverse positions, the force which is exerted on the switch points by the biasing device tending to move them to their reverse positions exceeds that which is exerted on the switch points by the two spring units, and it follows that the biasing device U will therefore become effective to force the switch points to and hold them in their full reverse positions. After the train has completely passed the switch, it will move ofi of the track circuit in which the magnet valve V is included and will thus cause this magnet valve to become deenergized. When this happens, the fluid which was previously trapped in the cylinder 9| will become exhausted to atmosphere, and will thus remove the force which was previously exerted on the points by the biasing device U, whereupon the

spring units

35 and 36 will then become eiTective to return the switch points to their normal positions. As soon as the points have moved toward their normal positions approximately half of their stroke, spring unit 35 will then exert a force on the points which aids that exerted on the points by the spring unit 36 and it will be apparent, therefore, that the remainder of the movement of the points to their normal positions will be relatively rapid. When the switch points have been restored to their full normal positions, all parts will then be restored to their normal positions in which they are shown in the drawings.

It should be pointed out that, with the apparatus constructed in the manner just described due to the fact that the force which is exerted on the switch points by the two

spring units

35 and 36 gradually decreases as the points are moved away from their normal positions to their reverse positions by a trailing train, the force which must be exerted on the points to compress the fluid in the cylinder, 9| when a train is trailing the switch will not be materially greater than that which must be exerted on the points of spring switches of the usual and well-known type.

The means for unlocking the switch as shown in'Fig. l is arranged so that it will only function when the switch occupies its normal position and a train trails the switch. However, this means may be arranged in the manner shown in Letters Patent of the United States No. 1,992,551, granted to W. L. Stout, on February 26, 1935, for Railway switch operating apparatus, and when the means for unlocking the switch is arranged in this manner if the switch is then moved to its reverse position by the switch operating mechanism and a train trails the. switch, the apparatus will then function in a manner which is similar to that just described, and which will be apparent from the foregoing description without further detailed description.

It should also be pointed out that, with the apparatus constructed in the manner described, the biasing device U takes the place of the usual bufiing device so that the total equipment requirement is no greater than that employed in spring switches of the type now in use.

It should further be pointed out that, with the apparatus constructed in the manner described, since the switch points are forced to their full reverse positions while a train is trailing the switch, the wear on the points is materially reduced.

Referring now to the modified form of apparatus illustrated in Fig. 6, as here shown, the

spring units

35 and 36 and the biasing device U shown in Figs. 2 and 3 have been replaced by two biasing devices UI and U2 which also embody my invention. These biasing devices are similar, and a clear understanding of both will therefore be had from a description of only one. Referring particularly to the device UI shown in section in Fig. '1, this device comprises two air cylinders H0 and III secured to the opposite ends of a cylindrical spring housing II 2. A piston rod H3 extends into the cylinders H0, the housing H2, and the cylinder III through a stumng box H4 provided in a cylinder head H5 which closes the outer end of the cylinder II 0, and secured to this piston rod within the cylinder H0 is a reciprocable piston H6. A reciprocable piston H1 is also mounted in the cylinder III, and this piston cooperates at its right-hand side with an upset end H8 formed on the piston rod H3, in a manner which will be explained more fully hereinafter. The piston I I1 is guided by a suitable guide rod H9 secured to the lefthand end wall of the cylinder. Surrounding the piston rod I I3 within the housing H2 are three compressed coil springs I20, I2I, and I22. One end of these springs abuts against a member I23 which is slidably mounted in the housing II 2, and the other end of these springs abuts against a similar memberIZ l which is likewise slidably mounted in the housing H2. The two members I23 and I24 are each provided with a centrally located hole I25 which receives the piston rod H3 with some clearance, and cooperate respectively with the piston I I6 and with the upset end H8 of the piston rod H3. The members I23 and I24 also cooperate with annular shoulders I26 and I21 formed at the junction of the cylinder H0 and the housing I I2, and the junction of the cylinder III and the housing H2, respectively, the parts being so proportioned that, when the members are engaging the shoulders I26 and I21, the member I23 will just clear the piston II 6, and the member I24 will be just clear of the upset end H8 of the piston rod. It will be apparent, therefore, that the springs I20, I2I, and I22 all act to bias the piston rod I I3 to the position shown, and that movement of the piston rod in either direction from this position will act to compress these springs beyond their initial compression. The parts are further so proportioned that, when the piston rod occupies the position shown, the piston H1 will be free to move to either end of its stroke, and the piston II 6 will be located in such a position that the piston rod H3 can be moved into the device U far enough to cause the upset end H8 of the piston rod to engage the piston H1 and force it from its right-hand or projected position to its left-hand or retracted position.

The cylinder III is provided with a port I21 through which fluid may be at times admitted to the cylinder to move the piston to its projected position, and mounted on this cylinder is a magnet valve V which connects the cylinder with, or disconnects it from atmosphere according as the valve V is deenergized or energized.

The biasing device UI also comprises two valves VI and V2 which are mounted in the cylinder head H5, and which are actuated by engagement with the piston I I 6. The valve VI is of the piston type and comprises a piston I30 secured to a stem I3I, and biased to the lefthand end of a cylinder I32 in which the piston I30 reciprocates. When the piston occupies the position shown, the cylinder H0 is connected with a pipe I33 which is screwed into the outer end of the valve through a plurality of radially disposed ports I34. formed in the side wall of the.

cylinder I32, but when the piston I30 is moved toward the right, it moves past the ports I34 and disconnects the cylinder I I0 from the pipe I33.

The valve V2 is of the poppet type and comprises a valve member I35 secured to a fluted valve stem I36, and biased by means of a spring I31 to a position in which the member I 35 engages a valve seat I38. When the member I35 is unseated, the cylinder H0 is connected with atmosphere through a port I39, but, when the valve is seated, the cylinder H0 is then disconnected from atmosphere. The spring I31 is made stiff enough so that any air pressure which is developed in cylinder I I 0 will not open the valve. The valve stem I36 is made somewhat shorter than the valve stem I 3| so that, when the piston I I6 is moved to its right-hand extreme position, it will engage the stem I3I and close the valve VI before it opens the valve V2.

The devices UI and U2 are pivotally attached, at the ends opposite to the piston rods, to the casing I 44 by means of pins I40, and the piston rods of these devices are both pivotally attached to the star block I9 by means of the pin 55. The pipe I33 of the device UI is connected to the cylinder III of the device U2 at the associated port I21, and the pipe I33 of the device U2 is connected with the cylinder III of the device III at the associated port I21.

The windings of the magnet valves V are connected in parallel and are connected with the wires lol and I02 so that the valves V will become energized whenever a train trails the switch.

The remainder of the apparatus shown in Fig. 6 is similar to that shown in Fig. 1 and will be understood from the foregoing description of Fig. 1 without further detailed description.

The operation of the apparatus shown in Fig. 6 when the switch is moved between its two extreme positions by means of the hand lever 21 is identical with that previously described in connection with Fig. 1, and this operation will therefore be understood from the foregoing description without further detailed description.

When the switch occupies its normal position and a train trails the switch, the operation of the apparatus will be similar to that shown in Fig. 1 when the switch occupies its normal position and a train trails the switch with the following exceptions. Under these conditions, the counterclockwise rotation of the star block which takes place after the switch points become unlocked in response to the movement of the points away from their normal positions by the trailing train will cause the piston rod H3 of the device U2 to move out of the device, and will cause the piston rod H3 of the device UI to first move into the device until after the switch has moved to its mid stroke position whereupon this latter piston rod will again then start out of the device UI. The movement of the piston rod II 3 of the device U2 out of this device will cause the load exerted on the switch by the spring assembly of this device to increase while the movement of the piston rod H3 of the device UI will cause the spring assembly of the device UI to first exert a force on the switch which opposes its movement and to then exert a force on the switch which aids its movement, thus causing the total force which is exerted on the switch by the two spring assemblies to decrease as the switch points move away from their normal positions. The movement of, the piston rod H3 of the device U2 will also cause the piston H6 of this device to move with the piston rod and, since valve VI is then open and valve V2 is closed, the movement of the piston will compress fluid in the cylinder I I0 and force it through the pipe I33 into the cylinder III of the device Ul. When the fluid is forced into the cylinder HI under these conditions, the magnet valve V will be energized due to the presence of the train on the switch, and the fluid which is forced into the cylinder III will therefore build up a pressure behind the piston l l! and will thus cause the piston II! to move into engagement with the piston rod H3 and exert a force on this piston rod which aids that due to the spring assembly in urging the switch points to their full trailed positions. Fluid will continue to be compressed in the cylinder l I 6 of the device U2 and to be forced into the cylinder III of the device Ul until the switch points have been moved approximately per cent of their stroke at which time the piston H6 of the device U2 will close valve VI of this device and open the valve V2. This retains the pressure in the cylinder H! of the device UI and releases it from the cylinder N0 of the device U2. The forces exerted on the switch points by the various parts of the devices U! and U2 during the movement of the points is illustrated graphically in Fig. 8, and it will be apparent from an inspection of this figure that, when the switch points have moved approximately four-fifths of their stroke, the combined force due to the fluid in the cylinder I ll of the device U! and the spring assembly of this device will exceed the opposing force due to the spring assembly of the device U2 with the result that the switch points will be forced to their full trailed positions by the device Ul. The valve V will remain energized until after the train has completely passed the switch, and it follows, therefore, that the switch points will be held in their full reverse positions until the train has completely passed the switch and deenergized the valve V. When this happens, the fluid which was previously trapped in the cylinder Ill of the device UI will be allowed to escape to atmosphere, whereupon the force which is exerted on the switch points by the device Ul will become less than that exerted on the switch points by the device U2, and the device U2 will therefore start to return the switch points to their normal positions. As soon as the switch points have been returned approximately halfway toward their normal positions, the device U! will then become effective to assist the device U2 in completing the movement of the switch points and it follows, therefore, that the points will return rapidly to their normal positions. As soon as the switch points have been returned to their normal positions, all parts will then be returned to the positions in which they are shown in the drawings.

If the switch is movedto its reverse position by means of the hand lever and a train trails the switch, the switch will, of course, be unlocked so that the locking mechanism will not function, but the devices UI and U2 will be effective to force the switch points to their full normal positions and retain them there until after the train has passed the switch in a manner which will be readily understood from the foregoing description it being noted that, under these conditions, the device U2 will function as a toggle instead of the device Ul. It should also be noted that, under these conditions, when the switch points have been moved to their normal positions, the locking plunger will be prevented from entering the notches in the lock rod and locking the switch in their normal position by the cooperation between the cam 80 and the cam follower M.

It should be particularly pointed out that, while the air is retained in the air cylinders in the two forms of apparatus previously described, the mechanism would function in practically the same manner if a small orifice were provided in place of the pin valves. Under these latter conditions, the switch would remain in its full trailed position until the compressed fluid had leaked out through the restricted orifice to the point where the pressure which was exerted on the switch points by the active air cylinder was insuflicient to overcome the opposing force tending to return the points to their normal positions. The time necessary for the compressed fluid to leak out of the cylinder could be adjusted by varying the size of the orifice and by properly varying the size of the orifice the switch could be retained in its trailed position for a period of time which would be long enough to permit a train trailing the switch at the usual speeds to completely pass the switch. If the time required for a train to trail the switch exceeded that required for the compressed fluid to leak out of the active cylinder, the mechanism would, of course, release and the switch points would then have to be forced back to their trailed position by the trailing train, whereupon the switch points would again be retained in their trailed positions for another time interval.

Although I have herein shown and described only one form of 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. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, means connected with said shaft for operating said switch between its two extreme positions and for biasing said switch to a selected extreme position, and means including a fluid pressure device operatively connected with said shaft and supplied with fluid pressure by the movement of a train trailing said switch to apply to said switch a force which opposes and exceeds the force of said biasing means.

2. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, means connected with said shaft for manually operating said shaft between two extreme positions to actuate said switch between its two extreme positions and for biasing said shaft to whichever position it is operated with a force which decreases with the displacement of the switch when a train trails the switch, and a fluid pressure motor operatively connected with said shaft and supplied with fluid pressure by the movement of the switch points when a train trails said switch for applying to said switch a force which opposes and exceeds the force of said biasing means.

3. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft, means at times connected with said shaft for biasing said shaft to a selected extreme position with a force which decreases with the displacement of the switch when a train trails the switch, a fluid pressure device provided with a valve which becomes closed when a train trails the switch, and means connecting said device with said shaft in such manner that the resultant movement of said shaft when a train trails the switch and said valve is closed will cause fluid to become compressed in said device during a portion of the switch stroke toward its trailed position and allow it to expand during the balance of the switch stroke to apply to said switch a force which in the trailed position of the switch opposes that due to said biasing means.

4. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft, means at times connected with said shaft for biasing said shaft to a selected extreme position with a force which decreases with the displacement of the switch when a trail trails the switch, a fluid pressure device provided with a valve which becomes closed when a train trails the switch, and means connecting said device with said shaft in such manner that the resultant movement of said shaft when a train trails the switch will cause fluid to become compressed in said device during a portion of the switch stroke toward its trailed position and allow it to expand during the balance of the switch stroke to apply to said switch a force which in the trailed position of the switch opposes and exceeds that due to said biasing means.

5. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft, means at times connected with said shaft for biasing said shaft to a selected extreme position with a force which decreases with the displacement of the switch when a train trails the switch, a fluid pressure device provided with a valve which becomes closed when a train trails the switch, and means connecting said device with said shaft in such manner that the resultant movement of said shaft when a train trails the switch will cause fluid to become compressed in said device during a portion of the switch stroke toward its trailed position and allow it to expand during the balance of the switch stroke to apply to said switch a force which urges the switch points to and holds them in their trailed positions until after the trailing train has passed the switch.

6. In combination, a railway switch, a switch actuating shaft operatively connected with said switch, a star block journaled on said shaft, manually operable means for rotating said shaft between two extreme positions corresponding to the extreme positions of saidswitch and for connecting said star block with said shaft in either extreme position to which it is rotated, means for biasing said star block to one position in such manner that the biasing force will decrease as it is rotated away from said one position, a fluid pressure motor provided in one end with a valve which becomes closed when a train trails the switch, and means for operatively connecting said motor with said star block in such manner that when said star block is connected with said shaft and a train trails the switch fluid will become compressed in said motor during a portion of the switch stroke and will expand during the remainder of the stroke to exert a force on the star block which opposes that due to said biasing devices.

7. In combination, a railway switch, a switch actuating shaft operatively connected with said switch, a star block journaled on said shaft, manually operable means for rotating said shaft between two extreme positions corresponding to the extreme positions of said switch and for connecting said star block with said shaft in either extreme position to which it is rotated, means for biasing said star block to one position in such manner that the biasing force will decrease as it is rotated away from said one position, a fluid pressure motor provided in one end with a valve which becomes closed when a train trails the switch, and means for operatively connecting said motor with said star block in such manner that when said star block is connected With said shaft and a train trails the switch fluid will become compressed in said motor during a portion of the switch stroke and will expand during the remainder of the stroke to exert a force on the star block which opposes and exceeds that due to said biasing devices.

8. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, means operatively connected with said shaft for moving said switch between its two extreme positions and for biasing said switch to whichever extreme position it is moved, an air cylinder, means for connecting said cylinder with said shaft in such manner that the piston of said cylinder will move from a projected position to a retracted position and partway back to its projected position when a train trails the switch, a magnet valve connected with the end of said cylinder toward which said piston moves when it moves toward its retracted position and effective when energized for disconnecting said cylinder from atmosphere, and means for energizing said magnet valve when a train trails the switch.

9. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, means operatively connected with said shaft for moving said switch between its two extreme positions and for biasing said switch to whichever extreme position it is moved, an air cylinder, means for connecting said cylinder with said shaft in such manner that the piston of said cylinder will move from a projected position to a retracted position and partway back to its projected position when a train trails the switch, a magnet valve connected with the end of said cylinder toward which said piston moves when it moves toward its retracted position and effective when energized for disconnecting said cylinder from atmosphere, and means for energizing said magnet valve when a train trails the switch, the parts being so proportioned that the fluid which becomes compressed in said cylinder when a train trails the switch will force the switch points to their trailed positions and hold them there until said magnet valve becomes deenergized.

10. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, a rotatable star block, manually operable means for rotating said shaft between two extreme positions corresponding to the extreme positions of said switch and for connecting said star block with said shaft in either extreme position of the shaft, means connected with said star block for biasing said star block to one position in such manner that the biasing force will decrease when said star block is moved away from said one extreme position, and other means connected with said star block and effective while a train is trailing the switch for exerting on said star block a force which opposes and exceeds the force of said biasing means,

11. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, a rotatable star block, manually operable means for rotating said shaft between two extreme positions corresponding to the extreme positions of said switch and for connecting said star block with said shaft in either extreme position of the shaft, means connected with said star block for biasing said star block to one position in such manner that the biasing force will decrease when said star block is moved away from said one position, a fluid pressure cylinder containing a reciprocable piston attached to a piston rod, means for operatively connecting said cylinder and said piston rod with said star block in such manner that the piston of said cylinder will move from a projected position to a retracted position and partway back to its projected position when a train trails the switch, a magnet valve connected with the end of said cylinder toward which said piston moves when it moves toward its retracted position and effective when energized for disconnecting said cylinder from atmosphere, and means for energizing said magnet valve when a train trails the switch.

12. In combination, a railway switch of the type adapted to be trailed, a switch actuating s -aft operatively connected with said switch, means connected with said shaft for operating said switch between its two extreme positions and for normally biasing said switch to a selected extreme position, means including a fluid pressure device operatively connected with said shaft supplied with fluid pressure by the movement of said shaft when a train trails the switch to apply to said switch a force which opposes and exceeds the force of said biasing means.

13. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, means connected with said shaft for biasing said switch to one extreme position in such manner that when said switch is moved away from said one extreme position by a trailing train the biasing force will decrease, and fluid pressure means connected with said shaft and supplied with fluid pressure by a train trailing said switch from said one position for applying to said shaft a force which opposes that due to said biasing means.

14. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, means connected with said shaft for biasing said switch to one extreme position in such manner that when said switch is moved away from said one extreme position by a trailing train the bias ing force will decrease, and fluid pressure means connected with said shaft and supplied with fluid pressure by a train trailing said switch from said one position for applying to said shaft a force which opposes that due to said biasing means, and which is sufficient to force said switch to and hold it in its other extreme position until after the trailing train has passed said switch.

' 15. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, means connected with said shaft for biasing said switch to one extreme position, and fluid pressure means connected with said shaft and supplied with fluid pressure by a train trailing said switch from said one position for applying to said shaft a force which opposes that due to said biasing means.

16. In combination, a railway switch of the type adapted to be trailed, a switch actuating shaft operatively connected with said switch, means connected with said shaft for biasing said switch to one extreme position, and fluid pressure means connected with said shaft and supplied with fluid pressure by a train trailing said switch from said one position for applying to said shaft a force which opposes that due to said biasing means and is sufficient to force said switch tn and hold it in its other extreme position until after the trailing train has passed said switch.

17. In combination, a railway switch of the type adapted to be trailed, a rotatable switch actuating shaft, means operatively connecting said shaft with said switch, biasing means con nected with said shaft and effective for biasing said switch to a selected extreme position, a first fluid pressure device operatively connected with said shaft and effective when said switch is trailed from its selected extreme position and said de vice is supplied, with fluid pressure for exerting a force on said shaft which opposes and exceeds the force of said biasing means, a second fluid pressure device, means for operatively connecting said second device with said shaft in such manner that when said switch is trailed from its second extreme position fluid will become compressed in said second device, and means for supplying the fluid compressed in said second device to said first device.

18. In combination, a railway switch of the type adapted to be trailed, a casing containing a rotatable switch actuating shaft, means operatively connecting said shaft with said switch, biasing means connected with said shaft and effective for biasing said switch toa selected extreme position, two fluid pressure devices operatively connected with said shaft and with each other in such manner that when a train trails said switch from said selected extreme position fluid will become compressed in the one device and will be supplied to the other device to cause a force to be exerted on said shaft which opposes and exceeds the force of said biasing means, and means effective after a train has trailed said switch for venting the fluid supplied to said other device to atmosphere.

19. In combination, a railway switch of the type adapted to be trailed, a casing containing a rotatable switch actuating shaft, means operatively connecting said shaft with said switch, a star block journaled in said casing, manually operable means for rotating said shaft between two extreme positions corresponding to the two extreme positions of a railway switch and for connecting said star block with said shaft in either extreme position of said shaft, two biasing devices each including two air cylinders secured to the opposite ends of a cylindrical housing, a piston rod extending into the two cylinders and the housing of each device, a piston secured to each piston rod within one of the associated cylinders, a piston reciprocably mounted in each of the other cylinders of each device and cooperating with the inner end of the associated piston rod, a normally closed and a normally open valve in the end of said one cylinder of each device toward which the associated piston moves when the piston rod is moved out of the cylinder operated by the piston when the piston is moved to one end of its stroke in such manner that the normally open valve will close before the normally closed valve opens and effective respectively for controlling communication between the associated cylinder and atmosphere and the associated cylinder and said other cylinder of the other biasing device on the side opposite the piston rod, means in the housing of each device for biasing the piston rod to one position, means for pivotally connecting the piston rod of each device with said star block and the opposite end with said casing in such manner that the star block is biased by both devices to one position but that when the star block is rotated away from said one position through an angle corresponding to the switch stroke in one direction the piston rod of the one device will be moved out of the device and the other piston rod of the other device will first be moved into the device and then out and that when the star block is rotated away from said one position through an angle corresponding to the switch stroke in the opposite direction the piston rod of the other device will be moved out of the device and the piston rod of the one device will first be moved into the device and then out, whereby when a train trails the switch the biasing force exerted on the switch due to the biasing means of each device will decrease, a magnet valve connected with said other cylinder of each device on the side opposite the piston and effective when energized for disconnecting the associated cylinder from atmosphere, and means for energizing said valves whenever a train trails the switch.

HERBERT L. BONE.