US2224413A - Railway switch operating apparatus - Google Patents
Railway switch operating apparatus Download PDFInfo
- Publication number
- US2224413A US2224413A US284033A US28403339A US2224413A US 2224413 A US2224413 A US 2224413A US 284033 A US284033 A US 284033A US 28403339 A US28403339 A US 28403339A US 2224413 A US2224413 A US 2224413A
- Authority
- US
- United States
- Prior art keywords
- lever
- shaft
- pawl
- switch
- lug
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L5/00—Local operating mechanisms for points or track-mounted scotch-blocks; Visible or audible signals; Local operating mechanisms for visible or audible signals
- B61L5/02—Mechanical devices for operating points or scotch-blocks, e.g. local manual control
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L5/00—Local operating mechanisms for points or track-mounted scotch-blocks; Visible or audible signals; Local operating mechanisms for visible or audible signals
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T74/00—Machine element or mechanism
- Y10T74/20—Control lever and linkage systems
- Y10T74/20396—Hand operated
Definitions
- My invention relates to railway switch operat ing apparatus, and particularly to apparatus of the type whichincludes a hand lever for throwing a spring switch.
- one object of my invention is to provide means for preventing this from happening to guard against possible injury to the operator.
- Fig. 1 is a diagrammatic view showing a spring switch A operated by a switch operating mechanism B to which my invention is applicable.
- Fig. 2 is a top plan view showing mechanism embodying my invention for connecting the lever 39 with the shaft .3! of the mechanism shown in Fig. 1.
- Fig. 3 is a :s'oQfront elevational View partly in section of the mechanism shown in Fig. 2.
- Fig. 4 is a side view partly in elevation and partly in section of the mechanism shown in Figs. 2 and 3.
- Fig. 5 is a fragmentary view showing a portion of the mech- 3'5 anism illustrated in the preceding views in the positions which they occupy during one part of the stroke of the lever 38 from its normal position to its reverse position.
- Fig. 6 is a View similar to Fig. 3 but showing the parts in the opposite 'extreme positions from that in which they are shown in Fig. 3.
- the reference character A designates a railway switch comprising, as usual, two fixed rails l and la and two movable rails 2 and 2a.
- the movable rails are fastened together by a front rod 5, a head rod 6 and a tie rod 8, and may be moved into a normal or a reverse position by means of a switch operating mechanism B which is connected with the head rod 6 through the medium of an operating rod 9 and a spring connecting red C.
- the switch occupies its normal position'in which it is shown in Fig.1
- the movablerail 2 engages the fixed rail I and-the movable rail 2a is spaced a slightdistance from the fixed rail Ia.
- the switch is reversed, however, the movable rail 2a then engages the fixed rail la, and the movable rail 2 is V spaced from the fixed rail I.
- the spring connecting rod C may have any ale-- sired construction which will cause the switch points to be held inwhichever extreme position they are moved to by the mechanism B with'suf ficient' force to permit facing point moves over the switch without danger of displacement of the points, but which will yield when a train trails the switch, and thereby allowthe train to force the switch points to positions opposite to their initially set positions.
- One form of spring con 1% necting rod which will accomplish the necessary results is shown and described in Letters Patent of the United States No. 1,976,827, granted to Herbert L. Bone, on October 16, 1934, for Railway switch operating apparatus.
- the switch operating mechanism B may, for example, besimilar to that shown and described in the said Bone Patent No. 1,976,827 just referred to, and the various parts are designated in thedrawings by the same reference characters as 2B they are designated by in the patent. It is believed, therefore, that for purposesof my present invention the following brief description of this mechanism will suffice.
- the mechanism B includes a motion plate 26 whichis arranged to be reciprocated betweentwo extreme positions by means of a hand lever :30 through the medium of a shaft 3
- acami slot 23 Formed in the motion plate is acami slot 23 provided with offset end portions which ex- 35 tend parallel to the direction of motion of the motion plate, and with an intermediate connecting" portion which extends at an angle to the direction of motion of the motion plate,and this slot coopa crates with a roller 34 operatively co-nnected with 4 the operating rod 9 in such manner that the switch, will be moved to its normal or to'its ref verse position according as the motionplate occupies the extreme position shown, or its opposite extreme position.
- the mechanism also includes a locking plunger iite which cooperates with a pair of aligned notches 48 in a lock rod L secured to the front rod 5 of the switch A.
- the locking plunger is biased by means of a spring 391i to a locking position in which, when the switch occu 5 pies its normal position, it will enter the notches 48 in the lock rod Land thus'lock the switch in its normal position, but thelocking plunger is arranged to be moved to an unlocking position,- prior to any movement of the switch points away 5 from their normal positions by the mechanism B, by suitable means indicated diagrammatically in the drawings by a lug 42 provided on the motion plate and cooperating with a lug 39d provided on the locking plunger.
- the locking plunger is also arranged to be moved to its unlocking position, prior to any movement of the switch points away from their normal positions by a trailing train, through the medium of suitable lock releasing linkage including a'bell crank lever 51, substantially as described in the said Bone Patent No. 1,976,827 referred to above.
- the lever 30 is formed with a hub 300. having an integral flange 30b provided with a lug 30c, and with a stud 30d carrying a pawl 30c.
- the hub 30a of the lever is journaled on the outer end of the shaft 3
- also cooperates with the pawl 36c, and is provided in one side with a notch 6 la, which, when the parts are in their normal positions in which they are shown in Fig. 3,,receives the upper end ofthe pawl.
- the pawl is constantly biased to the position in which it enters the notch 6
- the pawl is arranged to be automatically disengaged from the notch in response to rotation of the lever in the direction to move the switch to its reverse position, by means of a trip arm 63, and in order to enable the pawl to be readily disengaged from the notch, the upper end of the pawl and the adjacent side of the notch are rounded in the manner shown.
- the trip arm 63 is pivoted on a pin 64 mounted in a pair of spaced lugs 65 formed on a frame 66 bolted to the side of the mechanism casing II, and is biased to a position in which a finger 61 formed on the end of the trip arm projects into the path of movement of the pawl by means of a compressed coil spring 68.
- One end of the spring 68 extends into a cup 69 formed on the trip arm, and the other end extends into a recess formed in the mechanism case.
- the righthand side of the finger 61 is beveled at 61a for a purpose which will be made clear presently.
- the pawl will swing clear of the trip finger, whereupon the spring 62 will restore the pawl to its normal position; and, when the lever 30 reaches the position corresponding to the position of the collar, the lug 300 will move back into engagement with the lug 6
- a shaft rotatable between two extreme positions and connected with means which at times tends to rotate said shaft quickly toward one extreme position
- a driving collar secured to said shaft and provided with a lug
- a manually operable lever journaled on said shaft and provided with a lug which cooperates with the lug on said collar during rotation of said lever in one direction to cause said shaft to rotate in response to rotation of said lever
- a pawl pivotally attached to said lever and biased into engagement with the lug on said collar and cooperating with the lug on said collar during rotation of the lever in the other direction to cause said shaft to rotate with said lever
- a trip arm effective to move said pawl out of operative engagement with the lug on said collar during rotation of the lever in one direction to permit said shaft to rotate independently of the lever to prevent the lever from being jerked out of an operators hands.
- a shaft rotatable between two extreme positions and connected with means which when the shaft is rotated to either extreme position exerts a yieldable force on it tending to rotate it away from such extreme position
- a driving collar fixed to the shaft and provided with a lug
- a lever journaled on the shaft and provided with a lug which when the lever is rotated in one direction cooperates with the lug on said collar to rotate said shaft to its one extreme position
- a driving collar fixed to the shaft and provided with a lug
- a lever journaled on the shaft and provided with a lug which when the lever is rotated in one direction cooperates with the lug on said collar to rotate said shaft to its one extreme position
- pawl secured to said lever and biased to a position in which it enters a notch in the lug on said collar and effective during rotation of said shaft in the other direction to rotate said shaft to its other extreme position through the medium of said collar, and a pivoted trip arm biased to a position in which it cooperates with said pawl during rotation of said lever in said one direction to rotate said pawl out of said notch to a position in which said shaft is free to rotate independently of said lever to prevent rotation of the lever by said yieldable force.
- a first member rotatable between two extreme positions
- a second member rotatable between two extreme positions
- a lug on said first member cooperating with a lug on said second member for causing said second member to rotate from one extreme position to another extreme position in response to rotation of said first member from its one extreme position to its other extreme position
- a pivoted pawl mounted on said first member, means for holding said pawl in driving engagement with the lug on said second member during rotation of said first member from its other extreme position to its one extreme position
- other means for moving said pawl out of the path of movement of the lug on said second member during at least a part of the movement of said second member in response to movement of said first member toward its other position, whereby said second member is constrained to rotate to either extreme position in response to rotation of said first member to the corresponding extreme position but is free to rotate toward its other extreme position independently of said first member in response to a. force applied thereto by means other than said first member.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Mechanisms For Operating Contacts (AREA)
Description
ea, 10, Mm w. E. SMITH 2 9 RAILWAY SWITCH OPERATING APPARATUS Filed Ju ly 12, 1959 s Shets-Sheet 1 7 INVENTOR William E mzli'h,
B a-aifiwa,
' HIS IATTORNEY Dec. 10, 1940. I w, E. SMITH 2,224,413
RAILWAY SWITGH OPERATING APPARATUS Filed July 12; 1939 '5 Sheets-Sheet 2 INVENTOR WLLLL' am 15: Smith haman HIS ATTORNEY Dec. 10, 1940. w. E. SMITH 2,224,413
RAILWAY SWITCH OPERATING APPARATUS I Filed July 12, 1939 s SheetS Sheet s 65' I 60 a 1 h. "i. 7. I Q l M. 67
INVENTOR Wilam E. Smifih 551M H ls ATTORNEY Patented Dec. 10, 1940 UNITED STATES 2,224,413 RAILWAY SWITCH OPERATING APEARATUS' Wiunm E. Smith Pittsburgh, Pa, assignor to The Union Switch &
Signal Compantn. Swissvale,
Pa., a corporation of Pennsylvania Applicatioxrliuly 12, 1939, Serial No. 234,033-
3 Claims.
My invention relates to railway switch operat ing apparatus, and particularly to apparatus of the type whichincludes a hand lever for throwing a spring switch.
In switch operating apparatus of the type described it sometimes becomes necessary or desirable to reverse the position of the switch throwing device while the switch points are held in their trailed positions by the wheels of a velo hicle which is stopped on the switch. When this happens, the releasing of the force stored in the spring biasing means tends to jerk the handthrow lever out of the operators hands, and one object of my invention is to provide means for preventing this from happening to guard against possible injury to the operator.
Other objects and characteristic features of my invention will become apparent as the description proceeds.
29" I shall describe one form of apparatus embodying my invention, and shall then point outthe novel features thereof in claims.
In the accompanying drawings, Fig. 1 is a diagrammatic view showing a spring switch A operated by a switch operating mechanism B to which my invention is applicable. Fig. 2 is a top plan view showing mechanism embodying my invention for connecting the lever 39 with the shaft .3! of the mechanism shown in Fig. 1. Fig. 3 is a :s'oQfront elevational View partly in section of the mechanism shown in Fig. 2. Fig. 4 is a side view partly in elevation and partly in section of the mechanism shown in Figs. 2 and 3. Fig. 5 is a fragmentary view showing a portion of the mech- 3'5 anism illustrated in the preceding views in the positions which they occupy during one part of the stroke of the lever 38 from its normal position to its reverse position. Fig. 6 is a View similar to Fig. 3 but showing the parts in the opposite 'extreme positions from that in which they are shown in Fig. 3.
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 l and la and two movable rails 2 and 2a. The movable rails are fastened together by a front rod 5, a head rod 6 and a tie rod 8, and may be moved into a normal or a reverse position by means of a switch operating mechanism B which is connected with the head rod 6 through the medium of an operating rod 9 and a spring connecting red C. When the switch occupies its normal position'in which it is shown in Fig.1, the movablerail 2 engages the fixed rail I and-the movable rail 2a is spaced a slightdistance from the fixed rail Ia. When the switch is reversed, however, the movable rail 2a then engages the fixed rail la, and the movable rail 2 is V spaced from the fixed rail I. 3
The spring connecting rod C may have any ale-- sired construction which will cause the switch points to be held inwhichever extreme position they are moved to by the mechanism B with'suf ficient' force to permit facing point moves over the switch without danger of displacement of the points, but which will yield when a train trails the switch, and thereby allowthe train to force the switch points to positions opposite to their initially set positions. One form of spring con 1% necting rod which will accomplish the necessary results is shown and described in Letters Patent of the United States No. 1,976,827, granted to Herbert L. Bone, on October 16, 1934, for Railway switch operating apparatus. The switch operating mechanism B may, for example, besimilar to that shown and described in the said Bone Patent No. 1,976,827 just referred to, and the various parts are designated in thedrawings by the same reference characters as 2B they are designated by in the patent. It is believed, therefore, that for purposesof my present invention the following brief description of this mechanism will suffice.
' The mechanism B includes a motion plate 26 whichis arranged to be reciprocated betweentwo extreme positions by means of a hand lever :30 through the medium of a shaft 3| and a gear' wheel 33. Formed in the motion plate isacami slot 23 provided with offset end portions which ex- 35 tend parallel to the direction of motion of the motion plate, and with an intermediate connecting" portion which extends at an angle to the direction of motion of the motion plate,and this slot coopa crates with a roller 34 operatively co-nnected with 4 the operating rod 9 in such manner that the switch, will be moved to its normal or to'its ref verse position according as the motionplate occupies the extreme position shown, or its opposite extreme position. The mechanism also includes a locking plunger iite which cooperates with a pair of aligned notches 48 in a lock rod L secured to the front rod 5 of the switch A. The locking plunger is biased by means of a spring 391i to a locking position in which, when the switch occu 5 pies its normal position, it will enter the notches 48 in the lock rod Land thus'lock the switch in its normal position, but thelocking plunger is arranged to be moved to an unlocking position,- prior to any movement of the switch points away 5 from their normal positions by the mechanism B, by suitable means indicated diagrammatically in the drawings by a lug 42 provided on the motion plate and cooperating with a lug 39d provided on the locking plunger. The locking plunger is also arranged to be moved to its unlocking position, prior to any movement of the switch points away from their normal positions by a trailing train, through the medium of suitable lock releasing linkage including a'bell crank lever 51, substantially as described in the said Bone Patent No. 1,976,827 referred to above.
With the switch A arranged to be operated in the manner described it sometimes happens that a train which has started to trailthe switch stops for one reason or another in a position in which the switch points are held in their trailed positions by the wheels of one of the vehicles of the train, and that, while the points are thus held in their trailed positions, an operator attempts to move the switch to its reverse position by means of the switch operating mechanism B. When this happens, the operation of the mechanism releases the energy stored in the compressed spring of the spring connecting rod C, and causes this energy to be transmitted back through the operating rod 9, roller 34, and inclined portion of the cam slot 28 .to the motion plate 26, and from thence through the gear wheel 33 to the shaft 3|, with the result that the shaft 3| is rotated very suddenly in a counterclockwise direction, as viewed in Fig. 1. Heretofore, it has been customary to secure the hand lever 30 directly to the shaft 3 I, and when the hand lever is secured directly to the shaft, this sudden rotation of the shaft tends to jerk the hand lever out of the operators hand,
thereby creating a dangerous condition, and in some instances causing damage to the apparatus. In accordance with my present invention, I provide means which I shall now describe for connecting the hand lever 30 with the shaft 3| in such manner that the lever will become automatically disconnected from the shaft in the event of rotation of the shaft in response to energy stored in the spring, under the conditions above described.
Referring now also to Figs. 2 to 5, inclusive, as here shown, the lever 30 is formed with a hub 300. having an integral flange 30b provided with a lug 30c, and with a stud 30d carrying a pawl 30c. The hub 30a of the lever is journaled on the outer end of the shaft 3| adjacent to a driving collar 60 which is fixed to the shaft, and formed on the driving collar is a radially extending lug 6| which cooperates with the lug sec on the hand lever.
The lug 6| also cooperates with the pawl 36c, and is provided in one side with a notch 6 la, which, when the parts are in their normal positions in which they are shown in Fig. 3,,receives the upper end ofthe pawl. The pawl is constantly biased to the position in which it enters the notch 6|a by means of a coil spring 62, one end of which extends into a hole 30f in the flange 30b, and the other end of which engages the side of the pawl. The pawl is arranged to be automatically disengaged from the notch in response to rotation of the lever in the direction to move the switch to its reverse position, by means of a trip arm 63, and in order to enable the pawl to be readily disengaged from the notch, the upper end of the pawl and the adjacent side of the notch are rounded in the manner shown. The trip arm 63 is pivoted on a pin 64 mounted in a pair of spaced lugs 65 formed on a frame 66 bolted to the side of the mechanism casing II, and is biased to a position in which a finger 61 formed on the end of the trip arm projects into the path of movement of the pawl by means of a compressed coil spring 68. One end of the spring 68 extends into a cup 69 formed on the trip arm, and the other end extends into a recess formed in the mechanism case. The righthand side of the finger 61, as viewed in Figs. 2 and 3, is beveled at 61a for a purpose which will be made clear presently.
With the lever constructed and arranged in this manner, when the lever is rotated in a counterclockwise direction from the position in which it is shown in Fig. 3 to its opposite extreme position to reverse the switch, the lug 36c will engage the lug 6| on the collar 60, and will thus cause the collar 60 and hence the shaft 3| to rotate in response to the rotation of the lever. During this rotation the pawl 306 will, of course, be rotated with the lever, and as soon as the lever has been rotated a relatively short distance, the'side of the pawl will move into engagement with the side of the trip finger 61, with the result that during the continued rotation of the lever the pawl will be rotated by the trip finger to the position in which it is shown in Fig. 5, in which position it is completely out of the path of movement of the lug 6|. When this happens, if the spring of the connecting rod C is compressed beyond its normal compression, as will be the case if the switch points are then held in their trailed positions by the wheels of a vehicle, the resultant torque which is then exerted on the shaft 3| will cause the shaft and driving collar to rotate rapidly toward their reverse positions, but since the pawl is now out of the path of the lever, the rotation of the shaft will not be transmitted to the lever, and it will be seen, therefore, that the lever will be released of any violent movement.
When the lever '30 has been rotated far enough,
the pawl will swing clear of the trip finger, whereupon the spring 62 will restore the pawl to its normal position; and, when the lever 30 reaches the position corresponding to the position of the collar, the lug 300 will move back into engagement with the lug 6|, and the pawl will swing back into the notch 6 la. If the collar has not reached its full reverse position when this happens, the lug 300 will cooperate with the lug 6| on the collar to complete the movement of the shaft 3|, and thus complete the movement of the switch points. When the lever occupies its full reverse position, the parts will occupy the positions in which they are shown in Fig. 6.
If the switch points are in their normal positions when the lever 30 is operated to reverse the switch points, there will be insufficient force exerted on the shaft 3| and collar 6| by the springs of the spring connecting rod to cause the shaft 3| to rotate in advance of the rotation of the lever, and while the pawl 30c will be moved out of the recess 6|a in the manner above described, the lug 300 will remain in engagement with the lug 6|. As soon as the pawl has cleared the trip finger, it will snap back into place in the notch 6|a.
When the lever has been rotated to its reverse position and it is subsequently operated to restore the switch points to their normal positions, the torque exerted on the lever will be transmitted to the sleeve through the stud 36d and pawl 30a in a manner which will readily be apparent from an inspection of Fig. 6. During this movement, the pawl will engage the beveled face 61a of the trip finger in the manner shown in dotted lines in Fig.
5, and will thus cause the trip finger to move inwardly in opposition to the bias of the spring 68 to a position in which 'it is out of the path of the pawl without causing any displacement of the pawl, such displacement being prevented under these conditions due to the shape of the notch em. As soon as the pawl has passed the trip finger, the trip arm will return to its normal position due to the bias of the spring 68.
Although I have herein shown and described only one form of railway switch operating apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.
Having thus described my invention, what I claim is:
1. In combination, a shaft rotatable between two extreme positions and connected with means which at times tends to rotate said shaft quickly toward one extreme position, a driving collar secured to said shaft and provided with a lug, a manually operable lever journaled on said shaft and provided with a lug which cooperates with the lug on said collar during rotation of said lever in one direction to cause said shaft to rotate in response to rotation of said lever, a pawl pivotally attached to said lever and biased into engagement with the lug on said collar and cooperating with the lug on said collar during rotation of the lever in the other direction to cause said shaft to rotate with said lever, and a trip arm effective to move said pawl out of operative engagement with the lug on said collar during rotation of the lever in one direction to permit said shaft to rotate independently of the lever to prevent the lever from being jerked out of an operators hands.
2. In combination, a shaft rotatable between two extreme positions and connected with means which when the shaft is rotated to either extreme position exerts a yieldable force on it tending to rotate it away from such extreme position, a driving collar fixed to the shaft and provided with a lug, a lever journaled on the shaft and provided with a lug which when the lever is rotated in one direction cooperates with the lug on said collar to rotate said shaft to its one extreme position, a
pawl secured to said lever and biased to a position in which it enters a notch in the lug on said collar and effective during rotation of said shaft in the other direction to rotate said shaft to its other extreme position through the medium of said collar, and a pivoted trip arm biased to a position in which it cooperates with said pawl during rotation of said lever in said one direction to rotate said pawl out of said notch to a position in which said shaft is free to rotate independently of said lever to prevent rotation of the lever by said yieldable force.
3. In combination, a first member rotatable between two extreme positions, a second member rotatable between two extreme positions, a lug on said first member cooperating with a lug on said second member for causing said second member to rotate from one extreme position to another extreme position in response to rotation of said first member from its one extreme position to its other extreme position, a pivoted pawl mounted on said first member, means for holding said pawl in driving engagement with the lug on said second member during rotation of said first member from its other extreme position to its one extreme position, and other means for moving said pawl out of the path of movement of the lug on said second member during at least a part of the movement of said second member in response to movement of said first member toward its other position, whereby said second member is constrained to rotate to either extreme position in response to rotation of said first member to the corresponding extreme position but is free to rotate toward its other extreme position independently of said first member in response to a. force applied thereto by means other than said first member.
WILLIAME. SMITH.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US284033A US2224413A (en) | 1939-07-12 | 1939-07-12 | Railway switch operating apparatus |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US284033A US2224413A (en) | 1939-07-12 | 1939-07-12 | Railway switch operating apparatus |
Publications (1)
Publication Number | Publication Date |
---|---|
US2224413A true US2224413A (en) | 1940-12-10 |
Family
ID=23088599
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US284033A Expired - Lifetime US2224413A (en) | 1939-07-12 | 1939-07-12 | Railway switch operating apparatus |
Country Status (1)
Country | Link |
---|---|
US (1) | US2224413A (en) |
-
1939
- 1939-07-12 US US284033A patent/US2224413A/en not_active Expired - Lifetime
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2224413A (en) | Railway switch operating apparatus | |
US1824150A (en) | Brake for railroad switch machines | |
US2355989A (en) | Slow release lock for railway switches | |
US2371064A (en) | Railway switch operating apparatus | |
US2320171A (en) | Railway switch operating apparatus | |
US778262A (en) | Railway-switch. | |
US2659812A (en) | Switch machine | |
US2380145A (en) | Railway switch operating apparatus | |
US1027468A (en) | Switch mechanism. | |
US1569694A (en) | Railroad switch | |
US2312019A (en) | Railway switch operating apparatus | |
US2309252A (en) | Means for limiting the acceleration of machine elements | |
US678752A (en) | Automatic means for throwing switches. | |
US2677048A (en) | Dragging equipment detector | |
US1989128A (en) | Railway switch circuit controller | |
US1976829A (en) | Railway switch operating apparatus | |
US2168796A (en) | Railway switch operating apparatus | |
US2598495A (en) | Railway switch operating apparatus | |
US833601A (en) | Automatic safety railway-switch. | |
US1554543A (en) | Locking device for interlocking switch stands | |
US2492374A (en) | Railway switch operating apparatus | |
US256102A (en) | Switch-operating device | |
US700811A (en) | Switch and frog. | |
US395452A (en) | Interlocking switch and signal | |
US857291A (en) | Switch-stand. |