US2046893A - Railway switch operating apparatus - Google Patents
Railway switch operating apparatus Download PDFInfo
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- US2046893A US2046893A US49744A US4974435A US2046893A US 2046893 A US2046893 A US 2046893A US 49744 A US49744 A US 49744A US 4974435 A US4974435 A US 4974435A US 2046893 A US2046893 A US 2046893A
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- slide bar
- roller
- dog
- switch
- dogs
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- 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
Definitions
- My invention relates to railway switch operating apparatus, and particularly to apparatus of the type involving a longitudinally movable slide bar coacting with elements for causing operation of a railway switch.
- One object of my invention is the provision of a novel and improved friction lock device for preventing creeping of the slide bar from either of its extreme positions.
- Fig. l is a top plan view showing a railway switch A actuated by one form of switch operating mechanism B embodying my invention.
- Fig. 2 is an enlarged top plan View of a portion of the: mechanism shown in Fig. 1, with the top plate I8 and circuit controller C removed to better illustrate the construction.
- Fig. 3 is a front view of a portion of the mechanism shown in Fig. 2.
- the reference character A designates a railway switch comprising as usual two fixed rails I and I a and two movable switch points 2 and 2
- the fixed rails I and I are laid on tie plates 3 and are secured to crossties 4 in the usual manner.
- the switch points 2 and 2 are connected together by a front rod 5, a head rod 6, and a. tie rod 6 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 I and the usual switch basket 8.
- a switch operating mechanism B which is connected with the head rod 6 through the medium of an operating rod I and the usual switch basket 8.
- the swtch point 2 engages the fixed rail I, and the switch point 2* is spaced a predetermined distance from the fixed rail I
- the switch point 2 engages the fixed rail I a and the switch point 2 is spaced from the fixed rail I.
- the switch operating mechanism B is mounted on a bed plate 9 which is secured to the ties 4 adjacent the outer side of the rail I, and in the form here shown, this mechanism comprises a base plate In (see Figs. 2 and 3), bolted to the bed plate 9, and carrying a longitudinally movable slide bar II which is guided between rollers journalled on studs which project upwardly from the base plate.
- the slide bar I I is adapted to be reciprocated between two extreme positions, and for this purpose the slide bar is operatively connected with the piston rod I2 of a fluid pressure motor I3 which is bolted to the base plate I0.
- the slide bar is connected with the piston rod I2 at the left-hand end of the slide bar, but it should be pointed out that in actual practice the slide bar will usually be so constructed and the parts will be so arranged that the slide bar can be connected with the piston rod of the motor I3 at whichever end of the slide bar proves to be the most convenient for any particular installation, and the bed plate 9 will usually be drilled in such manner that the 15 motor can be bolted to the bed plate at either end of the slide bar.
- the slide bar II consists of an upper bar II and a lower bar II riveted together in superposed parallel spaced relation.
- a roller I5 is rotatably mounted between the bars I I and N and this roller coacts with an alligator jaw I6 which is journalled at its lower end in the base plate I and at its upper end in a top plate I8.
- the top plate I8 is boltedto the base plate I0 in parallel spaced relation and serves to prevent vertical displacement of the slide bar II between its roller guides.
- the alligator jaw I6 is operatively connected with the previously described operating rod 1 in the usual and well known manner.
- the slide bar I I carries two locking dogs I9 and 20 which are attached to the upper and lower bars I I and II respectively, and which cooperate with suitable notches I9 and 20 respectively, formed in an adjustable lock rod L.
- the lock rod -L is of the usual and well-known construction, and is connected to the front-rod of the switch A in the usual manner.
- my improved friction lock is disposed on the side of the slide bar opposite to the alligator jaw I6 and in transverse alignment with the alligator jaw, and in the form here shown, this look comprises a curved dog 2
- a socket 25 Formed on the inner side of the dog 23 directly opposite, and in alignment with, a tapped hole 24 which is provided in theright-hand end of the dog 2
- the roller I5 when the slide bar is being moved to an extreme or looking position after reversal of the switch points, the roller I5 then cooperates with a side surf-ace 2
- a railway switch actuating mechanism comprising a slide bar movable longitudinally between two extreme positions and operatively connected with the switch, a roller carried by said slide bar, two dogs pivotally mounted for rotation about a common axis, and means for biasing said dogs to such position that the one dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies one extreme position and that the other dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies the other 6 extreme position.
- a railway switch actuating mechanism comprising a slide bar movable longitudinally between two extreme positions and operatively connected with the switch, a roller carried by said slide bar, two dogs pivotally mounted for rotation about a common axis, and a single spring operatively connected with both dogs for biasing said dogs to such positions that the one dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies one extreme position and that the other dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies the other extreme position.
- a railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar and two dogs pivoted for rotation about a common axis and biased by means of a single spring to positions for engagement with said roller.
- a railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar, and two dogs pivoted for rotation about a common axis and biased by means of a single spring to such positions that the ends of said dogs extend into the path of movement of said roller.
- a railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar, and two dogs pivoted for rotation about a common axis and biased by means of a single spring to such positions that the ends of said dogs extend into the path of movement of said roller adjacent the two positions respectively which the roller occupies when said slide bar is in two extreme positions.
- a railway switch actuating mechanism comprising a slide bar longitudinally movable be tween two extreme positions and oDeratively con nected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar, and two dogs pivoted for rotation about a common axis and biased by means of a single spring to such positions that the ends of said dogs extend into the path of movement of said roller, the ends of said dogs being disposed at an acute angle to the path of movement of said roller.
- a railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar, and two dogs pivoted for rotation about a common axis and biased by means 5 of a single spring to such positions that the ends of said dogs extend into the path of movement of said roller, the ends of said dogs being disposed at an acute angle to the path of movement of said roller adjacent the positions which 10 said roller occupies when said slide bar occupies its extreme positions.
- a railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions, a roller carried by 15 said slide bar, an alligator jaw operated by said roller for moving the switch, two dogs pivotally mounted for rotation about a common axis, and means for biasing said dogs to such positions that the one dog will coact with said roller to prevent 20 creeping of said slide bar when said slide bar occupies one extreme position and that the other dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies the other extreme position.
- a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, of means for preventing creeping of said slide bar from either of 30 its extreme positions, said means comprising a roller carried by said slide bar, a first curved dog mounted intermediate its ends on a rotatable pin,
- a second curved dog pivoted at one end on said pin and provided with bifurcations which strad- 35 dle the one end of said first dog, said first dog being provided in its one end with a socket, and said other dog being provided intermediate its ends and opposite said socket with a screw threaded hole, a plug screwed into the outer end of 40 said hole, and a compressed spring having one end disposed in said socket and the other end disposed in said hole and engaging said plug for biasing said dogs to predetermined positions, the parts being so proportioned that when said dogs 45 occupy the positions to which they are biased the free end of the one dog will extend into the path of movement of said roller close to the position which said roller occupies when said slide bar occupies its one extreme position and the free end of the other dog will extend into the path of movement of said roller close to the position which said roller occupies when said slide bar occupies its other extreme position.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Railway Tracks (AREA)
- Train Traffic Observation, Control, And Security (AREA)
Description
July 7, 1936. H. L. BONE 2,046,893
RAILWAY SWITCH OPERATING APPARATUS Original Filed April 13, 1933 [25 flerbe ig zv on BY @Kq/Li HIS ATTORNEY Patented July 7, 1936 UNITED STATES PATENT OFFICE RAILWAY SWITCH OPERATING APPARATUS Herbert L. Bone, Pittsburgh, Pa., assignor to The. Union Switch & Signal Company, Swissvale, Pa'., a corporation of Pennsylvania 9 Claims.
My invention relates to railway switch operating apparatus, and particularly to apparatus of the type involving a longitudinally movable slide bar coacting with elements for causing operation of a railway switch.
One object of my invention is the provision of a novel and improved friction lock device for preventing creeping of the slide bar from either of its extreme positions.
The present application isa division of my copending application, Serial No. 665,914, filed on April 13, 1933, for Railway Switch Operating Apparatus.
I will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims.
In theaccompanying drawing, Fig. l is a top plan view showing a railway switch A actuated by one form of switch operating mechanism B embodying my invention. Fig. 2 is an enlarged top plan View of a portion of the: mechanism shown in Fig. 1, with the top plate I8 and circuit controller C removed to better illustrate the construction. Fig. 3 is a front view of a portion of the mechanism shown in Fig. 2.
Similar reference characters refer to similar parts in all three views.
Referring first to Fig. 1, the reference character A designates a railway switch comprising as usual two fixed rails I and I a and two movable switch points 2 and 2 The fixed rails I and I are laid on tie plates 3 and are secured to crossties 4 in the usual manner. The switch points 2 and 2 are connected together by a front rod 5, a head rod 6, and a. tie rod 6 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 I and the usual switch basket 8. When the switch occupies its normal position, in which position it is shown in Fig. 1, the swtch point 2 engages the fixed rail I, and the switch point 2* is spaced a predetermined distance from the fixed rail I When the switch is reversed, however, the switch point 2 then engages the fixed rail I a and the switch point 2 is spaced from the fixed rail I.
The switch operating mechanism B is mounted on a bed plate 9 which is secured to the ties 4 adjacent the outer side of the rail I, and in the form here shown, this mechanism comprises a base plate In (see Figs. 2 and 3), bolted to the bed plate 9, and carrying a longitudinally movable slide bar II which is guided between rollers journalled on studs which project upwardly from the base plate. The slide bar I I is adapted to be reciprocated between two extreme positions, and for this purpose the slide bar is operatively connected with the piston rod I2 of a fluid pressure motor I3 which is bolted to the base plate I0. As shown in the drawing, the slide bar is connected with the piston rod I2 at the left-hand end of the slide bar, but it should be pointed out that in actual practice the slide bar will usually be so constructed and the parts will be so arranged that the slide bar can be connected with the piston rod of the motor I3 at whichever end of the slide bar proves to be the most convenient for any particular installation, and the bed plate 9 will usually be drilled in such manner that the 15 motor can be bolted to the bed plate at either end of the slide bar.
As best seen in Fig. 3, the slide bar II consists of an upper bar II and a lower bar II riveted together in superposed parallel spaced relation. A roller I5 is rotatably mounted between the bars I I and N and this roller coacts with an alligator jaw I6 which is journalled at its lower end in the base plate I and at its upper end in a top plate I8. The top plate I8 is boltedto the base plate I0 in parallel spaced relation and serves to prevent vertical displacement of the slide bar II between its roller guides. The alligator jaw I6 is operatively connected with the previously described operating rod 1 in the usual and well known manner.
In addition to carrying the roller IS, the slide bar I I carries two locking dogs I9 and 20 which are attached to the upper and lower bars I I and II respectively, and which cooperate with suitable notches I9 and 20 respectively, formed in an adjustable lock rod L. The lock rod -L is of the usual and well-known construction, and is connected to the front-rod of the switch A in the usual manner. The parts which have thus far been described are in widespread use, and their operation is well understood, so that for purposes of the present disclosure, it is believed that the following brief description of the operation of these parts will be sufiicient.
When the slide bar I I occupies its extreme normal position, in which position it is shown in the drawing, the switch points are held in their normal positions by engagement of the roller I5 with the right-hand side of the alligator jaw I6, and under these conditions, the locking dog I9 enters the notch I9 in the lock rod L and locks the switch points in their normal positions. When, however, the slide bar is moved from its extreme normal position to its extreme reverse P ition,
the first part of the movement of the slide bar withdraws the locking dog I 9 from the notch It in the lock rod L to unlock the switch, the intermediate part of the movement of the slide bar causes the switch points to be moved to the extreme position opposite to that in which they are shown in Fig. l, and the final part of the movement of the slide bar moves the locking dog 20 into engagement with the notch 2|] in the lock rod L to lock the switch points in their re' verse positions. The operation of the apparatus when the slide bar is subsequently restored to its extreme normal position is exactly the reverse of that just described and will be obvious from an inspection of the drawing.
It has been found that under some conditions there is a tendency for the slide bar H to creep away from the extreme position which it occupies when the switch operating mechanism is at rest, this tendency probably being due to vibration caused by passing trains. When such creepage occurs, it is manifest by the fact that the signals which govern traffic over the switch cannot be cleared because of the control of these signals by an indication circuit controller C which is controlled in part by the slide bar, and which is described in detail in my copending application, Serial No. 665,914, of which the present application is a division. It is obvious, therefore, that this creepage of the slide bar is undesirable, and one of the objects of my invention is to provide a friction lock which prevents this creepage, my friction lock being an improvement over that shown and described in Letters Patent of the United States No. 1,732,957, granted to Charles Thorn and William C. Mc- Whirter, on October 22, 1929, for Railway switch operating 7 mechanism.
Referring now again to Figs. 2 and 3, my improved friction lock is disposed on the side of the slide bar opposite to the alligator jaw I6 and in transverse alignment with the alligator jaw, and in the form here shown, this look comprises a curved dog 2| secured intermediate its ends to a pin 22 which is 'journalled in the base plate l0 and top plate l8, and a curved dog 23 which is mounted to rotate at one end on the pin 22, the dog 23 being provided with bifurcations which straddle the right-hand end of the dog 2|, as shown in Fig. 3." Formed on the inner side of the dog 23 directly opposite, and in alignment with, a tapped hole 24 which is provided in theright-hand end of the dog 2| is a socket 25; and interposed between the socket 25 and an adjustable plug 26 which is screwed into the outer end of the hole 24, is a compressed coil spring 21 which biases the dogs 2| and 23 to the positions in which the inner ends of these dogs extend part way into the path of movement of the roller'|5, the dogs being stopped in the desired positions by means of stop pins 28 extending upwardly from the base plate [0. The parts are so proportioned that when the slide bar II is inits extreme normal position in which it is shown in the drawing, the end surface 23 of the dog 23 will be very close to the lower left-hand side of the roller I5, as viewed in Fig. 2, and that, when the slide bar occupies its opposite or reverse extreme position, the end surface 2| of the dog 2| will be located very close to the lower right-hand side of the roller 5. Furthermore, the end surface of both'of these dogs is disposed at an acute angle to the'path of movement of the roller I5, as will be apparent from an inspection of Fig. 2. It will be seen,
therefore, that when the slide bar occupies its extreme normal position, it cannot move out of this position unless sufiicient force is exerted on it to force dog 23 back against the opposing force of spring 2'! a sufficient amount to permit roller l5 to clear the end surf-ace 23 of dog 23, and that, when the slide bar occupies its extreme reverse position, it cannot move out of this position unless sufiicient force is exerted on it to cause dog 2| to be forced back against the opposing force of spring 21 a sufficient distance to permit roller |5 to clear the end surface 2| of the dog 2|. The amount of compression of spring 2! will usually be so adjusted that the force required to move the dogs out of the path of movement of the roller l5 will be greater than any force tending to cause the slide bar to creep, but will not be enough to interfere with the movement of the slide bar by the motor. In this connection, it should be pointed out that the necessary operation of the friction look by the motor takes place during the unlocking and locking portions of the stroke of the slide bar, and the load on the motor at this time is much less than it is during that portion of the stroke of the slide bar in which the reversal of the switch points occurs, so that the force available to operate the lock is more than ample. Furthermore, when the slide bar is being moved to an extreme or looking position after reversal of the switch points, the roller I5 then cooperates with a side surf-ace 2| on the dog 2|, or a side surface 23" on the dog 23 as the case may be, and not with the end surface of these dogs; and the side surfaces 2| and 23 are disposed at such angles 3 with respect to the path of movement of the roller that the force Which the slide bar must exert when the roller is engaging one of these surfaces, in order to move the associated dog out of the path of movement of the roller, is considerably less than that required to move such dog out of the path of movement of the roller when the slide bar is being moved away from an extreme position.
Although I have herein shown and described only one form of railway switch operating apparatus embodying my invention, it is widerstood 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. A railway switch actuating mechanism comprising a slide bar movable longitudinally between two extreme positions and operatively connected with the switch, a roller carried by said slide bar, two dogs pivotally mounted for rotation about a common axis, and means for biasing said dogs to such position that the one dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies one extreme position and that the other dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies the other 6 extreme position.
2. A railway switch actuating mechanism comprising a slide bar movable longitudinally between two extreme positions and operatively connected with the switch, a roller carried by said slide bar, two dogs pivotally mounted for rotation about a common axis, and a single spring operatively connected with both dogs for biasing said dogs to such positions that the one dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies one extreme position and that the other dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies the other extreme position.
3. A railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar and two dogs pivoted for rotation about a common axis and biased by means of a single spring to positions for engagement with said roller.
4. A railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar, and two dogs pivoted for rotation about a common axis and biased by means of a single spring to such positions that the ends of said dogs extend into the path of movement of said roller.
5. A railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar, and two dogs pivoted for rotation about a common axis and biased by means of a single spring to such positions that the ends of said dogs extend into the path of movement of said roller adjacent the two positions respectively which the roller occupies when said slide bar is in two extreme positions.
6. A railway switch actuating mechanism comprising a slide bar longitudinally movable be tween two extreme positions and oDeratively con nected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar, and two dogs pivoted for rotation about a common axis and biased by means of a single spring to such positions that the ends of said dogs extend into the path of movement of said roller, the ends of said dogs being disposed at an acute angle to the path of movement of said roller.
'7. A railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, and means for preventing creeping of said slide bar from either of its extreme positions comprising a roller carried by said slide bar, and two dogs pivoted for rotation about a common axis and biased by means 5 of a single spring to such positions that the ends of said dogs extend into the path of movement of said roller, the ends of said dogs being disposed at an acute angle to the path of movement of said roller adjacent the positions which 10 said roller occupies when said slide bar occupies its extreme positions.
8. A railway switch actuating mechanism comprising a slide bar longitudinally movable between two extreme positions, a roller carried by 15 said slide bar, an alligator jaw operated by said roller for moving the switch, two dogs pivotally mounted for rotation about a common axis, and means for biasing said dogs to such positions that the one dog will coact with said roller to prevent 20 creeping of said slide bar when said slide bar occupies one extreme position and that the other dog will coact with said roller to prevent creeping of said slide bar when said slide bar occupies the other extreme position.
9. In a railway switch actuating mechanism the combination of a slide bar longitudinally movable between two extreme positions and operatively connected with the switch, of means for preventing creeping of said slide bar from either of 30 its extreme positions, said means comprising a roller carried by said slide bar, a first curved dog mounted intermediate its ends on a rotatable pin,
a second curved dog pivoted at one end on said pin and provided with bifurcations which strad- 35 dle the one end of said first dog, said first dog being provided in its one end with a socket, and said other dog being provided intermediate its ends and opposite said socket with a screw threaded hole, a plug screwed into the outer end of 40 said hole, and a compressed spring having one end disposed in said socket and the other end disposed in said hole and engaging said plug for biasing said dogs to predetermined positions, the parts being so proportioned that when said dogs 45 occupy the positions to which they are biased the free end of the one dog will extend into the path of movement of said roller close to the position which said roller occupies when said slide bar occupies its one extreme position and the free end of the other dog will extend into the path of movement of said roller close to the position which said roller occupies when said slide bar occupies its other extreme position.
HERBERT L. BONE.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US49744A US2046893A (en) | 1933-04-13 | 1935-11-14 | Railway switch operating apparatus |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US665914A US2082142A (en) | 1933-04-13 | 1933-04-13 | Railway switch operating apparatus |
US49744A US2046893A (en) | 1933-04-13 | 1935-11-14 | Railway switch operating apparatus |
Publications (1)
Publication Number | Publication Date |
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US2046893A true US2046893A (en) | 1936-07-07 |
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Application Number | Title | Priority Date | Filing Date |
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US49744A Expired - Lifetime US2046893A (en) | 1933-04-13 | 1935-11-14 | Railway switch operating apparatus |
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US (1) | US2046893A (en) |
-
1935
- 1935-11-14 US US49744A patent/US2046893A/en not_active Expired - Lifetime
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