US3015724A

US3015724A - Railway skate control system

Info

Publication number: US3015724A
Application number: US760400A
Authority: US
Inventors: Glen V Jefferson
Original assignee: Westinghouse Air Brake Co
Current assignee: Westinghouse Air Brake Co
Priority date: 1958-09-11
Filing date: 1958-09-11
Publication date: 1962-01-02
Anticipated expiration: 1979-01-02

Description

Jan. 2, 1962 v. JEFFERSON RAILWAY SKATE CONTROL SYSTEM 2 Sheets-Sheet 1 Filed Sept. 11, 1958 Jedi 012 I? 7 22 -i b 455 F INVENTOR. Glen VJei'iersozz w- L Qtd HIS ATTORNEY Track Gradejz Jan. 2, 1962 G. v. JEFFERSON RAILWAY SKATE CONTROL SYSTEM 2 Sheets-Sheet 2 Filed Sept. 11, 1958 INVENTOR. Glen I. Jefferson H M o 5 5 csz i /Vmw an MM .H R MM fi Q AQ Q 9 W 3 H o m JWTQRH H15 ATTORNEY United States Patent 3,015,724 RAILWAY SKATE CONTROL SYSTEM Glen V. Jefferson, Edgewood, Pa., assignor to Westinginghouse Air Brake Company, Wilmerding, Pa., a cor poration of Pennsylvania Filed Sept-11, 195s, Ser. No. 760,400 Claims. (Cl. 246-182) My invention relates to railway skate control systems, and more particularly to a skate control system for positioning a skate in response to car movements in designated track sections.

In railway classification yards, skate braking apparatus may be advantageously used for various applications, such as for example, at the exit end of storage tracks. In such an application, skates are used to stop those cars moving along said storage track at an undesirably high velocity sufiicient to cause said cars to move into adjacent departure or ladder tracks instead of stopping within the limits of the storage trackj Heretofore, skate apparatus has been manually placed in a braking position which .operation is expensive, slow, and ineflicient.

' Accordingly, it is a principal object of my invention to provide a control system for positioning of skateapparatus in direct response to the movement of a car over designated track sections. V w

In a classification yard, after the desired cars have been routed to a particular track, a locomotive moves into the storage track from the ladder track to couple and pull the cars out of the storage track. Thus when it is desired to move the cars out of the storage track any skate apparatus positioned on said storage track must be moved from its braking position to a non-braking position in order that it will not interfere with the move ment of the car and the locomotive. Y

It is .therefore another object of my invention to provide track circuitry for controlling movement of a skate between braking and non-braking positions in response to the movement of a vehicle into designated track sections. v i

It is desirable that any skate'apparatus employed positively stop or brake the force of a moving car within a definite predetermined distance. I

. It is therefore still another-object of my invention 1 to provide a skate apparatus including a clutch braking mechanism in which the restraining force of a clutch is utilized in addition to the friction force of the skate on the rail to provide thetotal braking force. V

In theattainment of the foregoing objects, I provide new-andimproved skate braking apparatus for railway cars and control circuitry for automatically positioning ice FIG. 2, and showing a carwheel engaging the skate;

FIG. 4 is a view partially in cross section taken along the lines IV--IV of FIG. 2;

FIG; 5 is an isometric view of a portion of the skate apparatus shown in FIGS. 1-4;

. FIG. 6 is an enlarged cross section of the braking clutch taken along the lines VIVI of FIG. 2; and

FIG. 7 .is a sketch of the track'section indicating a desired grade.

Referring to FIGS. 1, 2, 3 and 7, it will be assumed that railroad cars move from left to right, as oriented in the drawings, along a storage track. 10, and further that it is desired to positively brake or stop the cars on track section 11 of storage track 10. Track 10 may be, for example, a storage track in a gravity type classification yard used for receiving-and storing cars prior to the cars being formed into a train for movement to a desired destination. As is known cars descend from a hump, not shown, in the classification yard and are routed to specific storage tracks. The storage tracks lead into respective ladder or departure tracks over which a' locomotive normally enters the storage track to couple to and pull the cars out of said storage track. Here track 10 is shown as leading into ladder track 19. Rails 10a and 10b of track 10 are supported on ties 21 in the usual manner.

Suitable insulating joints

13, 15 and 17 divide storage track 10 into

twotrack sections

11 and 12.

The car braking means comprises a skate apparatus generally designated as 23 and includes a skate 25; a U-shaped channel 26 on which skate 25 rides; a reversible motive means shown as a motor 27 having an armature 27a, a field winding 27b, and a brush assembly 270; a clutch 29; and a driving chain 31 connected to opposite ends'of skate 25, and circumposed around a driving sprocket wheel 33 and a spaced idler wheel 35. An input worm shaft '37 operatively connects motor 27 to the clutch 29, and an output shaft 59"connects the clutch 29 to the sprocket wheel 33. One end of chain 31 is afiixed, by any suitable means, ot the forward end of skate 25 and the other end of the chain is affixed, also by any suitable means, to the after end of the skate. Skate 25 includes a body portion 25a which rests on and rides on the upstanding legs of channel 26, see FIGJ4; and, a braking portion 25b which rests on and rides on the head or rail 10a, see FIG. 5. A skate shoe 25c, shaped to conform to the circumference of a car wheel, is afiixed to braking portion 25b as by bolt 25d which passes through apertured ears 25e formed on braking portion 25b and through an aperture 25f formed in skate shoe'25c. Skate 25 may also 'be made as one piece;

however since' shoe 25c is subject to considerable wear,

Further, the a and shall pointout the novel features thereof in the appended claims;

Other objects and advantages of my invention. will become apparent from the following description and the accompanying drawings in which; likereference characters refer to corresponding elements, and in which:

FIG. 1 is a diagrammatic view' of the skate apparatus and the circuitry-controlling said-apparatus; 5 1 FIG. 2 is an enlarged plan view of the skate apparatus according to my invention; 5

FIG. 3 is an elevational view' of the apparatus of by forming the brake shoe 250 as a separate piece a more inexpensive and convenient replacement of the skate shoe may be made. j

Skate 25 is guided in channel 2 6 by rollers 41 which rollers rotate on the lower shaft portion 43a of a stud 43 which passes through an aperture 25b"in body portion'25a. Channel 26 is affixed to ties 21by any suitable means and ektendsparallel to rail 10a for'a'prede 1 termineddistancegin one embodiment about 30 feet the right hand or after end of channel .26 angles away from 103. and also downward from" the plane of the rail, FIGS. 2 and 3, for purposes hereinafter explained. 'tAn extension or ramp 45 is disposed with one end abutting railhead 10a and arranged parallel to the angled portion of channel 26. Ramp 45 also angles downward from the horizontal plane of rail 10a. Ties 2 1 are suitably beveled position and a non-braking position, both of saidpositions-being locatedwithin the limitsof track section 11.

The braking position, shown in solid lines in FIGS. 1, 2 and 3, is defined as that position wherein skate 25 rests on the head of rail a and is in a position to initially engage a car wheel moving into track section 11. The non-braking position, shown in dotted lines in FIGS. 1, 2 and 3, is that position wherein skate 25 rests on the angled portion of channel 26 and on ramp 45 oif and away from rail 10a and does not interfere with or affect the movement of cars over the rail.

Referring now to FIG. 6 as well as FIGS. 1 and 2 the braking clutch 29 includes a cup-shaped housing 47 secured, as by bolts 28 passing through apertured extensions 49 to suitably reinforced ties 21a. Housing 47 has an'apertured cover 51 which is secured as by bolts 53 to the housing. A centrally apertured output splined shaft 55 is journaled in a bushing 57 extending through cover 51. Shaft 55 extends upwardly to receive a sprocket wheel 33. Wheel 33 is angularly afiixed relatively to shaft 55 by key 58. A bolt 59 extends downwardly through shaft 55 and is journaled at its lower end in a bearing 61 located in a recess formed at the bottom of housing 47. Bolt 59 is angularly afifixed relatively to shaft 55 by a key 62.

Clutch 29 includes an inverted cup-shaped casing 69 having a centrally apertured web 6% which is spaced from cover 51 of housing 47 by washer 72. The hub of the web 69a has a bushing 71 pressed therein which is in turn rotatably mounted on shaft 55. Clutch 29 further includes a plurality of alternately stacked friction plates 73a and 73b. Plates 73a are splined to the inside surface of casing 69 and extend transversely from the casing 69 toward shaft 55. Plates 73b are splined into shaft 55 and extend transversely toward the inner surface of the easing 69. Plates 73a are arranged to frictionally engage plates 73b. The outer periphery of web 69a is cut to form a worm gear wheel 6% which is driven by an input worm shaft 37. The upper end of bolt 59 receives an adjusting nut 63. A shoulder 59a formed near the lower end of bolt 59 supports an apertured dished, or Bellville type, spring 65 which engages the lower plate of friction clutch 29. Spring 65 cooperates with bolt 59 and nut 63 to adjust the contact pressure between the plates 73a and 73b so as to adjust the rate of retardation of the moving cars.

Worm shaft 37 is of the well known self-locking type and is constructed and arranged relatively to worm gear wheel 69!) so that worm 37 will transmit the motion of motor 27 to wheel 69b. However, worm 67 will lock relatively to gear wheel 69b when a force is applied to sprocket 33. More specifically the motor 27 drives gear wheel 69b and casing 69 through worm 37; friction plates 73a splined to casing 69 are then effective to drive friction plates 73b and shaft 55 connected thereto. Due to the spring load exerted on the friction plates 73a and 73b by spring 65 the rotation of plates 73a are effective to drive plates 73b. The sprocket wheel 33, affixed to shaft is then effective to drive chain 31 and thus move skate 25 between its braking and non-braking positions, as will be further explainedhereinbelow. In contrast, when a car wheel engages and begins to move skate 2.5, sprocket wheel :33 and shaft 55 connected thereto will of course start to rotate. Friction plates 73b affixed to shaft 55 will also start to rotate and engage and attempt to drive plates 73a. Plates 73a, in turn,'will tend to rotate casing 69 and'gear wheel 69b. Because of the self-locking feature of worm shaft 37, gear wheel 69b remains stationary. Consequently, plates 73b rotate relatively to plates 73a and frictionally expend a portion of the kinetic energy of the forceapplied by the movingcar to the chain 31 and sprocket wheel 33. Thus a car tending to move skate 25 is braked.

The circuitry which control s movement of skate 25 in response to the movement of a car into

track sections

11 and 12 is shown in FIG. 1. Skate 25 includes a suitable projection 25h positioned inany convenient place on skate 25 and indicated only schematically in FIG. 1, which during the time skate 25 is in its braking position engages a button 75 of insulative material mounted on the heel contact of a single pole switch 77 and opens said switch. Switch 77 is biased to a normally closed position against its front contact a by a spring 73. Likewise when skate 25 is in its non-braking position projection 25h engages a button 79 of insulative material mounted on the heel contact of a single pole switch 81 and opens said switch. Switch 81 is biased to a normally closed position against its front contact a by a spring 83. The heel contact of each of

switches

77 and 81 are connected to a suitable source of potential here shown'as a battery 85.

The track circuit for

track sections

11 and 12 includes track relays 11TR and 12TR respectively, each having its operating winding connected across rails 10a and 1%. Relay IZTR is energized by a source of potential here shown as a battery 87 connected in series to resistor 86 and across

rails

10a and 10b. Relay 11TR is energized by a source of potential, here shown as a battery 89, which is connected to rails 10a and 16b in series through resistor 88 and over a front contact a of relay 12TR.

Resistors

86 and 88 are the usual current limiting resistors.

As is well known in the art the shunting of a track circuit by the presence of a car in the associated track section will deenergize the associated track relay and will then cause the track relay to release. 1

Assume initially that

track sections

11 and 12 are unoccupiedand that relays 11TR and 12TR are energized. Further assume that skate 25 is in its braking position, as shown in the solid lines in FIG. 1 and 2, and that projection 25h engages button 75 causing switch 77 to be opened. A car moving into track section 11 engages skate 25and moves the skate toward its non-braking position. During movement of the skate, a portion of the kinetic energy of the moving car will be expended by the sliding friction between the wheel of the car and the surface of rail 10a, between the skate 25 and the surface of rail 10a and in the friction plates 73a and 73b of clutch 29. It is desirable that the frictional restraint of clutch 29 be adjusted according to predetermined calculations by means of tension bolt 59 to a value so that the restraining force of the clutch plus the friction between skate 25- and rail 10a dissipates all the kinetic energy of a moving car or cut of cars to completely stop the car or cars within the confines of the skate operating positions. Skate 25 may, depending on the actual velocity and weight of the moving car, stop the car at any intermediate position as the skate is moved toward its extreme non-braking position.

The track section 11 is arranged to have a slight ascending grade, as shown greatly exaggerated in FIG. 7. After being stopped by the skate a car will roll back down the grade, due to gravity, thus clearing track sec tion 11.. As a safety factor, section 12 may also have a grade so that even if a car is not completely braked in section 11 and does move into section 12, gravity will still cause it to roll back down to clear both

track sections

11 and 12.

After the car clears track section 11, the skate 25, must be returned to its braking position in preparation for the next braking operation. With track section'12 unoccupied relay 12TR will be energized by battery 87. Relay llTR will pick up its front contacts a and b since it is energized by battery 89 over a circuit which may be traced from the positive terminal of battery 89, resistor 88, front contact a of relay 12TR, rail 10b, the operating winding of relayl lTR, and back through rail 10a to the negative terminal of battery 89. At thispoint skate 25 has been moved to an intermediate position toward its non-braking position so that switch 77 will be closed, thus energy will be supplied to the armature 27a of motor 27 over a circuit which may be traced from the positive terminal B of battery through front contact a of switch 77, front contact a of relay 11TR, lead 91, lead 92, brushes 27c, and armature 27b of motor 27 to the negative terminal N of battery 85. Likewise energy will be supplied to the field winding 27b of motor 27 over a circuit which may be traced from terminal B of battery 85 through front contact a of switch 77, front contact b of relay 11TR, lead 93, front contact d of relay 12TR, lead 95, field winding 27b, lead 97, and front contact e of relay 12TR to terminal N of battery 85. Motor 27 will now be energized to drive skate 25 toward its braking position by means of worm shaft 37, casing 69, sprocket wheel 33 and chain 31. Motor 27 will continue to operate until skate 25 reaches its braking position where projection 25h engages button 75 and opens switch 77.

Assume now that it is desired to move-the cars out of a storage track. To couple to the cars, it is necessary for a locomotive to enter the storage track from the ladder track 19 and move through

track sections

12 and 11, in that order, and without engaging or being obstructed by a skate 25. When the locomotive moves into track section 12, energy from battery 87 to relay 1'2TR will of course be shunted by the locomotive wheels and relay 12TR will release. As is obvious, release of relay 12TR opens its front contacts and closes its back contacts. By opening front cont-act a of relay 12TR, energy coupled from battery 89 to'relay 11TR, over the circuit previously traced, will be interrupted and relayllTR will release. At this time skate 25 is in its braking position, so that front contact a of switch 81 will be closed. Consequently, energy will be supplied to the brushes 27c and armature 27b of motor 27 over a circuit which maybe traced from terminal B of battery 85, through frontcontact a of switch 81, back contact b of relay 12TR, lead 91, lead 92, brushes 27c, and armature 27a to terminal N of battery 85.

To move the skate from its braking position to its nonbnaking position, it is necessary that the direction of rotation of motor 27 be reversed to drive sprocket wheel 33 andchain 31 in a direction to move'skate 25 on rail 10a to its non-braking position. As is known, the rotation of motor 27 may be reversed by reversing the flow of current energy through the field winding 27b of the motor. Therefore, in order to reverse the rotation of motor 27 energy is supplied to the field winding 27b over a circuit which may be traced from terminal B of battery 85, through front contact a of switch 81, back contact of relay 12TR, back contact d of relay 12TR, lead 97, field winding 27b,

lead 95, and back contact e of relay 12TR to terminal N of battery 85.

Thus in a first case, when skate 25 is in an intermediate position or at its non-braking position the field winding 27b is energized so that sprocket wheel and chain 31 are rotated to move skate 25 to its initial braking position. Likewise, in a second case, when skate 25 is in its braking position the field winding 27b is energized by current flowing in a reverse direction to that of the first case so that sprocket wheel 33 and chain 31 are rotated to move skate 25 from its braking position to its non-braking position.

The operation of my control system will now be briefly summarized. Assume initially that skate 25 is in its braking position and that a car or cut of cars is routed to storage track 10. Should the out be moving on track at a velocity greater than that desired, the cut will move into track section 11 and a wheel of the leading car will engage skate 25. As the wheel of the lead car moves the skate 25 over rail 10a the kinetic energy of the cut-of cars is expended by clutch 29 and skate 25 as previously described and the cut of cars is brought to a smooth stop.

After stopping, the cars will roll back down the track grade, thus clearing

track sections

11 and 12. Skate 25 will, at this time, have been moved toward its non-braking position. With track relays 11TR and 12TR both energized and since front contact a'of switch 77 is closed, energy will be supplied to the brushes 27c and armature 27a of motor 27 and to field winding 27b of motor 27 causing the said motor to rotate in a desired direction to return skate 25 to its initial braking position where projection 27h on skate 25 opens switch 77 and interrupts energy When it is desired to move the cars out of storage track 10, a locomotive will move into track 10 from ladder track 19. Skate 25 will at this time be at its braking position and front contact a of switch 81 will be closed. When the locomotive shunts track Section 12 relay 12TR releases, thus also causing relay 11TR to release. Energy will be supplied over front contact a of switch 81 to the brushes 27c and armature 27b of motor 27. Energy will now be supplied to the field Winding 27b of motor 27 in a direction reversed relatively to the direction of energy supplied when the skate was in its non-braking position. Skate 25 will be moved to its non-braking posit-ion so as not to obstruct the movement of the locomotive. When the locomotive and all the cars clear the

track sections

11 and 12, relays 12TR and 11TR will be energized by their respective batteries to provide energizing circuits for motor 27 to return skate 25 to its initial braking position.

While my inventon has been described with reference to a particular embodiment thereof, it will be understood that various modifications may be made by those skilled in the art without departing from. the invention. The appended claims are therefore intended to cover all such modifications within the true spirit and scope of the invention.

Having thusdescribed my invention, what I claim is:

1. In combination with a track rail, skate operating apparatus including a skate movable along said rail between a car braking position on the rail and a non-braking position off and away from said rail, said skate arranged in the braking position to engage a car moving on said rail, friction between said skate and said rail braln'ng said car, motive means, control circuits for said motive means, clutch means including friction plates and a drive shaft, said motive means connecting through said plates and said shaft between its braking and non braking positions, and said clutch means including means for locking a first group of friction plates relative to a second group of friction plates, said second group of friction plates being rotated due to movement of said skate by a car whereby said second group of friction plates slides on said first group of plates for dissipating a portion of the kinetic energy of a moving car to add to the total braking force of said skate.

2. In combination with a pair of railway track sections at least the first of said track sections having a grade,

skate operating apparatus including'a skate movable by a car, said friction plates dissipating a portion of the kinetic energy of a moving car for complementing the frictional braking force of said skate, said car after being stopped moving down said grade to clear said first track section, motive means, said clutch means connecting said motive means through said friction plates to move said skate, and control means for energizing said I motive means to return said skate to its braking position when said car clears said first track section.

3. In combination with first and second railway track sections, said first track section having a grade, a, skate operating apparatus including a skate, movable along a' rail of said first track section between a car braking posif tion on the rail and a non-braking'position ofi and away from said rail, in the braking position said skate arranged to engage and brake a moving car approaching from a first direction and up said grade, said skate being moved by said car from its braking to its non-braking position, said car when stopped then moving down said grade to clear saidfirst track section, a first control means associated with said first track section for returning said skate to its braking position when said car clears said first track section, a second control means associated with said first track section for moving said skate to its non-braking position when said second track section is occupied.

4. In combination, with first and second railway track sections, said first track section having a grade, a skate operating apparatus including a skate movable along a rail of: said first track section between a car braking position and a non-braking position oif and away from said rail, in said braking position said skate arranged to engage and stop a moving car approaching from a first direction up said grade, and said skate moved by said car from its braking position to its non-braking position, after being stopped said car then moving back down said grade to clear said first track section,'a first control means associated with said first track section for returning said skate to its braking position. when said car clears said first track section, a second control means associated with said second track section for moving said skate to its non-braking position when said second track section is occupied and said first track section is clear.

5. In combination, with first and second railway track sections, said first track section having a grade, a skate operating, apparatus including a skate movable along a rail of said first track section between a vehicle braking position on the rail and a non-braking position 01? and away from said rail, in said braking position said skate arranged to engage and stop a moving vehicle approaching from a first direction up said grade as said skate is moved by said vehicle from its braking position toward its non-braking position, said vehicle after being stopped then moving back down said grade to clear said first track section, a first and a second relay having from; and back contacts associated with said first and second track sections respectively, said relays being normally, energized, each of said relays being deenergized when avehicle is present in the associated track section, said first'relay being energized over a from contact of said second relay, reversible rotative motive means, means operatively conmeeting said motive means to said skate, said motive means being efiective to move said skate between its braking and non-braking positions, said motive means being energized over the front contacts of said first relay and the front contacts of said second relay to rotate in a direction to move said skate from its non-braking to its braking position and said motive means being energized over the back contacts of said second relay to rotate in a relatively reversed direction to move said skate from its "braking to its non-braking position, said first relay being energized to cause said motive means to move said skate from its non-braking position to its braking position only when both said track sections are clear, and deenergization of said second relay before deenergization of said first relay causing said motive means to move said skate from its braking position to its nons braking position.

References Cited in the file of this patent UNITED STATES PATENTS UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent No, 3 O15,724 January 2, 1962 Glen V, Jefferson It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 6 line 43, after "shaft" insert to move said skate Signed and sealed this 24th day of April 1962 (SEAL) Attestz- ESTON Go JOHNSON DAVID L LADD Attesting Officer Commissioner of Patents