US3306233A

US3306233A - Railway car holder assembly

Info

Publication number: US3306233A
Application number: US346649A
Authority: US
Inventors: Wallace J Saxonmeyer
Original assignee: Whiting Corp
Current assignee: Whiting Corp
Priority date: 1964-02-24
Filing date: 1964-02-24
Publication date: 1967-02-28
Anticipated expiration: 1984-02-28

Description

Feb. 1967 w. J. SAXONMEYER 3,306,233

RAILWAY CAR HOLDER ASSEMBLY 4 Sheets-Sheet 1 Filed Feb. 24, 1964 v I INVENTOR. WALLACE J. SAXO/VA/fY/FA uwkw l l hfl l uhl h k l h llllL II |l\ v\ E. QM Q ww m mm u GM ATTOR VE Y5 1967 w. J. SAXONMEYER 3,306,233

RAILWAY CAR HOLDER ASSEMBLY 4 Shets-Sheet 2 Filed Feb. 24, 1964 INVENTOR. WAL LACE SAXONMEYER BY LM, W ATTORNEYS 1967 w. J. SAXONMEYER RAILWAY CAR HOLDER ASSEMBLY 4 Sheets-Sheet 3 Filed Feb. 24, 1964 INVENTOR. WALLACE J. SAXO/VMEYER G: k /w-Q T; Lar LJ-u-aul 0 ATTORNEYS United States Patent ()fifice 3,396,233 Patented Feb. 28, 1967 3,306,233 RAILWAY CAR HOLDER ASSEMBLY Wallace J. Saxonmeyer, Park Forest, Ill., assignor to Whiting Corporation, a corporation of Illinois Filed Feb. 24, 1964, Ser. No. 346,649 9 Claims. (Cl. 104-249) This invention relates to devices for holding one or more railway cars on a section of track, and more particularly to a new and improved car holder assembly of the type adapted to be mounted between rails of a track for engagement with the axle of a car to act as a stop against movement of the car in one direction and to permit movement of the car in an opposite direction.

A car holder of the type mentioned above is fixedly mounted between rails of track in a siding or yard, for example. The car holder is provided with collapsible means which include a member which is engaged by a railway car axle when the collapsible means is erected and which is cleared by a railway car axle when the collapsible means is collapsed. The collapsible means are designed so as to support the axle engaging member in a manner to act as a stop against movement of a car in one direction and to permit movement of a car in an opposite direction.

In practice, this type of car holder is mounted between rails of track section having a slight grade. A railway car is switched onto this graded track section and allowed to travel along the same until it contacts the car holder thereby coming to a sudden stop. Another car is then switched onto this track section and allowed to couple with the first car which is held by the car holder. Additional cars are switched onto the track section until the desired number of cars are coupled together. It will be realized that the car holder engaging the first car switched on the track section acts to hold all of the other cars coupled with this first car. When it is desired to remove these cars from the section of track, a switch engine or the like is coupled with the last car on the graded track section and then operated to pull the cars up this track section onto another section or length of track.

It Will be realized that the coupling of these cars with each other and with a switch engine or the like produces coupling shocks of considerable magnitude which are transferred to the car holder through the car axle which is engaged by the car holder. If these coupling shocks are excessive, damage may result to the car holder or to the railway car axle or both.

Accordingly, it is a primary object of the present invention to provide a new and improved railway car holder assembly which has the ability to absorb coupling shocks so as to prevent damage to the car holder and to the railway car truck assembly having the axle which is engaged by the car holder.

Another object of the present invention is the provision of a railway car holder having an axle engaging member supported by new and improved collapsible means so as to adapt the car holder for acting as a stop against movement of the car in one direction thereof and for permitting movement of the car in an opposite direction.

A further object of the present invention is the provision of a new and improved railway car holder assembly which is adapted to absorb considerable coupling shocks and which minimizes the possibility of derailment of the railway car truck assembly having the axle engaged by the car holder.

A still further object of the present invention is the provision of a new and improved railway car holder assembly which is adapted to absorb considerable coupling shocks thereby substantially reducing the possibility of failure of the railway car axle engaged by the car holder,

and which is adapted to engage the car axle in a manner tending further to reduce the likelihood of axle failure.

These and other objects and advantages of the invention will become apparent from the following specification disclosing a preferred embodiment of the invention which is illustrated in the accompanying drawings.

In the drawings:

FIG. 1 is a fragmentary, partially broken away, top plan view of the railway car holder assembly of this invention;

FIG. 2 is a fragmentary, partially broken away, top plan view of the railway car holder assembly, this figure being a continuation of FIG. 1 from the right end thereof;

FIG. 3 is a vertical section taken along line 3-3 of FIG. 1, which line represents the longitudinal center line of the car holder assembly;

FIG. 4 is a vertical section taken along line 4-4 of FIG. 2, which line represents the longitudinal center line of the car holder assembly;

FIG. 5 is a side elevational view of one of the car holders showing the collapsible means thereof in the erected position;

FIG. 6 is a side elevational view of one of the car holders showing the collapsible means thereof in the collapsed position;

FIG. 7 is a top plan view of one of the car holders;

FIG. 8 is an enlarged section taken along line 88 of FIG. 7; and

FIG. 9 is an enlarged section taken along line 9-9 of FIG. 4.

Briefiy and by way of introduction, the railway car holder assembly includes a pair of side-by-side car holders mounted between rails of a track section in parallel relation with the latter. The car holders are mounted by separate track means for movement in either direction along a rectilinear path which is parallel to the direction of car movement on the track section. Each car holder includes a railway car axle engaging member supported by collapsed means forming a part of the car holder. Both car holders are fastened to a cross link member which is connected with a cushioning device anchored between the rails of track in spaced relation with the car holders. The cushioning device serves to resiliently mount the car holders to allow the latter to yield as they are struck by a car axle thereby adapting the assembly to absorb coupling shocks so as to minimize substantially the possibility of damage to the car holders and/ or to the railway car axle contacted thereby.

Referring now to the drawings, the railway car holder assembly of this invention includes a pair of car holders, generally designated 10 (FIGS. 5-7), mounted side-byside between rails of a track section and extending longitudinally of the latter. As both car holders are of identical construction, only one car holder 10 is illustrated and described.

Car holder 10, which is of the type of device often referred to as a rabbit, includes a pair of

parallel beams

12 and 14 which are secured together in spaced relation by a pair of

elongated blocks

15 and 16 sandwiched between the beams adjacent the ends of the latter. The beams may be secured to the blocks by any suitable means, as by welding, for example. The end of the car holder including block 15 may be termed the forward end of the car holder. Block 15 has an upwardly and forwardly inclined surface 15a, and a transversely extend ing opening 17 snugly supporting a shaft 18, which shaft has reduced in diameter end portions 18a supporting respectively a pair of rollers 19 by means of roller bearing assemblies 20 (FIG. 8). Roller bearing assembly 20, which engages shaft portion 18a and inner cylindrical surface 19a of the roller, is held between an annular shoulder 18b on the shaft and a retaining ring 21 which is held in an annular groove 19b opening into surface 19a of the roller. Nuts 22 threadingly engageable with opposite ends of shaft 18 engage rings 21 for retaining rollers 19 on the shaft.

A block 16 at the opposite or rear end of the car holder mounts a pair of rollers 23. The mounting for these rollers is identical to the construction for mounting rollers 19, and, therefore, will not be described again. Block 16 includes an upwardly and rearwardly inclined face 16a as best seen in FIGS. 5 and 6.

An arm 25 comprising identical spaced plates 25a. and 25b has one end thereof pivotally mounted on a pin 26 which has opposite ends thereof secured in suitable apertures in

beams

12 and 14 intermediate the lengths of the latter. Plates 25a and 25b are secured together in spaced relation by means of a spacer bar 27. A roller 28 is rotatably mounted on a pin 29 by means of a bushing 30, which pin has its opposite ends secured in openings in the corresponding ends of plates 25a, 25b remote from pivot 26. As will be explained hereinbelow, roller 28 is adapted to engage a railway car axle.

Plates 25a, 25b have short extensions at their lower ends supporting a pin 31 which in turn supports a clevis member 32. A rod 34 has one end thereof threadingly secured to the bight portion of clevis 32. The other end of rod 34 is freely slidable through an opening in a member 35 which is fixed between

beams

12 and 14 of the car holder. A nut 36 is threadingly engaged on the end of the rod 34 adjacent clevis 32. A spring 37 encircles a portion of rod 34 and has its opposite ends in engagement with nut 36 and member 35 for constantly urging arm 25 in a clockwise direction as seen in FIGS. 5 and 6. Rod 34 swings through a limited are during swinging of arm 25, and for this reason the opening in member 35 is slightly oversized to accommodate swinging movement of rod 34.

A brace 40 has one end thereof pivotally mounted on a pin 41, which pin has opposite ends thereof secured in suitable openings in arm plates 25a, 25b. Brace 40 has a planar undersurface 40a adapted for rolling engagement on a roller 42 rotatably mounted on a pin 43 having opposite ends thereof secured in suitable apertures in

beams

12 and 14. As will be apparent from FIGS. 5 and 6, roller 42 supports the free end of brace 40 during movement of arm 25 between its vertical position illustrated in FIG. 5 and its horizontal position illustrated in FIG. 6.

A stop pad 45 is secured to inclined face 16a of rear block 16. The free end of brace 40 is adapted to abut stop 45 as arm 25 is swung upwardly under the influence of spring 37 thereby to limit swinging movement of arm 25 in a clockwise position (as seen in FIGS. 5 and 6) and to cooperate with spring 37 for holding the arm in its vertical position.

As 'best seen in FIGS. 5-7, forward block 15 has a forwardly extending projection 15b provided with a transversely extending opening 47. A bent plate 48 is secured to block 15 beneath projection 15a by means of fasteners 49, which plate supports by beans of fasteners 50 a magnet 51.

In like manner, rear block 16 has a rearwardly extending projection 16b having a transversely extending opening 53 therein. A bent plate 54 is secured to block 16 beneath projection 16b by means of fasteners 55. A magnet 56 is secured to the underside of plate 55 by fasteners 57. The purpose of the magnets 51, 56 carried by car holder 10 will be referred to hereinbelow.

Foot operated releasable means are provided for holding arm 25 and brace 40 in substantially horizontal or collapsed disposition as illustrated in FIG. 6. This releasable means includes a bent bracket 60 having a sleeve 61 secured thereto, which sleeve rotatably receives a pin 62 having opposite ends thereof secured in suitable bores in

beams

12 and 14. A spring 63 is received in a blind bore provided in block 15 and opening in face 150: thereof, which spring engages bracket 60 thereby constantly urging the latter to swing in a clockwise direction (FIGS. 5 and 6) about pin 62. Swinging movement of bracket 60 in this direction is limited by engagement of a foot portion 60a thereof with the upper surface of an elongated plate 65 which is secured to the undersides of

beams

12 and 14 along substantially the entire length of the latter. A foot plate 67 is secured to the upper end of bracket 60 as by welding, which plate 67 includes a notch 68 at one end thereof (FIG. 7). Notch 68 defines ear portions 680 and 68b. Notch 68 is adapted to receive roller 28 and ears 68a, 68b are adapted to engage respective projections 69a and 69b (FIG. 9) formed on the free end of arm plates 25a, 25b for holding the arm in the position illustrated in FIG. 6, i.e. the collapsed position. It will be apparent that the foot operated releasable means automatically engages the projections on the arm during lowering of the latter, as smooth curved surfaces 70 on the arm plate engage the ends of ears 68a, 68b thereby swinging plate 67 in a counterclockwise direction (FIGS. 5 and 6) about pin 62 until the ears are allowed to snap over projections 69a, 69b on the arm. Stepping on plate 67 causes the same and bracket 60 to swing about pin 62 thereby releasing arm 25 so that the latter may be erected under the influence of spring 37.

As mentioned above, car holders 10 are mounted between rails of track in parallel relation with the latter for movement in either direction along a rectilinear path parallel to the direction of car movement on the track rails. Referring now to FIGS. 2 and 8, a trackway consisting of parallel, spaced

channels

74 and 75 is mounted on railway ties 76 which support the rails of a track section, the inside head surface of one of the rails being indicated by line 77 in FIG. 2. It will be understood that the entire railway car holder assembly is symmetrical about railway track center line 78 shown in FIGS. 1 and 2.

Channels

74 and 75 are secured on alternate ties 76 by means of angles 79 which are secured to the channels and mounted on the ties by means of suitable fasteners 80.

Channels

74 and 75 are secured to the other ties by means of bars 82 fastened to the ties by means of fasteners 83', the bar being secured to the channels as by welding, for example.

As best seen in FIG. 8, the rollers of the car holder are confined between the

channels

74 and 75, the rollers being adapted to roll on the upper surfaces of the lower flanges of the channels.

Channels

74 and 75 are substantially greater in length than the length of the car holder to permit rolling movement of the latter along the channels. In the embodiment of the invention shown for purposes of illustration wherein the car holder has an over-all length of almost 8 feet, the channels have a length permitting a 6 /2-foot stroke for the car holder. As will become apparent below, the side-by-side mounted car holders are connected with cushioning means for cushioning coupling shocks received by the car holders.

A clevis 85 (FIGS. 2 and 4) is secured to block 15 of the car holder by means of a pin 86 which is received in aperture 47 of projection 15b. A rod 87 has one end thereof secured to clevis 85 and the other end thereof se cured to a clevis 88 (FIG. 1) Clevis 88 is pivotally secured to one end of a cross link or equalizer bar 90 by means of a pin 91. Cross link 90 is pivotally secured at its midpoint between a pair of spaced cross arms 92 at the midpoints of the latter by means of a pin 93.

A long travel cushioning mechanism is mounted between the rails of track just forwardly of the pair of side-by-side mounted car holders 10. The cushioning mechanism includes a plurality of parallel, elongated cushioning devices which extend longitudinally of the rails in laterally spaced relation. In the embodiment of the invention shown for purposes of illustration, five cushioning devices are provided, each cushioning device being indicated generally by numeral 95. As all cushioning devices are of identical construction, only one device will be described in detail.

Now referring to FIGS. 1 and 3, cushioning device 95 includes a cylinder or tube 96 having one end thereof secured to a plate 97 which extends laterally between the rails of track. Plate 97 is secured to a horizontally disposed plate 98 which is mounted on a reinforced concrete footing 99 by means of a number of anchor bolts 100. The other end of the tube 96 is secured between the upper surface of a horizontally disposed plate 102 and the undersurface of a horizontal portion of a bent plate 103. Sleeve 96 may be secured to plates 102, 103 by suitable fasteners or by welding. Plate 102 is secured to a reinforced concrete footing 104 by means of sets of anchor bolts 105 and 106. Anchor bolts 106 are also used to secure plates 102 and 103 together. A rod 103 is concentrically disposed within tube 96 and has one end thereof freely slidable in an aperture 109 formed in plate 97. The other end of rod 108' is threaded and mounts a piston 110, the piston being held to rod 108 by means of a nut 111. A coil spring 112 is retained within tube 96 around rod 108, which spring has one end thereof abutting plate 97 and the other end thereof abutting piston 110. Manifestly, spring 112 restrains movement of rod 108 to the right as seen in FIGS. 1 and 3.

The ends of rods 108 extend between cross arm plates 92 and are secured to the latter by means of respective pins 114. It should be apparent that cushioning devices 95 allow cushioned long travel movement of the car ho1ders in a direction from left to right as seen in FIGS. 2 and 4 so as to adapt the assembly to absorb coupling shocks.

In practice, the railway car holder assembly of this invention is mounted between rails of a track section having a slight grade or slope, this slope being upwardly and to the left with reference to FIGS. 3 and 4. A railway car is switched onto this track section and rolls along the same until the leading axle thereof, indicated 115 in FIG. 4, strikes rollers 28 of the car holders. As the axle 115 strikes rollers 28, the car holders are allowed to move to the right, as seen in FIGS. 2 and 4, in a cushioned manner by compression of springs 112 of cushion devices 95. Springs 112 are of suflicient strength so that the car holders are returned to almost the position they occupy when not engaged by railway cars.

In the embodiment of the invention shown for purposes of illustration, springs 112 are compressed 3 inches when holding 12 average railway freight cars on a 2% grade. As subsequent cars are coupled to the railway car having axle 115 engaged by rollers 28, the car holders give or roll to the right (as seen in the drawings) compressing the springs 112 and absorbing or cushioning the coupling shocks transferred to the car holders. Of course the railway car holder assembly also cushions the coupling shocks when received when a switch engine or the like is coupled with the cars being held by the car holders.

As noted in FIGS. 1 and 3, a plurality of vertically ex tending rails 118 are embedded in footing 99, which rails have flanges abutting a side edge of plate 98. These rails support the fixed parts of the cushioning devices against longitudinal movement thereby reducing the shear stresses developed in the anchor bolts during operation of the cushioning devices.

It will be apparent from FIG. 4 that the car holders permit movement of a railway car from right to left as seen in this figure. The axles of the car engage rollers 28 and thereby swing arms 25 in a counterclockwise directionto allow passage of the car. As soon as a rail axle passes rollers 28, arms 25 are immediately erected or returned to the vertical position by means of springs 37. Accordingly, when a railway car which has just passed the car holders from right to left as seen in FIG. 4, returns down the graded track, the arms of the car holders will be in a position to engage the axle for holding the car on the graded track section. Subsequent cars may then be coupled to this car from either direction. As noted in FIG. 4, the height of arms 25 is such that the center line of rollers 28 is slightly above the center line of rail axle 115. This constructional feature prevents axle 115 from jumping over rollers 28 when the axle engages the rollers from right to left as seen in FIG. 4.

When it is not desired to use the railway car holder assembly of this invention, arms 25 of the car holders are collapsed and held in their collapsed position by means of foot operated plates 67. Arms 25 may be quickly and easily erected by depressing plates 67 by a persons foot.

It should be apparent that by reason of the cushioning devices connected with the car holders for cushioning movement of the latter, substantial coupling shocks may be received by the car holders without damaging the latter or the railway car truck assembly having the axle thereof engaged by the car holders. It should be noted that as rollers 28 engage the railway car axle, e.g. axle 115, at two places near respective ends of the latter, the bending movements in the axle are kept to a minimum. Further, as rollers 28 of the car holders engage the axle at two places equidistantly spaced from the car center line, there is no tendency of the car holders to cock or rotate the railway car truck assembly and derail the latter. Further, it should be noted that as the car holders are pivotally secured to cross link or equalizer bar which is pivotally secured at its midpoint to the cushioning device, equal loads are taken by both car holders in arresting movement of a railway car.

During reciprocal movement of the car holders in the trackways defined by

channels

74 and 75, magnets 51, 56 carried by the car holders act to clear metallic debris from the trackways thereby minimizing the possibility of jamming or sticking of the car holders in respective trackways.

While the invention has been shown but in one form, it

will be obvious to those skilled in the art that it is not to be so limited. On the other hand, this invention is susceptible of various forms and modifications wtihout departing from the spirit and scope of the appended claims.

I claim:

1. A railway car holder assembly comprising, a car holder having collapsible means including a member adapted to be engaged by a railway car axle for acting as a stop against movement of a car in one direction thereof and for permitting movement of the car in an opposite direction, track means mounting said car holder adjacent a rail for movement in either direction along a rectilinear path parallel to the direction of car movement, anchor means in spaced relation with said car holder and fixedly mounted with respect to said rail, cushioning means connected to said car holder and said anchor means for cushioning movement of the former during its movement in a direction corresponding to said one direction of the car, erecting and collapsing movement of said car holder being independent of said cushioning means.

2. A railway car holder assembly of the type adapted to be mounted between rails of track for holding one or more cars on the latter, said assembly comprising, a pair of spaced car holders extending longitudinally of said rails between the same, each of said car holders having collapsible means including a member adapted to be engaged by a railway car axle for acting as a stop against movement of a car in one direction thereof and for permitting movement of the car in an opposite direction, separate track means mounting each of said car holders for movement in either direction along a rectilinear path parallel to the direction of car movement along said rails, anchor means fixedly secured in spaced relation with said car holders, and long travel cushioning means connected to said anchor means and to both of said car holders for cushioning movement of the latter in a direction corresponding to said one direction of the car, erecting and collapsing movement of said car holders being independent of said cushioning means, whereby coupling shocks received by the car holders are largely absorbed by the cushioning means.

3. A railway car holder assembly of the type adapted to be mounted between rails of track for holding one or more cars on the latter, said assembly comprising, a pair of juxtaposed car holders extending longitudinally of said rails between the same, each of said car holders having collapsible means including a member adapted to be engaged by a railway car axle for acting as a stop against movement of a car in one direction thereof and for permitting movement of the car in an opposite direction, separate track means mounting each of said car holders for movement in either direction along a rectilinear path parallel to the direction of car movement along said rails, equalizer bar means pivotally secured to corresponding ends of the car holders so that the latter receive equal coupling shocks from a railway car axle engaged thereby, anchor means fixedly secured in spaced relation with said car holders, and long travel cushioning means connected to said anchor means and to said equalizer bar means for cushioning movement of the car holders in a direction corresponding to said one direction of the car, erecting and collapsing movement of said car holders being independent of said cushioning means, whereby coupling shocks received by the car holders are largely absorbed by the cushioning means.

4. A railway car holder assembly of the type adapted to be mounted between rails of track for holding one or more cars on the latter, said assembly comprising, a pair of juxtaposed car holders extending longitudinally of said rails between the same, each of said car holders having collapsible means including a member adapted to be engaged by a railway car axle for acting as a stop against movement of a car in one direction thereof and for permitting movement of the car in an opposite direction, separate track means mounting each of said car holders for movement in either direction along a rectilinear path parallel to the direction of car movement along said rails, a horizontally disposed cross link pivotally secured at the opposite ends to corresponding ends of said car holders, a horizontally disposed cross arm pivotally secured at its midpoint to the midpoint of said cross link, a plurality of elongated cushioning devices extending in laterally spaced relation longitudinally of said rails between the latter, each of said cushioning devices including relatively movable first and second parts interconnected by spring means, anchor means fixedly mounting each of said first parts in place, each of said second parts being secured to said cross arm thereby to cushion movement of the car holders in a direction corresponding to said one direction of the car, erecting and collapsing movement of said car holders being independent of said cushioning devices, whereby coupling shocks received by the car holders are largely absorbed by said cushioning devices.

5. The railway car holder assembly according to claim 4 wherein each of said first parts includes a tube and wherein each of said second parts includes a rod concentrically disposed within the associated tube and spring means.

6. A railway car holder assembly according to claim 4 wherein each of said car holders is provided with magnetic pick-up means for clearing metallic particles from the associated track means.

7. A railway car holder assembly of the type adapted to be mounted between rails of track for holding one or more cars on the latter, said car holder comprising, beam means disposed between said rails and extending in longitudinal relation with the latter, means attached to said beam means for restraining longitudinal movement of the latter in one direction, an arm pivotally secured at one of its ends to said beam means intermediate the ends of the latter for swinging movement in a vertical plane parallel with the beam means, a roller mounted on the other end of said arm, resilient means attached to said arm for urging the latter to swing toward a vertical position thereby to raise said roller so that the latter is positioned to be engaged by a railway car axle, brace means connected with said arm for preventing swinging movement of the latter beyond its vertical position in a direction so as to adapt the car holder to act as a stop against movement of a car in said one direction and to permit movement of the car in an opposite direction, and releasable means for holding said arm in a substantially horizontal position to permit passage of a car in either direction thereof.

8. A railway car holder assembly of the type adapted to be mounted between rails of track for holding one or more cars on the latter, said car holder comprising, beam means disposed between said rails and extending in longi.- tudinal relation with the latter, means attached to said beam means for restraining longitudinal movement of the latter in one direction, an arm pivotally secured at one of its ends to said beam means intermediate the ends of the latter for swinging movement in a vertical plane parallel with the beam means, a roller mounted on the other end of said arm, resilient means attached to said arm for urging the latter to swing toward a vertical position thereby to raise said roller so that the latter is positioned to be engaged by a railway car axle, brace means pivotally secured at one of its ends to said arm adjacent said other end thereof, a stop carried by said beam means, said brace means adapted to have the other end thereof engaged with said stop for preventing swinging movement of said arm beyond its vertical position in a direction so as to adapt the car holder to act as a stop against movement of a car in said one direction and to permit movement of the car in an oppostie direction.

9. The railway car holder assembly according to claim 8 further defined by the provision of releasable means on said beam means for holding said arm in a substantially horizontal position to permit passage of a car in either direction, and means on said beam means for supporting said other end of the brace means during swinging movement of said arm.

References Cited by the Examiner UNITED STATES PATENTS 12/1923 Richey 104-176 12/1958 Howard 104176

Claims

3. A RAILWAY CAR HOLDER ASSEMBLY OF THE TYPE ADAPTED TO BE MOUNTED BETWEEN RAILS OF TRACK FOR HOLDING ONE OR MORE CARS ON THE LATTER, SAID ASSEMBLY COMPRISING, A PAIR OF JUXTAPOSED CAR HOLDERS EXTENDING LONGITUDINALLY OF SAID RAILS BETWEEN THE SAME, EACH OF SAID CAR HOLDERS HAVING COLLAPSIBLE MEANS INCLUDING A MEMBER ADAPTED TO BE ENGAGED BY A RAILWAY CAR AXLE FOR ACTING AS STOP AGAINST MOVEMENT OF A CAR IN ONE DIRECTION THEREOF AND FOR PERMITTING MOVEMENT OF THE CAR IN AN OPPOSITE DIRECTION, SEPARATE TRACK MEANS MOUNTING EACH OF SAID CAR HOLDERS FOR MOVEMENT IN EITHER DIRECTION ALONG A RECTILINEAR PATH PARALLEL TO THE DIRECTION OF CAR MOVEMENT ALONG SAID RAILS, EQUALIZER BAR MEANS PIVOTALLY SECURED TO CORRESPONDING