US2238772A

US2238772A - Railway braking apparatus

Info

Publication number: US2238772A
Application number: US280369A
Authority: US
Inventors: Harold C Clausen
Original assignee: Union Switch and Signal Inc
Current assignee: Hitachi Rail STS USA Inc
Priority date: 1939-06-21
Filing date: 1939-06-21
Publication date: 1941-04-15
Anticipated expiration: 1958-04-15

Description

April 15, 1941. H. c. CLAUSE'N RAILWAY BRAKING APPARATUS Filed June 21, 1939 3 Sheets-Sheet 1 4 mwwm E wmw April 15, 1941. H CLAUSEN 2,238,772

RAILWAY BRAKING APPARATUS INVENTOR Harold C. Clausen.

. fijz'llwz HIS ATTORNEY April 15, 1941. c CLAUSEN 2,238,772

RAILWAY BRAKING APPARATUS Filed June 21, 1959 '3 Sheets-Sheet s INVENTOR Harold C. Ulausezz.

HZ 5". A'ITORN EY Patented Apr. 15, 1941 RAILWAY BRAKING APPARATUS Harold C. Clausen, Wilkinsburg, Pa., assignor to The Union Switch & Signal Company, Swissvale, Pa", a corporation of Pennsylvania Application June 21, 1939, Serial No. 280,369

9 Claims.

My invention relates to railway braking apparatus, and particularly to that class of braking apparatus known as car retarders. More particularly, my present invention relates to car retarders of the type in which the braking bars exert on-each car an amount of retardation which is proportional to the weight of the car.

One object of my invention is to provide a car retarder of the type described in which no part of the weight of the car is transmitted to the retarder through the wheel flanges.

Another object of my invention is to provide a car retarder of the type described which can be readily adjusted.

A further object of my invention is to provide a car retarder of the type described in which a fixed amount of retardation is exerted on all cars above a predetermined weight, whereby excessive strains on the various parts of the apparatus are avoided.

A still further object of my invention is to provide a car retarder of the type described which is inexpensive to manufacture and install, and which at the same time is highly eificient in operation.

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

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

Referring to the drawings, Fig. 1 is a vertical sectional view showing one form of car retarder embodying my invention. Fig. 2 is a side view of the retarder shown in Fig. 1. Fig. 3 is a view similar to Fig. 1, showing a modified form of retarder embodying my invention. Fig. 4 is a side View of the retarder shown in Fig. 3. Fig. 5 is a vertical sectional viewshowing a modification of the retarder illustrated in Figs. 3 and 4. Fig. 6 is a vertical sectional View showing still another form of car retarder embodying my invention. Fig. 7 is a side view of the car retarder shown in Fig. 6. Fig. 8 is a vertical sectional view showing a further form of car retarder embodying my invention. Fig. 9 is a side view of the retarder' shown in Fig. 8. Fig. 10 is a view similar to Fig. 8 showing a modification of the structure illustrated in Fig. 8.

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

Referring first to Figs. 1 and 2, the reference character A designates one track rail of a stretch of railway track over which the wheels of carswhich are to be retarded by means of the braking apparatus embodying my invention are adapted to pass. The rail A is mounted at spaced intervals on cradles I, only one of which is shown in the drawings, and each cradle, in turn, is pivotally attached at its opposite end by means of

pivot pins

2 and 3 to vertically disposed levers 6 and l. The levers 6 and I extend downwardly and outwardly between pairs of upstanding arms 8 formed on a support 9 secured to two adjacent crossties I0, and are provided below their points of attachment with the cradle I with pairs of rollers l I which ride on fiat surfaces [2 provided on the support 9. Each arm 8 is provided at its upper end with a vertical slot [3 which aligns with the corresponding slot in the other arm of the same pair of arms, and these slots slidably receive the ends of the

pivot pins

2 and 3, whereby the rail A is prevented from becoming displaced laterally, but is free to move vertically to a limited distance in response to rotation of the levers, for a purpose which will appear presently. It will be seen, therefore, that each support 9 not only supports the levers 6 and l but also acts as a guide for the cradle I.

The upper end of the lever B carries a braking oar B which extends parallel to the rail A, and the upper end of the lever I similarly carries a braking bar C which likewise extends parallel to the rail A. Each braking bar B comprises, as

' usual, a brake shoe l4 secured to a brake beam [5.

clearance through an opening Ta provided in when no car is passing through the retarder, the

levers 6 and I will be rotated by the spring 22 to positions in which the spacing between the braking bars B and C will be less than the width of car'wheels.

With the retarder constructed in this manner when a car enters the retarder, the wheels W of the car will force the braking bars apart to the positions in which they are shown in Fig. :1, and will thus cause the lever 6 to rotate in a clock- Wise direction about the pivot pin 2, and the lever 1 to rotate in a counterclockwise direction about the pivot pin 3. This rotation of the levers, in turn, will cause the spring 22 to become compressed, and will also act to move the cradle, and hence the rail A upwardly, thereby causing the weight of the car to be transferred to the

pivot pins

2 and 3. Due to the fact that the rollers l I are offset outwardly from the pivot pins, any force which is exerted on the pivot pins will exert a turning moment on the levers in the direction to force the braking bars into frictional engage ment with the side faces of the car wheels, and it will be apparent, therefore, that the braking bars will be urged into engagement with the wheels of the car by a force which is directly proportional to .the weight of the car. The magnitude of this force for any particular weight of car will of course depend partly upon the lever arm ratios which are provided, and partly upon the characteristics of the spring 22, and may be varied by changing either the lever arm ratios or the characteristics of the spring. It should be noted, however, that the spring is not necessary to my invention and may, if desired, be omitted altogether. spring is omitted, the braking bars will still return to their closed positions when no car is in the retarder due to the gravity bias afiforded by the weight of the rail and the cradles.

If it is desired to render the retarder inactive for any reason, this may be done by screwing nut onto the bolt l9 far enough to rotate the levers to positions in which the braking bars will be held out of engagement with car wheels traversing the rail.

Referring now to Figs. 3 and 4, in the modified form of car retarder here illustrated, the

levers

6 and 1 have been replaced by levers 26 and 2'! which terminate at their lower ends at the rollers H, and which are provided between their points of connection with the cradle and the rollers with aligned openings 28 through which a spring bolt 29 passes with some clearance. A nut 30 is adjustably screwed onto the bolt 29 on the left-hand side of the lever 26, as viewed in Fig. 3, and disposed on the bolt on the other side of the lever are a coil spring 3|, a washer 32 and a nut 33. The spring 3| is sufliciently stiff to hold the lever 26 in the position in which it engages the nut 30 when no car is in the retarder, and it will be apparent that the weight of the rail acting through the moment arm which exists between the pivot pin 3 and roller Ill on lever 21 will cause this latter lever to remain in engagement with the head of the bolt. It follows, therefore, that by adjusting the nut 30 to different positions the spacing between the braking bars when no car is in the retarder can be accurately controlled. Furthermore, by proper adjustment of the nut 30 the

levers

26 and 21 can be made to occupy either position in which the spacing between the braking bars is'greater than the width of car wheels, or positions in which this spacing is less than the width of car wheels.

The braking apparatus as shown in Figs. 3 and 4 further comprises two

screws

34 and 35 which are screwed through lugs 36 provided on two of the arms 8 of the support 9, and which cooperate with the

levers

26 and 21 at bosses 3'! which sur- It should also be noted that if the round the outer ends of the openings 28. It will be apparent that by screwing these screws inwardly the levers can be prevented from rotating to the positions in which the braking bars will frictionally engage the wheels of cars passing through the retarder, whereby the retarder can be rendered ineffective to retard cars.

With the retarder constructed as shown in Figs. 3 and 4 the nut 30 will usually be so adjusted that when no car is in the retarder, the

levers

26 and 27 will be rotated to positions in which the spacing between the braking bars is greater than the widths of car wheels, and it will be apparent therefore that with the nut adjusted in this manner, as soon as a car enters the retarder the weight of the car will automatically cause the levers to rotate to the positions in which the braking bars will frictionally engage the opposite side faces of the wheels with a force which is proportional to the weight of the car.

It is somtimes desirable to provide a car retarder which will retard only loaded cars, and with the retarder constructed as shown in Figs. 3 and 4 this result can readily be accomplished by making the spring 3| sufficiently stiff so that it will prevent the levers from rotating to the positions in which the braking bars B and C will engage the car wheels unless the weight of the car exceeds a. predetermined weight which is in excess of the average weight of empty cars. This feature of the retarder shown in Figs. 3 and 4 is an important one.

It should be noted that with the form of the retarder shown in Figs. 3 and 4, since it is necessary to compress the spring 3| to cause the braking bars to move into engagement with the wheels, this spring acts as a bufier to take up a certain amount of shock.

Referring now to Fig. 5, the retarder here shown is similar to that shown in Figs. 2 and 3 except for the fact that the rollers ll instead of resting on the support 9 rest on plates 40 which are slidably mounted in the upper ends of wells 42 formed in the support 9, and which plates are biased to upper positions by means of springs 4| disposed in the wells. The springs 4| are so constructed that they will deflect when and only when a car in excess of a predetermined weight, or a locomotive passes through the retarder, and their function is to prevent excessive stresses from being exerted on the braking apparatus.

Referring next to Figs. 6 and '7, in the form of my invention here shown the levers 6 and I are pivotally attached adjacent their lower ends by means of pivot pins and 5! to a combined lever support and cradle guide 53, and are operatively connected adjacent their upper ends with a cradle 54 to which the rail A is attached, by means of

pins

55 and 56 which extend with clearance through longitudinally extending

slots

51 and 58 provided in the cradle. The ends of the cradle 54 extend into guideways 59 formed in

upstanding arms

60 and 6| provided on the lever support and cradle guide 53, whereby the cradle is free to move vertically but is prevented from moving laterally. The remainder of the structure is similar to that shown in Figs. 1 and 2.

With the structure constructed as shown in Figs. 6 and 7, the levers are biased by the weight of the rail and cradle acting on the moment arms between the two vertically offset pivot pins of the levers, and by the spring 22, to positions in which the spacing between the braking bars is less than the widths of car wheels, and it will be seen, therefore, that when a car wheel enters the retarder, thereby forcing the braking bars apart, the cradle and rail will move upwardly, and will thus cause a torque to be exerted on the levers which torque, in turn, will cause the braking bars to irictionally engage the wheels with a force which is proportional to the weight of the car.

If it is desired to prevent the retarder from retarding cars, this result may be obtained by screwing the nut 20 inwardly to thereby prevent the levers from rotating in response to a downward force exerted on the rail, substantially as described in connection with Fig. 1.

Referring to Figs. 8 and 9, the retarder here shown difiers from that shown in Figs. 6 and 7 in that the levers B and I have been replaced by the

levers

26 and 21 which latter levers are biased apart by a spring 65 disposed on a bolt 56 that extends with clearance through the openings 28 in the levers. A nut 20 is screwed onto the left-hand end of the bolt 68 and serves to limit the position to which the levers are free to rotate in response to the bias of the spring 65. This nut will usually be so adjusted that when the levers occupy the positions which they occupy when no car is passing through the retarder, the braking bars will be spaced apart a distance which is just a little wider than the widths of the wheels. The advantage of this adjustment is that it prevents excessive shock when the car enters the braking apparatus and forces the braking bars into engagement with the wheels.

The structure shown in Figs.8and9alsoincludes two stop screws 61 and 68 screwed through upstanding lugs 59 and IO-provided on the support 53, and cooperating with the lever at one side of the bosses 31. When it is desired to render the retarder inactive, the nut 20 is backed off and these screws are then screwed into engage ment with the levers, to thereby hold the levers in positions in which the braking bars are spaced apart a greater distance than the widths of car wheels.

The operation of the retarder shown in Fig. 8 will be readily understood from the preceding description without further detailed description. It should be noted, however, that by making the spring 65 sufficiently stifi the retarder can be made to operate in such manner that it will only retard cars having a weight in excess of a predetermined weight, in the same manner as with the structure shown in Fig. 3.

Referring now to Fig. 10, the retarder here illustrated is similar to that shown in Fig. 8 with the exception that the bolt 66 shown in Fig. 8 has been replaced by a bolt 15 which is provided at each end with a nut 20, and which is surrounded between the levers 26 and 2'! with two springs 12 and H. These springs abut at one end against the bosses 31 which surround the openings 28 in the levers, and at their opposite ends against

washers

68 and 61, respectively, which latter, in turn, abut against sep

arate adjusting nuts

14 and 13, respectively. With this latter arrangement, it will be seen that by varying the adjustment of the nuts 13 and H the critical weight that a car must have to cause the apparatus to function can be readily only a few forms of railway braking apparatus embodying my invention, it is understood that variouschanges 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. Railway braking apparatus comprising a track rail supported by two pivoted levers in such manner that the weight of a car traversing the rail will exert a torque on the levers tending to move the upper ends of the levers toward the rail, braking bars secured to the upper ends of the levers and movable thereby toward the rail to positions in which the spacing between said braking bars is less than the widths of car wheels, and spring means cooperating with said levers and effective when said braking bars are engaging a vehicle wheel for limiting the torque exerted on said levers by vehicles having a weight in excess of a predetermined weight or wide wheels or both.

'2. Railway braking apparatus comprising a support, a track rail secured to a cradle, pins passing through the ends of said cradle and disposed in vertical slots in said support whereby said rail is free to move vertically through a limited distance but is prevented from moving laterally, two lever pivoted intermediate their ends on said pins and supported at their lower ends on said support in such manner that the weight of a car traversing said rail will exert a torque on said levers which tends to move their upper ends toward the rail, and braking bars secured to the upper ends of said levers for engagement with the wheels of a car traversing said rail.

3. Railway braking apparatus comprising a support, a track rail secured to a cradle, pins passing through the ends of said cradle and disposed in vertical slots in said support whereby said rail is free to move vertically through a limited distance but is prevented from moving laterally, two levers pivoted intermediate their ends on said pins and supported at their lower ends on said support in such manner that the weight of a car traversing said rail will exert a torque on said levers which tends to move their upper ends toward the rail, braking bars secured to the upper ends of said levers for engagement with the wheels of a car traversing said rail, and spring means biasing said levers to positions in which the spacing between said braking bars is less than the widths of car wheels.

4. Railway braking apparatus comprising a support, a track rail secured to a cradle, pins passing through the ends of said cradle and disposed in vertical slots in said support whereby said rail is free to move vertically through a limited distance but is prevented from moving laterally, two levers pivoted intermediate their ends on said pins and supported at their lower ends on said support in such manner that the weight of a car traversing said rail will exert a torque on said levers which tends to move their upper ends toward the rail, braking bars secured to the upper ends of said levers for engagement with the wheels of a car traversing said rail, and means for rotating said levers to and holding them in positions in which said braking bars are out of engagement with the wheels of a car traversing said rail.

5. Railway braking apparatus comprising a support provided with two spaced pairs of upstanding arms each pair of which is provided with aligned vertically extending slots in their upper ends, a cradle provided at its ends with pins slidably mounted in said slots, a rail secured to said cradle, two levers one pivoted intermediate its ends on each of said pins and each provided at its lower end with a roller which rides on said support, said rollers and said pins being .so disposed that the weight of a car on said rail will exert a torque on said levers which tends to rotate their upper ends toward the rail, and two braking bars secured to the upper ends of said levers and movable toward the rail by the levers to positions in which the spacing between them is less than the widths of car wheels.

6. Railway braking apparatus comprising a support provided with two spaced pairs of upstanding arms each pair of which is provided with aligned vertically extending slots in their upper ends, a cradle provided at its ends with pins slidably mounted in said slots, a rail secured to said cradle, two levers one pivoted intermediate its ends on each of said pins and each provided below its pivot point with a roller which rides on said support, said rollers and said pins being so disposed that the weight of a car on said rail will exert a torque on said levers which tends to rotate their upper ends toward the rail, two braking bars secured to the upper ends of said levers and movable toward the rail by the levers to positions in which the spacing between them is less than the widths of car wheels, a bolt pivotally attached to the lower end of one lever and extending with clearance through an opening in the lower end of the other lever, and a nut on said bolt effective when screwed in one direction to rotate the levers to and hold them in positions in which the spacing between said braking bars is greater than the widths of car wheels.

'7. Railway braking apparatus comprising a support provided with two spaced pairs of upstanding arms each pair of which is provided with aligned vertically extending slots in their upper ends, a cradle provided at its ends with pins slidably mounted in said slots, a rail secured to said cradle, two levers one pivoted intermediate its ends on each of said pins and each provided at its lower end with a roller which rides on saidsupport, said rollers and said pins being so disposed that the weight of a car on said rail will exert a torque on said levers which tends to rotate their upper ends toward the rail, two braking bars secured to the upper ends of said levers and movable toward the rail by the levers to positions in which the spacing between them is less than the widths of car wheels, a bolt extending through clearance holes provided in said levers between said pins and said rollers, and a spring mounted on one end of said bolt and biasing said levers to positions in which the spacing between the braking bars is greater than the widths of car wheels.

8. Railway braking apparatus comprising a support provided with two spaced pairs of upstanding arms each pair of which is provided with aligned vertically extending slots in their upper ends, a cradle provided at its ends with pins slidably mounted in said slots, a rail secured to said cradle, two levers one pivoted intermediate its ends on each of said pins and each provided at its lower end with a roller which rides on said support, said rollers and said pins being so disposed that the weight of a car on said rail will exert a torque on said levers which tends to rotate their upper ends toward the rail, two braking bars secured to the upper ends of said levers and movable toward the rail by the levers to positions in which the spacing between them is less than the widths of car wheels, 2. bolt extending through clearance holes provided in said levers between said pins and said rollers, and a spring mounted on one end of said bolt and biasing said levers to positions in which the spacing between the braking bars is greater than the widths of car wheels, the parts being so proportioned that said spring will prevent said levers from rotating except when a car having a weight in excess of a predetermined weight traverses said rail.

9. Railway braking apparatus comprising a cradle, a track rail secured to said cradle, two

levers pivotally attached to said cradle interme diate their ends by means of pivot pins and provided at their lower ends with rollers riding on spring supported means, and at their upper ends with braking bars, the parts being so arranged and so proportioned that the weight of a car on said rail will exert on said levers a torque which urges said braking bars into engagement with the wheels of the car by a force which is proportional to the weight of a car for all cars having a weight less than a predetermined weight but that for all cars above said predetermined weight said spring supported means will yield and limit said torque.

HAROLD C. CLAUSEN.