US3910655A

US3910655A - Constant contact side bearing

Info

Publication number: US3910655A
Application number: US456540A
Authority: US
Inventors: Donald Willison; Hans B Weber; Joseph S Deucher
Original assignee: Midland Ross Corp
Current assignee: Midland Ross Corp; National Casting Inc
Priority date: 1974-04-01
Filing date: 1974-04-01
Publication date: 1975-10-07
Anticipated expiration: 1992-10-07
Also published as: GB1472010A; AU7951775A; JPS5345563B2; GB1472009A; JPS50149005A; AR210075A1; BR7501871A; IN144186B; ZA751915B; CA1026407A

Abstract

A constant contact railway vehicle side bearing utilizes an elastomeric block received within a housing and has a cap member supported on the block and interlocked therewith to prevent displacement or separation therefrom in service. The bearing housing may be that of a type presently in use on railway vehicles. The block has a configuration such that when the bearing is applied to a railway vehicle the block is placed under predetermined compression and its base is held tightly against displacement relative to the housing.

Description

United States Patent 1191 Willison et al.

[ Oct. 7, 1975 CONSTANT CONTACT SIDE BEARING [73] Assignee: Midland-Ross Corporation,

Cleveland, Ohio 22 Filed: Apr. 1, 1974 [21 Appl. No.: 456,540

Cope 308/138 10/1973 Dwyer 308/138 X Primary Examiner-M. Henson Wood, .lr. Assistant ExaminerMichael Mar Attorney, Agent, or Firm-Henry Kozak [57] ABSTRACT A constant contact railway vehicle side bearing utilizes an elastomeric block received within a housing and has a cap member supported on the block and in- [52 U.S. (:1 308/138; 105/199 CB terleeked therewith to Prevent displacement or p 51 Int. c1. B61F 5/14 ration therefrom in service The bearing housing y [58] Field of S r h 308/138, 73; 105/199 CB; be that of a type presently in use on railway vehicles. 267/3 The block has a configuration such that when the bearing is applied to a railway vehicle the block is [56] R f r n Cit d placed under predetermined compression andits base UNITED STATES PATENTS is held tightly against displacement relative to the 2,363,260 11/1944 Peskin 308/73 housmg' 2,913,288 11/1959 Blattner 308/138 17 Claims, 14 Drawing Figures 1\ k '1'.- Q1 3w i 1 1 J 52 00 9, b e Q: 3 L

fizz 0 4 32 324 U.S. Patent Oct. 7,1975 Sheet 1 of3 3,910,655

w i C) Z6 22 26 Sheet 2 of 3 3,910,655

US. Patent Oct. 7,1975

CONSTANT CONTACT SIDE BEARING BACKGROUND oF Tl-lE INvENTToN The invention relates to a sidebearing that is interposed between the bolster of a railway car truck and a tioned side bearings a car truck with worn wheels will begin to hunt as the truck approaches a critical speed of travel. At the critical speed the hunting of the truck may become so violent as to cause the truck to derail.

SUMMARY OF THE INVENTION The present invention is directed to an improved resilient side bearing for railway vehicles and more particularly to the type which remains in constant contact with the car truck bolster and the car body bolster. The bearing comprises a box-like housing mounted on the car truck bolster, an elastomeric block of suitable hardness carried within the housing and a cap supported on the block and interlocked therewith, the cap being in constant engagement with the underside of the body bolster. The block is placed under a predetermined amount of initial compression when the bearing is applied to a railway car so that for small swivelling movements of the truck the cap is stationary relative to the body bolster and truck movement is resisted by horizontal deflection of the block, whereas larger angling movement is resisted by the sliding of the cap relative to the-body bolster. This resistance to swivelling of the truck opposes its tendency to hunt as the car approaches a speed which would be critical if the truck were equipped with roller type side bearings. However, this control of hunting by the improved side bearing has the effect of increasing the speed at which hunting may become critical, thus permitting safe operation of trains at higher speeds than is possible with plain friction or roller type side bearings.

Accordingly, it is the main object of this invention to provide an improved railway car truck side bearing of the resilient type that is in constant Contact with the car truck bolster and the car body bolster for controlling hunting of the truck in service.

A more specific object is to provide a side bearing having a box-like housing, an elastomeric block within the housing, and a cap member supported on the block, the cap member and block being interlocked together against separation in service.

=A further object is to provide a resilient side bearing in which an elastomeric block is contained in a box-like housing and is placed under predetermined initial compression when the bearing is applied to a railway vehicle, the block having a configuration such that th'e block is partially confined by portions of the-cap member supported on the block to produce. a force deflection characteristic whereby increased resistance to compression of the block occurs as .the;latter ap=:

proaches its maximum allowable deflection;

Another object isyto provide an improved side bearing of the constant contact type employing an elastomeric block as the cushioning medium and which embodies means for protecting theblock against oversolid compressive forces.

A still further object is to provide a novel resilient side bearing which can utilize existing side bearing housings to make possible an efficient as well as economical device.

Other objects and advantages of the invention will become apparent from the following description taken in Conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a plan view of a railway car truck having side bearings constructed in accordance with the present invention.

FIG. 2 is a fragmentary elevational view partly in section showing a pair of side bearings embodying the invention installed between a car truck bolster and a car body bolster.

FIG. 3 is a side elevational view of a side bearing embodying the invention, the bearing being shown in free or uncompressed condition.

FIG. 4 is a vertical longitudinal sectional view of the side bearing shown in FIG. 3, the left half showing the position of the parts at the free height of the bearing and the right half showing the assembled height of the bearing after it has been installed in a railway car.

FIG. 5 is a plan view partly in horizontal section taken along line 55 of the side bearing shown in FIG. 3.

FIG. 6 is an end view of the side bearing.

. FIG. 7 is a transverse sectional view taken along line 77 of FIG. 5, the elastomeric block being shown in end elevation.

FIG. 8 is an end view of the side bearing cap.

FIG. 9 is an end view of the elastomeric block.

FIG. l0-is a side elevation of the side bearing cap.

FIG. 11 is a side elevation of the elastomeric block.

FIG. 12 is a bottom plan view of the side bearing cap.

FIG. 13 is a top plan view of the elastomeric block.

FIG. 14 is a ,view similar to FIG. 7 but showing, the elastomeric block compressed to the extent that the side bearing cap is in engagement with the top of the side bearing housing.

DESCRIPTION OF PREFERRED EMBODIMENT In FIGS. 1 and 2 of the drawing there is showna car truck of conventional design comprising aside frame 10, a bolster l2 and a pair of wheel axles 14. It will be understood that another identical side frame 10 (not shown) is disposed at the right hand side of FIG. 1 and is connected to the bolster and wheel axles in the same manner as the side frame shown. The bolster 12 is resiliently supported on the central portion 16 of the side frame by means of springs 18. Pivotally mounted on truck bolster 12 by means of the usual center bearing 20 is the car body bolster 22 (FIG. .2) to permit swivelling of the truck relative to the car body.

Mounted on the-truck bolster 12 and secured thereto are resilient side bearings 24 embodying the invention. Each side bearing is located between center plate 20 and side frame 10 and is in engagement with the underside of a rigid bearing member 26 secured to the underside of body bolster 22. Constant contact occurs between each side bearing 24 and member 26 so that a predetermined amount of frictional resistance created thereby serves to oppose swivelling or angling of the truck, as will be hereinafter set forth.

Side bearing 24 comprises an elongated box-like casing or housing 30 having a flat base 32 and a pair of vertical side walls 34 joined to the base. The ends of walls 34 are turned inward to form transverse end wall portions 36. The opposing inner ends of wall portions 36 are spaced apart to form an opening 38 at each end of the housing. At each end of base 32 there is provided a hole 40 for receiving suitable means such as a rivet or bolt for securing the housing to the truck bolster. Housing 30 is of a type presently in common use with roller side bearings. This housing base 32 has a concavely curved top surface 32a on which the roller of such a side bearing rolls. While housing 30 itself is old in the art, its ready availability on railway cars now in service makes it highly economical to use in conjunction with the present invention.

Within housing 30 and supported on base 32 is block which may be made of elastomeric material such as rubber or polyurethane and which is of suitable hardness and resiliency to provide the necessary loaddeflection characteristics. Block 50 in its uncompressed state is of generally trapezoidal configuration 1 in both longitudinal and transverse vertical cross section. In its uncompressed or free condition (FIGS. 9 and l l) the block has a flat bottom surface 50a. Its longitudinal side surfaces 50b and end surfaces 500 slant inwardly from the base to the top so that the upper end of the block is of smaller area than the base. At its midpoint the top side of the block is relieved across its en tire width in the form of a V-shaped recess 50r. Supported on the block is a follower or cap member having a horizontal top wall 61 which at its midpoint has a transversely extending depending ridge-like projection 62 for positioning the member lengthwise of the block. Projection 62 has a pair of downwardly converging surfaces 62r which have the same slope as the V- shaped surfaces of recess 50r and are adapted to engage therewith to position the cap member relative to the block. Projection 62 has a flat underside 62f that extends between the lower extremities of surfaces 62r. At the end of the cap member are depending legs 64 which are T-shaped in horizontal cross section and extend into housing 30. The opposing inner faces 64a of legs 64 converge in a direction upwardly of the cap for a purpose which will be hereinafter explained. A substantial clearance between legs 64 and the adjacent walls of the housing is provided as at 66 in a lengthwise direction and as at 68a and 68b in a transverse direction. This clearance is to avoid engagement between the cap and the opposing inner

vertical surfaces

34a, 36a, and 36b of the housing as the cap moves relative to the housing in service in response to swivelling of the truck. The cap is formed with longitudinal side flanges 70 depending from top wall 61, which flanges merge with projection 62 and legs 64 to provide a pair of recesses 72 on the underside of the cap for receiving the upper end of the block. The undersides of flanges 70 are coplanar with underside 62f of projection 62. At each outer end of recess 72, there is a pocket portion 74 formed by a transverse wall portion 74a which commences at line f on leg inner side 64a and slants upwardly toward the adjacent end of the cap and is joined with the underside of top wall 61 by a concavely rounded portion 74b. Wall portion 74a provides an abutment or shoulder for use in interlocking the cap with block 50, as will be hereinafter described.

At each upper edge of block 50 is an ear or lug 76 which projects outwardly of end surface 500 and has its top side disposed flush with the top surface of the block. Lug 76 is of such configuration that when cap 60 is in assembled relation with the block, each lug is within pocket 74, with its underside 76a in engagement with shoulder 74a to interlock the cap to the block against separation therefrom. It will be observed that each upper end 80 of the block is contoured to fit snugly within recess 72 as seen in FIGS. 3 and 4 to complete the interlock between the cap and block. Block 50 is also provided with ears or positioning lugs 82 projecting outwardly from the lower ends thereof. Lugs 82 are so contoured as to position the block within the housing in a direction lengthwise thereof through engagement with the heads of securement means such as rivets 84 or other fasteners used to secure the housing to the bolster. At the left hand side of FIGS. 3 and 4 securemenet means 86, commercially known as a Huck fastener, has been shown. In this manner the block is properly positioned lengthwise of the housing and is also held against displacement longitudinally thereof.

Assembling of the cap and block is accomplished by positioning the cap over the block in sloped relation thereto so that one of lugs 76 is received within pocket 74 after which the other end of the cap is lowered onto the block so that sloped surface 64a of leg 64 bears against the other of lugs 76 on the block. A downward force is next applied against the last mentioned end of the cap whereby the wedging action of surface 64a forces lug 76 inwardly of the block and along surface 64a. The wedging action continues as the lug reaches recess 72, after which the internal stresses which have been imparted to the block are released and the lug is forced into pocket 74 to interlock the cap with the block against detachment therefrom in both vertical and horizontal directions. The interlocked cap and block may be readily applied to housing 24 to complete the side bearing assembly.

It will be understood that in its free or uncompressed condition the bearing will have a free height as seen in FIG. 3, and in the left side of FIG. 4, cap 60 being interlocked with block 50. Upon application of the bearing to a railway vehicle between the truck bolster l2 and car body bolster 22 as in FIG. 2, block 50 is compressed a predetermined amount by the weight of the car body. This amount is indicated by the dimension x in FIG. 4. The free height less the dimension x represents the assembled height of the bearing, as shown in FIGS. 4, 6 and 7. From the assembled height of the bearing, cap 60 has a downward travel of distance y before its lateral extensions 61a of top wall 61 engage the opposing top surfaces of housing walls 34, as in FIG. 14. Distance y is preferably less than distance x so that, as the car body rocks in service, cap 60 will always remain in contact with bearing member 26 on the body bolster. It will be observed from the right half of FIG. 4 that the end surface 500 has bulged outwardly, its upper portion being in contact with surface 64a. This partial restriction of expansion of the block 50 by the 1 cap provide a force-deflection characteristic such that a rapid increase in compressive load force occurs as the block is compressed further from the FIG..4 position.

It will also be observed thatat the assembled height of the bearing, sides 50b of block 50 are convexly bulged v as in FIGS. 6 and 7 but very little engagement, if any, will occur between sides 50b and the adjacenthousing walls 34.

Referring to FIG. 9 which shows block 50 in its uncompressed or free state, it will be noted that the base of the block is formed with outwardly projecting toe portions 51 along its lower longitudinal edges. Toe portions 51 are for the purpose of positioning and holding the block transversely within housing 24 through engagement with inner surfaces 34a of side walls 34.

Referring to FIG. 14 it will be seen that partial confinement of the longitudinal sides 50b of block 50 by side walls 34 occurs when the bearing is compressed to over-solid position shown. Thus the engagement between top wall extensions 61a of the cap and the upper surfaces of walls 34 serves to protect the elastomeric material of the block from possible damage due to overcompression thereof. However, in the event of a failure of the elastomer, cap 60 will contact the housing as shown and the bearing will function in the same manner as a conventional friction type side bearing. In such case a clearance will exist between the top face of the cap and body bolster bearing 26, when the body bolster is horizontal relative to the truck bolster.

The functioning of the side bearing in service is such that dual control of the swivelling or hunting of a car truck relative to its car body is provided. Small angling movements of the truck are controlled by the deflection of block 50 horizontally in shear caused by relative movement between cap 60 and housing 24, while larger angling movements are resisted by the sliding action of cap 60 relative to body bolster bearing member 26. The static frictional force existing between cap 60 and member 26 is greater than the resistance of the block to horizontal deflection in shear for a small degree of swivelling of the truck and therefore no relative movement occurs between cap 60 and member 26 during such swivelling of the truck. In this connection it is to be noted that cap 60 in its assembled position with block 50 is in tight fitting engagement therewith. Thus, tight contact exists between side flanges 70 of the cap and sides 50b, between surfaces 62r and 50r, and between surfaces 64a and 50c to assure that the cap will cause flexing of the block during the aforementioned small degree of truck swivelling. In addition, as aforementioned, the bottom of the block is held in fixed relation to the housing by toe portions 51 and lugs 82. However, whenever the resistance of the block to horizontal deflection in shear exceeds the force of static friction between cap 60 and member 26, as when the car travels along a curve, sliding of the cap relative to the member will result. From the above it will be seen that the swivelling movements of the truck are under continuous control .and tests have indicated that the speed at which hunting becomes serious has been increased approximately -15 miles per hour over that for a similar car truck equipped with roller or plain friction type side bearings.

It is to be noted that in the operation of the side bearings, deflection and movement thereof in a horizontal direction occur in the absence of any engagement between the cap and housing because of the substantial clearances as at 66, 68a and 68b. This" feature avoids the problem of wear between moving metal parts and the consequent looseness and slack which develop in devices whose etfective operation depends on closeness of fit between its moving parts.

What is claimed is:

1. A resilient side bearing for railway vehicles, comprisinga housing having a base with sidewalls extending upwardly therefrom, a block member of resilient material in said'housing and supported on said base, a cap member positioned on said block member for transmitting vertical loads thereto, said cap and block members having interlocking lugand pocket means for securing said cap member to said block member against detachment therefrom in vertical and horizontal directions, and means on said cap member adapted for wedging engagement with said block member, during securement of the members, to deform said block member whereby said lug and pocket means are forced into interlocking engagement.

2. A resilient side bearing as set forth in claim 1 in which:

said interlocking means comprises a pair of integral lugs on one of said members and pockets for receiving said lugs on the other of said members.

3. A resilient side bearing as set forth in claim 1 in which:

said interlocking means comprises a pair of lugs on said block member and pockets in said cap member for receiving said lugs.

4. A resilient side bearing as set forth in claim 1 in which:

said block member has a V-shaped central groove extending transversely across its top and said cap member has a depending projection received in said groove, said projection having faces sloped complementary to the surface in said groove and being in engagement therewith.

5. A resilient side bearing as set forth in claim 2 in which said block member has outwardly projecting lugs at lower ends thereof adapted for engagement with associated securement means in said housing for positioning the block member longitudinally of the housing.

6. A resilient side bearing as set forth in claim 3 in which said cap member has stop means for engagement with the upper ends of said top walls to limit compression of said block.

7. A resilient side bearing as set forth in claim 3 in which said cap member has a pair of recesses in its underside for receiving complementarily shaped upper ends of said block member, said pockets being disposed adjacent the outer ends of said recesses.

8. A resilient side bearing as set forth in claim 1 in which said cap member has depending legs which extend into said housing, and has sufficient clearance between said legs and the adjacent sidewalls of the housing to allow a predetermined amount of horizontal movement of the cap member with respect to the hous- 9. A resilient side bearing as set forth in claim 8 in which said legs have sloping surfaces engaging portions of the opposed end surfaces of said block member to partially confine the block member against end-wise expansion.

10. A resilient side bearing as set forth in claim 1 in which said block member has a generally trapezoidal configuration in longitudinal vertical cross section.

*1 11. A resilientside bearing as set forth in claim 1 in which said block member has a generally trapezoidal configuration in transverse cross section.

12. A resilient side bearing as set forth in claim 4 in which said block has horizontal top and bottom faces and is of trapezoidal configuration in both transverse and longitudinal cross section. 7

13. A block of resilient material adapted for supporting a cap member of a railway side bearing, said block comprising horizontal base and top portions, end surfaces of the block converging in a direction upwardly from said base portion, said top portion having a V- shaped central groove extending thereacross for engagement with a depending projection on an associated cap member for positioning the cap member lengthwise of the block, and a projecting lug at each end of the block adjacent said top portion adapted for interlocking engagement with a pocket in an associated cap member. j

14. A block of resilient material as set forth in claim 13, which has outwardly projecting lugs at the lower ends thereof adapted for engagement with securement toe portions along its lower longitudinal edges for positioning the block transversely within an associated housing through engagement with the sidewalls of the housing.

17. A resilient side bearing for application between a railway car truck bolster and a car body bolster, said side bearing being compressed to an assembled height when interposed between said truck bolster and body bolster, said side bearing comprising a housing having a base with sidewalls extending upwardly therefrom, a block of resilient material in said housing and supported on said base, said block being held against horizontal displacement relative to said base, a cap member positioned on said block member and movable vertically relative to said base for transmitting vertical loads from said body bolster to the block, said cap and block members having interlocking lug and pocket means for securing said cap member to said block member against detachment therefrom in vertical and horizontal directions, said block member having a configuration such that the amount of vertical travel of said cap member from the free height of said side bearing to said assembled height is greater than the amount of vertical travel of said cap member from said assembled height to the fully compressed height of the side bearing.

Claims

1. A resilient side bearing for railway vehicles, comprising a housing having a base with sidewalls extending upwardly therefrom, a block member of resilient material in said housing and supported on said base, a cap member positioned on said block member for transmitting vertical loads thereto, said cap and block members having interlocking lug and pocket means for securing said cap member to said block member against detachment therefrom in vertical and horizontal directions, and means on said cap member adapted for wedging engagement with said block member, during securement of the members, to deform said block member whereby said lug and pocket means are forced into interlocking engagement.

2. A resilient side bearing as set forth in claim 1 in which: said interlocking means comprises a pair of integral lugs on one of said members and pockets for receiving said lugs on the other of said members.

3. A resilient side bearing as set forth in claim 1 in which: said interlocking means comprises a pair of lugs on said block member and pockets in said cap member for receiving said lugs.

4. A resilient side bearing as set forth in claim 1 in which: said block member has a V-shaped central groove extending transversely across its top And said cap member has a depending projection received in said groove, said projection having faces sloped complementary to the surface in said groove and being in engagement therewith.

8. A resilient side bearing as set forth in claim 1 in which said cap member has depending legs which extend into said housing, and has sufficient clearance between said legs and the adjacent sidewalls of the housing to allow a predetermined amount of horizontal movement of the cap member with respect to the housing.

9. A resilient side bearing as set forth in claim 8 in which said legs have sloping surfaces engaging portions of the opposed end surfaces of said block member to partially confine the block member against end-wise expansion.

11. A resilient side bearing as set forth in claim 1 in which said block member has a generally trapezoidal configuration in transverse cross section.

12. A resilient side bearing as set forth in claim 4 in which said block has horizontal top and bottom faces and is of trapezoidal configuration in both transverse and longitudinal cross section.

13. A block of resilient material adapted for supporting a cap member of a railway side bearing, said block comprising horizontal base and top portions, end surfaces of the block converging in a direction upwardly from said base portion, said top portion having a V-shaped central groove extending thereacross for engagement with a depending projection on an associated cap member for positioning the cap member lengthwise of the block, and a projecting lug at each end of the block adjacent said top portion adapted for interlocking engagement with a pocket in an associated cap member.

14. A block of resilient material as set forth in claim 13, which has outwardly projecting lugs at the lower ends thereof adapted for engagement with securement means of an associated side bearing housing to position the block longitudinally of the housing.

15. A block of resilient material as set forth in claim 11 in which the side surfaces of the block converge in a direction upwardly from said base portion.

16. A block of resilient material as set forth in claim 14 in which said base portion has outwardly projecting toe portions along its lower longitudinal edges for positioning the block transversely within an associated housing through engagement with the sidewalls of the housing.