US2749850A - Friction shock absorbing mechanisms for trucks of railway cars - Google Patents

Friction shock absorbing mechanisms for trucks of railway cars Download PDF

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US2749850A
US2749850A US322882A US32288252A US2749850A US 2749850 A US2749850 A US 2749850A US 322882 A US322882 A US 322882A US 32288252 A US32288252 A US 32288252A US 2749850 A US2749850 A US 2749850A
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bolster
spring
truck
friction
shoes
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US322882A
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Eric G Forssell
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W H MINCR Inc
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W H MINCR Inc
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B61—RAILWAYS
    • B61F—RAIL VEHICLE SUSPENSIONS, e.g. UNDERFRAMES, BOGIES OR ARRANGEMENTS OF WHEEL AXLES; RAIL VEHICLES FOR USE ON TRACKS OF DIFFERENT WIDTH; PREVENTING DERAILING OF RAIL VEHICLES; WHEEL GUARDS, OBSTRUCTION REMOVERS OR THE LIKE FOR RAIL VEHICLES
    • B61F5/00—Constructional details of bogies; Connections between bogies and vehicle underframes; Arrangements or devices for adjusting or allowing self-adjustment of wheel axles or bogies when rounding curves
    • B61F5/02—Arrangements permitting limited transverse relative movements between vehicle underframe or bolster and bogie; Connections between underframes and bogies
    • B61F5/04—Bolster supports or mountings
    • B61F5/12—Bolster supports or mountings incorporating dampers
    • B61F5/122—Bolster supports or mountings incorporating dampers with friction surfaces

Definitions

  • One object of the invention is to provide ina railway car truck, means for frictionallyresisting vertical movernent of the truck bolster, including friction shoes 'carried by the bolster of the truck slidingly engaging friction surfaces provided on the truck side frame, wherein said friction shoes are forced against the friction sur faces by a wedge member which is actuated by springs which also form a part of the spring structure of "the cluster of springs which supports the truck bolster on the truck side frame.
  • a more specific object of the invention is to provide "in a railway car truck structure as set forth 'in the preceding paragraph employing spring clusters, each'composed of a plurality of spring units comprising at least two pairs of units disposed at opposite sides of a central unit, and wherein each unit is composed of an inner coil spring and an outer coil spring, an arrangement whereby the inner coil springs of the two pairs of spring unit's are utilized to urge the wedge member against the shoes.
  • Figure 1 is a broken top plan view of a railway car truck structure, showing a portion of one only of the side frame members of said truck, and the corresponding end of the truck bolster and associated mechanism.
  • Figure 2 is a broken side elevational view of Figure 1.
  • Figure 3 is a vertical sectional view, corresponding substantially to the line 3-3 of Figure 1.
  • Figure 4 is a perspective View of the wedge member of the improved mechanism.
  • Figure 5 is a perspective view of one of the friction shoes. l i
  • the side frame member 10 is in the form of a casting and has top and bottom, horizontal members 11 and 12 connected by vertically disposed sections 13-13.
  • the railway car truck includes two side frame members 10-10, a truck bolster 14, and the usual two clusters of truck springs at opposite sides of the truck, each cluster, as illustrated, comprising five spring units, and each spring unit being composed of an inner spring and an outer spring 16.
  • Each spring cluster is supported on a follower plate 17, resting upon the lower member 12 of the side frame 10 at the corresponding side of the truck.
  • the opposite ends of the bolster 14 are guided between the sections 13-13 of the truck side frames and the bolster is supported by the spring clusters comprising the springs 15 and 16.
  • the truck bolster in turn, supports the body bolster of the railway car, not shown.
  • My improved friction shock absorbing mechanism comprises broadly a pair of friction, shoes A-A at each end of the truck bolster mounted at opposite sides thereof, a wedge member B within the bolster at each end thereof engaging the shoes A-Aand bearing on the upper ends of the inner coil springs 15-15 of the spring units at opposite sides of the corresponding spring cluster, and swivelled friction blocks C-C mounted on the guide portions 18-18 of each side frame.
  • each side frame 10 of the truck with pockets 20-20 at the bolster guide portions 18-18, each pocket opening inwardly towardthe bolster and having a substantially vertically extending concave back wall 21, which presents a spherical bearing surface 22 for the friction block C.
  • the friction blocks C-C of each side frame 10 are seated in the pockets 20-20 and have ball or spherically shaped bearing faces 23-23 on their rear sides engaging the spherical surfaces 22-22 of the pockets 20-20.
  • the front sides of the blocks C-C present flat friction surfaces 24-24 which cooperate with the friction Shoes A-A.
  • the friction shoes A-A and A-A are arranged in pairs at opposite ends of the bolster 14, the shoes of each pair being carried at opposite sides of the bolster.
  • Each shoe A has a flat top end face 124 which slidingly engages a fiat guide surface 25 on the underneath side of the top wall 26 of the bolster 14 at the corresponding side of the latter.
  • Each shoe A project through an opening 27 provided in the corresponding side wall of the bolster and engages the adjacent friction block C.
  • the shoe A is provided with a flat, vertically disposed friction surface 28 on its outer side, which slidingly engages the friction surface 24 of the block C.
  • each shoe A presents a downwardly facing, laterally inwardly extending, inclined wedge face 29, which is engaged by the wedge member B.
  • the wedge member B is in the form of a rectangular plate, which is cut out or slotted at the top at opposite sides thereof, as indicated at 30-30, to accommodate the wedge portions of the shoes A-A.
  • the inner wall member of each of these cut out or slotted portions is inclined, as shown, and provides a wedge face 131 which cooperates with the wedge face 29 of the corresponding shoe A.
  • the member B spans the distance between and overhangs the springs 15-15 and 15-15 at opposite sides of the central spring unit of the cluster and has depending bosses or lugs 31-31 and 31-31 at opposite end portions thereof, which are aligned with and engage the upper ends of the inner coil springs 15-15 and 15-15 of the spring units at opposite sides of the central unit of the five unit spring cluster, the bottom wall of the bolster 14, which wall is indicated by 32, and the usual top spring follower plate of the spring cluster, which plate is indicated by 33, being provided with aligned openings 34 and 35 through which these lugs 31 extend.
  • a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically movable between said guides; of springs supporting said bolster on said truck side frame; friction shoes carried by said bolster; a wedge member within said bolster in wedging engagement with said shoes; a plurality of depending lugs on said wedge member, and a spring for each of said lugs extending therefrom to said truck side frame to urge the wedge member against said shoes, each of said latter springs being disposed concentrically within one of said bolster supporting springs.
  • a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically niov-- able between said guides; of a cluster of springs supporting said bolster on said side frame, said cluster including a central spring unit, and additional spring units arranged at opposite sides of said central unit, each of said spring units including an inner coil spring and an outer coil spring; friction shoes carried by said bolster; and a wedge member in wedging engagement with said shoes, and lugs depending from said wedge member into engagement with said inner coil springs of all of said additional spring units to support the wedge member.
  • a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically movable between said guides; of a cluster of springs supporting said bolster on said side frame, said cluster including a central spring unit, and additional spring units arranged at opposite sides of said central unit, each of said spring units including an inner coil spring and an outer coil spring; friction shoes carried by said bolster; and a wedge member in wedging engagement with said shoes, and lugs depending from said wedge member into engagement with said inner coil springs of all of said additional spring units to support the wedge member, and the bolster being supported on said central spring unit and the outer coil springs of said additional units.
  • a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically movable between said guides; of a cluster of springs supporting said bolster on said side frame, including a central spring unit, and additional spring units arranged at opposite sides of said central unit, each of said spring units including an inner coil spring and an outer coil spring; friction shoes carried by said bolster and slidably engaging said friction surfaces of said guides; and a wedge member in wedging engagement with said shoes, said wedge member having depending lugs thereon said lugs extending into engagement with the inner coil springs only of all of the additional spring units to support the wedge member.
  • a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically movable between said guides; of a cluster of springs supporting said bolster on said side frame including a central spring unit, and additional spring units arranged at opposite sides of said central unit, each of said spring units including an inner coil spring and an outer coil spring; a pair of friction shoes mounted at opposite sides of said bolster, said shoes being laterally movable on said bolster and having sliding engagement with the friction surfaces of said side frame; and a wedge member in wedging engagement with said shoes to spread the same apart, and lugs depending from said wedge member into engagement with said inner coil springs of all of said additional spring units to support the wedge member.
  • a railway car truck including a truck side frame having a bolster receiving opening which is provided with vertically extending interior friction surfaces at opposite sides thereof, the combination with a truck bolster within said opening, said bolster having vertically spaced, top and bottom walls; of a cluster of spring units supported on said side frame beneath said bolster, said cluster including a central unit and an additional pair of units at opposite sides of said central unit, each unit including outer and inner coil springs, said bottom wall of the bolster having a plurality of openings extending therethrough, said openings registering with the inner coils of said pairs of spring units which are at opposite sides of the mechanism; a pair of friction shoes at opposite sides of said bolster having sliding engagement with the friction surfaces of said side frame, said shoes having wedge faces in the inner sides; a wedge plate having wedge faces at opposite sides thereof engaged with the wedge faces of said shoes; pairs of depending bosses on said wedge plate at opposite sides of the center of said plates, said bosses being aligned with and engaging said inner coil springs of said pairs of springs, said

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  • Mechanical Engineering (AREA)
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Description

June 12, 1 E. G. FORSSELL FRICTION SHOCK ABSORBING MECHANISMS FOR TRUCKS OF RAILWAY CARS 2 Sheets-Sheet 1 Filed Nov. 28, 1952 Inven/or: Er ic G.%TSS?Z.
June 12, 1956 E. G. FORSSELL 2,749,850
FRICTION SHOCK ABSORBING MECHANISMS FOR TRUCKS OF RAILWAY CARS 2 Sheets-Sheet 2 Filed Nov. 28, 1952 /5 l 53 1.5 Jig w F2710 GIorsse ZZ.
FRICTION srrocn ABsonBrNG M CHANISMS non 'rnncns or RAILWAY CARS Eric G. Forssell, Kenmore, N. Y., assignor to W. H. Miner, Inc., Chicago, 111., a corporation of Delaware Application November 28, 1952, Serial No. 322,882 6 Claims. or. 105-197 This invention relates to improvements in railway car trucks provided with friction shock absorbing means for snubbing the action of the, truck springs.
One object of the invention is to provide ina railway car truck, means for frictionallyresisting vertical movernent of the truck bolster, including friction shoes 'carried by the bolster of the truck slidingly engaging friction surfaces provided on the truck side frame, wherein said friction shoes are forced against the friction sur faces by a wedge member which is actuated by springs which also form a part of the spring structure of "the cluster of springs which supports the truck bolster on the truck side frame.
A more specific object of the invention is to provide "in a railway car truck structure as set forth 'in the preceding paragraph employing spring clusters, each'composed of a plurality of spring units comprising at least two pairs of units disposed at opposite sides of a central unit, and wherein each unit is composed of an inner coil spring and an outer coil spring, an arrangement whereby the inner coil springs of the two pairs of spring unit's are utilized to urge the wedge member against the shoes.
Other objects of the invention will more clearly appear from the description and claims hereinafter following.
In the accompanying drawings forming a part of this specification, Figure 1 is a broken top plan view of a railway car truck structure, showing a portion of one only of the side frame members of said truck, and the corresponding end of the truck bolster and associated mechanism. u
Figure 2 is a broken side elevational view of Figure 1.
Figure 3 is a vertical sectional view, corresponding substantially to the line 3-3 of Figure 1.
Figure 4 is a perspective View of the wedge member of the improved mechanism.
Figure 5 is a perspective view of one of the friction shoes. l i
In said drawings, indicates one of the side frame members of a railway car truck. The side frame member 10 is in the form of a casting and has top and bottom, horizontal members 11 and 12 connected by vertically disposed sections 13-13. As will be understood by those skilled in this art, the railway car truck includes two side frame members 10-10, a truck bolster 14, and the usual two clusters of truck springs at opposite sides of the truck, each cluster, as illustrated, comprising five spring units, and each spring unit being composed of an inner spring and an outer spring 16. Each spring cluster is supported on a follower plate 17, resting upon the lower member 12 of the side frame 10 at the corresponding side of the truck. The opposite ends of the bolster 14 are guided between the sections 13-13 of the truck side frames and the bolster is supported by the spring clusters comprising the springs 15 and 16. The truck bolster, in turn, supports the body bolster of the railway car, not shown.
As illustrated most clearly in Figures 2 and 3, the
tates Patent "ice sections 13-13 of each side frame are inwardly offset at their upper ends and thus provide vertical guide portions 18-18 at opposite sides of the bolster 14- on which the bolster is slidable, the bolster having laterally spaced guide ribs 19-19 and 19-19 at opposite sides of each end thereof embracing said guide portions 18-18.
My improved friction shock absorbing mechanism, as shown in the drawings, comprises broadly a pair of friction, shoes A-A at each end of the truck bolster mounted at opposite sides thereof, a wedge member B within the bolster at each end thereof engaging the shoes A-Aand bearing on the upper ends of the inner coil springs 15-15 of the spring units at opposite sides of the corresponding spring cluster, and swivelled friction blocks C-C mounted on the guide portions 18-18 of each side frame.
In carrying out my invention, I provide each side frame 10 of the truck with pockets 20-20 at the bolster guide portions 18-18, each pocket opening inwardly towardthe bolster and having a substantially vertically extending concave back wall 21, which presents a spherical bearing surface 22 for the friction block C.
The friction blocks C-C of each side frame 10 are seated in the pockets 20-20 and have ball or spherically shaped bearing faces 23-23 on their rear sides engaging the spherical surfaces 22-22 of the pockets 20-20. The front sides of the blocks C-C present flat friction surfaces 24-24 which cooperate with the friction Shoes A-A.
The friction shoes A-A and A-A are arranged in pairs at opposite ends of the bolster 14, the shoes of each pair being carried at opposite sides of the bolster. Each shoe A has a flat top end face 124 which slidingly engages a fiat guide surface 25 on the underneath side of the top wall 26 of the bolster 14 at the corresponding side of the latter. Each shoe A project through an opening 27 provided in the corresponding side wall of the bolster and engages the adjacent friction block C. The shoe A is provided with a flat, vertically disposed friction surface 28 on its outer side, which slidingly engages the friction surface 24 of the block C. On the inner side, each shoe A presents a downwardly facing, laterally inwardly extending, inclined wedge face 29, which is engaged by the wedge member B.
The wedge member B is in the form of a rectangular plate, which is cut out or slotted at the top at opposite sides thereof, as indicated at 30-30, to accommodate the wedge portions of the shoes A-A. The inner wall member of each of these cut out or slotted portions is inclined, as shown, and provides a wedge face 131 which cooperates with the wedge face 29 of the corresponding shoe A. The member B spans the distance between and overhangs the springs 15-15 and 15-15 at opposite sides of the central spring unit of the cluster and has depending bosses or lugs 31-31 and 31-31 at opposite end portions thereof, which are aligned with and engage the upper ends of the inner coil springs 15-15 and 15-15 of the spring units at opposite sides of the central unit of the five unit spring cluster, the bottom wall of the bolster 14, which wall is indicated by 32, and the usual top spring follower plate of the spring cluster, which plate is indicated by 33, being provided with aligned openings 34 and 35 through which these lugs 31 extend.
As will be evident, as the bolster moves downwardly to compress the spring cluster, the springs 15-15-15- 15, which bear on the wedge member B, are also compressed and force the wedge member against the shoes with progressively increasing force to press the shoes against the friction surfaces of the friction blocks C-C, thereby providing high frictional resistance to snub the action of the truck springs.
I claim:
1. In a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically movable between said guides; of springs supporting said bolster on said truck side frame; friction shoes carried by said bolster; a wedge member within said bolster in wedging engagement with said shoes; a plurality of depending lugs on said wedge member, and a spring for each of said lugs extending therefrom to said truck side frame to urge the wedge member against said shoes, each of said latter springs being disposed concentrically within one of said bolster supporting springs.
2. In a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically niov-- able between said guides; of a cluster of springs supporting said bolster on said side frame, said cluster including a central spring unit, and additional spring units arranged at opposite sides of said central unit, each of said spring units including an inner coil spring and an outer coil spring; friction shoes carried by said bolster; and a wedge member in wedging engagement with said shoes, and lugs depending from said wedge member into engagement with said inner coil springs of all of said additional spring units to support the wedge member.
3. In a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically movable between said guides; of a cluster of springs supporting said bolster on said side frame, said cluster including a central spring unit, and additional spring units arranged at opposite sides of said central unit, each of said spring units including an inner coil spring and an outer coil spring; friction shoes carried by said bolster; and a wedge member in wedging engagement with said shoes, and lugs depending from said wedge member into engagement with said inner coil springs of all of said additional spring units to support the wedge member, and the bolster being supported on said central spring unit and the outer coil springs of said additional units.
4. In a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically movable between said guides; of a cluster of springs supporting said bolster on said side frame, including a central spring unit, and additional spring units arranged at opposite sides of said central unit, each of said spring units including an inner coil spring and an outer coil spring; friction shoes carried by said bolster and slidably engaging said friction surfaces of said guides; and a wedge member in wedging engagement with said shoes, said wedge member having depending lugs thereon said lugs extending into engagement with the inner coil springs only of all of the additional spring units to support the wedge member.
5. In a railway car truck including a truck side frame having vertical bolster guides presenting friction surfaces thereon, the combination with a bolster vertically movable between said guides; of a cluster of springs supporting said bolster on said side frame including a central spring unit, and additional spring units arranged at opposite sides of said central unit, each of said spring units including an inner coil spring and an outer coil spring; a pair of friction shoes mounted at opposite sides of said bolster, said shoes being laterally movable on said bolster and having sliding engagement with the friction surfaces of said side frame; and a wedge member in wedging engagement with said shoes to spread the same apart, and lugs depending from said wedge member into engagement with said inner coil springs of all of said additional spring units to support the wedge member.
6. In a railway car truck, including a truck side frame having a bolster receiving opening which is provided with vertically extending interior friction surfaces at opposite sides thereof, the combination with a truck bolster within said opening, said bolster having vertically spaced, top and bottom walls; of a cluster of spring units supported on said side frame beneath said bolster, said cluster including a central unit and an additional pair of units at opposite sides of said central unit, each unit including outer and inner coil springs, said bottom wall of the bolster having a plurality of openings extending therethrough, said openings registering with the inner coils of said pairs of spring units which are at opposite sides of the mechanism; a pair of friction shoes at opposite sides of said bolster having sliding engagement with the friction surfaces of said side frame, said shoes having wedge faces in the inner sides; a wedge plate having wedge faces at opposite sides thereof engaged with the wedge faces of said shoes; pairs of depending bosses on said wedge plate at opposite sides of the center of said plates, said bosses being aligned with and engaging said inner coil springs of said pairs of springs, said bosses extending into the openings of said bottom wall of the bolster and resting upon the upper ends of said inner coil springs only of said pairs of spring units.
References Cited in the file of this patent UNITED STATES PATENTS 2,365,199 Light Dec. 19, 1944 2,550,910 Chistenson May 1, 1951 2,548,223 Lehrnian Apr. 10, 1951 2,570,159 Schlegel, Jr. Oct. 2, 1951 2,574,348 Orr et al. Nov. 6, 1951 2,583,144 Hamilton Jan. 22, 1952 2,675,765 Hamilton Apr. 20, 1954 FOREIGN PATENTS 473,848 Canada May 22, 1951
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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2365199A (en) * 1941-10-11 1944-12-19 American Steel Foundries Truck
US2548223A (en) * 1945-09-04 1951-04-10 American Steel Foundries Snubbed bolster truck
US2550910A (en) * 1945-04-28 1951-05-01 Gust J Christenson Snubbed bolster truck
CA473848A (en) * 1951-05-22 P. Leese Charles Stabilized lateral motion trucks for railway cars
US2570159A (en) * 1945-08-17 1951-10-02 American Steel Foundries Snubbed bolster truck
US2574348A (en) * 1945-04-30 1951-11-06 Buckeye Steel Castings Co Damping means for railway trucks
US2583144A (en) * 1944-12-26 1952-01-22 Karl M Hamilton Railroad car truck
US2675765A (en) * 1954-04-20 Railroad gar truck bolster

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA473848A (en) * 1951-05-22 P. Leese Charles Stabilized lateral motion trucks for railway cars
US2675765A (en) * 1954-04-20 Railroad gar truck bolster
US2365199A (en) * 1941-10-11 1944-12-19 American Steel Foundries Truck
US2583144A (en) * 1944-12-26 1952-01-22 Karl M Hamilton Railroad car truck
US2550910A (en) * 1945-04-28 1951-05-01 Gust J Christenson Snubbed bolster truck
US2574348A (en) * 1945-04-30 1951-11-06 Buckeye Steel Castings Co Damping means for railway trucks
US2570159A (en) * 1945-08-17 1951-10-02 American Steel Foundries Snubbed bolster truck
US2548223A (en) * 1945-09-04 1951-04-10 American Steel Foundries Snubbed bolster truck

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