US2657041A

US2657041A - Snubbed spring group

Info

Publication number: US2657041A
Application number: US199601A
Authority: US
Inventors: Robert B Cottrell
Original assignee: American Steel Foundries
Current assignee: American Steel Foundries
Priority date: 1950-12-07
Filing date: 1950-12-07
Publication date: 1953-10-27
Anticipated expiration: 1970-10-27

Description

Oct. 27, 1953 R. B. coTTRELL 2,657,041

SNUBBED SPRING GROUP Filed Dec. 7L 1950 INVENTOR.

Patented Oct. 27, 1953 vii-Nieren -s*11Aras iPArELNi :carica SNUBBED` SPRING GRoUP Robert "B. Cottrell, Chicago, "111., .assigner to American Steel"Foundries, Chicago, Ill.,:.a .corporation of New Jersey :Application December 7, 1850,-5SerialNo.199;601

Aand ybottomplates .and .snubbing .synchronous os .cillationsof thespringgroup.

.A more specific object oftheinvention .is .to .providea ,floating .friction .assembly which will ,yieldinglv resist .sidewise .movements between the ...top .and .bottomportions `of the .spring group without.imposingexcessive .stresses ,on the parts .of thesnubbing or .frictiondevceand its .con- .nections with the A.topand [bottom plates.

.Anotherobiect .of the invention .is to provide `a novel .spring group wherein.gthespartsotthe friction device are arranged 4to obtainmaximum .spring rcapacityior actuating. the: devicewithout ..encroaching .on the spaceifor thejload coils or reducingthe strength .of thepackage.

.These and other objectsof `the, invention will become ,more apparent .from .the speciiication andthe drawings,- wherein.:

.Figure .1 yisa rtopplan .view .of .the novel spring Hpackage, onehalf ,of the. top portion of. the .packagelbeing removed .to more..clearly.illustratethe d constructionof.thelbottom. portion.

..`Fig.ure 2 `isanend view, partly .in .section online linel-QZ oflEigure, 1 and AFigure '3 .is a sideelevational `View. .of 'thepackage.

.Describing the invention .in detail, the spring `package. comprises .spaced top.. and. ,.bottorn; plates .2 .and of .scalloplike ,form .a`t..their` ends lto 1.con- .iorm tothe. contour .of the springs .8, 6: .confined therebetweenadjacent opposite-.ends thereof. -.It A.will be seen.that each .set `of :springsmcomprises inner and outer. coils and that fcursets of springs are .employed .and located. Vat .the .four corners. The top .and bottom ,

plateshaveinturnedilanges

8, 8 arranged to conveniently.- contine l Athe.-upper .andlowerends of .the.springs.6, 5.

'AJ friction :device, generally indicated l 0,is lo- `cated centrally .ofthegroup between. the 7springs r6, 6 at opposite .endsof the. group. .The friction A.device .comprises a.friction. casing, -generall-y-:i-n-

dicated `[.2 formed .integral with thetbiottom plate,

,.said. `casing .comprising spacedgenerally parallel .substantially,verticaLside 4wal-ls 1.4,; t4 at .opposite sidesthereof interconnected. ,at .oppositexendsfby .-.spaced .end -wallsill L6. The sidewalls-.endend -`the. top .andfbottom plates.

wallslland lr6 forma substantially rectangular casing. Thelateral edges of the

end Walls

16,16

=at their ,junctures with the side walls .|f4, I4 .mergeintoadjacent portions I8, I8 yof theflange 8 ofthe .bottom plate. The portions` I.8,.l.8.con

verge inwardly on the adjacent side of the `.plate andare Yreinforced .on their external sides by a ...substantially horizontalgusset 2D .wlicnmerges .with fthe .lower edge ofthe .relatedvend Wall 4.6.

The-.bottom plate maybe provided with spaced .depending ,bosses .22.which tare adapted to vitinto `spring Vseat of a side frame or. a-spring plank.

.The friction casing. .or bottom .follower I`IJ. re-

ceives a-stirrup or top follower, ,generallyindi- .cated 24,.ther.ein. The stirrup, top follower yor carrier 124 comprisesspaced substantiallyvertical side Wallsl, 2ty which are disposed. alongside the .walls l |4,.;|-4 of the friction casing and are spaced slightly. inwardly therefrom inorder, tof-accommo- .date horizontal and canting movements between The upper edgesof the .side .wal1s.2.6, 26. merge with .the underside .of

thetopfplatel and ,areconnected at the .upper ends of their external-.sides tohollow` ribbing 2B which depends from the underside of theftop plate and .is designed. to .skirt around and-extend ,between theadliacent sets of springs 6, .E to form positioning means. therefor. ,The ribbing 28, .also

strengthens the topplate. `The lower edges .of

lthe sidewalls

26,26 of the top follower are interconnected by a substantially.horizontalgenerally flat wall. 30 which provides on .its top -sideafriction surface-32 (Figure 2l) on which is `supported -a ,friction assembly `generally designated 34.

.The frictionassembly 34 .is disposed between thesidewalls 26, .26 and comprises at each end .thereof ..-a..substantially triangular .friction shoe `3.6, a troughlike wedge which receives .the lower .ends of an actuating spring 4ttl therein, the ,upper end V`of .the spring seating `as at 42 .against the .undersideofthe top plate`2.

Each shoeV comprises a bottom wall-44 .which .frictionally enga-ges at its bottom side the friction surface32 on the bottom Wall of the stirrup. The

.outer edge of the wall 44 `isconnected to the lower end. of a substantially vertical friction wall 461 .of the shoe, the external side of the wall 46 .havinga friction .surface 4B, which engages ,as at'50..(li!ig ure. 3l a frictionplate 52 mounted `on .theadjacentend wall I6 .of ithefriction `casing in any .convenient manner .preierablvas by `,welding .at

54,.54- .Thefront .wall 46.,.is connectedadjacent ...to its .upperend onitsrear side with the upper end .cfr adiagonal wall. ffthe wallv .55 merging 'at .its lower-sendwith` theyrear .ext1zemity;.rof thetwall acter of the friction assembly.

that by `arranging the wedge member 38 the f= d M. The wall 56 on each shoe presents a wedge surface 58 sloping downwardly inwardly of the stirrup. Each surface 58 engages a surface 60 on the bottom side of a diagonal wall 62 on the adjacent end of the wedge 38. The lower ends o-f the walls 62, E2 of the wedge merge with opposite ends of a substantially horizontal wall 64 at Y the bottom of the wedge 3S, the top side of wall 64 presenting a spring seat as at 65 for the lower end of the compression spring i0 which is compressed between the seat 66 and the top plate 2. The upper ends of the

walls

52, 62 merge with the lower ends of substantially

vertical end walls

68, 68 of the wedge. The wedge 3B is also provided with spaced side walls lli, "Hi, said side walls merging with the lateral edges of the

walls

62, 52, B4 and 68, G8 and forming a pocket 12 therewith receiving the lower portion of the spring 4) therein. Y

In operation, the spring i0 urges the wedge 38 downwardly and the walls 62, EL* thereof 'into engagement along surfaces 66, 5@ with the complementary surfaces 53, 58 on the

diagonal walls

56, 56 of the shoes 36, The shoes are urged downwardly and engage their bottom walls lili with the surface 32. rEhe shoes are wedged apart and caused to engage on the surfaces t8 of the front wall i5 thereof with the

friction plates

52, 52 on the casing as at 50, t. During lateral movement of wedge 33 as shown inFigure 3, the friction assembly 3d is sliolable on the sur:- face 32. Thus it will be seen that excessive stresses are eliminated due to the yielding char- It will be seen form of a trough the pressure imposed against the wedge member is loc-ated at a level which is adjacent to the lower portions of the friction shoes. This feature stabilizes the action of the wedge and also reduces to the minimum bending moments on the spring 4b. In addition, a maximum length of spring is obtained and the leverage onrthe spring due to vertical canting of the wedge is greatly reduced.

Iclaim:

l. In a spring group, spaced top and bottom plates, coilisprings and a friction device confined therebetween, said device comprising a friction casing on one of the plates, a stirrup on the other plate telesccping into the casing and providing a substantially horigontal friction surface at the end thereof remote from and facing sai-:ioL plate, a pair of shoes disposed at opposite s of said stirrup and in frictional engagement with said surface, a wedge member interposed. between said shoes and in wcdging engagement therewith, wedge member being hollow member and presenting a spring seat `.erein disposed substantially closer to said surface than to said other plate, and a single spring extending at one end into said hollow member and seated at one end against said seat and at its other end against the inner side of said other plate and compressed between the same.

2. In a spring group, spaced top and bottom plates, coil springs and a friction device therebetween, said friction device comprising a casing on said bottom plate presenting opposed substantially vertical friction surfaces therein, a stirrup on the top plate extending into Vsaid casing and vhaving a substantially horizontal wall at the bottom end Vthereof presenting a friction face on the top side thereof, a shoe at each side of the stirrup andin frictional engagement on the bottom side thereof with said face and in substanfit) iii)

tially vertical face engagement on its outer side with the adjacent surface, said shoes presenting at their inner sides diagonal wedge surfaces sloping downwardly, a wedge between said shoes having wedging surfaces at opposite ends thereof in wedge engagement with respective wedge surfaces of the shoes, said wedge presenting a spring seat therewithin located adjacent to the bottom extremities of the wedge surfaces thereon and a single vertical coil spring compressed between said seat and the bottom side of said plate, said spring seat being disposed adjacent to the bottom portions of said shoes.

3. In a spring group, spaced top and bottom plates, coil springs and a friction device therebetween, said device comprising a casing on the top side of said bottom plate, said casing presenting internal opposed substantially vertical friction surfaces, a carrier depending from said top plate and telescoping into said casing, said carrier comprising spaced substantially vertical side walls connected at their upper edges tothe bottom side of said top plate, a substantially horizontal friction wall interconnecting the bottom edges of said side walls and presenting a friction face on the top side thereof, a shoe disposed against each surface and in frictional engagement with said face on the forward'and bottom sides thereof respectively, said shoes presenting diagonal wedge surfaces on their internal sides converging downwardly, a. troughlike wedge member interposed between said wedge surfaces and having wedging engagement at opposite ends thereof with said wedge surfaces, said wedge member being Vopen through the top side thereof Vand presenting an internal spring seat on the bottom thereof, said spring seat being disposed at the level of the lower portions of said shoes, and a vertical spring extending into the wedge member and compressed between said seat and the underside. of said top plate.

Li. In a spring group for a railway car truck, spaced top and bottom plates, coil springs and a friction device therebetween, said friction device comprising a friction casing on the internal side of one of said plates, said casing presenting internal substantially vertical friction surfaces at opposite sides, a carrier connected to the other p late'and telescoping into said casing, said carrler comprising a friction face at the end thereof adjacent to said casing and extending tnansversely of the axis of said device, a friction shoe engaging each surface and said face, a wedge member disposed between said shoes and in wedge engagement at opposite ends thereof with the shoes along surfaces converging toward the axis of said' device, side wedge member being hollow and presenting an internal spring seat extending transaxially of the device, and a single coil spring located substantially centrally between said shoes and compressed between said seat and said other plate, saidVv spring seat being located a maximum distance away from said other plate to accommodate a spring of maximum length and to Yeffect a minimum bending moment on said spring.V

5. In a spring group, spaced top and bottom plates, resilient means and a friction device therebetween, said friction device comprising a casing on the top side of the bottom plate with internal opposed friction surfaces, aV carrier depending from the top platev and having a, substantially horizontal Vbottom wall with a friction face on the top side thereof, a pair of shoes disposed one against each surface and having their bottom sides frictionally engaged with said face, said shoes presenting downwardly converging wedge Surfaces on their inner sides, a troughlike wedge member interposed between said shoes, said wedge member having a bottom spring seat wall disposed adjacent to the lower portions of said shoes, diagonal. downwardly converging walls connected at their ylower ends to opposite ends of said bottom seat wall, substantially ver tical end walls at opposite ends of the wedge connected at their bottom ends with the upper ends of the respective diagonal walls, and spaced side walls at opposite sides of the wedge member connected to the lateral edges of said walls of the wedge member and defining a pocket therewith, said diagonal walls having complementary wedging engagement with the wedge surfaces of respective shoes, and a substantially vertical compressed coil spring having its lower portion extending into the wedge member and bearing at its lower end against the top side of said spring seat wall and having upper end seated against the underside of said top plate.

6. In a spring group, spaced top and bottom plates, springs and a friction device therebetween, said device comprising telescoping top and bottom followers connected to respective plates, one of said followers presenting substantially vertical opposed friction surfaces, the other follower presenting a horizontal friction face carrying a pair of shoes in frictional engagement with said sur* faces, a pressure member wedged between said shoes, and spring means compressed between said pressure member and the adjacent plate to clamp the shoes between said pressure member and said face, said pressure member having its pressure receiving areas disposed adjacent to the portions of the shoes closest to said friction face.

7. In a spring group, spaced top and bottoni plates, coil springs and a friction device therebetween, said friction device comprising' telescoping top and bottom followers connected to respective plates, one of said followers presenting opposed friction surfaces, the other follower presenting -a horizontal friction face carrying fric tion shoes in engagement with said friction surfaces, a spring, and a wedge member engaged by said spring and positioned between said shoes urging the same into engagement with said surfaces and said friction face.

8. In a spring group, spaced top and bottom plates, a friction device therebetween, means for urging said plates apart, said friction device comprising telescoping top and bottom followers connected to respective plates, said bottom follower presenting opposed internal friction surfaces, said top follower presenting a substantially horizontal upwardly facing friction face at its lower end, a pair of shoes seated on said .face and disposed one against each surface, a hollow wedge member interposed between the shoes and in wedge engagement therewith, said wedge member presenting diagonal internal surfaces converging towa-rd the bottom of said wedge member and a spring seat between the lower ends of said diagonal surfaces, said diagonal surfaces on the wedge member serving to maintain said spring on the spring seat and preventing the spring from shifting off the seat, whereby the load of the spring is always directed aga-inst the center of the wedge member.

9. In a spring group, spaced top and bottom plates, a coil spring and a friction device theren between, said device comprising top and bottom followers, said bottom follower having spa-ced opposed friction surfaces, said top follower extending between said surfaces and presenting a horizontal upwardly facing friction face at its lower end, friction shoes at opposite sides of said top follower in frictional engagement with adjacent surfaces and said friction face, a wedge interposed between said shoes and in wedge engagement therewith, and a spring compressed between the wedge and said top plate, said wedge engaging said shoes along areas thereof extending from adjacent the top portions of the shoes to adjacent the bottom portions of the shoes, and said spring bearing aga-inst said wedge on an area of the wedge located adjacent to the bottom portions of said shoes.

ROBERT B. COTTRELL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,845,220 Barrows Feb. lf, 1932 2,382,583 Haseltine Aug. 14, 1945 2,390,110 Light Dec. 4, 1945 2,398,750 Light Apr. 16, 1946 2,483,181 Clasen Sept. 27, 1949 2,483,375 Tack Sept. 27, 1949