US2366180A

US2366180A - Car truck

Info

Publication number: US2366180A
Application number: US418006A
Authority: US
Inventors: Robert B Cottrell
Original assignee: American Steel Foundries
Current assignee: American Steel Foundries
Priority date: 1941-11-06
Filing date: 1941-11-06
Publication date: 1945-01-02
Anticipated expiration: 1962-01-02

Description

Jam 2a 1945- R. B. COTTRELL 2,366,150

CAR TRUCK Filed Nov. 6, 1941 5 Sheets-Sheet l y Jan. v2,l 1945.

R. B. CQTTRELL CAR TRUCK Filed NOV. 6, 1941 3 Sheets-Sheet 5 Wisel'engagessaid columns. t y l My invention `alsofcomprehends smlchanzir` rangement1 as that just described whereinthel s `20` t Inemloerand of the bolster-ends are similarwso t Patented fJan. 2, y

"assenso `Rfobert i AmericanSteel Foundries, Chicago, Ill., a cor- `porationoli-Newiiersey My invention relates to a railway cartruck and especially to` a type "of ltruck commonly used sin freight carsl with `spaced truss typeuside. frames and a6 connecting bolster or, load carrying Tmember.

t `A Ageneral objectief mylin'ventionis to devisegan wheel change truck;l especially` adapted for use in high speed service. t t t o ,A specificl object of t my :inventionx is `to `devise a practical form oflhighvspeedtruok of1quicktwheel change type Whereineacliside framegis afforded bolster guide meanswcentrally "of, `the columns,

and .the ends of `the bolster are formed Wthi shelf` portions which may engage lwiththe .columns-asf Well l as" with an interlocking-` ymember, which likecolumn engaging surfacesQof `the interlocking surfaces on the guide. Columna` l i y ;A diiferentobject of my invention istomdeyise a freight ,carltruck of the abovegeneraigtype thateach may `engage lthe sar-ne` ;fcor`npleme ntary improved form of a `Well-known `type o fnoquick thel-Sdeiframettaken substantially inth'e plane y indicatedbyjthetlie 5%5 of Figure A1. l t

y Figures "6 an'd ,'Zyshow .thejdetail of my-"novel y i frmfof interlocking member; .gulef being a half@top lraan,I andjRigure 7 ahalf iside :elevation my 4novel truck arrangement." Figure L8 .being` a I intermediate.

iragrilelita-'Cy` longitudinaluertdal sectional `View in l a fplanelfljust)outboard1thelirictionshoe carrier, `Figure 9, y 1a' fragmentary, 1 Vertical sectional Figuren 8f, Aanld' Figurel .'10 affurthenfragmentary sectional View ,takenlin the" horizontal transverse pianeindicatenlybyrhenne,wenn of Figure s; y l shows aiurther In diiication of `the y uni-ing the montani@ supporta i `My novel `truck arrangement comprises a cornpressionmember atensionmeinber 4,`merging attheir 1.ends",asatifiifol:connection Lto Wheel COnriecting/trrieans ,met shown) and i-QDIIiected 25 whereini the `.interlocking `member. may have integrally` formed therewitha housing Withspaced friction .Walls into engagement Withtv Whichmay t be resiliently 'urged friction shoes. for `slidablercooperationtherewitm t t l l i ,My novel ,arrangementlmay lfurther icompreelevation fof Eigllrel; "The tensionmand compreslsonfmembersland ,spaced columns t "delne `the y usual t central-.bolster Iorienin'gll 0 and over `said bolster opening 4`time ..Qomnression member may haw/eine tn0X-,sea-ion:indicated at l2 ninguna 3,

While 1` beneath jsaidfbolsteryopening .the ,tension y member .may likewise harefarboX-fsection `With .a

hend. such; a structure as `thatabove iset forth wherein the friction ,shoes for @cooperation with the friction ,surfaces on the interlocking` member may b e l conveniently fand removably supported from the `tension` member offthe side `frame.

)In thewdrawings, Figure 1` isW a fragmentary side elevation fof` aurailway car trucka embodying myfinvention, onlyoneendportion of the side frame `being illustrated inasmuch as the structure is similar, at oppositeends. l V i r Figure 2 is= a fragmentary `top planvew of the truckstiucturefshown in Figure Land Figure"3` is-` a fragmentary sectionalA view thereof,"the"sec7 tionbeing taken inJ the `Vertical plane "bisecting l central',` l member-maybe widened?underlsad'blster Openbottom chord I4, a topchord `Hi,A nboai'd andl outboardsde Wallsl i and 26 reinforced by i triangular 4ribs"11'42"3122., y.said tnsion i member section y being. further nforced bythe` longitudinal 16.1241 "The top iWeb I 6, "of dsaid. .tension ing` to define the spring seat 2 5, and forme d with v upstandingginboartdand outboard flanges `26 seatedpnthe Ls `the truck transversely and as indcatedllby iheI imately :through taken inthe vertical plane indicated bythe linel 4-"4 oflFgure 1, lsadsection being,takenfapprcix-` the `'middle yor one infine "niotion devices; y

be alignedlalong, thel inboar'd t andoutboardl ,edges of.saidlspringtseatlas best seen in' .the top `plan tion devicetherebetween tofbelmore particularly describedhereafter.l "3 t y I y y y j @Extendii nintothe.daolsteit.opening,Iii maybe the end ofsthebolster ."gelgierally, designated 40, l Seid bolster @was widened top prtivn i .with acshelfelileastrueturel Maaatgeach t-nsicleu1 thereof,

heir ends `by snacedlcolumns 8, 8, l

the

respective side walls

82, 82.

said'shelf-like structure having a depth A (Figure 1) less than the clearance B above the centrally disposed bolster guide ilange 44 on the adjacent column so that said bolster may be pro` of the adjacent column is convex and complementary to the side Wall ofthe bolster as may be noted at 50. l

The end of the bolster 40 is of general boxsection with a top wall 52, abottom wall 54 with downwardly projecting spring positioning lugs 55,

55, a side wall 56, and a central, vertical longi-j tudinal flange 58., AThe bottom wall 54 is aiiorded a shallow transverse recess extending thereacross for reception of the base wall 60 of the' interlocking'c'asting generally designated 62, said interlocking casting having at each end thereof a Vertical portion 64 with a side wall contour similar to that of the bolster and complementary to the guide surface on the adjacent column asmay be noted at 66 in the top plan yview of Figure 6. Each end portion 64 is formed with a flat inner face 68 which may abut as at 10 (Figure 1) the adjacent side Wall 56 of the bolster, and said vertical portion 64 may be interlocked with said casting 62 is a friction housing 80 extending for substantially the length of said casting and depending from the base `wall 60 thereof, said housing 80 comprising

parallel side walls

82, 82,an

intermediate wall 86, andeend

wallsV

88, 88 reinforced by the triangular ribs 90,l 90 in line with r1l`he intermediate wall 86 may be cored away at its bottom end as best seen at` 94 in the sectional view of Figure 3 and core openings may also be formed in the upper corners thereof as at 96, 96 for c onvenient foundry practice.

The friction housing 80 is openat its lower en d, and said housing projects downwardly from'the bottom of the interlocking casting 62 for cooperation with friction means supported from the tension member of the side frame. Said friction means comprises similar arrangements at respective ends of the housing 80, only one of which may be described. Each friction means 'comprises a plurality of friction shoe supports 98,

98 having bases |00, |00 recessed as at. |02 in the top web of the tension member, each of said shoe supports having a vertical leg |04 projecting upwardly through an associated slot |06 in the retaining plate |08, also recessed inthe top web of the tension member, and seated as at ||0, ||0

-(Figures 3 and 4) on the shouldered edge of the recess at |02. The plate |08`has a top surface coplanar with the top surface of the web `I6 of the tension member, said plate thus forming a portion of the area on which may be superposed the

coil springs

38, 38 so that said coil springs serve to maintain said plate and said friction shoe supports in normal operating position. Chatter may be avoided by utilizing a rubber pad 2 under the bases of the shoe support if desired, as illustrated in the sectional views of Figures 3 and 4. At th upper end of each friction shoe support |04 may be carried a friction shoe ||4 having frictional engagement as at 6 with the adja- I

cent side walls

82, 82 of the housing 80, and un' der-compression between the opposed friction shoes ||4,v ||4 may be the rubber pad ||8 positioned with respect to said shoes as at |20, |20.

`In this arrangement, each friction shoe I4 is relatively large and has Aone entire face in flat frictional engagement with the adjacent wall of the friction housing and, inasmuch as four of such shoes are afforded, it will readily be seen, i that a large amount of friction can be developed if desired without undue wear. At the same time, the degree of friction developed may be controlled within reasonable limits by the character of the resilient member I8 compressed between opposed shoes.

In the modification illustrated in Figures 8, 9, and 10, the side frame structure may be generally similar to that of the previous modification and include the tension member 202 and the integral column 204 with the-bolster guide lug 206 formed on the upper portion thereof, saidtension mem-l ber beneath the bolster opening 208 having a boxsection with a bottom web 2|0, inboard and outboard walls 2|2 and 2|4, the intermediate longitudihal rib 2|6, and the top chord 2|8 reinforced by the upstanding inboard and

outboard flanges

220 and 222, thus defining the spring seat 224 on which may be positioned a plurality of coil springs diagrammatically indicated at 226, 226 l(Figure 10). Upstanding

lugs

228, 228 may serve to position the respective coil springs, and

additional positioning lugs

230, 230 may be formed'on said yspring seat, intermediate adjacent coils, as best seen in the View of Figure 10.

l As in the previous modification the top chord 2|8 of the'tension member defining the `spring seat may be recessed as at 232 for reception of the friction shoe retainer plate generally designated 234, said plate having a rectangular'base, the top face of which may be flush with the spring Vseat 224 in order that the respective coils seat thereon as best illustrated in Figure l0. At each end of the retainer plate 234 and centrallypositioned thereon may be the upstanding T-section lug 236 at opposite sides of which may be carried friction'

shoes

238, 238, each of said shoes being slotted at its lower vend as at 240 for mounting-on said lug `238. Each friction` shoe may have secured there- In this modification the integrally 'formed interlocking member and friction housing generally designated 250 is similar in `form and func-I tion to thatof the previous modification and Ycomprises the base wall 252 and the

upstanding end portions

254, 254 for interlocking engagementwith the

guide lugs

206, 206 on'the respective columns of the side frame, said interlockingA member 250 also comprising the upstanding cen'-l ascenso trai-'111g zj5s-whie1frmay be interloekerwitii they bolster as *described forthe vprevious f modifica- `tion` as well as the itransverser-rib"258 at jeach end thereof reinforcing the adjacentjendportion 254 and-also yrecessed inthe lateral wall of the bolster also Ain previous modification.

manner describedfor the t The dependingfrictionlhousing formedas an integral part of the member 250 -may `havethe `lateral walls thereof `reinforcedbyjspaced depending -ribs 260, 260and at the juncture of` eachrib with the base plate 252 `maybe formed spring positioningvmeansfZGZ,1262. `Each end wall`1264 of the friction housing `maybe cored away as at 266, 266 Figure `8) to reduce `the weight therfeofwSimilarly the baseplate`252 maybe cored away as at 268;` i

'Figure 1i r have iuustrated `afurtner `slight member 302`has a top chord 304 defining `the spring seat 306 on which may be positioned resilient-,meansas described for the previous modications. shown in Figure 11, the `spring seat 306 mayhave integrally formedupstanding T-section lugs 308 at each-side thereof on which may be positionedjfrictionshoes jfragmentarily indicated at 3I0, 310' in mannersubstantially identical to the showing of Figure 9 except that the 11p-standing lug in `the modification in Figspaced columns deninga `central bolster opening, `a `spring group' on 4said `tension member in saidopening, a bolster `extending into said opening in `guiding engagement `with said columns, an interlocking `member associated with said bolster and in guiding engagement )with said columns,

said bolster and interlocking member` being seated on said spring group; saidfinterlocking member having *integrally formed"therewith` depending walls with opposed friction surfaces, friction "shoe supports having bases recessed in the top chord of said tensionimernber, retainingmeans Ithere-v for, each `of said supports having a vertical leg extendingV through said retainingmeans, friction shoes supported on said vertical legs in engagementiwith said opposed friction surfaces, and resilient means under compression between s-aid friction shoes. m

2. In a railway car truck, `a `truss side frame having tensionand compression `members and spaced columns dening a bolster opening,bolster guide jmeans on, each of said Icolumns Acentrally thereof, a'bolster extendingdnto said` openingl with a widened shelf-like topportion in `guiding engagement with said columns, and an interlockingmember recessed in the bottomwallof said bolster and having. upstanding ends cooperating `with said lshelf portionf'and also inguidingrengagement with `said columns, nsaid 'interlocking member f having .integrally formed Atherewith spaced friction surfaces, means on 'said tension memberfsupporting frictionshoes nfor engagement W'lth. said surfaces respectively; vandfnesilient 4 modification `wherein the 'box-section Atension l surfaces. t l im i i f 3. `In a `railway -car truck, a;l sideframe` having i s-hoes in engagementfwithjrespective friction atension `member and spaced columns `defining in `part a bolster openingaspring group on said` tension member, a bolsterjjextending1into"said` openingwith af-topshelf portion of restricted depth in guiding engagement-with=said columns,

an interlocking member 'fixed tol saidA bolster"in` i cooperative engagementwith said columnsysaid interlocking member having walls with opposed friction surfaces,` means on said tension member supporting friction shoes `in engagement with `said surfaces,`and aresilient pad under compression between said-friction shoes, said topfshelf portio'nlhaving` Ia depthv less than the clearance between thebolster` guide 'surfaces on saidcolumns and the top of said bolster` opening. i

4.* In a railway 'car truck, a side frame having tension and compression `members `and spaced columns defining a bolsteropeninga springseat on saidtension memberin` said opening, 'a springgroup thereon, Aa hbolster `extending into said .opening in guiding `engagement with saidfcolumns, an interlocking member cooperating with said "bolsterand said columns, said interlocking member` and bolster being :seated `on said spring- `group, said spring group' `comprising `springs aligned along'the inboardand outboard edges of said seat, saidlinterlocking 'member having -fric`` n pression between said friction shoes.

5; Ina railway `oar truck, a side framehaving tension and compression members and* `spaced columns defining a "bolster `opening, `a spring group onlsaid tension member in `said opening, a

bolsterextending intosaid opening in `guiding engagement with `said columns, an interlocking member `associated withsaid bolster and in guiding engagement with said columnsysaid bolster and interlocking `memberbeing `seated on `said fspring group, saidinterlocking member having `a housing with opposed -friction surfaces, means mounted on said tension member `supporting friction shoes in engagement'with therespe`c-` tive friction surfaces, and` resilient `means -`under compression between said shoes.` i `6. Ina railway car truck, `a truss side-frame havingftension and` compression membersrand spaced columns dening a central bolster `open` ing, a yspringgroupon said tension member in said cpeninga bolsterextendinginto said -opening in guiding `engagement "withysaid columns,"

an interlocking memberlassociated with said bol# ster and in guiding engagement with Vsaid 3co1 umns, said bolster 'andinterlocking memberjbeing seated on Wsaid spring group, said interlocking member having integrally formed therewith "de-` pending 'walls Withopposed friction surfaces,

friction` shoe "supportsl carried on saidv tension member, friction shoes mounted on said supports in `engagement with said friction surfaces,` and resilient lmeans under compression between said l shoes.

, 7. In a railway `car truck, a side frame having `a tension member and spaced columnsdening inA part a bolster opening,a spring group on Said tensionmember, a bolster extending into said opening withfr'a top `shelf .ortion ,of restricted means underwcompression "between fthe ifrictionrl an interlocking member fixed to said bolster incooperative engagement with said columns, said interlocking member' having means with opposed friction surfaces, and means on said tension member supporting friction shoes in engagement with said surfaces, said top shelf portion having a depth less than the 'clearance between the bolster guide surfaces on said columns and the top of said bolsterv opening.

`8. In a railway car truck, a 4side frame having tension and compression members and spaced columns defining a bolster opening, a spring seat on said tension member in said opening, a spring group thereon, a bolster extending into said opening in guiding engagement with said columns, an interlocking member cooperating with said bolster and said columns, said interlocking member and bolster being vseated on said spring group, said spring group comprising springs aligned along the inboard and outboard edges of said seat, said interlocking member having friction Walls depending between said inboai'd and outboard springs, friction shoe supports carried on said tension member, and friction shoes supported therefrom in engagement with said friction surfaces.

9. In a railway car truck, a truss side frame having tension and compression members and spaced columns defining a bolster opening, bolster guide means on each of said-columns centrally thereof, a bolster extending into said opening with a widened shelf-like top portion in guiding engagement with said columns, and an interlocking member recessed in the bottom wall of said bolster and having upstanding ends cooperating with said shelf portion and also in guiding engagement with said columns, said in-` terlocking member having depending spaced friction surfaces, and means on said tension member supporting friction shoes for engagement with said surfaces respectively.

10. In a railway car truck, a side frame `having tension and compression members and spaced columns defining a bolster opening, a spring group on said tension member in said opening, a bolster extending into saidl opening 'in guiding engagement with said columns, an interlocking member associated With said bolster and vin guiding engagement with said columns, said bolster and interlocking member being seated on said spring group, said interlocking member having depending means with opposed friction surfaces, and means mounted on said tension member supporting friction shoes in engagement with the respective friction surfaces.

` 11. In a railway car truck, a truss side frame having tension and compression `members and spaced columns defining a central bolster opening, a spring group on said tension member in said opening, a bolster extending into said opening in guiding engagement with said columns, an interlocking member associated with said bolster and in guiding engagement with said columns, said bolster and interlocking member being seated on said spring group, said interlocking member having walls with opposed .friction surfaces, friction shoe supports carried on said tension member, and friction shoes mounted on said supports in engagement with said friction surfaces.

12. In a car truck, a truss side frame having a central bolster opening, a spring group on said side frame, a bolster seated on said spring group in said opening in cooperative engagement with said frame, and a member fixed to said bolster for interlocking said side frame and bolster, said interlocking member having spaced depending Walls, friction surfaces on each of said Walls, friction shoe support means carried on said frame,l friction shoes mounted on said support means in engagement with said friction surfaces, said `friction shoes being mounted in pairs with the respective shoes of each 'pair in opposed `relationship to each other, and resilient means under compression between the shoes of each pair.

13, In a railway car truck, a side frame having tension and compression members and spaced columns defining a bolster opening, bolster guide means centrally positioned` on said columns, a spring seat on said tension member in said opening, a spring group thereon, said spring group comprising springs aligned along the inboard and outboard edges of said seat, a bolster extending into said opening in guiding engagement with said columns, an interlocking member securedto said bolsterin cooperative engagement with said columns, said interlocking member having integrally formed spaced friction surfaces, means on said tension member supporting friction shoes in. engagement with said surfaces, and a resilient member under compression between said shoes.

14.v In a railway car truck, a side frame having a tension member and spaced columns defining in `part a bolsterl opening, a spring group on said tension member, a bolster extending into said opening with a top shelf portion of restricted depth in guiding engagement with said columns, an Yinterlocking member secured to the bolster in cooperative engagement with said columns, ysaid interlocking member having walls with opposed friction surfaces, means on said tension member supporting friction shoes in engagementV with said surfaces, and resilient means under compression betweensaid friction shoes.

15. In a railway car truck, a side frame having tension and compression members and spaced columns dening a bolster opening, bolster guide means centrally positioned on said columns, a spring seat on said tension member in said opening, a spring group thereon, said spring group comprising springs aligned along the inboard and outboard edges of said seat, a bolster extending into said opening in guiding engagement with said columns, an interlocking member xed to said bolster in cooperative engagement with said columns, said interlocking member having integrally formed spaced friction surfaces, and means on said tension memberV supporting frictionshoes in engagement with said surfaces.

16. In a railway Qar truck, a side frame having a tension member and spaced columns defining in part a bolster opening, a spring group on said tension member, a bolster extending into said opening with a top shelf portion of restricted depth in guiding engagement with said'columns, an interlocking member secured to said bolster in cooperative engagement with said columns, said interlocking member having depending Walls with opposed friction surfaces, and means on said tension member supporting friction shoes in engagement with said surfaces.

17. In a car truck, a truss side frame having a central bolster opening, a spring group on said side frame, a bolster seated on said spring group in said opening in cooperative engagement with said frame, a member secured to said bolster for interlocking said side frame andl bolster, said interlocking member having depending walls with opposed friction surfaces, means mounted on said side frame supporting friction shoes in engagei i i 2,366,180`

ment with said surfaces, and a resilient pad under compression between said shoes.

18. In a railway car truck,- :a side frame comprising a bolster opening, a spring group on said frame in said opening, a bolster supported on said spring group, anda friction absorbing device beneath said bolster and comprising followers supported fromsaid frame and said bolster respectively, and friction shoes supportedby one of said followers and resiliently urged into engagement withthe other, one of said followers having a wall recessed in said bolster and afford-` ing a seat coplanar with the bottom wall thereof for abutment `of saidspring group, said spring` group affording the sole means of retaining said last-mentioned follower in normal relationship with said bolster.

19. In a railway car truck, a side frame comprising a bolster opening, a spring group on said frame in said opening, a bolster supported on'said spring group, and a friction absorbing device comprising followers supported from said frame and said bolster respectively, and friction shoes supported by one of said followers in engagement with the other, at least one of said followers being partially recessed in its supporting member and withsaid member affording a, coplanar seat for one end of said spring group, said spring group acting to retain said last-mentioned follower and its supporting member in normal relationship.

20. In a railway car truck, a side frame member comprising a bolster opening, resilient means on said member in said opening, a bolster mem-` ber supported on said means, a follower compris'- ingwspaced friction walls supported beneath said" bolster member from one of said members, fol` lower stems each comprising a base recessed in` the other membena retaining plateirecessed in the last mentioned member and comprising slots therethrough, said follower stems projecting.A

through said slots, friction means on said stems in engagement with respective walls, and resilient means urging said friction means into said engagement.

21. Ina railway car truck, aside frame member comprising a bolster opening, resilient means on said member in said opening, a bolster member supported on said means, a"'follower comprising spaced friction walls supported beneath said bolster member from one of said members, follower stems each comprising a base recessed inthe other member, a retaining plate recessed in the last mentioned member and comprising slots therethrough, said follower stems` projecting through said slots, frictionmeans on said stems in engagei `ment with respective walls, a resilient pad ,com-` pressed between said` bases and the associated member, and resilient means urging said friction means into said engagement.

22. In a railway car truck, a frame member comprising a bolster opening, resilient means on` said frame member in said opening, `a bolster` member supported on said means, alfollower comprising spaced friction walls supported beneath said bolster member from one 0f said members.. `follower stemseach comprising a base recessed in the other member, means retaining said bases in assembly and permitting restricted movement thereof with respect to the associated member, friction means on said stems in engagement with respective walls, and resilient means urging said friction' means into said engagement.

23. In a railway car truck, a frame member comprising a bolster opening, resilient means on` l said frame member in said opening, a bolster member supported on said means,` a follower associated with one of said members and comprising spaced friction walls beneath the bolster member, a T-shaped follower associated with the other of said members, friction shoes comprising openings slidably receiving the respective horizontal flanges of said T-shaped follower, and resilient means under compression between said shoes for urging theminto engagement with resp'ective walls.

24. In a railway car truck, a side frame comprising a bolster opening, a group of springs on said frame in said opening, a bolster supported .on said group, and a friction absorbing device comprising a follower having a web recessed in the bottom wall of saidbolster and affording a surface coplanar with the bottom of said wall for abutment of said group, said springs being seated partially against said vsurface and partially against said wall, and friction means supported from said frame in frictional engagement with said follower. i

25. In a railway car truck, a side frame having spaced columns at opposite sides of a bolster opening, a group of springs on said frame in said opening, a bolstersupporte'd on said group, a-r'id a friction absorbing device `comprising a follower having a web recessed in the bottom wall of `said bolster and affording a surface coplanar with the bottom of said wall for, abutment of said group, "said springs being seated partially against said surface and partially against saidwall, and friction means supported from said frame in engage `ment with said follower, portions of said followery i being interlocked with said columns.

26. In a railway car truck, a side frame having spaced columns at opposite sides of a bolster opening, a spring group on said frame in said opening, a bolster supportedfon said group, and 'a friction absorbing device beneath said bolster and comprising followers supported respectively from said frame and said bolster, and friction shoes supported by one of said followers and resiliently urgedl into engagement with the other,

one of said followers having a wall recessed in said bolster affording a seat coplanar with the` bottom wall thereof for abutment of said group,

said spring group affording the' sole means of rejtaining said last-mentioned follower in normal relationship with said bolster, at least one of said followers having interlocking engagement `with supportedrespectively from said frame and said bolster, and friction shoes supported by one of` said columns.

27g In a railway car truck, a side frame comprising spaced columns defining in part a bolster l opening, a spring group on said frame in said opening,` a bolster supported on said group, and a friction absorbing device comprising followers said followers in engagement with the other, at least one of said followers being partially recessed in its supporting` member and with said member affording a coplanar seat for one end of said group, said spring group acting to retain said last-mentioned follower` and its supporting member in normal relationship, and at least one of said followers having an interlockwith said columns.

`ROBERT B. COTTRELL.