US1571699A

US1571699A - Friction shock-absorbing mechanism

Info

Publication number: US1571699A
Application number: US608825A
Authority: US
Inventors: Arild M Brenne
Original assignee: W H MINER Inc
Current assignee: W H MINER Inc
Priority date: 1922-12-26
Filing date: 1922-12-26
Publication date: 1926-02-02
Anticipated expiration: 1943-02-02

Description

Feb. 2 1926. 1,571,699

A. M. BRENNE FRICTION SHOCK ABSQRB'ING MECHANISM y Kw4@ A. M. BRENNE FRICTION SHOCK ABSORBING MECHANISM Feb. "2 1926.

2 Sheets-Sheet 2 Filed Dec. 26, A1922 Patented F eb. 2, i925.

UNITED stares ARILD M. BRENNE, OF CHICAGO, LLINGS,

aSSilnl-ltTOiE-b, BY IE'IESNE ASSIGNMENTS, TO

W. H. MINER, l'NC., A CORORATON OF DELAWARE.

FRICTION SHOCK-ABSOIEt-BNG MECHANJSM.

Application filed December To ZZ 'ic/1.0711, it may concer/2..'

Be it known that l', linien lill. BnnNNn, a citizen of the United States, residing at Chicago, in the county of Cook and ,citate of Illinois, have invented a certain new and useful Improvement in Friction Shocl- ,-Xbsorbing lilechanisms, of which the following is a. full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to improvements in friction shock absorbing mechanisms.v

One object of the invention is to provide a friction shock absorbing mechanism especially adapted for railway draft rigging-S, wherein are obtained high capacity and easy release.

Another object of the invention is to provide, in a mechanism of the character indicated, means automatically operable, in compensating' for wear, to gradually increase the effective wedging angle so that loss in capacity otherwise resulting from setting of the springs and loss in initial compression of the springs, is thus offset o1 counterbalanced.

A still further object of the invention is to provide, in a mechanism ofthe character indicated, a wedging system of relatively keen angle character at the initiation of a compression stroke, which wedging system gradually changes, during the progress of the compression stroke, to a wedge system having a blnnter effective wedging angle so that, in obtaining the desired total capacity, a higher initial frictional resistance may be employed in the compression stroke with a resulting lesser ultimate peak load, thereby reducing the ultimate shocks transmitted to the car underframe.

Other objects of the invention will more clearly appear from the description and claims hereinafter following.

[n the drawings forming a part of this specification, Figure l is a horizontal longitudinal sectional view of a portion of a railway draft rigging showing my improvements in connection therewith. Figure 2l is a front end elevational view of the shock absorbing mechanism proper. Figure 3 is a broken vertical longitudinal sectional view corresponding to the section line 3--3 of 26, 1922. Serial No. 608,825.

draw bar is indicated at 13, the same being operatively associated with the shock ahsorbing mechanism proper by a hooded cast yoke 14 within which is disposedthe shock absorbing mechanism proper and a front follower' l5. The yoke and parts therewitht in are supported in operative position by a detachable saddle plate 16.

rlhe improved shock absorbing mechanism proper, as shown, comprises a combined friction shell and spring cage casting A;V

four main spring resistances li-B; a fifth spring resistance C; a. pair of friction shoes D-D; a pair of `wedge elements E-E; a spring cap F; a pair of compensating wedge elements (Si-Gf; and a combined retainer and fulcrum pin l-ll..

The casting A, as shown, is of rectangular cross section having top and bottom walls lil-17, integral rear' vertical wall 18 acting as the rear follower of the mechanism and two side walls 19-19, the latter being made relatively shortso as to leave the major portion of the sides of the casting A open to permit of the insertion and removal of certain of the parts. The inner faces of the side walls 19 are preferably recessed as indicated at 2O to accommodate special wear resisting blocks or liners 21-21, each of the latter being provided on its inner side with a longitudinally extending flat friction surface 522, said surfaces converging inwardly of the shell. y

The two shoes l) are of like construction, each being in the form of ank elongated member having` an outer flat friction surface 23 cooperable with a shell friction surface 2,2. 0n its inner side, each shoe D is provided with a concave bearing surface 24, y

the latter corresponding to the section ofl a cylindrical surface, the center ofwhich isv located in a radius Vperpendicular to the wedge face of one of the wedge elements E hereinafter described. At their inner ends, the shoes l) bear upon a spring follow-er 25, which in turn bears upon the four main lbetween -the two wedge faces 27.

spring resistances B, the latter being'uniformly arranged in the four corners of the spring cage portion of the castingV A.

The two wedge elements E are of like construction, each having a front bearing face y26 engaging the inner side of the front inain E and thus adapting,r the latter to rock orr tilt with respect to each other and with respect to other parts of the mechanism. Stated in another manner, the wedge of the friction unit may be said to consist of two rocker elements having their wedge faces relatively adjustable, for the purposes here- Vinafter described.

Interposed between each wedge element E and the corresponding shoe is one of the elements G, the latter being` segmental in cross section and having' each an outer convex surface 29 cooperating with the corresponding concave surface 24h Cn the side adjacent the axis of the mechanism, each element G- is provided with a flat face 30 cooperable withv the corresponding wedge face 27.

The centrally disposed spring' C is made longer than the other springs B and is ei:- tended through a central aperture 3l in the foll-o-wer 25. To the forward end of the spring C is applied the spring cap F which has a forwardly projecting section 32 of wedge-shape, thus providing two wedge faces The latter cooperate with curved bearing faces 34 so arranged that relative adjustment between the element F and the wedge elements E is permitted.

The operation of the mechanism, assuming a compression stroke in buff, is as follows. As the pressure is applied to the follower 15 and from the latter'transmitted to the wedge elements E, the bearing elements G and shoes D will be forced inwardly of the shell. The initial effective wedging' angle will correspond to the included angle As the elements are forced inwardly of the shell, the shoes D will approach each other laterally, due tothe tapered friction shell surfaces 22, This relative lateral approach of the two shoes D is compensated for by rocking of the two elements E upon the fulcrum pin H in such manner thatthe inner ends of the elements E will laterally approach cach other, thereby squeezing' out the wedge shaped spring cap F. It will be obvious that this action is accommodated by reason of the cooperating concaveand convex bearingl surface-s on the shoes D and bearing members G, respectively. As this action occurs, it is apparent that the included angle between the wedge faces 27 will gradually increase, thus producing a. wedging system of blunter angle effect than was present at the initiation of the compression stroke. iVith this construction, in obtaining' a predetermined total capacity for the mechanism, l am enabled to use a comparatively keen angle to obtain high capacity at the initiation of the stroke with a consequently dccreased nltimate or peak load at the end of the stroke. In carrying` out my invention, the included angle between the faces 33-33 oitl the spring cap will be so chosen that a high lateral pressure will be maintained between the inner ends of the wedge elements E, but yet of sufficient bluntness as to permit the spring'cap being` squeezed out at a predetermined lateral pressure within the Velastic limit of the shell. Stated in another manner, if the included angle between the wedge faces 33 of the spring cap F were made of such acuteness that the cap could not be squeezed out as the compression stroke takes place to permit collapse of the rocker wedge, the shell'mig'ht be expande-d beyond its elastic limit. ln actual practice, the included angle between the wedge faces Btl-3?) will approximate about 'el-00 i Another important feature of the invention resulting' from the construction.shown and described, resides in the following'. As wear occurs on the shell and shoe friction surfaces, the shoes D will separate laterally gradually as the mechanism vremains in service. rlhis allows the inner end of the rocker wedge to expand slightly, the action beine' induced by pressure derived from the spring cap YF. it being understood that the spring C is placed in the gear under initial compression. rthis action on the roclie: wec le'e obviously tends to decrease the ineluded angle between the wedge faces 27--27, thereby increasing the effective wedging action of the wedge systen'i. This has the leffect of compensating for loss in capacitv which might otherwise arise by reason of the springs taking' some set. and also becauseI of the reduced initial capacity in the spring' C as the latter gradually lcngthens, due to the forward movement of the spring cap F in taking up wear.

Dui-ine; the compression stroke, the friction shell will be expanded so that, upon removal of the actuating' force, the energy stored up in the shell will re-act with forces directed inwardly toward the asis of tha: inechanisi'n. These forces will be transmit ted to the wedge El. causing; a sligh further collapse thereof at theinitiation oi the release action, thus increasing the blunt Uri llO

ness of the included angle between the wedge faces 27-27 and facilitating the collapse of the friction unit.

The pin H; in addition to performing its function as a fulcrum for the wedge rocker elements E, also serves to retain the parts in assen'ibled position. By referring to Fig-- ure 3, it will be noted that the pin H has its ends working in `longitudinal recesses 5() provided on the inner side of the top and bottom walls of. the castings A, said pin Ilf being' limited in its forwai'd movement with respect to the casting. Due to the nature of the engagement'between the pin I-I. and the roel-rer elements E; the latter will also be limited in their outward movement with resrect to the casting A, and the same will be true of the remaining movable elements. The pin H may be introduced in ithe casting through a suitable opening 5l in the top wall thereof.

I have herein shown and described what I now consider the preferred mannerof .arrying out my invention, but the same is merely illustrative and I contemplate all changes and modifications that come within the scope of the claims appended hereto.

I cla-im:

l. In a friction shock absorbing mechanism, the combination with a friction shell; of a spring resistance; friction shoes coop erable with said shell; a collapsible pressure transmitting wedge including rocker parts; and angularly adjustable bearing elements between said parts of said wedge and said shoes.

Q. In a fi'iction shock absorbing mechanism. the combination with a. friction shell having intei'ior friction surfaces converged inwardly of the shell; of a spring resistance; friction shoes cooper-able with said shell; a collapsible pressurre-'transmitting wedge ii'icludingi' relatively rocking spreading members; and fulcruin-acting adjustable bearing elements between said rocking meinbers of said wedge and the shoes.

3. In a friction shock absorbing mecha-- nisi'n; the combination with a friction shell; of a spring' resistance; friction shoes cooperable with said shell: a wedge system cooperable witli said shoes. said wedge system havingan original predetermined effective wedgiiigangle; and means interposed between said shoe and wedge system whereby vthe parts of said wedge system are adapted to automatically adjust themselves relatively to each other and relatively to the shoes as wear occurs on the friction surfaces of the shoes and shell, allowing` the shoes to separate laterally, to thereby produce a gradually decreasing edective wedgiiig angle.

4. In a friction shock absorbing mecha.- nism, the con'il'iination with a friction shell having interior friction surfaces converged inwardly of the shell; of a spring resist.- ance; friction shoes cooperable with said shell; a wedging sys-tem cooperable with the slices, said wedge system having an initial predetermined effective wedge angle at the beginning of a compression sti'oke; and adjustable elements coacting with said shoes and wedge system whereby the parts of said wedge system ai'e adapted to automatically adjust themselves relatively to each otherI and relatively to the slices, during` a coinpression stroke, to increase the effective wedging angle.

In a friction shock absorbing mechanisni, the combination with afriction shell having interior friction surfaces converged inwardly of the shell; of a spring resistance; friction shoes coopei'able with` the shell, said shoes having adjustable means thereon presenting wedge faces; and :i wedgiiig system consisting of a plurality of parts cooperable with said shoes; said wedging system having' an original effective predetermined wedging angle automaticallyin creasing by relative movement of the parts of the wedge system as wear occurs on the shell and shoes, the parts of said wedge system also automatically adjusting themselves relatively t-o each other and the shoes during a compression stroke in a manner to increase the wedge angle.

6. In a friction shock absorbing' mechanism7 the combination with a friction shell; of a spring;` resistance; friction shoes coopei'able with said shell; a wedge .system cooperable with said shoes` said wedge system having an original predetermined effective wedging angle; and angularly adjustable means between said wedge system and shoes wherebv the parts ofl said wedge system are adapted to automatically adjust themselves relatively to each other and relatively to the shoes as wear occurs on the friction surfaces of the shoes and shell, allowing the shoes to separate laterally, to thereby produce a gradually. increasing effective wedgiiig angle, said wedge system including two elements pivot-ally mounted with respect to each other.

7. In a friction shock absorbing mechaiiisni, the combination with a friction shell having' interior friction surfaces converged inwardly of the shell; of a spring resistance: frictionshoes cooperable with said shell, said shoes having;` angularly adjustable means thereon; and a wedging system cooperable with angularly adjustable means on the shoes. said wedge system having an initial predetermined effective wedge angle at the beginning of a compression stroke, the parts of said wedge system automatically adjusting themselves relativelv to each other and relatively to the shoes. during a conipression stroke, to increase the effective wedgmg angle, said wedge system including two elements pivotally mountedv with respect fto each other.

8. In a friction shock. absorbing mechanism, the combination with a friction shell having interior friction surfaces converged inwardly of the shell; of a spring resistance; friction shoes cooperable with the shell; a wedging system consisting of a plurality of parts cooperable with said shoes, said wedge system having an original effective predetermined wedging angle; means coacting with said wedge system for automatically decreasing the lwedging angle by relative movementof the parts of the wedge system as wear occurs on the shell and shoes; and angularly adjustable means between said wedge system and shoes whereby the parts of said wedge system also automaticallyV adjust themselves .relatively to each other and the shoes during a compression stroke in a manner to increase the effective wedging angle; said wedge system including two wedgek elements pivotally mounted with respect to each other.

v9. In a friction shoclcabso-rbing mechanism, the combination with a friction shell having interior friction surfaces converged inwardly of theshell; friction shoes cooperable with the shell; a pair of relatively :n

fulcrumed pressure transmitting wedge elements; a follower coacting with said elements; means for yieldingly resisting movement lof said follower and shoes; and bearing elements interposed between said Wedge elements and the shoes, said bearing elements and the shoes having cooperating curved bearing faces and said bearing elements and the wedge elements having flat engaging faces. v

l0. In a friction shock absorbing mechanism, the vcombination witha friction shell having interior friction surfaces converged inwardly of the. shell; of a spring resistance; friction shoes cooperable with the shell; a pair of rocker4 pressure transmitting elements; spreading means lenacting with said elements; an auxiliary spring resistance coacting with said means; and bearing members interposed between said elements and the shoes7 said bearing members having curved bearing surfaces on one side and fiat wedge-acting faces on the other side.

11. In a friction shock absorbing mechanism; the combination with a friction shell; of a` main spring resistance; friction shoes cooperable with the shell; relatively pivotally mounted wedge elements; adjustable bearing members between said wedge elements and the shoes; a wedge-shaped cap, disposed between and cooperating with the inner ends of said wedge elements; and spring means opposing movement of said cap inwardly of the mechanism.

1Q. In a friction shock absorbingr mechanism, the combination with a friction shell; of a spring resistance; friction shoes cooperable with the shell, a pair of pressuretransmitting wedge elements fulcrumed intermediate their ends; adjustable bearing members between said elements and the members between said wedge elements and the shoes; a wedge-shaped spring cap cooperable with the inner ends of said wedge elements; and an independent spring for said cap.

lll. In a friction shock absorbing mechanism; the combination with a friction shell having interior friction surfaces converged inwardly of the shell; of opposedv friction shoes cooperable with the shell, each shoe having a` concave bearing face on its inner side; a spring resistance for said shoes; a pair yof pressure-transmitting wedge elements fu'lcrumed intermediate their ends; bearing members interposed between said elements and the shoes and having curved bearing faces cooperable with the curved bearing faces of the shoes; a wedge-shaped spring cap-fitting between and cooperating with the inner ends of said wedge elements; and an independent spring resistance for said cap.

Inwitness 4"that I claim' the foregoing I have hereunto subscribed my name this 8th day of December, 1922.

ARILD M. BRENNE.