USRE22211E

USRE22211E - Brake mechanism

Info

Publication number: USRE22211E
Authority: US
Original assignee: Budd Wheel Corp
Current assignee: ThyssenKrupp Budd Co
Priority date: 1938-03-28
Filing date: 1942-01-31
Publication date: 1942-10-27
Also published as: GB517624A; US2228818A; US2236898A; USRE22242E; DE906102C; GB534947A; FR842076A; DE914019C; FR51183E

Description

Oct. 27, 1942. c; l.. EKSERGIAN Re 22,211

BRAKE MIECHANISM Original Filed April 29, 1939 4 Sheets-Sheet 1 u OctQ 27, 1942- c. l.. EKSERGIA Re- 22,211

BRAKE MECHANISM Original Filed April 29, 1959 4 Sheets-Shel 2 25 ATTORNEY.-

l Oct. 27, 1942. Q L. EKSERGIAN Re. 22,211.

BRAKE MEGHANISM v Original Filed April'29, 1959 4 Sheets-Sheet 3 I N VEN TOR:

CaroZaSlZE/sergz'an 'BYV , K ATTORNEY Oct. 27, 1942- c. L, EKSERGIAN Re 22,211

BRAKE MEGHANISM Original Filed April 29, 1959 4 Sheets-Sheet i.

.By a

ATTORNEY site to one another at all times.

Reuued Oct. 27, 1942 BRAKE MECHANISM.

Carolus L. Eksel-gian, Detroit, Mich., assigner to Budd Wheel Company, Philadelphia, Pa., a corporation oi' Pennsylvania Original No. 2,238,898, dated April 1,1941, Serial No. 270,750, April 29, 1939. Application for reissue January 31, 1942, Seriall No. 429,098

.26Claima The present invention relates to brakes and means for operating and mounting the same.

More speciflcally it relates to brakes oi' the type disclosed in copending application Serial No. 198,398, iiled March 28, 1938, for Brake construction, now Patent No. 2,228,818, issued January.

`In the said former design, bearings were provided on that portion of the axle between the wheels which, while entirely satisfactory in operation and construction, is a more expensive embodiment, particularly when used with live axles, and also gives rise to additional diiiiculties.

.such as the maintenance of these bearings' which are not so readily accessible because they are between the wheels and which also give rise to problems of sealing the oil against leakage. In the present construction the bearings for the vbrake structure are placed outside the wheels,

and therefore can be applied readily to standabove the arm which projects from the brake yoke, and another spring below said arm.

While in certain embodiments of the invention the cross member of the brake yoke has solid supporting arms extending fromits ends, in one yform thereof the supporting arms are also in part tubular, and such parts are made as integral bent parts of the tube forming the'cross member of the yoke.

It will be noted that the working` parts of the brake structure in accordance with the present invention are all kept alined in a single plane with the axles thus materially simplifying the structure and preventing any unbalanced strains.

The invention is disclosed in the accompanying drawings, wherein a preferred embodiment f and several variations are disclosed.

ard live axles. The bearings for the present brake supporting means lare arranged around the Journal boxes.

The present invention provides air cylinders,

I one for each brake, the cylinders being of the sin- 31e-acting type wherein only a single piston is located within each cylinder and the cylinder itself moves in the opposite direction from that of the piston, thereby requiring no equalizing means, since the forces exerted by the piston and 30 by the cylinder are in the nature of action and reaction, and thus are exactly equal and oppo- This embodiment, using single-acting cylinders and pistons, is made possible by mounting the cylinder directly on one of the brake actuating elements.

Another object of the present invention is to provide an improved mounting for the brake yoke which is supported on rubber pads or the like on a cross frame of thetruck, thus-making it possible to take up the,slight relative lateral and longitudinal motions which occur between the yoke and the truck, either absorbing them directly by the rubber in shear or. accommodating 4 them by means of a sliding contact between a steel or other metal plate vulcanized to the rubber, and the yoke bearing. The rubber also provides sufiicient flexibility to take up any stresses resulting from possible twisting occurring be- 50 tween the plane of the yoke and the plane of the cross frame of the truck.

A variation of the invention consists in employing springs in place of the rubber pads. In

In said drawings:

Fig. 1 is a plan View with certain parts shown in central axial section.

Fig. 2 is an elevation partly in section on the 'planes indicated by the broken line 2-2 of Fig.

1, looking in the direction oi the arrows.

Fig. 3 is an elevation partly in section on the planes indicated by the broken line 3-3 of Fig. l, looking in the direction of the arrows.

Fig. 4 is a detail view partly in section showing a fragment of the cross member of the truck frame and a supporting means for the end of the brass yoke, showing the arrangement of the rubber for taking up stresses.

Fig. 5 is a plan view of one half of a slightly n modiiled Wheeland brake-mechanism similar to that of Fig. 1, but wherein the tubular mem- 35 ber of the brake yoke is disposed below the plane 0 structure shown in Fig. 5 the section being madeof the brake cylinder and linkages, whereby econo'rny of space is attained, since thebrake cylinder may be closer to the wheel axle.

Fig. 6 is a partly sectional elevation of the on the planes indicated by the broken line 6-6 looking in the direction of the arrows.

Fig. 'l is a fragmentary partly sectional plan view of a still further modification, wherein the 5 tubular cross member of the brake yoke has its end portions bent to form supports not coaxial with the tubular cross member of the brake yoke itself and wherein springs are substituted for the rubber pads,.and

Fig. 8 is a partly sectional elevation of the structures shown in Fig. '7.

Referring iirst to Fig. l, l indicates a portion of 'a wheel truck in which the axle 2 is mounted, being supported by suitable roller bearings or l this embodiment there is preferably one spring 55. the like as indicated at 3, and carrying the wheels 4. Each wheelY carries a brake ring 5 of the type disclosed for example in the copending case above referred to.

A tubular cross member 8 having at each end an arm 1 extending toward the axle 2, is mounted in the truck by means of straps 8 carried by said arms 1 and is thereby mounted pivotally in the groovcd member 65 about the axis'of the axle 2, or of its journal boxes, 9.

An arm III extending in the opposite direction from the tubular member 8 and substantially in thesame general planel with the tube 6 and axle 2, extends into a support Il, Figs. 2, 3 and 4, which contains yieldable means for taking up any relative motion ybetween the axle and the truck, so as to avoid the production o! injurious stresses in the brake supporting structure.

Additional arms or projections I2, extendingv in a direction opposite to the arms 1, pass through Ayokes I3 wherein they are received with ample play, particularly in a vertical direction, so that normally7 these arms I2 are entirely out of contact with the yokes I3. The yokes I3 are secured to the truck I as shown best in Figs. 2 and 3. by means of the stems I4 which have screw threads I5 thereon and pass through lugs I8, with nuts I1 to secure tiem to the frame of the truck. y The yoke I I which receives the arm I I! is secured to the truck I by means of two upwardly extendirg stems I8, having threads I9 thereon, whch pass through the cross vmember 20 of the truck and are secured thereto by the nuts 2|, a bfarinfr nleteZ and'suitablelock washers 23 prcierablir boing provided. as best shown in Fig. 4. The above mentioned arm III is preferably made hollow for lightness as shown best in Fig. 4 and it may rest between steel and other metal plates 24 which are in turn vulcanized to rubber plates 25. the arm I having

projections

25 and 21, at its end, and spaced somewhat from its end, respectively, to-hook over the steel plate and part of the rubber in order to prevent longitudinal shifting of the said steel and rubber plates along the arm I0'. In this way the rubber plates, which are arranged above and belowrthe end of the arm I Il, provide for a yieldable mounting of.

the said arm and prevent any undue stresses from being produced by relative motion of the brake mounting and the truck while yet preventing rotation of the brake mechanism about the axle 2.

In order to apply a braking effortr to the brake rings 5, the annular-

arcuate brake shoes

28 and 29, cooperating with each of said rings must be forced thereagainst and this is accomplished by two alternative means, one being the air braking system and the other the hand brake linkage or emergency service system. It will be noted that each brake shoe 28 is pivotally attached at 39 to a corresponding lever 9|, pivoted at 92 to a bracket 33 secured to the tubular member 8. the other end of each lever 3| being attached to an air cylinder 34 by any suitable means such as the cap screws 35. so that when the two cylinders 34 move toward Aone another the brake'shoes 28 will be fo-rced outwardly against their respective brake rings -due to thepivotal motion of the levers 3I about their relatively nxed pivots 32.

The 'brake shoes 29 which cooperate with the outer surfaces oi' the brake rings 5 are similarly pivotallyattached at 36 to the inner ends oi' the levers 31 which are pivotally mounted at 38 onV the same brackets 33, the levers 31 terminating at their far ends in pivotal mountings 39 carried by connecting rods 48 pivoted at 4I to Pistons 4l operating in the respective cylinders 94.` It will thus be seen that when the pistons 42 move outwardly in their respective cylinders 94 they will cause the pivots 39 to move outwardly, thereby turning the levers 31 about their relatively fixed pivots 38 and causing the brake lshoes 29 to move inwardly. Thus when air is admitted to the cylinders 34 through the ports 43 which are connected to any suitable flexible air supply means, not illustrated, the. result in each case will be that the brake shoes 28 and-29 will be forced againstthe opposite sides of the corresponding brake rings 5 due to the relative motion of they cylinder and piston in each case and moreover the braking efforts produced on vboth sides of the brake ringwiil be equal, since the mounting of the levers 9| and 91 provides for free equalization oi' the forces applied by the cylinder and piston respectively, which of course themselves are equal ab initio.

In order to make it possible to operate the brakes in case of failure of any part of the air outside of the brake system, an emergency hand brake is'provided which comprises the link 44 to which the brake rod is attached by means ofthe hole 45 at the mid point of the link 44. The link 44 has a pivot 46 at each end thereof on which ispivotally mounted a short link 41 which is in turn pivoted at 48 to the long arm of a bent lever 49 pivoted at 5U to the respective lever 3| which operates the internal brake shoes 28. The short arm of the lever 49 is pivotally connected at 5I to a link 52 having a slot 59 at its other end, engaging slidably as well as plvotally about a pin or pivot 54, mounted on therespective lever 91 which actuates the corresponding outer brake shoe 29;

It will be seen that whena pull is exerted upon the brake rod (not shown) attached to the link 44 it will have the ultimate eiiect of tending to straighten the toggle linkage formed by the short arm 55 oi the lever 49 and the link 52, thus forcing the long arms of the levers 3I. and 31 apart without however acting more forcibly on one than on the other, because the, short link 41 will permit equalization in each case. It is thus clear that a pull on the hand brake rod will apply all four brake shoes with equal force. When the hand brake rod is not actuated, the slotted portion 53 oi' each link 52 will permit free movement of the air brake structures, entirely independently of the hand braking means.

In normal operation the arm I 9 will be supported in the surrounding yoke II, but in case the arm I8 or the supporting yoke I I 'should fail by reason oi' breakage, the arm I2 will then still holdthe brake mechanism in proper operative position because the yokes orfsafety hangers I9 will then come into play and prevent the brake mechanism from dropping. A

It will be understood that the arms 1 together with their straps 8 are pivoted about the grooved member concentric with the axle 2 so that the tube 8 may pivot slightly about the axis of the said axle. which thus permitsV the tube 8 to assume the proper position and avoid undue stresses while at the same time the straps 9 permit ready removal of the entire brake structure, upon merely removing the fastening nuts 85. The brake yoke is not secured positively to the truck I at any other places than by means of the two arms 1 and their mountings and these elements are readily accessible since they are wheels, thus making it easy to Figs. andv 6. this formof :tional economy of space.

the mechanism orto remove it spection 4or repair.

Referrin how for in to the modioation shown in device provide addi- This economy is at.

'I indicates the truck having the journal boxes l in which the axle, 2 is mounted. This axle carries the wheels l and brake rings l with which cooperate the internal and external brake shoes 2l and 2l respectively, which are carried by the levers` II and ll. A bracket I4 secured to the tubular support 6 has a pivot 32 about which the lever ll moves and a pivot 38 for the lever 59. 'I'he respective levers are pivoted to the brake shoes at 3l and IB at their short ends, and at their long ends they are attached respectively to the corresponding cylinder 34 and the piston rod lll, which is pivoted at l.

An arm Il which is inclinedas shown connects the tube l with its bearing 8i around a portion of the journal l andthe connecting strap B serves to secure it in place. A- horizontal arm i2 projects rearwardly from the tube B and is supported loosely in the yoke Il, which is held to the truck by means of the support l0 having a screw threaded end Il. received in the lug 6l of the truck and secured thereto by means of the nut In place of the straight arm il which extends centrally fromjthe tube l inthe rst described form, here an upwardly inclined arm 51 is substituted, which accomplishes the same function. that is, it is supported at its end in the yoke il, with yieldable cushions interposed as in the previousLv described form. The. yoke II is secured to the cross member 20 of the truck I by means oi' 'the rods il which are screw threaded at Il and held to the bearing plate 22 resting on the cross member 2l by means of the nuts 2|, just as in the other form. The 4bracket 84 which takes the place of bracket 28 also is inclined upwardly as shown, and supports the pivots of the relatively

shorter levers

68 and 59 which replace levers 3l and l1 of the first-described form.

The operating means for the hand or emergency brake is precisely the same as that-employed in the previously described form and its elements are designated by the same reference characters. It will be understood that the parts shown in Fig. 5 are duplicated symmetrically on the other side of the horizontal centerline frm- `ing the upper boundary of Fig. 5.

A modified form of device shown inl Figures `7 and 8 attains certain advantages of simplicity and compactness in a somewhat diil'erent way.

In this form of the invention the yoke member l1, corresponding to member B of the preceding forms, is made in the form Yofa tube with offset or "cranked" ends, as at 68. That is, at each end additionally economized, a very important feature in the limited room available.`v

'Ihe yoke element O1 may have its ends some- -3 what reduced in diameter as shown at Il and these reduced portions will be received in the tubular ends 1li of the supporting arms 1, to which they are secured by suitable welds, as at 1l and 12, so as to constitute substantially a single rigid integralv element with said arms.

vThe arms 1 are pivotally\supported from the journals by. means of straps B, as previously described.

A cylinder 34 is located near each end of the 'yoke member 81, 'and is provided with a piston.

as inthe other forms, previously described. Each cylinder is attached as by bolts and nuts 3i to one arm of a lever-13, pivoted -at 32 to a lug 14, preferably integral with the tube 61 so that when the cylinder moves toward the longitudinal. center line of the truck, the other arm of its lever 13 will move outward, so as to force the brake shoe 28, pivoted thereto at 30, against a brake surface of the brake ring 5.

The connecting rod Iii, attached to the piston in cylinder 24, simultaneously will force outward the adjacentl arm of lever 15, pivotaily mounted at l. in the lug 1l, so that the other arm of said lever, acting through the pivot pin 38 which connects it with the other brake shoe 29, will force shoe 28 against the other brake surface of the brake ringl. thus engaging both faces of said lring between the two shoes 2l and 28. Since these shoes are actuated by cylinder and piston respectively, they, of course, will engage the ring with equal force on both sides, thus distributing the braking effort uniformly thereon.

The brake yoke may be prevented from turning about the axis of axle 2 by means of the outwardly extending arm 16, engaging a support carried -by the cross member 2li ofthe truck frame. While this arm '16, which is preferably integral with the tubular member 81, might be supported by rubber pads or similar resilient material, like arm III of Figure 1 for example, a different type of resilient and yieldable suspension is here disclosed. This suspension avoids all use of rubber or other organic material, and is, therefore, in some ways more resistant to -destructive agentsy which would eventually injure rubber and the like, such as chemical impurities in the air, moisture, excessive heat, etc., which may sometimes be encountered in service, and which, would tend tb harden and age rubber and similar substances prematurely.

In Fig. 8

helical metallicsprings

11 and 18 are disclosed. vThe springs are mounted in a casing which may advantageously comprise an upper section 19,'secured to thecross beam 20 of the truck by a ange 8| and bolts B2 and 83 and a lower section lBil, the sections being removably' .held together by bolts 84 in cooperating flanges 85. Lugs 8B and 81 in the respective sections serve to prevent the outer ends of the springs from slipping out of the casing, and their inner ends are kept in proper relation to the end of the arm 18 by circular flanges B8 formed thereon.

The original inserting of the springs in their casing, as well as any necessary subsequent removal or insertion of springs, is made easier by reason ofthe two part construction of the casing, since removal of the lower section by unscrewing the bolts 84 will give ready access to the contents of the said casing.

In order to avoid mis-alignment between the springs and the end of the arm 1B, the said end is preferably made as a separate element $9.'

pivotally supported in a fork 90, 9| formed on the arm 16, a suitable pin l2 passing through the suitable evice, here shown as a bolt 99 passing through hole in the element 89 and engaging ina notch 94 formed in the side of the pin 92.

The hand-operated or-emergency brake linkage may comprise' the following parts: A lug 95 preferably is formed on the tube 81, and vextendstoward axle 2, to afford a suitable support for lever 99, whichy is pivotally held by pin 96, mounted in lug 95 and secured against loosening by any'suitable locking device, such as the cotter pin 91.

Each linkv has at its other end a pivot |01,

' whereby it is attached to the inner end of its respective lever |06. Each lever |00 is pivoted at'.A |00 to the corresponding adjacent lever 19 and is bent sharply at the said pivot as shown, to provide a relatively short arm extending toward the axle 2. At its end, each of the said arms has a slotted portion, |09, which receives the pivot pin ||0 attached to the link which link is also pivotally secured to the lever 'I5 as shown at H2. The slotted portion |09 thus serves as a lost-motion device, whereby the

levers

19 and 15 may operate freely under .control of the air brake cylinder and piston, without restraint by the manual brake operating parts. n

The operation of the devices disclosed in Figs.

1 to 6 of the present case will beclear from the structures described but may be summarized briefly as follows:

1 When air under pressure is applied to ,the cylinders 34 the result will be that the

brake shoes

29 and 29 will be forced against the opposite vsides of the brake rings 5, the pressures being completely equalized by reason of the fact that the pressure on one side is produced by the pis. ton, while that on the other side is produced by the corresponding cylinder, which of course are identical in magnitude. By reason of the fact that the whole assembly of cylinder and'piston is freely movable about the

pivots

32 and 38 the brake shoes are free to adjust themselves against the, brake rings so that nothing can interfere with such equalization.

k By reason of the fact that all the air cylinders are identical and supplied from a common source of air, all the pressures will of course further be equal to one another, that is, thepressure exertedl on the brake rings carried by the right and left hand wheels automatically will be the same, even though `this may not be an important feature. `Any stresses which might otherwise result from binding, in case there were a rigid connection between the brake yoke and the truck frame, are completely eliminated by reason of the yieldable mounting of the rear arm I0 of the brake yoke, wherein the available distortion of the rubber etc. as well as the available sliding movement entirely eliminate any such stresses.

The arms |2 extending from the tubular member l and carried in the yokes Il, but out of contact therewith, provide a safety feature in case the arm I0 should fail for any reason, since the yokes Il would then support the braking mechanism until repairs could be made.

In the form shown in Figs. 5 and 6 the operation is, oi course, the same as in Figs. 1 to 4, the

only dierence being that this form of device is made more compact in a forward-and-back directlon, by placing thetubular brace 8 below the horizontal plane containing the axes of the axle 2 and of `the braking pistons, and, therefore, the same operative features as those above described will apply to Figs. 5 and 6 also.

The operationof the form illustrated in Figs. 'l and 8 is of course practically the same as that of the previously described forms. The bends near the ends of the tubular member 91 bring its central portion closer to the axle 2 than would otherwise be possible, thus resulting in economy of space and permitting a material shortening of the trucks, by shortening the levers 1l and 1l andalso by bringing the cylinders Il closer to the axle of the wheels.

Air pressure in the cylinders 94 will force each piston out of its cylinder, thus causing the `brake shoes to engage the opposite faces of the rings l with equal force in each instance. A pull on the manual brake rod engaged in the hole |0| of the lever 90 will cause the equalizing lever |09 to move toward axle 2, thereby applying equal pulls on the two links' |05, and thus on the long arms of the two levers |09, whereby their short arms, in combination wtih the links will form toggles acting to separate the corresponding ends of the levers 13 and l5, so as to cause the brake shoes to engage the respective brake rings l. When the manual brake is inaction, the pins ||0 will lie against one end oi' the slots |09, while the same slots will permit lost motion to occur when the air brake cylinders are used. as already mentioned above. f

The metal springs 11 and 18 will provide a yielding support for the` outer end of the lever 16 so as to hold it in proper position, while taking A up any sudden iolts or shocks, or slight differported thereby until repairs could be made, thus protecting the vehicle against loss of braking on failure of a spring. It will be seen that the wholly metal construction resulting when metal springs are employed in place of rubber pads or the like has certain inherent advantages, such as better resistance to chemically active gases ror solvent liquids, as well as resistance to the aging effects ofair, light, and heat, all of which are well known enemies of rubber.

In all of the forms the operation of the emergency brake in no way interferes with the operation of the air brakes, since play is available in the slotted links or lever arms of the hand brake.

While several forms of the brake Amechanism have been disclosed and described in detail, it will of course be understood that many other modifications are possible and that, therefore, the scope of the present invention is limited not by the disclosure but only as defined in the following claims. Y

I claim:

1. A brake mechanism comprising a wheeland axle, a brake ring connected therewith, brake shoes in cooperative relation with the opposite faces ofthe said ring, a brake yoke pivotally supported about the axis of the axle, means for preventing the` yoke from turning about the'said axis, and pressure-fluid actuated mechanism carried by the brake yoke, comprising two members movable in opposite directions, and connected one concentric with the axle at points outside the the axis of the axle, and that of the cross piece b being in the same plane, but the axis of the iluidpressure actuated mechanism being located to.

one side of the said plane.

2. A brake mechanism comprising wheels and an axle for the same, a brake ring connected therewith, brake shoes in cooperative relation with the said ring, a brake yoke, the said-yoke including a cross piece having end portions which are oifset adjacent the wheels, to clear the same, whereby the cross piece is located nearer to the axle, pressure-fluid actuated mechanism supported by the cross piece, for operating the said brake shoes, said mechanism being located between'the offset portions, so as to bring it closer to the axle, means attached to the outer ends of the cross piece and pivotally supporting it about the axis of the axle, and means for limiting the extent to which the yoke can thus turn about the said axis.

3. A brake mechanism comprising wheels and an axle for the same, a brake ring connected therewith, brake shoes in cooperative relation with the said ring, a brake yoke, the said yoke including a tubular cross piece having tubular end portions, which are offset adjacent the wheels to clear the same, whereby the cross piece is located nearer to the axle, pressure-fluid actuated mechanism supported by the cross piece, for operating the said brake shoes, said mechanism being located between the oiset portions, so as to bring it closer to the axle, means attached to the outer ends of the cross piece and pivotally `supporting it about the axis voi the axle, and

.the aperture thereof, resilient blocks above and below the said arm, respectively, filling the -spaces .between the saidiarin and the top and bottom of the aperture, to prevent lost motion of the said arm with 'respect to the frame, and

a second apertui'ed member on the frame, the other arm jextending into the aperture thereof. but being out of contact with any vportion of the said second member.

5. A brake mechanism comprising a wheel and axle assembly, a brake ring connected therewith,

brake shoes in cooperative relation with thel op'` posite faces of said ring, a support for said shoes comprising a yoke extending laterally beyond the wheels and pivotally supported about the axis of the axle outside the wheels, means to prevent the yoke from turning' about the axis, and fluid pres'- sure means carried by the yoke andI connected to actuate the shoes. Y

6. A brake mechanism comprising a wheel and axle assembly, a brake ring connected therewith, brake shoes in cooperative relation with the opposite faces of said ring, a support for said shoes comprising a transverse beam arranged substantially in lthe horizontal plane of the axle and extended between the wheels and laterally therebeyond and supported at its ends for movement wheels, means for preventing the yoke from rotating about said axis and iluid pressure means carried by the beam and connected to actuate the shoes.

7. A brake mechanism comprising a wheel-'and axle assembly, a brake ring connected therewith,

brake shoes incooperative relation with the opposite faces of said ring, a support for said shoes comprising a generally horizontally disposed yoke including a transverse beam extending laterally beyond the wheels and pivotally supported about the axisof the axle outside the wheels, and means for actuating said shoes carried by said beam and including an actuating cylinder, said cylinder and the ends of said beam being arranged with portions thereof disposed-in the same vertical transverse plane, whereby to foreshorten the brake mechanism in the horizontal plane.

8. A brake mechanism comprising a wheel and axle assembly, a brake ring connected therewith,

brake shoes in cooperating relation with the op-V posite faces of said ring, a support for said shoes comprising' a yoke including a transverse beam extending across and beyond the wheels and pivotally supported about the axis of the axle outside the wheels, means preventing rotation of the yoke about said axis, the portion of the- 9. A brake mechanism comprising a wheel and axle assembly,y a brake ring connected therewith, brake shoes in cooperative relation with the opposite faces of said ring, a generally horizontally disposed yoke support for said shoes extending between andv beyond the wheels and pivotally supported about the axis of the axle outside the wheel, means for preventing rotation of the yoke about the axle, and safety means associated with said yoke to prevent dropping of the yoke in the event of failure of said `rotation preventing means.

10. A brake mechanism according to claim 9 in which the yoke comprises a transverse beam extending between and beyond the wheels, and separate safety means are associated ywith each end of said beam.

1l. A brake mechanism comprising a wheel and axle assembly, a Drake ring connected therewith, brake shoes in cooperative relation with the opposite faces of said ring, a support for said shoes comprising a yoke supported at opposite endsl brake shoes pivotally associated with the axle,

' to said support throughbperating levers one means for preventing rotation of the support about the axle; the brake shoes being connected associated with each shoe, and an actuating cylinder an'd piston disposed between saidV levers, said cylinder belng'rigidly xed to one of said levers, andthe piston being connected to the other of said levers.

13. A brake mechanism comprising a wheel and axle assembly, a truck frame supported thereby for relative vertical movement with respect thereto and having' a transverse member, a

brake-carrying. yoke pivotally supported about the axis of the yaxle including a cross beamgenerally paralleling the axle and having an arm extending centrally therefrom, va readily detachable bracket rigidly' secured tosaid transverse member. and having an aperture receiving the end o r said arm whereby to prevent turning ci the yoke about said axis.

14.4 A brake mechanism according to claim 13 in which resilient means are arranged between the arm and the top and bottom walls o! said aperture, respectively, and the bracket overlaps thel top ot said crossy member.

l5. -A` brake mechanism according to claim 13 in which the end of the arm is forked and a spring abutment is pivotally supported between the forks, and springs interposed between said abutment and the top and bottom walls of said aperture, respectively.

16. A brake mechanism according to c1aim13 in which resilient means are arranged between the arm and the top and bottomy walls of said aperture, respectively, the bottom wall being detachable from `the top wall to facilitate assembly and disassembly.

17. In a railway truck or other vehicle having a frame and a wheel and axle assembly. brake mechanism comprising a brake ring connected to rotate with a wheel o! said assembly, brake shoes in cooperative relation with said ring, a brake yoke carrying said shoes, said yoke including a transversely. extending beam having end portions which are odset adjacent the wheels I said assembly, to clear the same. whereby the vintermediate portions oi.' said beam between the i wheels is located nearer to the axle, pressureuid actuated mechanism supported by said beam, for operating the shoes, said mechanism being located laterally between the oilset end portions oi the beam, so as to bring it closer to the axle, said yoke support being connected to the truck by a pair oi articulated connections disposed outside the respective wheels of said wheel and axle assembly and on a common transverse axis serving as a iulcrum in the'region o1' l the wheel and axle assembly and by another connection radially remote from said axis and serving to react against the `braking torque.

18. In a railway or other vehicle truck having a -wheel and axle assembly and a brake mechanism associated' therewith, said brake mechanism comprising a disk-like brake ring associated with each wheel of said wheel and axle assembly. brake shoes in cooperative relation, respectively, with a lateral face of each oi said rings,l

actuatingl levers carrying the respective shoes', anda support Ior said shoes and levers compris- Y jacency to each wheel of said assembly, seg- A port for said beam disposed laterally interme- V diate its ends and radially remote from said axis,

said third pointof support serving to react againstV the braking torque, and iiuid pressure means carried by said beam and connected to -actuate the shoes.

20. In aV railway truck or other vehicle having a frame and a wheel and axle assembly, brake mechanism comprising a brake yring connected to rotate with a wheel of said assembly, brake shoes in cooperative relation with the opposite faces of said ring, a support for said shoes comprisingA a generally vhorizontally disposed yoke including a transverse beam extending laterally beyond the wheels and pivotally supported cutside the wheels of said assembly for movement about a transverse axis serving as a fulcrum longitudinally in the region of the wheel and axle assembly, and means for actuating the shoes carried by the beam and including an actuating cylinder, said cylinder and the end portions oi the beam in the plane of the wheels being arranged with portions thereof disposed in the same vertical transverse plane.

21. In a railway truck or other vehicle having a frame and a wheel and axle assembly, brake mechanism comprising a brake ring connected to rotate with a wheel of said assembly, brake shoes in 'cooperating relation with the opposite races of said ring, a support for said shoes comprising a yoke including a transverse beam exing a yoke extending laterally beyond the wheels and supported through laterally spaced articulated connections lying on a common transverse i axis serving as a fulcrum for said yoke and being disposed laterally outside the wheels and longitudinally in the region of the wheel and axle assembly, and another articulated connection disposed transversely intermediate said laterally spaced connectionsand radially remote from said transverse axis thereof Iand serving to react against the braking torque, said articulated connections as a group aiording relative movements 4between said yoke and the truck without imposing undue stresses upon said yoke.

19. In a railway or other vehicle truck having a frame and a wheel and axle assembly, brake mechanism comprising a pair oi brake rings, one secured to rotate lwith and disposed in close adtending across and.v beyond the wheels of said assembly and pivotally supported at laterally spaced points outside the respective wheels on a transverse axis serving as a iulcrum and disposed in the region ot said wheel and axle assembly, means preventing rotation oi' the yoke about said axis under the braking torque, the

portion of the beam between the wheels being oiset toward the axle, and actuating levers tor the shoes pivotally mounted on the oiset portion and in close adjacency to the periphery of said vbrake ring,

22. In a railway truck or other vehicle having a frame anda wheel and axle assembly, brake mechanism comprising a brake ring rotatable with a wheel of said assembly, brake shoes in cooperative relation with the opposite faces oi said ring, a generally horizontally disposed yoke support for said shoes mounted to iulcrum about a transverse axis in the region of the wheel and axle assembly and having means for preventing rotation of the support about' said axis under braking torque, and safety means associated with theyoke to prevent dropping of the yoke in the event of fuilure of said rotation-preventing means.

`23. In a railway or other vehicle truck having a i'rame and a wheel and axle assembly. brake mechanism comprising a disk-like brake ring connected with, and4 disposed in close adjacency to, each Wheel of said assembly, segmental brake shoes in cooperative relation, respectively, with each ofsaid brake rings, actuating levers carrying said shoes, and a support for said shoes and 'longitudinally on levers comprising a yoke connected to the truck by'spaced articulated connections, a. pair of said connections being disposed laterally outside the wheels of said wheel and axle assembly and longitudinally in the region of said assembly, said pair of connections having a common transverse axis serving as a iulcrum, the intermediate portion of said yoke having a third articulated connection with the tru'ck radially remote from said axis and serving to react against the braking torque.

24. In a railway or other vehicle truck having a frame and a wheel and axle assembly, a brake ring connected with, and disposed in close adjacency to each wheel of said assembly, brake shoes each carried by an actuating lever in cooperative relation with each of the opposite faces of said ring, a support for said shoes and their actuating levers having spaced articulated connections with the truck, a pair of said connections being laterally disposed outside the Wheels and a common transverse axis serving as a fulcrum disposed in the region of the wheel and axle assembly, and a third of said connections being radially spaced from said axis and serving to react against the braking torque.

\ 25. In a railway truck or other vehicle having a frame and a wheel and axle assembly, brake mechanism comprising a brake ring` rotatable with a wheel of said operative relation with the opposite faces of said ring, a support for said shoes movably mounted to fulcrum about a transverseA axis disposed in the region of the wheel having means for preventing rotation of the support about said axis under braking torque, the brake shoes being connected to said support through operating levers, one associated with and axle assembly and assembly, brake shoes in co- `spaced each shoe, and an actuating cylinder and piston disposed between the levers, said cylinder being rigidly fixed to one of said levers, and the piston being connected to the other of said levers.

26. In a railway or other vehicle truck having transversely joined side frame members interconnecting longitudinally spaced wheel and axle assemblies, brake mechanism associated with at least one of said wheel and axle assemblies and comprising disc-like braking members one associated with and being disposed closely adjacent to each wheel of said assembly, segmental brake shoes lying closely adjacent the respectivewheels and adapted to cooperate, respectively, with said disc-like braking members, actuating brake levers carrying said shoes, respectively, and a unitary rigid brake support comprising a transverse beam extending laterally from wheel to wheel of said assembly and therebeyond and carrying said brake shoes and brake levers, said support having longitudinally and laterally spaced articulated connections with the truck aifording relative movements between said brake support and the truck, without imposing undue stresses upon said brake support, a pair of said connections lying on a common transverse axis serving as a fulcrum for said bra-ke support and being disposed laterally outwardly beyond the wheels of said assembly and longitudinally in the region of the wheel and axle assembly, and another of said connections being disposed laterally intermediate said pair of laterally spaced connections an'd radially removed from said transverse axis thereof and serving to react againstthe braking torque.

CAROLUS L. EKSERGIAN.