US2146909A - Brake shoe - Google Patents

Description

AA NELSON Feb. 14, i939.

BRAKE SHOE Filed Feb. l, 193'? ll n Patented Feb. 14, 1939 UN ITED .1S TAT'ES BRAKE sHoE y Albert Nelson, Chicago, Ill., assignor to' The American Bralie Shoe and Foundry Company, New York, N. Y.,Va.=corporation of Delaware. a

Application February, 1, 1937 Serial No.Y 123,345 f 1 Claim.

This invention relates to certain novel improvements. in brake shoes rof the :kindV used Aon railway equipmentandmore particularly tocast metallic shoes-adapted for such usage.

A brake shoe'oiA .the kind to which this invention pertains is substantially rectangular in plan and of arcuate shape longitudinally yand is provided on its back midway between its ends Witha center attaching lug and at its ends on its back with what 10 are called end stops. This lug and `these stops cooperate with ycomplementary parts on .a head that is part of the brake rigging when the shoe is keyed or .otherwise secured to. the head to; retain the shoe in operative position and -to Ethis end l the inwardlydisposed faces of 1the 4end'stops are spaced y'from the .center l attaching lug in an amount specified by'present A.` R. A. regulations.

The longitudinal thrust on the shoe in a `braking operation eiTected -by engaging the wearing 20 face of the shoe with vthe tread of the Wheel sis for the most; part impressed on the-end stops which also serve to prevent sidewise movement ofthe shoe in the head. It will therefore beappreci-ated that the end stops are subjected to severe strains 25 in use.

Furthermore it is customary to chill the ends of a lora'ke shoe, especially on the wearing face, as it is cast, wherefore the ends of the shoe underlying. the end stops yare rendered :more frangible 30 than the other portions of the shoe. It is vtherefore an advantage to provide substantial end stops at the ends of the Vshoe 'for so to do affords reenforcement for the more frangible portions and mitigates against fracture f and vkindred 35 damage.

` Thus relatively 'large end stops are desirable but the Xed-dimensions of the partsof the head with lwhich :the stops cooperate whenthe shoe is installed, requiring spacing of the inwardly disposed faces of the end stops from the center vattaching lug in an amount specified by present A. R. A. regulations, prevent enlargement of the stops inwardly of the shoe. It is of cours-e possible to increase'the size of the stops outwardlyof the shoe but so to do longitudinally would ordinarily require lengthening of the over-all length of the shoe especially on its wearing face. This, however, would be objectionable for several reasons not the least of which would be that such procedure would require larger flasks than are now employed'in the casting of shoes. Makers of brake shoes have on hand a very large number of iiasks suitable for shoes ofthe present wearing V55 face length and such 'flasks would be rendered (Cl. 18S-258) uselessif a shoe having a longer .wearing face .than the present shoe was vto beY cast. l

Thusin View of the foregoing the salient object of this invention is to enlarge the end stops customarily provided, on abrake shoe, .especially longitudinally of the shoe, Without increasing the length of the Wearing face ofthe shoe. Y y

A reenforcng back Acustomarily in the form of `a steel plate :is often provided at the back of a brake shoe and a'lbundleof `expanded metal is often incorporated in such a shoe. To insure the iiow of suiiicient metal past the ends of such back and bundles to form Ythe end stops, such backs and bundles are terminated .inwardly of the-ends of the shoe with the result that thereenforcing backs .usually project but a very short distance under theend stops which as .av result are'not as effectively reenforced by the back as `they would beA if `the backprojected .thereunder fora substantial distance.

Therefore still .another object of this invention Y is sto enablev the reen-forcing back customarily provided in a brake shoe toI be projected well toward theends of the shoe so that Ait Willunderlie and effectively reenfo-rce the end stops provided on the backl of the shoe at lits ends, and an ancillarylobject istoafford anchorage through the back for theend stops.

Other objects are included inthe following descriptioh wherein reference is made to the accomparlying drawing in which Fig. 1 is a side elevation of a brake `shoe `made in accordance with my invention;

Fig 2isa^top plan ofthe shoe shown in Fig. l.;

Fig. ,.3 isa vertical transverse sectional detail View 'taken substantially on 4the line 3--3 on Fig. 2;

Fig. 4 isa horizontal sectional detail View taken substantially on theline 4-4 onFig. 3; n

'Fig..5 is a fragmentary viewsimilar to Fig. 1, showing the endfof astandard brakeshoe; l

Fig. 6 is a fragmentary top planvof a modified formof. a reenforcingback and wherein the outlines of a brake shoe' embodying such back are shown in broken lines; and y Fig. '7 yis a fragmentary view, similar to l, ofa shoe embodying the back illustrated in Fig. 6.

'My novel shoe as illustrated in the .accompanying drawing comprises a body 'B preferably of cast ironandhas a reenforcing back l preferably 4in the form of a steel plate embedded `therein at the rear face thereof. As best shown in Figs. 1 and vr2 the sho-e is ysubstantially rectangular in planand ofarcuate shape longitudinally toprovide a wearingfface at its yfront adapted vto cooperate with the tread of a wheel in a braking operation.

Midway between its ends and on its rear face the shoe is provided with a center attaching lug 8 in the form of a steel strap bent toprovide vertically extending legs which project through openings in the back 'I and have their ends inturned toward each other to thereby connect the strap to the reenforcing back. Preferably the body is extended upwardly to enclose the side edges and outer faces of the vertically extending legs of the strap providing the attaching lug 8. A portion 9 of the body is extended betweenthe adjacent faces of said vertically extending legs immediately above the reenforcing back I to reenforce the portions I0 (Fig. 4) of the body'outwardly of the side edges of the vertically extending legs to prevent breaking away of these portions I Il. An opening defined by the strap 8 and the upper wall of the portion 9 is of sufficient size to enable a key or other attaching means to be passed therethrough to secure the shoe in operative position in the usual head that is a part of the brake rigging of railway equipment.

At each end and on its back the shoe is provided with substantially T-shaped end stops II, the stems I2 of which extend inwardly of the shoe substantially midway between the side edges thereof. These end stops are disposed in such positions on the back of the shoe that the inwardly faced edges of these stops are in position to properly cooperate with the head when the brake shoe is placed on the head and to this end the inwardly disposed faces of the end stops are spaced from the center attaching lug in the amount specified in present A. R. A. regulations. It has been customary to provide openings as I3 in the reenforcing backv 'I so thatthe metal providing the stems I2 will be united with the body of the shoe by a section of metal in these openings I3. This arrangement affords reenforcement for the stems I2 of the end stops but the branches or cross members of the end stops on which most of the thrust is impressed in a braking operation are not materially reenforced by this arrangement. Y

Thus it is proposed to enlarge the cross rmembers of the end stops I I soas'to strengthen these members and consequently kthe endvstops as a whole, and in the present instance this has been done by elongating the end stops longitudinally of the shoe. Y

It has been explainedthat it is objectionablato elongate the wearing face of ra brake shoe and thus in my novel shoe, even though the end stops are elongated, elongation of the wearing face is avoided by alteration of the ends ofthe shoe, the standard arrangement for the'ends of a shoe being shown in Fig. 5. By referring to Fig. 5 it will be seen that the end of the standard shoe lies in a plane extended in angular relation with respect to the face of the shoe, the angularity between the end and the face of the shoe being materially less than a right angle.

In contradistinction to this in my novel sho a part of the end of the shoe lies in a plane extended from and in substantially right angular relation with the wearing face of the shoe for an appreciable distance away from the wearing face of the shoe, that is to say, to a position disposed a short distance below the plane of the back of the shoe. The remaining part of the end of the shoe is then arranged to lie in an inwardly extending plan-e, the outer ends of the end stops also lying in this plane. Thus the end of the shoe lies at the end of the shoe, with the inwardly disposed faces of the end stops in the position specified by present A. R. A. regulations, without an increase in the length of the wearing face of the shoe and with but a very small increase in the over-all length of the shoe wherefore elongation of the end stops is accomplished, but the objections which would be attendant to an increase in the length of the shoe, especially at its wearing face, such as rendering present flasks useless, are avoided. Y

By referring to Fig. l wherein a reenforcing back of a length corresponding to that employed in a standard shoe is shown, it will be noted that there is appreciable metal between each end of the back and the adjacent'end of the shoe. In fact, substantially twice as much metal as ordinarily provided is present as will be seen by comparison of the shoe in Fig. l with that shown in Fig. 5. This affords veryy firm anchorage for the end stops and substantially increases the strength thereof.

However, as shown in Fig. 7, it is possible to use a back longer than is customary in my novel shoe, and thereby reenforce the end stops, and when such a longer back is provided it is arranged to-terminate in spaced relation with the ends of the shoe in an amount substantially equal to the spacing of the usual back from the ends of a standard shoe. This spacing enables sufficient metal to flow past the ends of the back in the casting operation to insure proper formation of the end stops.

However, when such elongation of the back is resorted to, it is preferable and advantageous' to afford additional reenforcement for the endstops and this may be accomplished by providing an opening as I3 in the elongated back indicated by I4. The longitudinally elongated openings I3 are located in the back` I4 impositions similar to the location of the openings I3 in the standard back 'I. YBut in addition to the openings I3', longitudinally elongated openings I5 may be provided at each side of the openings I3'. f The openings I5 will underlie the cross or branch members of the end stops and will afford anchorage for these members inasmuch as the stops will be united with the body of the shoe by metal extending through the openings I5.

It will therefore be seen that substantial' or enlarged end stops may be provided on the back of a brake shoe at its ends without elongation of the wearing face of the shoe or substantially est increasing the over-all length of the shoe and Furthermore,

the end stops but by providing openings in such a back firm anchorage through the back for the end stops may be afforded especially by properly locating the openings in the back.

Furthermore, such enlargement of the end stops is accomplished in accordance with my invention by Varying the formation of the ends of the brake shoe and instead of arranging the ends in single planes extending at acute angles with respect to the wearing face of the shoe they ends are arranged in two intersecting angles, the apex between which is disposed somewhat below the plane of the back of the shoe, and one of these planes is arranged to extend substantially at right angles to the wearing face of the shoe and the other plane is arranged to project inwardly from such right angularly extending plane at a relatively large obtuse angle.

While I have illustrated and described a preferred form of my invention it is to be understood that this is capable of variation and modification and I therefore do not Wish to be limited to the precise details set forth but desire tol avail myself of such changes and alterations as fall within the purview of the following claim:

I claim:

A brake shoe having a center attaching lug on its back midway between its ends and end stops on said back at the ends of the shoe, each of said end stops being substantially T-shaped in formation and having the outwardly dispo-sed end thereof lying in the adjacent end of the shoe and having the inwardly disposed faces of the branches thereof spaced from the center attaching lug in the amount specified by present A. R. A. regulations, each of the ends of the shoe having two anguiariy disposed faces, one of the faces at each end of the shoe extending from the wearing face in substantially right angular relation with said wearing face and the second of the faces at eacn end or' the shoe extending inwardly of the shoe at substantially a 165 angle with respect to the other face whereby the branches of the end stops are of substantial size, and a reenforcing back embedded in the shoe at its rear face and having the ends thereof spaced inwardly but a short distance from the intersection of the faces at each end of the shoe, said back having an opening therein at each end thereof disposed entirely beneath the stem of the adjacent end stop and other openings therein respectively positioned on opposite sides of the first openings, said other openings being disposed partly beneath the branches of the end stops and in transverse alignment with the first openings, the body of the shoe being united with said end stops through said openings, the angular inclinations of thefaces of the ends of the shoe, the extension of said back beneath the end stops and the connection of said end stops with Vthe body of the shoe through said openings effectively reenforcing said end stops.

ALBERT NELSON.

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