US2250637A - Brake head wear element - Google Patents

Description

y 1941. M. s. JoHNsoN 2,250,637

BRAKE HEAD WEAR ELEMENEI' Filed Feb. 26, 1940' 1 InJenTar 3141M JUQLJQJI I! g 15-- 2/ 2" Patented July 29, 1941 UNITED IsrAr:

, 7 2,250,637 r r BRAKE HEAD WEAR ELEMENT Malcolm S. Johnson;

' Illinois Railway Equip Chicago, Ill., assignor to ment Company, Chicago,

111., acorporatio'n of Illinois Application February 26,

1940, Seria1No.320,921,

5 Claims. (c1. 188-236) My invention relates to a self-locking'wea'r take-up and wear resisting element adapted to the standard type of brake head and brake shoe for the purpose of firmly anchoring the shoe to the brake head against vibration and wear producing movement between the head and shoe during train operation. o

The invention has for its object the provision of a single piece element adapted'to take up wear previously encountered by thelshoe-lu'g en: gaging lugs of the brake head soas to provide the comparatively snug relation. between the brake head and shoe required by the" A. A. R. rules and thereby enabling continued in service; preventing further wear of the brake head and maintaining the required distance between the upper and lower lugs of the head. v

The invention also vision of an element which may be easily applied to brake heads in use, even though more or less worn, constructed to permit the brake shoe keyto pass therethrough and efiect wedging relation with the key to prevent its accidental movement into shoe unlocking position; the element being constructed to effect locking engagement with the brake head to prevent its loss in the event of removal of the brake shoe; the element at the same time preventing disengagement between the brake head and the hanger. i

The enumerated objects, as well as others, and the advantages of my invention will all be readily comprehended from the detailed description of the accompanying drawing wherein;

Figure 1 is a perspective view of my improved wear element as viewed from its rear.

Figure 2 is a perspective view of the forward shoe receiving face of a brake headiillustrating a worn shoe supporting lug.

Figure 3 is a similar view of the forward face of a brake head with the lower portion broken away and showing my wear element applied to the shoe retaining lugs. t

Figure 4 is a vertical sectional View, somewhat enlarged, of portions of the head lugs with the wear element applied and a portion of the shoe locking key inserted in place.

Figure 5 is a perspective view of one of the supplemental sections shown applied in Figure 3 and employed with excessively worn lugs as disclosed in Figure 2.

My improved wear element is intended for the standard type of brake heads and shoes at present in use on railroads and is so constructed that it can be easily applied, whether the head is new or the brake head to. be

has for its object the e ing strap section worn, without necessitating change or alteration in the head and shoe construction; the wear element normally being constructed to be reversible and to enable application without need for special tools or skill.

The heads and shoes generally consist of more or less rough castings with certain tolerancesin manufacture to enable easy insertion of the shoe lug (not shown) between the vertically spaced lugs 10, H of the brake head 12 and as a result it is never possible under such conditions to obtain a tight fit between'the brake shoe and the brake head; infact the tolerances are such that an undesirable excess play between the brake head and shoe lugs is encountered which permits the shoe to'vibrate in an up and down movement when the strain is in motion. Brake shoes are of hard cast iron while the brake heads are of malleable iron and hence softer material, with the weight of the comparatively heavy shoe being carried by the lower supporting lug of the brake head. With these conditions and the constant movement or vibration of the shoe the head lugsand particularly the lower shoe supporting lugs 11 of the brake heads readily become badly worn on their upper surfaces as shown at 13 in Figure 2; the wear rapidly increasing in proportion to the amount of play between the lugs of the head and the shoe, permitting excess travel of the shoe independently of the head during brake application which" causes the shoe lug to cut into the head lugs and to produce wear at the contactpoints between the rear of the shoe and the forward face of the brake head lugs. The excessive play and wear mentioned greatly reduces the useful period of the brake head and necessitates the undesirable expense and labor of frequent brake head renewal.

My improved one-piece wear element hi; shown in Figure 1, preferably is stamped out of a hard metal plate or sheet steel to provide the two similar lug protecting plate sections "l5, l5 arranged substantially parallel with each other and held in predeterminedspaced relation by the connect? 16 which is integral with the rear edges of the plate sections; the plate sections 1 5, 15 being spaced from each other in keep ing with the spacing between the upper and lower lugs I0 and l I of the brake head so as to snugly fittherebetween, as shown in Figures 3 and 4. y

The plate sections l5, 15 are of lengthcorresponding with the widths of the head lugs it, 1 l, with straight forward edges in keeping .with the forward sides ofthe head lugs and withthe intermediate'portions of the plate sections'ofiset in a vertical direction toward each other as shown at I7; these offset portions front to rear and being of width corresponding to the istance between the usual laterally usual curved sides of the shoe lugs; thus also adapting the Wear element to the depression Worn into the faces of the head lugs by the shoe lugs.

The intermediate off-set portions I1 of both plate sections I5 are provided with slots or openings I9 arranged to register with the locking key receiving passages in the lugs l and II of the brake head as well as with the passage. in the shoe lug; the openings I9 being of size suflicient to permit the shoe locking key; of which a portion is shown at 29 in Figure 4, to pass therethrough.

The opennigs I9 in the plate sections are cut so as to leave the tongues 2| integral with the forward sides of the openings I9 and these tongues 2| are bent in opposite directions toward the outer faces of the plate sections 2| to enter into the key receiving opening in brake head lug l9 and the other tongue 2| to enter the key receiving opening in; the lower brake head lug II; the tongues 2| effecting locking engagement with the .head lugs. With the wear element 4 stamped from sheet steel it possesses suffi cient resiliency to' tongue of the upper plate section arranged flush with the forward side of the key slot in the upper lug III as shown in Figure 4, while the tongue 2| of the bottom plate section initially is arranged at a slight angle to the forward wall of the key slot in head lug H, as shown in dotted lines in Figure 4, so as to effect frictional locking engagement with the shoe locking key 20 when the latter is driven downwardly through the lugs I0 and H of the brake head and through the intervening lug of the brake shoe whose lug (not shown) engages the opposing faces of the two plate sections |5, |5, which maintain the shoe lug out of contact with the head lugs.

The connecting strap section l6, as shown in Figures 3 and 4, will be disposed rearward ofthe shoe lug and extend vertically across the hanger receiving socket 22 in the brake head and consequently will prevent the hanger-link moving out of the socket 22 when occasion requires the shoe to be removed; the wear element l4 maintaining its self-locking engagement with the brake head.

As previously stated, the lower lug I I which support the weight of the brake shoe is subjected to the greatest wear and in the event the lower lug becomes excessively worn requiring a plate section I5 of greater thickness, the lower plate section of my improved wear element may then be provided with two triangular supplemental sections 23, as shown in Figure 5, which match the portions of the plate section 5 on opposite sides of the intermediate off-set portion I1; these triangular sections 23 being-made of sheet steel of the necessary thickness and being preferably welded'to the outer face of the lower plate section in Figure 3.

I5 of the element as show:

defined in the appended claims.

What I claim is: i

1. A reversible brake head wear element comprising a pair of similar plate sections connected cured to the brake 2. A wear element for the vertically spaced lugs in the brake head and to yieldingly hold the plate sections in spaced relation.

3. A wear element for a shoe holding brake head adapted to be disposed between the verti cally spaced apart lugs of a brake head and comprising a pair of spaced apart similar plate sections adapted to bear against the lower and the upper faces of the respective brake head lugs, said plate sections being provided with key-receiving openings and with oppositely disposed key-engaging tongues, and a resilient strap section connected to the rear longitudinal edges of the plate sections intermediate of their ends whereby the plate sections are maintained against the opposing faces of the brake head lugs.

4. A wear element for a. shoe holding brake head adapted to be disposed between the vertically spaced apart lugs of a brake head and comof vertically spaced similar plate sections provided with registering key-receiving resilient tongues at one side of said openings and extendtermediate of their ends being provided with oping in opposite directions and a resilient strap posingly disposed ofiset surfaces adapted to effect section integral with the rear longitudinal edges engagement with the lug of a brake shoe, said of the plate sections intermediate of the ends surfaces being provided with key-receiving slots thereof whereby the plate sections are yieldingly and with vertically extending resilient tongues held in spaced relation. disposed in opposite directions at one side of the 5. A reversible brake head wear element comslots, and a resilient strap section integral with prising a single piece member formed to provide the offset surfaces of the plate sections at the a pair of similar plate sections vertically spaced rear longitudinal edges thereof whereby the plate to seat against the opposing faces of the spaced 10 sections are yieldingly held in spaced relation. apart lugs of a brake head, the plate sections in- MALCOLM S. JOHNSON.

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