US2847129A

US2847129A - Draft mechanism

Info

Publication number: US2847129A
Application number: US395649A
Authority: US
Inventors: Emil H Blattner
Original assignee: Symington Gould Co
Current assignee: Symington Gould Co
Priority date: 1953-12-02
Filing date: 1953-12-02
Publication date: 1958-08-12
Anticipated expiration: 1975-08-12

Description

Aug. 12, 1958 E. H. BLATTNER DRAFT MECHANISM Filed Dec. 2, 1953 FIG. 1

FIG. 2

Inventor:

3 6 Emil H. Blattner FIG. 3

his Attorney nited DRAFT MECHANISM Application December '2, 1953, Serial No. 395,649 8 Claims. (Cl. 213-65) This invention relates to draft mechanism and has for its primary object the provision of improved draft mechanism of exceptional capacity.

Another object of the invention is to provide improved draft mechanism wherein the yoke for connecting the draft gear to an associated coupler is formed as an integral part of the housing of the draft gear, whereby the space normally occupied by the yoke in a draft gear pocket is saved and utilized for increasing the lateral dimensions and, correspondingly, the capacity of the draft gear.

An additional object of the invention is to provide improved draft mechanism wherein, by combining housing and yoke in a single structure, a plurality of pairs of friction shoes and their associated spring means are enabled to be housed in the housing and act thereagainst for effectively cushioning excessive impacts.

A further object of the invention is to provide improved draft mechanism of high-capacity for use with a proposed A. A. R. Type F coupler, wherein a front follower, containtable within a yoke formed integrally with the housing of the draft gear, is of such arrangement and construction as to be effectively centered under buifing forces.

Other objects and advantages of the invention will appear hereinafter in the detailed description, be particu larly pointed out in the appended claims, and be illustrated in the accompanying drawings, in which:

Figure 1 is a side elevational view, with portions broken away and shown in vertical section, of a preferred embodiment of the draft mechanism of the present invention.

Figure 2 is a plan view, with portions broken away and shown in horizontal section, of the draft mechanisms of Figure 1, the coupler and connecting pin having been removed.

Figure 3 is a vertical sectional view taken along the lines 3-3 of Figure 2; and

Figure 4 is a vertical sectional view taken along the lines 44 of Figure 1, with the coupler removed.

Referring now in detail to the drawings, in which like reference characters designate like parts, the improved draft mechanism of the present invention is designed particularly to fit within an A. A. R. standard draft gear pocket and to have a capacity in excess of 30,000 ft. lbs., far above the present A. A. R. standard of 18,000 ft. lbs. Although the standard dimensions for such a draft pocket are 12%" x 12 /2" x 24 /8", the dimensions for the draft gear, itself, when a separate yoke is used, are reduced to 9 x 12 /2" x 24%, the difference in the lateral dimensions affording space within the associated center sills for the accommodation of the yoke conventionally employed for transmitting draft forces to the draft gear. As will become evident as the description proceeds, the conventional separate yoke is here dispensed with and the yoke, instead, is combined or made integral with the housing of the draft gear, thus saving for the draft gear the space normally alotted to the yoke and Patent 0 Patented Aug. 12, 1958 enabling the housing to be increased in lateral dimensions to substantially the full size of the standard pocket, 12 /2 x 12 /2", this increase in volume being put to effective use to correspondingly increase the capacity of the draft gear.

In its illustrated form, the draft mechanism of the present invention is comprised, as mentioned, of a combined or integral yoke and housing unit, designated as 1, which is especially designed to supplant a separate vertical yoke, and the draft mechanism will be so described. It will be understood, however, that the draft mechanism may as well be used to replace a horizontal yoke, in which case, the draft mechanism, as here described, would be turned on its side.

Serving both to house the cushioning elements of the draft gear and as the rear portion of the yoke by which draft forces are transmitted to these elements, the housing or housing portion 2 of the combined unit 1 is formed longitudinally of top and bottom walls 3, and connecting side walls 4, the several longitudinal walls being connected at their rear ends by an integral end wall 5 closing the rear or inner end of the housing. The side walls 4 of the unit end somewhat forward of its longitudinal midpoint. However, the top and bottom walls 3 extend the full length of the unit and assume, forwardly of the side walls, the configuration of the forward portion of a conventional yoke, the particular configuration varying with the type of coupler with which the draft mechanism is to be used. The forward extension of the top and bottom walls 3 thus provides a pair of vertically spaced arms 6 integral and merging at their rear ends with, but narrower than, their respective top and bottom walls. When applied, as in the illustrated embodiment, to a proposed A. A. R. Type F coupler, only the butt or rear portion 7 of the shank of which is shown, the arms 6 are connected adjacent their forward extremities by a pair of transversely spaced upstanding or upright webs 8 which, with the arms, define a hooded opening 9 for the reception of the coupler. The coupler is connected to the combined unit 1 in the same manner as to a conventional yoke, by a vertical pivot pin 10 which rides at either end in longitudinally elongated slots 11 in the arms 6.

Rearwardly of the arms 6 the housing 2 is substantially square in cross-section and provides, interiorly of its several walls, an inner pocket, cavity or recess 12, bounded or confined at the rear end by the rear or end Wall 5 and at all sides or laterally by the longitudinal Walls 3 and 4". The pocket 12 extends the full interior height of the housing between the top .and bottom walls 3 and opens, forwardly, into the, in turn, forwardly opening bell-mouth 13 of the housing. Defining the mouth 13 vertically are a pair of transversely or laterally, vertically directed, oppositely inclined or sloping friction or wedging surfaces 14, which diverge or flare outwardly of the housing and each of which extends substantially the full interior height and forms the forward portion of the inner face of one of the side walls 4. Each of these friction surfaces 14 is preferably flat and terminates inwardlyof the housing in an instanding or inwardly directed shoulder or abutment 15, the two abutments being aligned transversely of the housing.

Cooperating with the friction surfaces 14 and serving as the friction or wedge elements of the draft gear, are a plurality of counterpart wedges or friction shoes 16, each having, intermediate-its longitudinal ends, a wedging or friction face 17 corresponding in configuration to and confronting and adapted to frictionally engage one of the friction surfaces 14. The wedges 16 are arranged in sets, two of which preferably are provided, each set comprising a pair of laterally or transversely spaced wedges, one facing each of the friction surfaces 14. The

shoes of each set are urged into engagement with the friction surfaces on the housing by laterally or transversely acting spring means, preferably in the form of a pair of opposed sets of semi-elliptic leaf springs 18. As mentioned, two sets of wedges and their associated leaf springs are preferred, both for ready production and assembly and to avoid the possibility of sticking in action, as might well occur with a single pair of wedges, each having a friction face of the extended area necessary to encompass one of the friction surfaces 14. The preferred pair of sets of wedges are arranged side by side in superposed relation, with two wedges, one of each set, in engagement with and substantially covering or encompassing each of the friction surfaces 14.

The wedges 16 initially or normally project or extend forwardly beyond the mouth 13 of the housing and are held in that position by a lug or abutment 19 outstanding from each of the wedges rearwardly of its friction face 17 and overlapping and adapted to interlock with the shoulder at the rear of the cooperating of the friction surfaces 14. For guiding the wedges in their movement longitudinally of the housing, each' of the lugs 19 is slotted centrally to slidably receive a portion of one of a plurality of ribs 20, each formed integrally with and instanding horizontally from one of the side walls 4. For the disclosed two sets of wedges, a pair of the ribs 20 are provided on each of the side walls, the ribs of each pair being vertically spaced and the corresponding ribs of the two pairs being coplanar.

Rearwardly or inwardly of their lugs 19 the several wedges 16 end in transversely or laterally directed, preferably planar, end faces 21 which are adapted to abut and wipe against or frictionally engage the front face 22 of a floating follower or follower block 23 common to the several wedges, the floating follower being movable longitudinally of the rear pocket 12 in the housing. For

cushioning the rearward or inward movement of the float-- ing follower 23, and providing the restoring force by which the wedges 16 are returned or restored to normal position when relieved of a compressive force, there are seated in the pocket 12, rearwardly of the floating follower, resilient or release spring means, preferably in the form of sets of double coil springs 24 for maximum capacity, one such spring being provided for and aligned in tandem with each of the sets of wedges 16. Like the sets of wedges, the double coil springs 24 are arranged in parallel, longitudinally of the housing 2, and in superposed relation, with each spring bearing atits rear end against the rear wall 5 and at its front end against the rear face 25 of the floating follower 23.

For centering the springs the floating follower 23 preferably has at either side a double-bowed rearwardly directed flange 26, the flanges together being of substantially figure eight (8) shape and affording vertically spaced spring seats 27, one for each of the double springs 24. While not normally necessary, either similar spring seats or other suitable centering means, if desired, may be provided on the rear wall 5 to center the rear ends of the springs. Although not centering the rear ends of the springs 24 vertically, the disclosed structure does serve to center them laterally through the lips 28 instanding from the rearward extensions of the wedge-guiding ribs 20, the ribs thus preferably extending from the shoulders 15 to the rear wall 5 and therebetween, serving as lateral guides for the floating follower 23 as it moves longitudinally of the housing.

For transmitting bufling and draft forces to the wedges 19 and their associated coil and leaf spring elements, there is provided a front follower 29 which is straddled by and included vertically between the arms 6 and has a rear face 30 in wiping or rubbing engagement with transversely directed, preferably planar, front faces 31 of the wedges.

Bufling forces are transmitted directly to the front follower 29 from the coupler, the butt 7 of the latter, when a type F coupler, for this purpose seating in a forwardly directed spherically concave seat or recess 32, formed centrally in the front follower. Under such forces the front follower in its rearward movement may tend to angle relative to the arms 6. To prevent such angling, the front follower preferably is provided on either side of the recess 32 with a pair of vertically spaced, forwardly projecting legs 33 which are confined, laterally and vertically, within the arms 6 and have at their forward ends cylindrical sockets 34 engageable with the pivot pin 10 above and beyond the coupler butt 7. Thus interlocked in buff, both with the coupler through its concave recess 32 and with the pivot pin through the cylindrical sockets 34 on its legs 33, the front follower is effectively centered and prevented from gouging into the arms 6. In draft, such centering is unnecessary since, then, the front follower is held between the wedges 16 and front draft or stop lugs (not shown) fixed to the center sills (not shown) Within which the draft gear is seated.

Whether in buff or in draft, the action of the front follower on the wedges 16 and their associated elements is the same, in both cases forcing the wedges inwardly, both longitudinally and laterally of the housing, and in process creating friction not only between the friction surfaces 14 on the housing and friction faces 17 on the wedges, but also between the front and

rear faces

31 and 21 of the wedges and the confronting faces of the front and floating

followers

29 and 23. During this compressive movement, the friction faces and surfaces of the wedges and housing are maintained in contact by the leaf springs 18, the latter also adding to the capacity of the draft gear by resisting the lateral contraction or compression of the wedges and the coil springs 24 aiding by resisting the longitudinal inward movement of the wedges. On release of the compressive force, the coil springs 24, as previously mentioned, force the wedges forwardly and restore them to their normal interlocked position with the housing. In order that the wedges, when in normal position will remain so, and thus maintain the several components of the draft gear in assembled relation, both the leaf springs 18 and the coil springs 24 are preferably placed under initial compression when the draft mechanism is assembled.

From the above detailed description it will be apparent that there has been provided improved draft mechanism having a combined housing and yoke and, by utilizing in the housing the space normally allotted to a separate yoke, having a capacity almost double that of the conventional friction draft gear. It should be understood that the described and disclosed embodiment is merely exemplary of the invention and that all modifications are intended to be included which do not depart either from the spirit of the invention or the scope of the appended claims.

Having described my invention, I claim:

1. Draft mechanism comprising a housing having a forwardly opening pocket closed at all sides and rear by longitudinal and rear walls of said housing, spaced yoke arms each integral with and projecting forwardly of each one of a transversely spaced pair of said longitudinal walls for connecting said housing to an associated coupler, outwardly diverging friction surfaces in said housing and extending between said longitudinal walls, a plurality of wedges in said housing and each having a wedging face frictionally engaging one of said friction surfaces, spring means between and acting laterally on certain of said wedges for maintaining said frictional engagement between said wedges and housing, a front follower straddled by said arms and interposed between said wedges and coupler and frictionally engaged by said wedges, release spring means within said pocket inwardly of said wedges and normally urging said wedges outwardly of said housing, a floating follower common to and between said wedges and spring means and frictionally engaged by said wedges, and means on said wedges and housing and interlocked in normal position under force of said spring means for maintaining said draft mechanism in assembled relation.

2. Draft mechanism comprising a housing having a forwardly opening pocket closed at all sides and rear by longitudinal and rear walls of said housing a pair of spaced yoke arms each integral with and extending forwardly of and substantially coplanar with one of a transversely spaced pair of said longitudinal walls for connecting said housing to an associated coupler, outwardly flaring friction surfaces in said housing and extending between said longitudinal walls, a plurality of sets of wedges arranged side by side in said housing and each including a pair of opposed wedges, one frictionally engaging each of said friction surfaces, spring means between and acting laterally on the opposed wedges of each set for urging said wedges into said frictional engagement with said housing, a plurality of release spring means within said pocket and each aligned with one of said sets of wedges, a floating follower between and common to said wedges and release spring means for transmitting forces therebetween and means on said wedges and housing for limiting relative forward movement of said wedges and maintaining said draft mechanism in assembled relation.

3. Draft mechanism comprising a housing substantially square in cross-section, a pair of spaced yoke arms each integral with and projecting forwardly of each one of a pair of spaced walls of said housing for connecting said housing to an associated coupler, outwardly flaring wedging surfaces in said housing and extending between said spaced walls, a plurality of sets of wedges arranged side by side in said housing, each of said sets including a pair of opposed wedges, one frictionally engaging each of said wedging surfaces, means instanding from said housing and slidably received in slots in said wedges for guiding said wedges during longitudinal movement thereof relative to said housing, and means within said housing and acting on and normally urging said wedges outwardly thereof.

4. Draft mechanism comprising a housing, friction means in said housing for cushioning longitudinal forces applied thereto, spaced yoke arms integral with and projecting longitudinally beyond said housing and pivotally connectable by pin means to an associated coupler, and a front follower interposed between said friction means and said coupler for transmitting bufling forces therebetween, said front follower being straddled by said yoke arms and having a pair of spaced forwardly extending legs engageable with said pin means on either side of said coupler for centering said follower during rearward movement thereof relative to said housing in response to buffing forces.

5. Draft mechanism comprising a housing fittable in a standard draft gear pocket between center sills and substantailly equal in cross-sectional area to the area included between said center sills, said housing having longitudinal walls and a rear wall confining at all sides and rearwardly a forwardly opening pocket therein, a pair of spaced arms projecting forwardly of said housing and each integral with one of a spaced pair of said longitudinal walls, spaced outwardly diverging wedging surfaces instanding from opposite of said longitudinal walls and each extending substantially the full width thereof, opposed wedges in said housing and having wedging faces frictionally engaging and substantially covering said wedging surfaces, spring means between and acting laterally on said opposed wedges for maintaining said frictional engagement between said wedges and housing, spring means within said pocket inwardly of said wedges, a floating follower within said pocket between said wedges and last named spring means, and means on said wedges and housing and interlocked in normal position under force of said spring means for maintaining said draft mechanism in assembled relation.

6. In draft mechanism a draft gear comprising a housing, spaced outwardly divergent wedging surfaces within said housing and extending substantially the full distance between spaced longitudinal walls thereof, a plurality of sets of wedges arranged side by side in said housing and each including a pair of opposed wedges each having a wedging face frictionally engaging one of said wedging surfaces, spring means acting on said wedges for normally maintaining said frictional en gagement between said wedges and housing, lug means on and outstanding from each of said wedges and each engageable with abutment means on said housing for limiting outward movement of said wedges relative thereto, and rib means in and extending longitudinally of said housing and each instanding form a wedging surface-carrying wall, each of said lug means being slotted for slidably receiving one of said rib means and guiding said wedges in longitudinal movement thereof relative to said housing.

7. Draft mechanism comprising a housing, a forwardly opening pocket in said housing and confined at all sides and rearwardly by longitudinal and rear walls of said housing, a pair of laterally spaced yoke arms integral with and extending forwardly of a laterally spaced pair of said longitudinal walls for connecting said housing to an associated coupler, yieldable means in said housing within said pocket, means in and extending forwardly of said housing between said arms for transmitting force from said coupler to said yieldable means, and means carried by said housing for limiting forward movement of said force transmitting means relative thereto and maintaining said draft mechanism in assembled relation.

8. Draft mechanism comprising a housing, resilient means within and confined on all sides and rearwardly by longitudinal and rear walls of said housing, a pair of laterally spaced yoke arms integral with and extending forwardly of a spaced pair of said longitudinal walls for connecting said housing to an associated coupler, and means in and projecting forwardly of said housing between said arms and normally limited in forward movement relative to said housing for transmitting force from said coupler to said resilient means and maintaining said draft mechanism in assembled relation.

References Cited in the file of this patent UNITED STATES PATENTS 1,258,935 OConnor Mar. 12, 1918 1,280,282 Newell Oct. 1, 1918 1,323,787 Richards et a1. Dec. 2, 1919 1,470,287 Priebe Oct. 9, 1923 1,488,159 Kadel Mar. 25, 1924 1,956,563 Couch May 1, 1934 2,023,000 Barrows Dec. 3, 1935 2,141,680 Barrows Dec. 27, 1938-