US2710750A - Cushioning units - Google Patents

Description

June 14, 1955 E. H. BLATTNER 2,710,750.

CUSHIONING UNITS Filed Aug. 24, 1955 k e 9 x 2 g l2 2 v FIG. 2

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FIG. 4

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Inventor;

Emil H. Blattner By wh his AHor'ney CUSHIONING UNITS Emil H. Blattner, Williamsville, N. Y., assignor to The Symingtou-Gould Corporation, Depew, N. Y., a corporation of Maryland Application August 24, 1953, Serial No. 376,124

3 Claims. (Cl. 267-9) This invention relates to a cushioning device for frictionally dampening the harmonics of supporting springs with which it is used, and has for its primary object the provision of an improved seating arrangement on shoes of a cushioning unit such as shown in Blattner Patent 2,233,396.

In the cushioning unit of the above patent three counterpart shoes are urged into frictional engagement with a housing by three transversely acting coil springs, the latter being spaced axially of the unit. So as to distribute the force of the springs uniformly between the several shoes, each of the springs acts on all of the shoes and is disposed at a different angle to each shoe, with the axis of each spring bisecting one of the shoes and extending between the contiguous edges of the other two shoes.

To overcome the otherwise almost insurmountable problem in assembly, each spring seat on each shoe is formed as part of a. seat group, the group as a Whole being adapted to provide a seat for a spring in any of the three possible angular dispositions.

There is no particular difficulty in providing in each spring seat group a central spring seat of adequate area for seating a centrally acting spring but seating of a side acting spring end which straddles the opening between and acts on a pair of shoes presents a different problem. To bridge the gap and distribute the force of the spring uniformly between the two shoes, a cap is fitted over the side acting end of the spring. However, due to the limited space available, the seats for the capped spring ends in the seat groups of the Blattner patent are restricted to circular segments which furnish bearing only for the sides of the caps. As a result, the spring caps wear excessively and the spring ends ultimately break through and gouge into the shoe, with consequent detriment to the action of the cushioning unit and decrease in its effective life.

it is therefore another object of the invention to provide an improved spring seat group for shoes of the type of cushioning unit above described, wherein by change in the inner configuration of the shoes, the side, as well as the central spring seats, are made of ample bearing area to ensure long effective life of the cushioning unit.

An additional object of the invention is to provide a shoe for a cushioning unit of the type described, having an improved spring scat group, wherein the bearing area of each of the side spring seats is increased without expense to the bearing area of the central seat or the strength of the shoe.

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

Figure l is a vertical sectional view of a cushioning unit embodying the present invention;

Figure 2 is a horizontal sectional view taken along lines .2-2 of Figure 1;

Figure 3 is a front elevational view showing the inner rates Patent Patented June 14, 1955 face of one of the shoes of the cushioning unit of Figure 1;

Figure 4 is a transverse sectional view taken along lines -l-4 of Figure 3;

Figure 5 is a transverse sectional view taken along lines 5 of Figure 3; and

Figure 6 is a transverse sectional view taken along lines 6-6 of Figure 3.

Referring now in detail to the drawings, in which like reference characters designate like parts, the cushioning unit for which friction shoes having the improved seating arrangement of the present invention, are particularly designed, is comprised of a housing 1 formed of a cylindrical barrel or sleeve 2 and an end plate 3, the latter projecting radially beyond the barrel to provide an overhanging annular flange 3a. Telescopingly associated with the housing 1 and adapted to project into and frictionally engage the inner cylindrical surface 4 of the sleeve, are a plurality of counterpart friction shoes 5, preferably three in number, the shoes having cylindrically convex outer surfaces 6 conforming to the inner surface 4 or" the sleeve 2. Each of the shoes terminates at its lower end, outwardly of the housing, in a radially projecting flange 7, the latter forming a support or bearing for an annular collar or ring 8, which, through the flanges 7, interlocks and moves with the shoes.

The housing and the telescopingly related shoes are normally urged outwardly axially of each other to maintain their engagement with supporting and supported members (not shown), with which the cushioning unit is associated, by a coil spring 9, encircling the housing 1 and interposed between the confronting flange 3a of the end plate 3 and the collar 8.

Designed for use with supporting spring means with which it is associated, such as a bolster supporting spring group (not shown) of a railway truck, in which it replaces one of the springs, the cushioning unit cushions or dampens the periodic oscillations of the spring means by friction engendered between the shoes 5 and the housing 1. This friction is obtained by a plurality of transversely acting springs 10, usually three or more, the springs being spaced longitudinally or axially of the unit and, for uniform distribution of force, each engaging all of the shoes but at a difierent angle. For the disclosed three shoes and springs, the preferred arrangement is with the axes of adjacent springs displaced, longitudinally of the unit, substantially 60, and the axis of each spring bisecting one of the shoes and projecting between the other two shoes. As mentioned, the problems, particularly in assembly, make it almost imperative that each shoe, at each of its spring seat locations, be adapted to. seat a spring disposed at any of the three angular dispositions. it is to an improvement in the spring seat groups 11 at these several locations, whereby each group is enabled selectively to seat any of the springs and provide maximum seating surface, that the present invention is particularly directed and that will now be described.

As in the cushioning unit of Blattner Patent 2,233,396, the contiguous lateral edges 12. of the shoes 5, which laterally delimit their cylindrical surfaces 6, lie in a plane extending substantially radially of the unit, and the inner face or surface 13 of each shoe is a plane surface substantially normal to the radial plane bisecting the shoe. So, also, each spring seat group it has for the centrally reacting spring end a central circular seat 14 which, for centering the spring, is recessed in the inner face 13 of the shoe and is disposed substantially parallel thereto. For the side reacting spring ends, preferably capped, as in the Blattner patent, by spring caps 15, there are provided in each seat group a pair or" laterally spaced seats 16, in part formed by segmental circular surfaces 17 inset in the inner face 13 of the shoe below the level of the circular seat 14. The segmental surfaces 17 are angularly and for the illustrated three shoe arrangement, preferably obliquely disposed to each other and to the central seat 14 and serve as the base portion of one of a pair of cylindrical segments 18 which interrupt and intersect centrally of the central seat 14 and serve to center the side reacting spring end.

The other part of each of the side or laterally spaced seats 16 is formed on the shoe outwardly or on the opposite side of the plane of the central seat 14 from the segmental surfaces 17 by shouldering the shoe to provide plane surfaces 19 adjacent either edge, each coplanar with and included with the circumference of one of the segmental surfaces 17. For convenience in manufacture, as well as to add strength to the shoe, the requisite shouldering preferably is provided by a pair of laterally spaced angularly disposed walls 20 confining the inner face 13 of the shoe and extending longitudinally of the shoe to include the several spring seat groups. These confining walls preferably are planar, with each wall coplanar with one of the segmental surfaces 17 of each seat group, and may extend to and intersect the lateral edges 12 of the shoe, the walls for the disclosed three shoe and spring arrangement, each being substantially normal to the intersected of the lateral edges.

As shown, the portions 19 of each of the confining walls 20, which are included within the circumference of the associated of the segmental surfaces 17, while forming extensions of such surfaces, are not contiguous therewith, due to interruption of each wall by an edge of a projected cylinder of which the central spring seat 14 forms the base. With the wall portions 19 added to the segmental surfaces 17, the bearing area for the spring caps 15 of each of the side seats 16 is substantially double that of the Blattner patent and equal to that of the central seats 14. As a consequence, the wear on the spring caps is drastically reduced and the effective life of the cushioning unit correspondingly increased.

With each spring seat group 11 formed in the manner above described, the longitudinal spacing between the several seat groups of each shoe will depend upon the longitudinal dimension of the shoe and the extent of telescoping of the shoe within the housing 1, as determined by the travel for which the cushioning unit is designed. In any case, it is preferred that the several spring groups be so spaced as to concentrate the transverse forces of the springs over that portion of the shoes which frictionally engages the housing during the travel of the cushioning unit. When the travel is relatively short, as in the illustrated cushioning unit of one and eleven-sixteenths inches 1 1 standard travel, the limited longitudinal dimension of the shoes necessitates close spacing of the spring seat groups, consistent with non-interference between the springs. To simplify manufacture in such case, the surfaces of the central seats 14 may extend and merge between the seat groups.

From the above detailed description it will be apparent that there has been provided in a shoe of a cushioning unit of the type described an improved spring seating arrangement wherein, within the limited space available, the seating surfaces for the side acting spring ends have been substantially doubled over those obtainable in the prior art, with consequent increase in the effective life of the cushioning unit, and in the strength of the shoe, and Without complication in manufacture. 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. In a cushioning unit having a sleeve, a plurality of friction shoes extending into said sleeve and transversely acting coil springs each acting against all of said shoes and at a different angle for urging said shoes into frictional contact with said sleeve, the improvement in shoe construction comprising a plurality of spring seat groups formed in and spaced longitudinally of each shoe and each adapted to selectively seat one of said springs at any of said angles, each of said seat groups including a circular surface inset in an inner face of a shoe, a cylindrical segment including a base portion interrupting said circular surface and extending therebelow into said shoe, said base portion being in a plane oblique to said surface, and a surface adjacent an edge of said shoe and above said circular surface, said adjacent surface being coplanar with and extending Within the circumference of said base portion.

2. In a cushioning unit having a plurality of counterpart friction shoes frictionally engaging a housing and urged thereagainst by a plurality of transversely acting springs, an improved shoe having a cylindrically curved outer wall, a flat inner wall disposed substantially normal to a radius of said outer wall, a pair of spaced walls laterally confining said inner wall, said confining walls being flat and angularly disposed to each other and to said inner wall, and a spring seat group for selectively seating one of said springs at any of a plurality of angles, said seat group including a circular surface inset in said inner wall and defined laterally by cylindrical surfaces coradial therewith and each interrupting one of said confining walls, and a pair of cylindrical segments each interrupting said inner wall adjacent a side thereof, each of said segments having a segmental circular base portion coplanar with and including with its circumference part of the adjacent of said confining walls.

3. In a friction shoe for a cushioning unit, the shoe being of the type having a spring seat group for selectively seating a transversely acting coil spring at any of a plurality of angles and formed of a central circular spring seat and a segmental circular surface extending into said shoe beyond and disposed at an angle to said central seat, the improvement comprising a surface on said shoe on the opposite side of the plane of said central seat from said segmental surface, said last-named surface being coplanar with and extending within the circumference of said segmental surface to form therewith a spring seat.

References Cited in the file of this patent UNITED STATES PATENTS

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