US2141522A - Cushioning device for railroad cars - Google Patents

Description

-'Dec.'27,1 938." Y QQDURYEA. 2,141,522

OUSHICNING DEVICE FOR RAILROAD CARS Filed June 8 1937.

Patented Dec. 27, 1938 UNITED STATES PATENT OFFICE I 2,141,522 CUSHIONING DEVICE FOR GABS Otho 0. Dune, Wate b ry, Conn. Application June 8, 1937, Serial No. 147,18!

Claims. (01. 207-9) cluding friction mechanism and at least one spring for use in railroad cars and which device, 10 upon the imposition of a load, yieldingly resists the same and absorbs the initial shock thereof and upon release of load, operates directly to return the parts to normal position. I

Another object of the present invention is to provide a cushioning device of this kind including a friction mechanism and a main cushioning spring that is directly engaged with. the end members of the devices and is operative upon release of load to return them to normal position without going through the friction mechanism.

A further object of the invention is to provide a cushioning device of this kind which com pensates for manufacturing tolerances and consists of but a relatively few parts requiring little,

if any, machine work and may be readily assembled so as to be produced at a relatively low cost. 7 The above-mentioned objects of the invention, as well as others, together with the several advantages thereof, will more fully appear as the specification proceeds.

In the drawing:- Fig. 1 is a longitudinal sectional view through a cushioning device for railroad cars embodying the preferred form of invention, with the parts in their normal position as when not under load. Fig. 2 is a view similar to Fig. 1 with the parts in their load bearing position. Fig. 3 is a. transverse section through the device of Fig. 1 as taken on the line 33 of Fi 1.

Fig, 4 is a perspective view of one of the parts of the cushioning device. I Fig. 5 is a perspective view of a certain friction shoe or block embodied in the device and which shoe or block will 'be more fully-referred to later. The cushioning devices with which the present invention is more particularly concerned are those including friction mechanismand at least one spring for yieldingly resisting and gradually absorbing shocks and which devices may be used for draft gearand buffer purposes as well as for snubbing the action of truck springs.

For ease of illustration, the invention is herein illustrated as embodied in a device for snubbing the action of the truck springs of a railroad car. This is to be considered only by way of illustration and not by way of limitation.

Referring now in detail to that embodiment of the invention illustrated in the drawing l0 5 and ii indicate respectively the top and bottom load bearingmembers of a cushioning device in the form of a truck spring snubber adapted for insertion between a truck bolster end and the lower arch of a truck frame, not shown. As-10 4, includes a radial flange-like end i2 and an .arcuate substantially semicylindrical body por- 15 tion i3. Said load bearing members are arranged with the body portion of 'onemember facing endwise toward the flange of the other member, the body portions of both members being arranged in longitudinal overlapping relation and 20 enclosing suitable friction mechanism as will later appear. In the end I! of each member I 0 and ii isan axial opening 12a whereby assembiingof the parts of the'cushioning device may be facilitated as will later appear. 25

Each body portion i3 is provided between its ends with an internal, taperingfriction surface it, defined at its ends by semicylindrical inner and outer end shoulders i5 and i6. respectively. Each internal tapering friction surface 86 is so curved transversely, the ends of said surfaces being of the same radius but struck from different centers which are off-center with respect to the'center of curvature for the outer surface of the body and which outer surfaceis concentric 35 with the flange i2.

Between the overlapping parts of the body Por tions i3-i8 is provided a pair of coacting friction blocks or shoes ii-ii, of the same shape or form and one of which appears in perspective 40 in Fig. 5. Each shoe has a longitudinal outer surface I8 that, fits against the taper of an associated surface is, a transverse end surface. i9 and a diagonal friction surface 20. In each shoe is a longitudinal opening 2i and on the end sur- 45 face I9 thereof, is an arcuate flange-like extension 22. This extension not only increases the area of the surface it, but forms a shoulder for coacting with the shoulder it of the associated member iii-ii to form a solid stop. The shoes v5 are arranged in opposed relation with the diagonal or angular friction surfaces 20-20 engaged with each other. A retainer bolt 23 of a diameter somewhat less than that of the openings 2!, extends through the openingsti in both 55 The main compression resistance and release spring 21 is of helical formation and surrounds the body portions l3 of both the members I!) and II and has direct engagement at its ends with the flanges l2 of said members. This spring has an internal diameter providing a relatively snug fit upon the outer surfaces of said overlapping body portions l3 of both members I and H and has an external diameter approximating that of the said flanges l2. Preferably the spring 21 is made from octagonal bar stock.

In the assembly of the device the nut 25 is screwed down tight to bring the various convolutions of the spring 26 into engagement to make the spring solid, after which the nut is backed off for about two turns. This will open up the convolutions of the spring, to an amount which provides for the necessary relative movement between the friction blocks or shoes. Thus the spring is employed to establish an initial pressure for said blocks or shoes and maintains them in initial pressure condition, the end of the bolt associated with the nut 25 being upset to prevent unscrewing of the nut.

In Fig. 1, the parts are shown in their normal non-load bearing position. When a load is imposed upon one or the other of the flanges l2-|2 of the members In and II, in the relative movement of said members toward each other, the spring 21 is placed under compression and at the same time the friction grip is increased not only between the blocks I'III and the bodies of the members If) and II. but also between the blocks and II, respectively, with the flat inner surfaces of the convolutions of the spring 21 aids in increasing this grip. This snubs the shock of compression under load. In this action, the blocks vl'l move relatively axially and laterally, the enlarged openings in the blocks permitting the lateral movement and-the spring 26 compressing to permit the axial movement.

So soon as the load which has compressed the device has been removed, the spring expands to immediately return the members to their normal position and this release occurs without the releasing action going through the friction elements. In this way the return of the members [0 and II to normal position is not accomplished through the friction element but only through the spring 21. When said members have thus returned to normal position, the spring 26, which has been placed under compressions by the relative movement of the blocks l1--l'|, re-expands to return the blocks tonormal position wherein their relatively pointed ends engage against the stop shoulders l5. This determines the relatively normal position of the members I0 and when not under a load.

Fig. 2 shows the position of the parts under a load or pressure tendency to move one of the members lO- -ll toward the other, but such a load is shown as less than the capacity of the .it more nearly approaches uniformity of frictional resistance throughout and the tendency to bind and remain compressed under the load imparted thereto is avoided. Therefore, upon release of load, the parts instantly return to normal position and this return is afforded directly through the spring and not through the friction mechanism. By the pressure of the parts more directly associated with the friction blocks or shoes I 1-41, it is possible to establish and to maintain said blocks or shoes in initial pressure condition.

While in decribing the invention, I have referred in detail to the form and arrangement of the parts of the device, the same is to be considered only in the illustrative sense so that I do not wish to be limited thereto except as may be specifically set forth in the appended claims.

I claim as my invention:

1. In a cushioning device for railway cars, the combination of means providing two members that'are relatively movable in an axial direction toward and away from each other, means operatively secured to each member and disposed in overlapping relation and cooperating to form opposed tapered internal friction surfaces, means providing shoes having frictional engagement with each other and with said opposed surfaces, a spring cooperating with said shoes in offering a resistance to the movement of one of said members from its normal position toward the other of said members under the action of 2 load imposed upon one of said members, said spring upon release of load operating directly upon the moved member to return the same to its normal Position.

2. In a cushioning device for railway cars, the combination of means providing two members that are relatively movable in an axial direction toward and away from each other, means operatively secured to each member and disposed in overlapping relation and cooperating to form opposed tapered internal friction surfaces, means providing shoes having frictional engagement with each other and with said opposed surfaces, a spring having direct end engagement wtih said members and cooperating with said shoes in offering a resistance to the movement of one of said members from its normal position toward the other of said members under the action of a load imposed upon one of said'members, said spring upon release of load operating directly upon the moved member to return the same to its normal position.

3. In a cushioning device for railway cars, the combination of means providing two members that are relatively movable in an axial direction toward and away from each other, means operatively secured-to each member and disposed in overlapping relation and cooperating to form opposed tapered internal friction surfaces, means providing shoes having frictional engagement with each other and with said opposed surfaces, a spring surrounding both of said means secured 4. In a cushioning device for railway cars, the

combination of means providing two members that are relatively movable in an axial direction toward or away from each other, means operatively secured to each member and disposed in overlapping relation and cooperating to form opposed tapered internal friction surfaces, means providing shoes having frictional engagement with said opposed surfaces and having frictional surfaces engaged with each other, spring pressed means associated with said shoes for holding said shoes so as to keep said frictional surfaces tightly engaged with each other and for holding said shoes in operative engagement with said tapered friction surfaces of said members, a spring operating at 'its ends against each. one of said members and cooperating with said shoes in offering a resistance to the movement of one of said members from its normal position toward the other of said members under the action of a load imposed upon one of said members, said spring upon the release of load operating directly upon the moved member to return the same to its normal position.

5, In a cushioning device for railway cars, the combination of means providing two members that are relatively movable in an axial direction .tapered friction surfaces of said members, said means on said members and said shoes being formed to provide cooperable shoulders to limit the movement of said shoes with respect to said tapered friction surfaces, a spring operating at its ends against each one of said members and cooperating with saidshoes in offering resistance to the movement of one of said members from its normal position toward the other of said members under the action of a load imposed upon one of said members, and which resistance increases as the movement increases, said spring upon release of load operating directly upon the moved member to return the same to its normal position.

6. In a cushioning device for railway cars, the combination of means providing two members that are relatively movable in an axial direction toward or away from each other, means operatively secured to each member and disposed in overlapping relation and cooperating to form opposed tapered' internal friction surfaces, means providing shoes having frictional engagement with said opposed surfaces and having frictional surfaces engaged with each other, spring pressed means associated with said shoes for holding said shoes so as to keep their frictional surfaces tight- 1y engaged with each other and for holding said shoes in operative engagement with said tapered friction surfaces of said members, a spring operating at its ends against each one of said members and cooperating with said shoes in offering a resistance to the movement of one of said members from its normal position toward the other of said members under the action of a load imposed upon one of said members, said spring upon therelease of load operating directly upon the moved member to return the same to its normal position, said spring surrounding said means on said members and the shoes associated therewith.

7. In a cushioning device for railway cars, the

combination of means providing two membersthat are relatively movable in an axial direction toward or away from each other, means operatively secured to each member and disposed in overlapping relation and cooperating to form opposed tapered internal friction surfaces, means providing shoes having frictional engagement with said opposed surfaces and having frictional surfaces engaged with each other, spring pressed means associated with said shoes for holding said shoes so as to keep their frictional surfaces tight- 1y engaged with each other and for holding said shoes in operative engagement with said tapered friction surfaces of said members, a second spring having its ends engaged against each of said members and cooperating with said shoes in offering a resistance to the movement of one of said members from its normal position toward the .other of said members under the action of a load imposed upon one of said members, said spring upon release of load operating directly upon the moved member to return the same to its normal position.

8. In a cush onin device for railway cars. the combinat on of means providing two similar members that are relatively movable toward and away from each other and each member including a substantially semi-cylindrical body portion having a tapered internal friction surface. said members being arranged with sa d body portions in end to end overlapping relat on so that said su faces are opposed to each other. means providing a friction mechanism Within said overlapped body portions and engaged with the tapered friction surfaces thereof, and a spring surround ng said body portions and arranged at ts ends to exert an outward pressure a ainst each member and cooperating with sa d friction mechanism in offering resistance to the relative movement of said members toward each other.

9. In a cushioning device for railway cars, the combination of means provid n two s m lar members that are relatively movable towa d and away from each other and each member includin? a substantia y sem -cylindrical b dy p rtion havin a tanered internal friction surface. sa d members being arranged with sa d bodv portions in end to end overla ping relat on s that said surfaces are opposed to each other, means providing a f iction mechanism within said overlapped body portions and engaged with the tapered friction surfaces thereof, means providing a shoulder at each end of the friction surface of each body portion, to provide stops which limit the movement of said friction mechanism relative to said body portions, and a. spring surround ng said body portionsand arranged at its ends to exert an outward pressure against each member and cooperating with said friction mechanism in offering resistance to the relative movement of said members toward each other.

10. In a cushioning device for railway cars, the combination of .means providing two similar members that are relatively movable toward and away from each other and each member including a body portion having'a tapered internal friction surface, said members being arranged with said body portions in end to end overlapping relation so that said smfaces are opposed to each other, a pair of friction shoes between said overlapping ends of said body portions, each having a surface for engagement with the internal friction surface of an associated body portion,

, said shoes having engaged friction surfaces arranged obliquely to the axes of said two members, means for providing and for holding said shoes under initial compression, and a spring surrounding said body portions and arranged at its ends to exert an outward pressure against each member and cooperating with said pair of friction shoes in offering resistance to the relative movement of said members toward each other.

11. In a cushioning device for railway cars, the combination of means providing two similar members that are relatively movable toward and away from each other and each member including a body portion having a tapered internal friction surface, said members being arranged with said body portions in end to end overlapping relation so that said surfaces are opposed toeach other, a pair of friction shoes between said overlapping ends ofsaid body portions, each having a surface for engagement with the internal friction surface of an associated body portion, said shoes having engaged friction surfaces arranged obliquely to the axes of said two similar members, a bolt passing through both shoes axially of said members, a spring engaged on one end of said bolt between a nuton said bolt end and one end of one of said shoes for providing and for holding said shoes under initial compression, and a spring surrounding said body portions and arranged at its ends to exert an outward pressure against each member and cooperating with said a surface for engagement with the internal friction surface of an associated body portion, said shoes having engaged friction surfaces arranged obliquely to the axes of said two similar members, means providing a shoulder at each end of the friction surface of each body portion, each shoe normally engaging one shoulder of the friction surface of the associated body portion, means for providing and for holding said shoes under initial compression, and a spring surrounding said body portions and arranged at its ends to exert an outward pressure against each member and cooperating with said shoes. in offering a resistance to the relative movement of said members toward each other.

13. In a cushioning device for railway cars, the combination of means providing two similar members that are relatively movable toward and away from each other and each member including a body portion having a tapered internal friction surface, said members being. arranged with said body portions in end-to end overlapping relation so that said surfaces are opposed to each other, a pair of friction shoes disposed between said overlapping ends of said body portions, each shoe having an external friction surface engaged l with the friction surface of the associated body l portion but being of a length shorter than the same, said shoes being formed with engaged fric- 20 tion surfaces arranged obliquely to the axes of said two members, means coacting .with said shoes for holding them under initial compression, and a spring surrounding said body portions and arranged at its ends to exert an outward pressure against each member and cooperating with said shoes in offering resistance to the relative movement of said members toward each other.

14. A member for use in a cushioning device of the kind described and comprising a longitudinal body portion having an outwardly extending radial flange at one end defining acentral opening for said end of said member, said body portion having a longitudinally tapered internal 3 friction surface, and means providing shoulders at the ends of said internal friction surface.

15. A member for use in a cushioning device of the kind described and comprising a longitudinal body portion having an outwardly extending radial flange at one end defining a central opening for said end of said member, said body portion having a longitudinally tapered internal friction surface and a substantially semi-cylindrical external surface substantially concentric with the axis of said flange.

16. A friction mechanism assembly for a cushioning device of the kind described comprising a pair of similar members, each having a longitudinal outer, semi-cylindrical surface, a transverse end surface and an oblique surface-between one side of said end surface and the other end of the said semi-cylindrical surface, each mem-- her having a longitudinal central opening, said members being arranged with their oblique friction surfaces engaged with each other so that the said transverse end surfaces are disposed at opposite ends of the assembly, a bolt extending through the longitudinal openings in both members, a nut carried on one end of the bolt and a spring surrounding said end of the bolt and engaged at its ends with said nut and the transverse end of one of said members.

OTHO C. DURYEA.

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