US2206676A

US2206676A - Brake beam

Info

Publication number: US2206676A
Application number: US222828A
Authority: US
Inventors: Schaefer Frederic
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-08-03
Filing date: 1938-08-03
Publication date: 1940-07-02
Anticipated expiration: 1957-07-02

Description

BRAKE BEAM Filed Aug. 3, 1938 2 Sheets-Sheet 1 J VENTOR.

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BY 3 wlrufssfs WO QMZV r fla if??? 4 ATTORNEYS.

July 2, 1940. SCHAEFER 2,206,676

BRAKE BEAM Filed Aug. 5, 1938 2 Sheets-Sheet 2 I E l- WITNEJJES INVENTOR.

BY M 4 Z M. a

'q ATTORNEYS.

Q Patented July 2, 1940 2,206,675

UNITED STATES PATENT OFFICE BRAKE BEAM Frederic Schaefer, Pittsburgh, Pa. Application August a, 1938, Serial No. 222,828

9Claims. (01. 188-228) This invention relates to railway brake beams, member are brake heads each of which has a and more particularly to truss type beams. laterally projecting tongue that extends into the As a factor in making railway rolling stock adjoining ,end of the compression member in lighter it is desirable to decrease the weight of which it is tightly wedged in place by engagebrake beams, but heretofore no practical way ment with the inner surface thereof. For this 6 of doing it without unduly weakening the beam purpose each end of the compression member has been found. Another of the disadvantages preferably diverges, and the tongue is tapered so of brake .beams today is the loose fit between the that it will have a wedge fit with the diverging brake heads and compression member which walls. At the-base of the tongue the head is prooccurs after a brief period of service. This is vided with a shallow lateral recess for tightly re- 10 chiefly due to the clearance that is necessary to ceiving the end of the compression member. The insure that the compression members will fit in inner surface of the nut that is threaded on each the deep sockets of the brake heads, and to the end of the tension member is convex and is irregularities in the adjoining surfaces whereby seated in a concave socket in the adjoining brake the heads are permitted to rock on the ends of head so that it aligns itself with the force exerted the compression member. Furthermore, the ends upon it. The threaded end of the tension memof the compression member are sheared, freber is strengthened by increasing its diameter bequently on a slight bias, which often leaves them fore threading so that its diameter at the root with fins or rough edges, and the socket in the of its threads is substantially the same as the :0 head is also likely to be covered with scale or a diameter of the rest of the tension member. sandy film. As the entire brake beam structure The preferred embodiment of the invention is is generally held together only by nuts at the ends illustrated in the accompanying drawings in of the tension member and by rivets or a key conwhich Fig. 1 is a fragmentary plan view of my necting the strut to the compression member, it brake beam; Fig. 2 is a fragmentary side view of has not been possible to hold the component parts one end of the compression member and head; 25 rigidly together. Fig. 3 is a side view of the strut; Fig. 4 is an en- The bearing area between the strut and tension larged end view of the beam showing a brake head member is quite small, whereby the strut someapplying a shoe to a wheel; Fig. 5 is an enlarged times cuts into the tension member. Due tothe plan view of the brake head; Fig. 6 is a vertical diameter of the threaded ends of the tension section of the head taken on the line VI--VI of to member at the root of the threads being less than Fig. 1; Fig. '7 is a vertical section of the compresthe diameter of the rest of the member, the crosssion member taken on the line VII-VII of Fig. 1; sectional area of the ends is materially decreased Fig. 8 is an enlarged longitudinal section through whereby the tension member occasionally breaks the brake head taken on the line VIIIVIII of at the root of the threads. This danger is in- Fig. 1; and Fig. 9 is an enlarged side view of a it creased when the nut does not sit squarely against threaded end of the tension member and the nut its supporting surface on the adjoining brake that is threaded onto it. head, and thereby exerts a bending strain on the Referring to Fig. 1 of the drawings, a truss type end of the tension member. brake beam is formed from a compression mem- 40 It is among the objects of this invention to her i which carries at each end a brake head 2 Mil provide a relatively light weight brake beam to which the ends of a tension member 3 are without sacrifice of strength, a more permanently connected. The central portion of the tension rigid brake beam, and a longer-life beam. member is spaced from the cambered compres- In accordance with this invention abrake beam sion member in the usual manner by a strut 4.

is formed of a compression member having spaced This general construction of the beam is the same t5 top and bottom walls joined by a side wall beas standard beams now in use, my invention havtween which one end of a strut'has a wedge fit. ing to do with improvements in the component The other end of the strut is provided with a parts of the beam and. in the way in which they large bearing area for the tension member so are connected together. Thus, as shown in Fig. 7,

that the strut will not cut into it. The compresthe compression member has spaced top and 50 sion member is made substantially C-shape in bottom walls 6 joined by an integral side or back cross section from relatively thin material and wall 1, and is preferably generally U- or C-shape is strengthened by thickening its edge portions in cross section. The compression member is and also, preferably, spaced portions of its back made from a rolled section which is most suitwall. Carried by the ends of the compression ably a .40.50 carbon steel because of its higher by thickening the spaced longitudinal edges 8 of the compression member along their inner surfaces. This thickening also'reinforces the edges against bending in any direction. The compression member is also strengthened, without adding materially to its weight, by providing the inner surface of its back wall with vertically spaced raised portions that form interior longitudinal ribs 9.

Another-feature of this invention is that the brake heads 2 are so connected to the ends of the compression member that the connection remains rigid indefinitely. Accordingly, each brake head, .instead of being provided with the usual socket for receiving an end portion of the compression member, is provided with a laterally projecting tongue I I (Fig. 5) that extends into the adjoining end of the 'compressionmember and frictionally engages its inner surfaces.

Preferably, as shown in Figs. 1 and 8, the end portions of the compressionmember walls diverge toward the ends of the member, and the brake head tongue tapers or converges toward its free end at substantially the same angle. The outer surface of the tongue conforms in contour to the adjoining inner'surface of the compression member (Fig. 7), and these two members are of such size as to require the tongue to be driven into the compression member whereby a wedge fit is provided. To further rigidly secure the head and compression member together, the head is provided with a shallow recess I! at the baseof the tongue for receivingthe end of the compression member which is thereby wedged in the recess between its inner and outer walls (Figs. 5, 6 and 8). To insure engagement of as much area as possible of the adjoining surfaces of the compression member and tongue, the end portions of the compression member are tapered or coned in a heading machine and their end walls are squared for bearing fiat against the heads. The recess I2 in each head is preferably shaped with a hard baked core to assure a true and flat bearing surface, and as the recess is shallow it can be readily cleaned of sand and scale. Due to the crosssectional C-shape of the compression member, the brake head tongue is prevented from being forced out of the member through the space between its edges 8 (Fig. 7).

Each brake head is provided with the usual opening I5 through whichone end of tension member 3 extends. It is another..,feature of this invention that the nuts l6 that are threaded on the projecting ends of the tension member always seat properly against the brake head. Accordingly, the inner or bearing surface of each nut is convex, as shown in Fig. 9, and forms a portion of a sphere. This surface will hereinafter be referred to as spherical, although it is not a complete sphere. Likewise, as shown in Fig. 5, the surface I! of the brake head against which this nut bears is concave to form a spherical seat for the nut which therefore can have universal movement thereon. This construction aeoacve permits the nuts to seat flat against the heads without lateral strain on the end portions of the tension member, regardless of factors that might otherwise prevent proper seating of the nuts. In addition, as the beam deflects under load, the tension rod nut and head assembly is self-aligning to take care of whatever change may take place in their relation.

To avoid fracture of the tension member at the root of its threads, heretofore due to a smaller cross-sectional area at that point, its end portions I8 are upset before threading by an amount preferably at least as great as the depth of the threads. Consequently, when these enlarged end portions are threaded, the roots of the threads are substantially in line with the outer surface of the remainder of the rod. In other words, the

diameter of the tension member at the roots of .from cutting into the tension member. As shown in Figs. 1 and 3, the other end of the strut is provided .with laterally projecting lugs 22 which are so shaped as to conform to the inner surface of the compression member behind thickened edges 8. The strut can therefore be connected to the compression member only by inserting .it therein from one end of the member. Lugs 22 are slightly wider than the space between the top and bottom walls of the compression member so that the strut has to be driven into the member, thereby providing a wedge fit between them which helps rigidify the entire brake beam.

The strut is further held in place by the usual rivets 23 extending through lugs 22 and the back wall of the-compression member. The struts bearing area for the inclined brake lever (not shown) is materially increased as shown at 24 in Figs. 1 and 3. In this respect the strut is the same as that shown in my copending patent application Serial No. 161,397, filed August 28, 1937 which matured into- Patent No. 2,132,222 on October 4, 1938.

According to the provisions of the patent statutes, I have explained the principle and construction of my invention, and have illustrated and described what I now consider to be its best embodiment. However, I'desire to have it understood' that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. A brake beam comprising a compression member having spaced top and bottom walls joined by a side wall, the inner surfaces of the end portions of said walls diverging toward their ends, and a brake head carried by each end of said member, each head being provided with a laterally projecting tongue extending into the adjoining end of the compression member, and the outer surface of said tongueconverging toward its inner end with said wall and tongue surfaces engaging each other with a wedge fit.

2. A brake beam comprising a compression member having spaced top and bottom walls joined by a side wall, the inner surfaces of the end portions of said walls diverging toward their ends, and a brake head carried by each end of said member, each head being provided with a laterally projecting tongue extending into the adjoining end of the compression member, and the outer surface of said tongue converging toward its inner end and conforming in contour to said diverging wall surfaces whereby said wall and tongue surfaces frictlonally engage each other with a wedge lit.

3. A brake beam comprising a compression member having spaced top and bottom walls Joined by a side wall, the inner surfaces of the end portions of said walls diverging toward their ends, and a brake head carried by each end of said member, each head being provided with a laterally projecting tongue extending into the adjoining end of the compression member, the outer surface of said tongue converging toward its inner end with said wall and tongue surfaces engaging each other with a wedge fit, and each head having a lateral recess at the base of its tongue for tightly receiving the end of the compression member.

4. A brake beam comprising a compression member having spaced top andbottom walls Joined by a side wall, and a brake head carried by each end of said member, each head being provided with a laterally projecting tongue extending into the adjoining end of the compression member and enga ing said walls, a tension member connected to the brake heads, and a strut spacing said members apart, one end ofthe strut being tightly wedged between the top and bottom walls of the compression member.

5. A brake beam comprising a compression member having spaced top and bottom walls joined by a side wall, and a brake head carried by each end of said member. a tension member connected to the brake heads, and a strut spacing said members apart, one endof the strut being tightly wedged between the top and bottom walls of the compression member.

6. A brake beam comprising a compression member having spaced top and bottom walls joined by a side wall, and a brake head carried by each end of said member, a tension member connected to the brake heads, and a strut spacing said members apart, one end of the strut being tightly wedged between the top and bottom walls of the compression'member and the opposite end of the strut having a relatively long bearing surface for the tension member, said surface having a semi-circular portion in cross section engaging the tension member.

'7. A brake beam comprising a compression member substantially c-shape in cross section and having materially thickened longitudinal edges, and a brake head carried by each end of said member, each head being provided with a laterally projecting tongue extending into the adjoining end of the compression member and tightly engaging its inner surface.

8. A brake beam comprising a compression member substantially G-shape in cross section, the longitudinal edge portions of said member being thickened interiorly and the innermost surface of the member being provided with spaced raised portions forming interior longitudinal ribs.

9. A brake beam comprising a compression member substantially c-shape in cross section. the longitudinal edge portions of said member being thickened interiorly and the innermost surface of the member being provided with spaced raised portions forming interior longitudinal ribs, and a brake head carried by each end of said member, each head being provided with a laterally projecting tongue extending into the adjoining end of the compression member and tightly engaging its inner surface.

FRIEDERIC