US1924113A - Brake shoe - Google Patents

Description

. Aug. 29, 1933. RFEVANS muxa'skoz Filed larch 20, 1931 Patented Aug 29, 1933 BRAKE SHOE Edwin E. Evans, Chicago, 111. Application March 20, 1931. Serial No. 524,011

2 Claims.

formed from a rolled section of standard shape.

and provided with an integral actuating portion. It is an additional object to provide a shoe of this character in which the actuating face is integrally connected to and fully supported by a web of the rolled section.

It is a further object to provide a shoe having an integral hardened actuating wear face.

Other and further objects will appear as the description proceeds. I

I have shown certain preferred embodiments of my invention in the accompanying drawing,-

in which- Figure 1 is an elevation of my improved shoes applied to a brake assembly, the brake drum being cut away to show the interior parts;

Figure 2 is a similar view of a single brake shoe on an enlarged scale;

Figure 3 is a view of Figure 2 as seen from above; v

Figure 4. is a view of Figure 2 as seen from below;

Figure 5 is a view of Figure 2 as seen from the left;

Figure 6 is a section of Figure 2 on line 6-6;

Figure '7 is a section of Figure 2 on line 7-7; Figure 8 is a section similar to Figure 6 showing a modified form of construction; and

Figure 9 is a view similar to Figure 8 showing a further modified form.

In Figure 1 the backing plate 11 is shown provided with bolts 12 by which it may be so cured to a steering knuckle (not shown). The

backing plate 11 carries a housing 13 which sup ports an adjustable brake shoe pivot pin 14. The bearing ends 15 of the shoes 16 pass through slots in the housing 13 to engage in grooves in the pin is. The shoes 16 are T-shaped in cross section, being provided with the cylindrical flange 17 and the inwardly extending web 18. The flange 17 carries the brake lining 19 adapted to engage the brake drum 20. The springs 21 are connected at one end to the shoes 16 and at the other end to the backing plate 11 so that they serve to retract the shoes from engagement with the brake drum 20. The springs may impart angular thrusts to the shoes tending to urge them toward the backing plate, .and the webs of the shoes may have raised portions 40, 10 for engaging the backing plate. The portions 40 therefore require 'machiningof only small surfaces.

The lower ends of the shoes, as shown, are provided with bent up ends 22 which serve as actuating faces to engage the operating cam 23 carried by brake operating shaft 24. Both the web 16 and flange 17 are bent or forged so that the flange throughout its extent, including the bent up portion, is integrally and permanently connected with the web.

In one method of manufacture, the shoes are formed from straight T-bars. These bars are first sawed'to give pieces of the proper length for the desired shoes. Then the webs have outer portions adjacent the ends of the blanks cut 5 away on lines such as to eliminate excess metal. The ends of the blanks are then bent up, the metal of the web being forged or swaged to bring it to the form shown in the drawing. There are no edges to be joined by the forging or swaging and there is no welding. The metal of the web is caused to flow to form the continuous web shown. I

In the form shown the web 16 is of a depth g5 similar to the depth of the wear face 22 so that this face is supported by the web throughout its height. The flange portion of the blank which forms the .actuating face 22 is also deformed during the forming operation, being curved in cross section as clearly shown at 23 of Figure 4. Also where the shoe is to be used in a structure in which the shoe is in a plane at an angle to the plane of the swiveling axis, the curved portion of the bearing face may be formed on an angle as best shown in Figure 5. Due to this curved formation the edges of the flanges extend inwardly as shown at 24 and 25 of Figure 5.

The upper or pivot end 15 of the shoe may be formed by the same type of operations as the acm tuating end. The pivot end 15 has an end face 26 cut on an angle as shown in Figure 3 so as to fit in the angular grooves in the pivot pin 14 whereby axial movement of the pin will adjust the shoes.

A portion of the web 16 is shown bent over to give a bearing face 2'7 for a centralizer 28. This centralizer is shown in Figure 1 as a conical headed stud threaded into the backing plate 11.

The shoes may be suitably heat treated as plete. The pivot ends and wear faces 23 may be hardened to resist wear, by the cyanide process 7 for example.

While the shoes have been described so far as being formed of T-shaped rolled section, it may be found desirable in large sizes and with wide shoes to use sections having a plurality of inwardly extending webs. Figure 6 shows a section having a flange and a pair of spaced webs 31 and 32. Figure 9 shows a channel section with a base 33 and legs 34 and 35; Sections such as these with a pluralityof webs permit strengthening the flangeat a' plurality of 'points and also permit equivalent rigidity with webs of less depth than would be necessary with a'fl'esser number of webs. The webs of less deptlipermit greater clearances in the assembly and also facilitate the forming operations of the ends of the shoes.

The forms of construction shown are to be taken as illustrative only, as the improved brake shoe is capable of variations and' chan e to meet differing requirements. and I contemplate such desired, after the forming operations are comchanges and modifications as come within the spirit and scope of the appended claims.

I claim: V

1. A brake shoe comprising a unitaryrrolled section having a cylindrical flange and an inwardly extending web, a continuous portion of the flange integrally connected to the web throughout its extent being bent inwardly to form a cam contact face, the web being of a depth substantially'equal to the depth of the inwardly extending flange and directly, supporting said flange.

2. A brake assembly comprising a unitary rolled section brake shoe having a cylindrical flange and an inwardly extending web, a continuous portion of the flange integrally connected to the web throughout its extent being bent inwardly, the inwardly extending flange forming a cam contact face, said face being hardened to resist wear, and a brake operating cam engaging said surface.

EDWIN R. EVANS.

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