US1876077A - Brake - Google Patents

Description

Sept. 6, 1932. R s SANFQRD 1,876,077

BRAKE Filed Sept. 4, 1928 A TT ORNEY Patented Sept. 6, 1932 UNITED STATES PATENT OFFICE ROY S. SANFORD, OF SOUTH BEND, INDIANA, ASSIGNOR TO BENDIX BRAKE COMPANY, F SOUTH BEND, INDIANA, A CORPORATION OF ILLINOIS BRAKE Application led September 4, 1928. Serial No. 303,716.

This invention relates to brakes and is illustrated as embodied in an internal expanding brake for an automobile. An object of the invention is to provide the brake with simple positioned by a device carried by the backing plate of the brake and which is readily adjusted from the outside of the brake and which is shown in the form of an eccentric engaging the lever. j

The lever is preferably forked to engage the articulating pivot, although any suitable construction giving the necessary guide surfaces on the lever can be used, and it may be arranged either with the slot between the forked arms extending in the direction of movement of the articulating pivot, in which case the fork embracesthe pivot with substantially no clearance, or at right angles to the direction of movement of the pivot, in

which case the fork has suiicient clearance to allow the brakeapplying movement of the articulating pivot.

The above and other objects and features of the invention, including details of the construction of the novel stop, will be apparent from the following description of the illustrative embodiments shown in the accompanying drawing, in which: Figure 1 is a vertical section through the brake just inside the head of the brake drum and showing the brake shoes in side elevation; i

Figure 2 is a partial section through the brake on thev line 22 of Figure 1 and showing some of the details of construction; and Figure 3 is a detailed section showing a modification, and being in effect a section on the line corresponding to the line A-A of Figure 2.

The brake in which the invention is shown embodied includes a rotatable drum 10, at the open side of which is arranged -a support such as the usual backing plate 12 and within `which is arranged the friction means of the brake. rlhe frictionmeans of this particular brake includes a iioating primary shoe 14 connected by a floating articulating l joint or pivot 16 to a secondary shoe 18 anchored on a ixed pivot 20, together with an auxiliary shoe 22 anchored on a fixed pivot 24. The brake is applied by means such as a double cam 26 which forces shoes 14 and 22 apart against lresistance of a return spring 28, whereupon the shoe 14 forces the shoe 18 against the drum against the resistance of an auxiliary return spring 30. In this drawing I have shown my novel stop y used to determine the idle position of the articulating pivot 16, which is preferably grooved adjacent the endnearest the backing plate to yform an end flange 34.

In the arrangement of Figures 1 and 2 the stop includes a bell crank lever 36 of stamped steel mounted on a pivot 38 carried by the backing plate 12 and which is forked at its end to interlock with the flange 34 of the pivot 16 to prevent axial movement of the pivot, the forked portion of the lever embracing the groove in the end of the pivot 16. The space between the arms of the fork is slightly greater than the diameter of the grooved portion of the nivot 16 so that there is a clearance at one side of the grooved portion of ,the pivot. When the brake is released, the spring 30 pulls the grooved portion of the articulating pin 16 a ainst the upper side of the fork in the end o the lever 36, thus determining the idle position of the shoe 18. YThe position of the lever 36 may be adjusted to vary the clearance of the shoe 18 with respect to the brake drum by means Such as an eccentric 40 extending through the backing plate 12 so that it can be operated from outside the backing plateV and which engages the end of the bell crank lever opposite the articulating pin 16.

In the arrangement of Figure 3 there is a lever 136 mounted on a pivot 138 and having its position determined by an eccentric 100 140, in the same general manner asfdescribed above, but in this case the lever 136 has its slot 'arranged in the direction of movement of the articulating pivot 1,6 so thatit closely embraces the grooved portion -of the pivot land serves as aguide therefor.

While two illustrative embodiments have been described in detail, it is not my inten tion to limit the scope of the'invention to those' particular embodiments or otherwisev than by the terms of the appended claims.

I claim:

1. A brake comprising pivotally connected friction means, a pivotally mounted bellcrank lever havin one arm engagin the pivotal connectiongtogether with an adjustable device engaging and determining the position of the other arm of said lever.

2. A brake comprising friction elements connected'by a pivot, a pivotally mounted bellcrank lever with one arm having a sliding engagement 'with the pivot, together with an adjustable eccentric engaging and determiningthe position-of the other arm of said lever. y

3. A brake comprising shoes connected by a. floating pivot having a grooved end, in

. combination with a positioning lever havinlg other end. j. 4. A brake comprising shoes connected by one end embracing and interlocking wit said grooved end, and an adjustable eccen- I tric'A forl pivotally` mounting the lever at its a floating pivot having a grooved end, in combination with a positioning lever having one end embracing and interlocking with said grooved end, and an adjustable eccentric engaging the other end.

5. A brake comprising shoes connected by a floating pivot, a lever havingone end embracingthe pivot with substantial clearance and an adjustablefeccentric providing a pivotal support for the other end of the lever. l

I. 6. A brake comprising shoes connected lby a floating pivot,` a bell crank lever having its 4knee supported on a iXedl pivot and one end embracing the floating pivot Withsubstantial clearance and an adjustable eccentric adaptable l-for engagement with the other end of the lever.

vIn testimony whereof, I have hereunto si ed m name.

gn y ROY S. SANFORD.

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