GB2186334A

GB2186334A - Brake shoe assembly

Info

Publication number: GB2186334A
Application number: GB08630249A
Authority: GB
Inventors: Hideyuki Fujinami
Original assignee: Akebono Brake Industry Co Ltd
Current assignee: Akebono Brake Industry Co Ltd
Priority date: 1985-12-20
Filing date: 1986-12-18
Publication date: 1987-08-12
Also published as: JPS62147133A; FR2593866A1; DE3643333A1; FR2593866B1; GB8630249D0; GB2186334B; JPH0156295B2; DE3643333C2

Abstract

A brake shoe assembly comprises a body 22, and a brake shoe 23 having a dovetail 25a slidably insertable into a correspondingly shaped groove 22b in the body, the body having, at least at one end, a securing member 31 pivotable relative to the body in pins 33a, 33b and movable longitudinally, when co-planar with the body, by bolts 32 so as to firmly secure the member to the body. After inserting the dovetail into the groove, or prior to releasing the dovetail therefrom. Its securing member when co-planar with the body will support the shoe by engagement of pin 31c with recess 25c of the dovetail, even when the securing bolts 32 are unscrewed from the body. Thus, a single person can change a heavy brake shoe without fear of injury. <IMAGE>

Description

SPECIFICATION Device for Attaching a Brake Shoe to a Disk Brake The present invention relates to a device for attaching a brake shoe to a disk brake for a railroad car.

Figures 8,9, 10 and 11 show a conventional disk brake for a railroad car. In the disk brake, a pair of brake levers 1 and 2 are coupled to each other centrally by a coupling rod 6 and pins 3a and 3b so that the brake levers are pivotable. An actuator 4 is provided between the ends of the brake levers 1 and 2 and brake shoe assemblies 5 are attached to the other ends of the brake levers 1 and 2 by U-shaped brackets 12a and 12b and coupling pins 13 and 14.

Actuator 4 includes a cylinder 4a, the bottom of which is coupled to one end of the brake lever 1 by a pin 7. A piston rod 4b is similarly coupled to one end of the other brake lever 2 by a pin 8.

One end of a return spring 9 is coupled to the brake lever 1 by a pin 10 and the other end of the return spring 9 is adjustably coupled to the brake lever 2 buy a bolt and nut 11.

The disk brake is attached to the railroad car by supporting the cylinder 4a and the coupling pins 13 and 14 on the chassis 15 of the car. The cylinder 4a is supported by a bracket 16 on the chassis 15.

The upper portions 13a and 14a of the coupling pins 13 and 14 are shaped as forks and support links 18 and 19, coupled at their ends to the upper portions 13a and 14a of the coupling pins 13 and 14, are coupled at their other ends to brackets 1 5a and 15b on the chassis 15 so that the brake shoe assemblies 5 are hung from the chassis 15.

Each brake shoe assembly 5 includes a body 22 and a brake shoe 23. The brake shoe 23 includes a back element 25 and a lining 24 secured thereto. As shown in Figure 11, the body 22 has a pair of brackets 22a on its rear and has a dovetail groove 22b in its front. One end 22c of the dovetail groove 22b is closed, and the other end 22d is open. The backing element 25, to which the lining 24 is secured, has a dovetail 25a, which fits into the dovetail groove 22b. A securing piece 28 has a pair of bolt holes 28a and 28b and a projection 28c.

In each brake shoe assembly 5, the dovetail 25a of the backing element 25 of the brake shoe 23 is inserted into the dovetail groove 22b of the body 22 from its open end 22d. The projection 28c of the securing piece 28 is then inserted into the central portion of the dovetail groove to hold the backing element 25 at its end face, and the securing piece is then tightened onto the body 22 by bolts 30.

Since the dovetail 25a of the brake shoe 23 is inserted upwards into the dovetail groove 22b of the body 22 and the securing piece 28 is tightened on the body 22 by the bolts 30 to attach the brake shoe to the body, it is not only difficult for a single person to attach the brake shoe to the body but also there is a danger that the brake shoe may drop off, injuring the person, when the bolts 30 are pulled out to detach the brake shoe.

According to the present invention, a securing element is always attached to the body of a disk brake assembly, and the brake shoe of the assembly is supported by the securing element even when a new brake shoe is being attached. For that reason, even a single person can safely attach the brake shoe to the body. The brake shoe does not drop off even if bolts for tightening the securing element piece are pulled out of it.

One example of a device according with the present invention will now be described with reference to the accompanying drawings, in which: Figure 1 shows a brake shoe assembly embodying the present invention; Figure 2 shows a brake shoe of the assembly; Figure 3 shows a front view of a securing element; Figure 4 shows a bottom view of the securing element; Figure 5 shows a side view of the securing element; Figure 6 shows a sectional view along the lines 6--6 in Figure 2; Figure 7 shows a view explaining the operation of the assembly; Figure 8 shows a front view of a conventional disk brake for a railroad car; Figure 9 shows a plan view of the disk brake of Figure 8; Figure 10 shows a side view of the disk brake of Figure 8; and, Figure 11 shows the brake shoe assembly of the disk brake of Figure 8.

In the embodiment of the invention shown, the body 22 of the brake shoe assembly of the disk brake has a dovetail groove 22b on one side of the body and on its other side a bracket 22a, as shown in Figure 1. Both the ends 22d of the dovetail groove 22b are open. The body 22 has arc-shaped recesses 22e at the open ends 22d.

As shown in Figures 3, 4 and 5, a securing element 31 has support arms 31 a and 31 bat both sides thereof. The support arms 31 a and 31 b have elongate holes 31 c and 31 d of slender cross section extending in the longitudinal directions of the support arms. An anchoring pin 31e is press-fitted in the securing element 31 and extends transverse to longitudinal directions of the support arms 31a and 31 b. The securing piece 31 has a pair of bolt holes 31f and 319 extending along the length of the support arms 31a and 31b and located at both sides of the anchoring pin 31e. Bolts 32 are inserted into the bolt holes 31f and 31g to tighten the securing piece 31 on the body 22.A pair of support pins 33a and 33b are inserted into the elongate holes 31c and 31d of the support arms 31 and 31 band the tip portions of the support pins are screw-tightened in both the lateral surfaces of the body 22. As a result, the securing piece 31 is supported in such a manner that it can be swung relative to the body 22 and can be moved along the elongate holes 31 c and 31 d.

When the body 22 of the brake shoe assembly is attached to the railroad car, one of the open ends 22d of the dovetail groove 22b is located face-down in the same manner as the conventional disk brake shown in Figure 8.

As shown in Figure 1, the securing piece 31 is put in a suspended state by removing the bolts 32.

As shown in Figure 7, the securing piece 31 is lightly pushed aside so as to be inclined to the backing element 25 of the brake shoe 23 of the brake shoe assembly in order that the dovetail 25a of the back element 25 can be inserted into the dovetail groove 22b of the body 22. After the dovetail 25a is completely inserted into the dovetail groove 22b, the securing piece 31 is swung back to the original position to close the open end 22d of the dovetail groove, and the anchoring pin 31e of the securing piece 31 is fitted into the arc-shaped recess 25c of the backing element 25 to keep the brake shoe 23 from dropping off.

The bolts 32 are then inserted into the bolt holes 31f and 31 g of the securing piece 31 and tightened into the body 22 so that the securing piece is moved up in the longitudinal direction of its support arms 31a and 31b along the length of the dovetail groove 22b of the body 22, and the anchoring pin 31 e is fixed in the arc-shaped recess 22e of the body. As a result, the brake shoe 23 is firmly mounted on the body 22.

The present invention can also be applied to attach the brake shoe of a disk brake of the floating caliper-shaped membertypefora railroad car. In that application, one of the bodies of the brake assemblies of the disk brake is engaged with a piston fitted in a cylinder provided at the rear portion of a caliper-shaped member, and the other body is secured to the front portion of the calipershaped member.

Although both the ends 22d of the dovetail groove 22b are open in the embodiment described above, one of the ends 22d may be closed.

Claims

1. A device for attaching a brake shoe having a lining and a backing element to the body of a brake shoe assembly having a groove extending longitudinally thereof, the device comprising means for engaging the groove to slidably attach the backing element to the body, said means having two ends and a longitudinal axis; a securing element proximate one of the ends; means for mounting the securing element to the body, the securing member being pivotable relative to the body and movable in the direction of the longitudinal axis of the engaging means; and means for securely fastening the securing member to the body while the brake shoe is in use.

2. A device according to claim 1, wherein the mounting means comprises a pair of support arms on the securing member, each having a slender elongate hole in each of the support arms, and a pin extending through each of the elongate holes, whereby the securing member may be pivoted about the pins and moved longitudinally of the engaging means.

3. A device according to claim 1 or claim 2, wherein the attaching means is a dovetail formed on the backing element, for mating with the groove.

4. A device according to claim 3, wherein the securing member has an anchoring pin thereon on which the dovetail rests as the brake is withdrawn from the body.

5. A device for attaching a brake shoe having a lining and a backing element to the body of a brake shoe assembly having a groove extending longitudinally thereof, substantially as described with reference to Figures 1 to 7 of the accompanying drawings.