GB1586200A

GB1586200A - Brake pad assembly

Info

Publication number: GB1586200A
Application number: GB3847977A
Authority: GB
Original assignee: TOKIO Ltd
Current assignee: TOKIO Ltd
Priority date: 1976-09-17
Filing date: 1977-09-15
Publication date: 1981-03-18
Also published as: BR7706196A; JPS5757230Y2; JPS5343184U

Description

(54) BRAKE PAD ASSEMBLY (71) We, TOKICO LTD., a Japanese body corporate of 6-3, Fujimi 1-chome, Kawasaki-ku, Kawasaki-shi, Kanagawaken, Japan, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a brake pad assembly for use in a disc brake.

One prior art brake pad assembly includes a recess formed in peripheral surface of friction material secured to a backing plate of the brake pad with red paint painted in the recess for indicating the limit of wear of the friction material, whereby, the brake pad is replaced when, for example, the red painted recess contacts with a rotatable disc.

However, the recess has usually been formed by cutting or machining operation after the brake pad is formed, thus increasing additional working process and manufacturing costs.

According to the present invention there is provided a brake pad assembly comprising a friction material secured to one side surface of a backing plate, and an indicating member for indicating the limit of wear of the friction material, the indicating member being a distinctive colour with respect to the friction material or the backing plate and being secured on said one side surface of the backing plate at a location where the friction material is not attached.

The present invention will be described more fully by way of example in conjunction with the accompanying drawings, in which: Figure 1 is a front view of a brake pad assembly exemplifying the present invention; Figure 2 is a cross-sectional view taken along line II-II of Figure 1; Figure 3a is a view showing an indicating member; and Figure 3b is a view showing a modified form of the indicating member.

The brake pad assembly 3 shown in Figures 1 and 2 comprises a backing plate 1 and friction material 2 secured on one surface of the backing plate 1. A pair of openings 3a and 3b are formed in the backing plate 1, and when the brake pad assembly 3 is installed in a disc brake a pair of pins (not shown) extend respectively through the openings 3a and 3b to guide sliding movement of the brake pad 3 when the pad is moved toward or away from a rotatable disc (not shown).

A hole 4 is formed in the backing plate 1, and an indicating member 5 having a configuration such as shown in Figure 3a or Figure 3b is secured to the backing plate 1 with stem portion Sa thereof being fitted in the hole 4. The indicating member 5 is located on the side of the backing plate 1 where the friction material 2 is secured thereon and at a location which is not covered by the friction material 2, and is adapted to indicate the limit of wear of the friction material 2. The indicating member 5 projects from the backing plate 1 toward the disc by a predetermined amount, therefore, when the friction material 2 wears by a predetermined amount, the indicating member 5 will contact with the disc in applying brake to notify that the brake pad shall be replaced.

The indicating member 5 is, preferably, formed of a material such as aluminium, synthetic resin or the like which has a hardness lower than the disc to prevent wear or damage of the disc in contacting with the indicating member, and has a good heatresisting characteristics. Further, the indicating member is formed of a material having a distinct colour with respect to the friction material and/or the backing plate or, preferably, is painted in a distinct color such as red. Thus, it is very easy to detect the amount of wear of friction material 2 and to determine the time for replacing the brake pad by simply observing the relative position of the indicating member 5 and the disc from outside of the disc brake.

The hole 4 mounting the indicating member 5 may be formed while the backing plate 1 is formed by press work, thus, no additional cost is required. Further, the indicating member 5 can be mounted on the backing plate 1 easily.

Claims

WHAT WE CLAIM IS:

1. A brake pad assembly comprising a friction material secured to one side surface of a backing plate, and an indicating member for indicating the limit of wear of the friction material, the indicating member being a distinctive colour with respect to the friction material or the backing plate and being secured on said one side surface of the backing plate at a location where the friction material is not attached.

2. A brake pad assembly as claimed in claim 1 in which the distinctive colour is applied to the indicating member.

A A disc brake assembly comprising a rotatable disc and at least one brake pad assembly as claimed in claim 1 or 2, the indicating member being formed of a material whose hardness is lower than that of the disc which the brake pad assembly is engageable during braking.

4. A brake pad assembly constructed and adapted to operate substantially as hereinbefore particularly described with reference to and as illustrated in Figs. 1 to 3a of the accompanying drawings.

5. A brake pad assembly constructed and adapted to operate substantially as hereinbefore particularly described with reference to Fig. 3b of the accompanying drawings.