JPH0231613Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a pad wear detection device that makes it easy to know when to replace pads as wear materials in a disc brake.

A disc brake is a pad that acts as a wear material and is configured to apply braking by pressing both sides of the outer peripheral edge of a disc rotor that rotates together with the wheel. In other words, the pad has an oil cylinder built into the caliper, and during braking, pressurized hydraulic oil is introduced to push out the piston.
Press the inner pad against the disc rotor,
The reaction force causes the caliper to move, and the outer pad is pressed against the disc rotor, resulting in braking.
This moving caliper is attached to the anchor plate 2
It is held by two retainers and is configured to slide on the rail portion during braking. Therefore, the amount of wear on the pads as wear materials is difficult to confirm from the outside, and is only slightly confirmed during inspections or repairs of disc brakes. In addition, conventional devices that allow you to easily check the wear status of pads and when to replace them are ones that have a pointer and a display scale that allow you to visually check the displacement between the anchor plate and caliper due to pad wear. There is. An example is the invention of Utility Model Application Publication No. 55-3072. The device is formed by providing an arrow-shaped pointer made of a thin plate on one of the anchor plate or the caliper, and a bottomed groove-like scale on the thin plate or the main body. However, these conventional displays have the problem that once the vehicle is running, not only the scale but also the scale plate itself cannot be seen due to the adhesion of dust and mud, making it impossible to see any visible signs of wear. There is.

The purpose of this invention is to provide a pad wear detection device for disc brakes that solves the difficulty of checking the amount of pad wear in the conventional example and makes it easy to check when the pads should be replaced. It is.

This invention will be explained in detail based on illustrated embodiments.

FIG. 1 is a cross-sectional explanatory view of a disc brake including the axis of a cylinder with a part cut out. In the figure, 1 is a caliper, 2 is a disc rotor, 3 is a piston, 4 is an inner pad, and 5 is an outer pad. The caliper 1 is placed on the rail 7 of the anchor plate 6 with its sliding portions 8 at both ends perpendicular to the plane of the paper in FIG. 1, and as shown in FIGS. That is, it is formed to be held by two retainers 9.

Furthermore, when braking the disc brake, pressurized hydraulic oil is introduced into the pressurizing chamber 10 formed by the caliper 1 and the piston 3, and the piston 3 is pushed to the right in FIG. to press against. At the same time, the caliper 2 moves in the direction opposite to the direction of the force that causes the inner pad 4 to press the Delos rotor 2 due to this reaction force, and presses the outer pad 5 against the other side of the rotor 2 to generate a braking force. In this case piston 3
When the pressurized state continues, the caliper 1 further moves in the direction of the inner pad 4 by the amount of wear on the outer pad 5. In addition, when the brake is released, the pressurizing chamber 10
With the pressure removed inside, the piston 3 is pulled back by the amount of deformation of the seal 11 during braking due to the elasticity of the seal 11, and an appropriate gap is maintained between the disc rotor 2, the inner pad 4, and the outer pad 5. In other words, the caliper 1 wears the inner pad 4 as much as the outer pad 5 wears each time you brake.
move in the direction. This movement of caliper 1 is the third
This is done while the sliding portion 8 of the caliper 1 shown in the figure slides on the upper surface of the rail 7 of the anchor plate 6.

12 is a protruding piece for detecting the amount of wear on the outer pad 5. The protruding piece 12 is used to determine the wear limit of the outer pad 5 based on the amount of movement of the caliper 1, and to detect when it is time to replace the pad as a wear material. It is formed on the end face in the direction of the inner pad 4, that is, in the direction facing the disc rotor 2. Further, this protruding piece 12 is provided on the same axis as the rail 7 of the anchor plate 6, and the protruding length is formed so that it is on the same plane as the end face of the sliding part 8 of the caliper 1 when the outer pad 5 is completely worn out. Furthermore, the shape of this protruding piece 12 is as follows:
There is no particular requirement other than that the anchor plate 6 has a contact surface 13 that makes tight surface contact with the end surface of the rail 7, and a detection surface 14 that is formed by a plane parallel to this contact surface 13, as shown in FIG. A screw hole is provided on the side end surface of the inner pad 4 of the rail 7 as shown in FIG.
It is desirable to form a shape that can be easily twisted when screwed together.

On the other hand, the end surface of the sliding portion 8 of the caliper 1 in the direction of the inner pad 4, which contrasts with the sensing surface 14 of the projection piece 12, is formed into a plane perpendicular to the sliding surface.

Therefore, when a new outer pad 5, that is, a wear-free outer pad 5, is attached, the detection surface 14 of the projection piece 12
is the inner pad 4 of the sliding part 8 of the caliper 1
A state in which the outer pad 5 protrudes from the end face in the direction by the thickness of the outer pad 5 is presented. When the disc brake is used many times and the outer pad 5 wears out, the protruding length of the sensing surface 14 of the protrusion piece 12 decreases by a length corresponding to the amount of wear, and when the outer pad 5 is completely worn, the sensing surface 14 It is in a state where it is on the same plane as the end face of the sliding part 8 of the caliper 1 in the direction of the inner pad. Therefore, by checking the amount of protrusion of the protruding piece 12, the state of wear of the pad and the timing of replacement can be easily confirmed.

Since this invention is constructed as claimed in the utility model registration claims based on the above-mentioned embodiment, the edge of the anchor plate in the direction of the inner pad can be easily seen from the outside of the disc brake, and
Since the protruding piece is fixed to the anchor plate, it can be used regardless of the movement of the caliper or the accumulation of dust and mud caused by the running of the vehicle.
It is easy to check the protruding pieces. Therefore, it is possible to easily and accurately check the length of the protrusion from the end surface of the sliding portion of the caliper.

At the same time, since the protruding piece is formed on the polygonal side surface, it is easy to engage the wrench for screwing, and it is extremely easy to install, so it is easy to visually check, and at the same time, it is easy to install, and the pad can be replaced accurately. It becomes possible to provide a highly profitable pad wear detection device for disc brakes that allows you to know the timing.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the disc brake including the axis of the cylinder with a part removed, Figure 2 is a side view of the caliper part, and Figure 3 is a cross-sectional view of the caliper's sliding part with part of it removed. Explanatory drawing, FIG. 4 is a front view of a protrusion piece. Explanation of symbols, 1... Caliper, 2... Rotor, 3... Piston, 4... Inner pad, 5
...Outer pad, 6...Anchor plate,
7...Rail, 8...Sliding part, 9...Retainer, 10...Pressure chamber, 11...Seal, 12,1
8... Projection piece, 13... Contact surface, 14... Sensing surface, 15... Screw portion.

Claims (1)

[Scope of utility model registration request] In a rail sliding type caliper for a disc brake, which is equipped with a means for detecting the amount of wear on the pads based on the amount of movement of the caliper relative to the anchor plate due to wear of the pads, the end face of the sliding portion 8 of the caliper 1 in the inner pad 4 direction is slid. The sliding portion 8 is formed on a plane perpendicular to the moving surface.
Anchor plate 6 that is in surface contact with the sliding surface of
A protrusion piece 12 is formed on the end face of the inner pad 4 of the rail 7 on the same axis as the rail 7 and has a protrusion height such that it is on the same plane as the end face of the sliding part 8 of the caliper 1 when the outer pad 5 is completely worn out. , the projection piece 12 is formed by providing a contact surface 13 that makes tight surface contact with the end surface of the rail 7, and a detection surface 14 whose end surface opposite to the contact surface 13 is formed into a plane parallel to the contact surface 13, The contact surface 13 and the detection surface 14 are connected by a polygonal column, and the contact surface 13 is connected to the screw portion 15.
A wear detection device for a pad in a disc brake, which is fixed by screwing.