JPH0219639Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a pad wear detection device for a disc brake, which is configured to detect the permissible limit of pad wear and warn the driver.

BACKGROUND ART As shown in FIGS. 2 and 3, a disc brake has a caliper 3 held on an anchor plate 1 by two retainers 2, and a rotor 5 that slides on a rail portion 4 and rotates during braking. It is formed such that it is sandwiched between pads 6 and 7 on both sides for braking. That is, two cylinders 8 are formed in the caliper 3, and a piston 9 is installed in each cylinder 8. During braking, pressurized hydraulic oil is introduced into the cylinder 8, and the piston 9 is pushed out to press one pad 6 (inner pad) against one side of the rotor 5.
At the same time, the caliper 3 slides along the rail portion 4 due to the reaction force, and the other pad 7 (outer pad) is pressed against the other side surface of the rotor 5 to generate a braking force. The conventional technology that detects the wear tolerance limit of the inner pad 6 or outer pad 7 and electrically warns the driver detects the wear tolerance limit of the inner pad 6 that is pressed by the piston 9 and wears out in contact with the rotor 5. This is to issue a warning. This is based on the assumption that, first, the amount of wear on the inner pad 6 and the outer pad 7 is approximately the same, so if you know the wear limit of one inner pad 6, you can estimate the amount of wear on the other outer pad 7; Secondly, it is difficult to directly detect the wear limit of the outer pad 7 in the space inside the caliper 3, and there are other problems such as the fact that the inside of the caliper 3 gets hot, so the electrical wiring needs to have heat resistance and high-temperature strength. It was said that this was due to the fact that

Problems that the invention attempts to solve: However, when the brake is applied, the piston 9
The amount of wear on the inner pad 6, which comes into contact with the rotor 5 under direct pressure, and the amount of wear on the outer pad 7, which comes into contact with the rotor 5 under pressure from the movement of the caliper 3, are different, and which one wears out faster? , it varies from case to case, and there is no particular trend. Therefore, even if the wear amount of only the inner pad 6 is detected and an alarm is issued, the outer pad 7 has already reached the wear tolerance limit.
There is a problem that the braking function may be lost.

Means for Solving the Problems This invention includes a wear detector 10 that is attached to the inner pad back plate 6a and detects the wear tolerance limit of the inner pad 6 by directly contacting the rotating rotor 5 due to wear of the inner pad 6. , is removably fixed to the anchor plate 1, and the caliper 3
A measuring tool 12 is provided on the inner pad 6 side so as to come into contact with the indicating tool 11 fixed to the caliper 3 to detect the allowable wear amount of the outer pad 7 when the caliper moves. By connecting and quickly breaking or destroying either the wear detection tool 10 or the calibration tool 12, the alarm circuit is activated.
It is an object of the present invention to provide a pad wear detection device for a disc brake which solves the above-mentioned problems by warning the driver by lighting up a warning lamp or the like.

Function The pad wear detection device in this invention has the following features:
Since the wear detector 10 directly detects the wear tolerance limit of the inner pad 6, if the inner pad 6 quickly reaches the wear tolerance limit, an alarm circuit is activated and a warning lamp or the like is lit to warn the driver. Also, if the outer pad 7 wears quickly, the detection tool 12
is destroyed, the alarm circuit is activated, and an alarm is issued. In other words, an alarm is issued when any of the pads quickly reaches its wear tolerance limit. Further, the measuring tool 12 is attached to the inner pad 6 side of the caliper 3, and the wiring of the measuring tool 12 and the wear detection tool 10 is led to the outside of the caliper 3, thereby facilitating connection of the alarm circuit.

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

FIG. 1 is an explanatory diagram of the mechanism of this invention. In the figure, 1 is the anchor plate, 3 is the caliper, 5 is the rotor, 6 is the inner pad, 7 is the outer pad, 8 is the cylinder, 9 is the piston, 10 is the wear detector, 11 is the indicator, 12 is the measuring tool, and 13 is the warning The lamp 14 is an alarm circuit. Wear detection tool 1
0, the inner pad 6 is riveted or screwed, and is removably engaged with and fixed to the side end of the inner pad back plate 6a to be packed up. That is, as shown in FIG. 4, a through hole 15 is provided in the parallel portion of the side end of the inner pad back plate 6a, an engaging tool 16 is inserted into the through hole 15, and a wear detection tool is inserted into the engaging tool 16. 10 is inserted.

As shown in FIG. 6, the engaging tool 16 has a cylindrical main body with a flange 17 bent outward at one opening edge, and a flange 17 formed from the vicinity of the other opening edge. An engaging protrusion 18 is provided that is raised upward toward the inside of the cylindrical shape, and a plurality of vertical divisions parallel to the vertical axis are provided in the opening including the flange 17, so that the opening including the flange 17 is provided with a plurality of vertical divisions parallel to the vertical axis. is formed so that it can be reduced in diameter and restored. The engaging tool 16 is inserted into the through hole 15 from the inner pad 6 side, and the flange 17 is inserted into the inner pad 6 side.
The inner pad is formed to engage with the surface of the side inner pad back plate 6a.

Further, the wear detection tool 10, as shown in FIG.
An engagement recess 20 with a reduced diameter is provided in the main body made of an insulating material in the form of a cylinder, and a parallel part 19 formed in a parallel cylinder is provided across the engagement recess 20. The metal wire 21 is bent into two parallel wires separated from each other, and in order to prevent the metal wires from being short-circuited, an insulating material made of a brittle material, such as hardened powder material, is used to prevent the metal wires from being short-circuited. Fill and set. Furthermore, connecting edges 22 of two parallel bent metal wires are fixed at a position slightly lower than one of the opening surfaces, and the two parallel ends are guided out of the main body and connected to the alarm circuit 14. Connecting. This abrasion detection tool 10 is constructed by inserting the open end provided with the connecting edge 22 into the engagement tool 16 from the back side of the surface provided with the inner pad 6, and opening the opening including the flange 17 at the parallel part 19 of the abrasion detection tool 10. The engagement protrusion 18 is engaged with the engagement recess 20 and fixed in the through hole 15 in a locked state in the returning direction. In addition, for unfitting, push down the engagement protrusion 18 to disengage the engagement and pull it out. In this engaged state, the open end of the wear detector 10 provided with the connecting edge 22 protrudes from the surface of the inner pad back plate 6a, and the height of the protrusion is set at the wear tolerance limit position of the inner pad 6.

The measuring tool 12 is formed in the same manner as the wear detecting tool 10 in the inner pad 6, as shown in FIGS. 8 and 9. In the anchor plate 1,
A mounting base 23, which is a width plate bent into an L-shape, is screwed and fixed to the edge in the same direction as the wear detection tool 10, and the measuring tool 12 is detachably fixed to this mounting base 23. . That is, anchor plate 1
Attach the retainer 2 to the side surface of the retainer 2 attachment portion on the inner pad 6 side, that is, the end surface of the slide portion of the caliper 3 of the anchor plate 1 on the inner pad 6 side so that the ridgeline of the attachment portion of the retainer 2 is parallel to the side surface of the width plate. Screw the stand 23 on. Further, a stepped through hole 24 is provided in the width-like plane of the mounting base 23.
The stepped through hole 24 has a shoulder portion 25 formed with a larger diameter loosely fitted at the end edge of the parallel portion 19 in the opposite direction to the connecting edge 22 of the wear detector 10, as shown in FIG. It is formed by providing a large diameter portion into which the parallel portion 19 is inserted and a small diameter portion into which the parallel portion 19 is slidably fitted, and is engaged with the shoulder portion 25 of the measuring tool 12 (wear detection tool 10) in contact with the step. The recess 20 is provided so as to slightly protrude from the surface of the mounting base 23, and the slightly protruding engagement recess 2
0 so as to be fixed by engaging an elastic stopper, such as a snap spring. In addition, the indicator 11 is
A thick width plate is detachably fixed to the end face of the caliper 3 on the inner pad 6 side in the moving direction. In this case, the lower end edge of the width-like plate is installed at a position slightly apart from the plane of the mounting base 23, and as the caliper 3 moves, the lower end edge of the width-like plate of the indicator 11 is moved to the parallel part 20 of the measuring tool 12. It is provided so that it breaks in a shear shape. Further, the distance between the indicating tool 11 and the measuring tool 12 is set so that the distance between the indicating tool 11 and the measuring tool 12 is within the wear tolerance limit of the outer pad 7. The alarm circuit 14 includes an alarm relay circuit in which the metal wire 21 of the wear detection tool 10 and the measurement tool 12, a relay solenoid, and a power source are connected and wired in series as shown in the figure, and an alarm relay circuit that is turned off and de-energized when the relay solenoid is energized. It consists of a switch that is turned on at times, an alarm lamp 13, and an alarm lamp circuit whose power source is wired as shown. Therefore, if any of the metal wires 21 of the wear detection tool 10 and the measuring tool 12 are cut, the warning lamp 13 attached to the driver's seat lights up to warn that the pads have been worn to the wear limit. It's getting old.

Effects This invention is based on the above-mentioned embodiment and is configured as claimed in the utility model registration, so a warning is given when either the inner pad or the outer pad reaches the wear tolerance limit earlier, so that when the warning occurs, It is possible to prevent a situation in which any one of the pads has already exceeded its wear tolerance limit. Furthermore, the measuring tool can be installed by simply providing a screw hole on the end face of the anchor plate and the caliper in the same direction, so it can be installed on existing vehicles. Further, since the wear detection tool and the detection tool are provided close to each other near the inner pad using a mounting base, it is possible to provide a wear detection device for a disc brake with easy wiring of the alarm circuit and less damage.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the mechanism of this invention, Fig. 2 is a front view of the disc brake with part removed, Fig. 3 is a sectional view of the disc brake with part removed, and Fig. 4
The figure is a plan view of the inner pad, Figure 5 is a front view with a part removed, Figure 6 is an enlarged sectional view of the through hole, Figure 7 is a sectional view of the wear detection tool, and Figure 8 is the measuring tool. FIG. 9 is a side view of the installation front explanatory view. 1... Anchor plate, 3... Caliper,
5...Rotor, 6...Inner pad, 6a...
... Inner pad back plate, 7... Muter pad,
10... Wear detection tool, 11... Indicator, 12...
Calibration tool, 13...Alarm lamp, 14...Alarm circuit, 15...Through hole, 21...Metal wire, 23...
Mounting base, 24...stepped through hole, 25...shoulder.

Claims (1)

[Claims for Utility Model Registration] 1. Inner and outer pads 6, 7 located opposite to each other on both sides of the outer periphery of the rotor 5, and both pads 6, 7 that are slidably attached to an anchor plate that is fixedly held.
It consists of a floating caliper 3 disposed to cover the caliper 3, and a piston 9 inserted into a cylinder 8 formed in the caliper 3. The pushed-out piston 9 presses the inner pad 6 against the inner surface of the rotor 5, and the caliper, which is pushed inward by the pressurized hydraulic oil and slides, presses the outer pad 7 against the outer surface of the rotor 5. In the disc brake configured as shown in FIG. a wear detector 10 which is adapted to cut the inner metal wire 21 when the outer pad 7 is worn to the wear limit; The measuring tool 12, which has come into contact with a part of the caliper 3 that is moving and is broken, and the internal metal wire 21 is cut, and the detecting tool 10 and the internal metal wire 21 of the measuring tool 12 are connected in series. What is claimed is: 1. A wear detection device for a pad in a disc brake, comprising: a connected alarm circuit which issues an alarm when any metal wire is cut; 2. The wear detection device according to claim 1, wherein the detection tool and the calibration tool are detachably attached to the back plate 6a of the inner pad 6 and the anchor plate 1, respectively. 3 The calibration tool 12 is formed by bending a width plate into an L-shape, and the caliper 3 is attached to a mounting base 23 fixed to the anchor plate.
When the outer pad 7 is worn down to the wear limit and the caliper moves inward in response to this, the calibration tool is attached to the inner side of the support 11 fixed to the inner end surface of the caliper. Claim 1 of the utility model registration, which is characterized in that it is designed to break when it comes into contact with a tool.
The wear detection device according to item 1 or 2.