JPH05248464A - Wear alarming device for friction member - Google Patents

Abstract

PURPOSE:To provide a wear alarming device which performs proper alarming when a wear amount of a friction member reaches a given limit and besides is easily manufactured and high in detecting precision. CONSTITUTION:A wear alarming device for a friction member 2 comprises a member 1 to be braked, a wear member 2 effecting frictional engagement with the member 1 to be braked, and a wear amount detecting element 3 having a conductive member 4 brought into frictional contact with the member 1 to be braked and cut when a wear amount of the friction member 2 attains a given working limit. In which case, the friction amount detecting element 3 has a body 3A formed of an insulating material, such as synthetic resin. Two insertion holes 3a in which the conductive members 4 are inserted are formed in the body 3A along the axial direction of the body 3A. The conductive member 4 is inserted in the insertion hole 3a, the conductive member 4 is bent on the member 1 to be braked side to form an U-shaped loop. By heating the U-shaped loop, the insulating cover 4b of the conductive member 4 and the insulating material of the detecting element 3 are fused and the conductive member 4 is fixed to the detecting element 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction member wear alarm device for warning the wear limit of a friction member of a braking device.

[0002]

2. Description of the Related Art The one disclosed in Japanese Patent Publication No. Sho 53-20623 shows an example of a conventional wear alarm device, and the wear detector of this wear alarm device is a thermosetting resin insulating plate. Is inserted into and fixed between U-shaped conductive members, and then a thermosetting resin is injection-molded around them to form the outer wall body.

[0003]

However, in the above-mentioned conventional device, it is necessary to integrally mold the conductive member with an insulating material such as synthetic resin while positioning the conductive member, and it is difficult to position the use limit. was there. Further, the conventional example has a problem that the detection accuracy tends to vary because it does not operate unless both the insulating material and the conductive member of the detector wear.

[0004]

In order to solve the above problems, in the present invention, a member to be braked, a friction member that frictionally engages with the member to be braked, and the amount of wear of the friction member is predetermined. In a wear alarm device for a friction member, which comprises a wear amount detector having a conductive member that is cut into frictional contact with the braked member when a limit is reached, the wear amount detector is made of synthetic resin or the like. A main body is made of an insulating material, and two insertion holes for inserting the conductive member are provided in the main body along the axial direction of the main body, and the conductive member is inserted into the insertion holes to connect the conductive member to the braked member. Side to form a U-shaped loop, and by heating this, the insulating coating of the conductive member and the insulating material of the detector are fused and the conductive member is fixed to the detector to cause friction. A member wear alarm device is configured.

[0005]

The device of the present invention, unlike the above-mentioned conventional device, does not need to be integrally molded with an insulating material such as synthetic resin while positioning the conductive member, so that the device is easy to manufacture and the positioning of the use limit is easy. , Can be performed with high accuracy. Further, the conductive member of the present invention is prone to wear because it protrudes from the tip of the detector, and also has good conductivity when frictionally contacting the member to be braked to issue an alarm, so the alarm action is reliable and the detection accuracy varies. Also few. Since the device of the present invention can be applied to both a drum brake and a disc brake, it has an advantage that it can be used in a wide range.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention, in which 1 (see FIG. 3) is a member to be braked (disk rotor) which rotates integrally with an axle, and 2 is this member 1 to be braked. The friction member 2 is a friction member (pad) that is frictionally engaged with the friction member 2. The friction member 2b is fixed to the back plate 2a. As the fixing means, various means such as adhesion, riveting, and integral molding can be used.

3 is a wear amount detector, and this wear amount detector 3
Is provided with a conductive member 4 which is cut into frictional contact with the braked member 1 when the wear amount of the friction material 2b reaches a predetermined use limit. That is, the main body 3A of the wear amount detector 3 is formed of an insulating material such as synthetic resin, and two insertion holes 3a parallel to the axial direction through which the conductive member 4 is inserted are formed in the main body 3A. A head portion 3b is formed on the other side, and a body portion 3c having a diameter smaller than that of the head portion 3b is formed on the other side following the body portion 3c.
A plurality of retainer locking grooves 3d are formed in the.

The conductive member 4 is formed by covering the conductive wire 4a with an insulating coating material 4b, inserted into the insertion hole 3a, and bent at the head 3b side to form a U-shaped loop. Both legs of the conductive member 4 are led out to the outside of the body 3c of the detector 3. Reference numeral 4c (see FIG. 3) is a heat-resistant tube for protecting the conductive member 4, and for example, a silicon glass varnish tube or the like is used.

For the main body 3A of the detector 3, for example, a thermosetting molding material is used in which various fillers such as glass fiber and inorganic filler are mixed with silicon resin as a base. The coating material 4b of the conductive member 4 is, for example, an insulating material using heat-resistant fluororesin.
By heating the detector main body 3A through which the core has been inserted, for example, at 300 ° C. for 30 minutes, the insulating material of the detector main body 3A and the coating material 4b of the conductive member 4 are fused and the conductive member 4 is fixed to the detector main body 3A.
Make it stick to A.

To mount the wear amount detector 3 on the friction member 2 as described above, the body portion 3c of the detector 3 is fitted into the mounting hole 2c formed in the back plate 2a to form a plurality of retainer locking grooves. The retainer 5 (see FIG. 3) is fitted in one place of 3d. This body 3c
The plurality of retainer locking grooves 3d provided in the above are for allowing the detector 3 to be attached even if the thickness of the back plate 2a is different. Reference numeral 2d is a hole for accommodating the head portion 3b of the detector 3 formed in the friction material 2b, and 6 (see FIG. 3).
Is a spring for urging the detector 3.

Further, the hole 2d may be a blind hole closed on the braked member 1 side. In this case, the friction material 2
Since the tip of the detector 3 is protected by the friction material 2b until the wear of b reaches the bottom of the blind hole, the durability is improved. Furthermore, the mounting hole 2c is not limited to a circular hole, but may be a deformed hole or a notch. In this case, if the body 3c of the detector 3 is also made to have a different shape,
The detector 3 can be prevented from rotating. And the two insertion holes 3
By positioning so that the direction a and the sliding direction of the braked member 1 are orthogonal to each other, the reliability of the time when the conductive member 4 is cut is improved.

FIG. 4 and FIG. 5 show a second embodiment of the present invention in which a wear amount detector is attached to a friction member.
The same parts as those in the example will be described with the tens place as follows. That is, in this embodiment, the back plate of the friction member 12 is
A holding piece 12 for cutting and raising 12a to hold the wear amount detector 13
e is formed. The friction material 12b is formed with a blind hole 12d that allows the tip portion 13e of the detector 13 to be inserted. The wear amount detector 13 formed in a substantially quadrangle is cut out at four corners of the tip 13e to form a retainer engaging portion 13d, and a conductive member is formed from the rear surface of the detector 13.
14 is outsourced. Ring spring retainer 15
Is the retainer engaging portion 13 of the detector 13 inserted in the friction member 12.
d and four notches 12f formed in the holding piece 12e are engaged and stretched to fix the detector 13 to the friction member 12.

FIGS. 6 and 7 show a third embodiment suitable for a drum brake in which a wear amount detector is attached to a friction member, and parts similar to those of the first embodiment are marked with 20's. The explanation is as follows. In this case, the friction member 22 is
Cross section T of shoe rim (back plate) 22a and shoe web 22g
Welded in a letter shape, and friction material 22b is attached to the outer periphery of the shoe rim 22a.
It is formed by fixing. The wear detector 23 has a tip
The body portion 23c following 23e is formed to have a larger diameter than the tip portion 23e,
Retainer locking grooves 23d are formed on both sides of the body portion 23c. A conductive member 24 is led out behind the detector 23. A blind hole 22d is formed in the friction material 22b to allow the insertion of the tip portion 23e of the detector 23, and the blind hole 22d is formed in the shoe rim 22a.
22c is formed. Detector 23 on shoe web 22g
A stepped notch 22h for holding the body portion 23c is formed. The retainer 25 is attached so as to sandwich the retainer locking groove 23d of the detector 23 inserted in the friction member 22 and the shoe web 22g.

[0014]

The device of the present invention, unlike the above-mentioned conventional device, does not need to be integrally molded with an insulating material such as a synthetic resin while positioning the conductive member, so that it is easy to manufacture, and the positioning of the use limit is also possible. An effect that it can be performed easily and with high accuracy can be obtained. Further, the conductive member of the present invention is prone to wear because it protrudes from the tip of the detector, and also has good conductivity when frictionally contacting the member to be braked to issue an alarm, so the alarm action is reliable and the detection accuracy varies. The effect of less is obtained. Since the device of the present invention can be applied to both a drum brake and a disc brake, it has an advantage that it can be used in a wide range.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a wear amount detector according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a partial sectional view of a disc brake to which the wear amount detector of FIG. 1 is attached.

FIG. 4 is an exploded perspective view showing a second embodiment of the present invention.

5 is a perspective view showing an assembled state of FIG. 4. FIG.

FIG. 6 is an exploded perspective view showing a third embodiment of the present invention.

FIG. 7 is a perspective view showing an assembled state of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Braking member 2 Friction member 2a Back plate 2b Friction material 3 Abrasion amount detector 3A Main body 3a Insertion hole 3b Head part 3c Body part 3d Retainer locking groove 4 Conductive member 4a Conductor wire 4b Coating material 5 Retainer 6 Spring 12 Friction member 13 Wear detector 14 Conductive member 15 Retainer 22 Friction member 23 Wear detector 24 Conductive member 25 Retainer

Claims (1)

[Claims] 1. A member to be braked, a friction member that frictionally engages with the member to be braked, and when the amount of wear of the friction member reaches a predetermined use limit, frictionally contacts the member to be braked and is cut. A wear alarm device for a friction member comprising a wear amount detector having a conductive member, wherein the wear amount detector has a body formed of an insulating material such as synthetic resin, and the conductive member is inserted into the body. Provide two insertion holes along the axial direction of the main body,
A conductive member is inserted into the insertion hole, the conductive member is bent on the side of the member to be braked to form a U-shaped loop, and this is heated to insulate the conductive member and the detector insulating material. A wear alarm device for a friction member, characterized in that the conductive member is fused to fix the conductive member to the detector.