JPH10252791A - Abrasion alarming device for lining - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an abrasion alarming device for a lining to perform reliable mounting by preventing a fall and rotation of a sensor through simple means. SOLUTION: An abrasion alarming device for a lining comprises a sensor body 1 which is fittingly inserted and mounted into a mounting groove 14, on the back plate 11 of which a sensor 20 is arranged, or a hole 21; and a single conductor 26 which is disposed in the sensor body 21 and at the tip of which is folded to form a fold part 27. The fold part 27 is fixed in the wear limit position of a lining 12, and a deformed part 24 formed integrally with the sensor body 21 is brought into a non-rotatable contact with the lining 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lining wear warning device which electrically detects a wear limit position of a lining constituting a braking member such as a friction pad or a brake shoe and warns a driver.

[0002]

2. Description of the Related Art In recent years, there has been proposed a lining wear warning device which alerts a driver by a warning sound or a warning light when the lining reaches a wear limit. In this device, various sensors are attached to the back plate that constitutes the braking member,
As the lining wears and the sensor frictionally contacts the opposing rotor or brake drum and the conductor is cut, the sensor electrically detects the lining's wear limit, and based on this detection signal, an alarm sound or warning light Is issued.

[0003]

The sensor must be securely mounted so that it does not fall off due to the vibration of the braking member or the like, and the sensor does not rotate when it comes into frictional contact with the rotating rotor or brake drum. It needs to be attached. Since the conventional means for preventing the sensor from falling off and the means for preventing rotation are provided between the back plate and the sensor, the mounting structure of the sensor becomes complicated and many assembling steps are required. Further, it has been pointed out that high processing accuracy is required.

The present invention has been made in view of the above points, and an object of the present invention is to prevent a sensor from falling off and rotating by a simple means and securely attach the lining. It is to provide a device. Still another object of the present invention is that high processing accuracy is not required with a simple structure,
An object of the present invention is to provide a lining wear warning device.

[0005]

The invention according to claim 1 is
In a lining wear warning device in which a sensor is attached to a part of a back plate and the wear limit of the lining fixed to the back plate is electrically detected by the sensor, the sensor has a mounting groove or hole provided in the back plate. A sensor body fitted and attached to the sensor body, and a single conductive wire disposed inside the sensor body and forming a folded portion at the end thereof, and the folded portion is fixed at a wear limit position of the lining. A wear warning device for a lining, wherein a deformed portion formed integrally with the sensor main body is abutted so as not to rotate during running. The invention according to claim 2 is the lining wear warning device according to claim 1, wherein the lining fixed to the back plate is a non-split type, and the deformed portion is non-rotatably contacted with a side surface of the lining, A wear warning device for a lining, wherein a sensor body is attached to a mounting groove or a hole in a back plate. The invention according to claim 3 is the invention according to claim 1.
In the lining wear warning device according to the above, the lining fixed to the back plate is divided into a plurality, the deformed portion is inserted into the dividing groove formed between the linings so that it cannot rotate, and the sensor body is attached to the back plate. A lining wear warning device characterized by being attached to a mounting groove or hole. According to a fourth aspect of the present invention, there is provided the lining wear warning device according to any one of the first to third aspects, wherein the folded portion of the conductive wire protrudes from a front surface of the deformed portion. Device. The invention according to claim 5 is
The lining wear warning device according to any one of claims 1 to 3, wherein the bent portion of the conductive wire is embedded in the deformed portion. According to a sixth aspect of the present invention, in the lining wear warning device according to the fourth or fifth aspect, the folded portion of the conductive wire is substantially perpendicular to the sliding direction of the friction surface when viewed from the friction surface direction of the lining. A wear warning device for a lining, characterized in that it is arranged in the direction in which it wears. The invention according to claim 7 is the lining wear warning device according to any one of claims 1 to 6, wherein the sensor body is attached to the back plate using a clip.
A lining wear warning device.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

<A> Friction Pad FIG. 1 shows a back plate 11 of a friction pad 10 for a disc brake.
2 shows a state before and after the sensor 20 is attached, and FIG. 2 is a cross-sectional view of a main part after the sensor 20 is attached. On the surface of the back plate 11, a non-segmented lining 12 is integrally molded. Notch grooves 13 are formed at both ends of the back plate 11, and are slidably fitted to a disc brake carrier (not shown). Further, a mounting groove 14 having a length reaching the peripheral edge of the lining 12 is formed in a part of the back plate 11. The mounting groove 14 is a groove for mounting the sensor 20,
It is desirable that the mounting groove 14 is formed along the rotation direction R of the disk rotor, and the mounting groove 14 may be provided only on the rotor entrance side. On the back surface of the back plate 11, on both sides of the mounting groove 14, a concave portion 15 for engaging the spring clip 30 is formed.

<B> Sensor The sensor 20 includes a sensor main body 21 and a conductive wire 26 that is folded and inserted into the sensor main body 21. Sensor body 21
Is capable of abutting on the body 22 inserted into the mounting groove 14 of the back plate 11, the flange 23 disposed on the front side of the back plate 11, the back surface of the back plate 11 friction pad 10 and the side surface of the lining 12. A thermosetting non-conductive material integrally molded with the irregular shaped part 24,
For example, it is formed by blending various fillers such as glass fiber and inorganic filler based on a silicone resin. Deformed part 2
The shape of 4 is not limited to the illustrated block shape, and any other shape may be used as long as the shape can contact the side surface of the lining 12 and restrict the rotation of the sensor 20.

The sensor body 21 has two insertion holes 25 formed in the axial direction. One conductive wire 26 in which a conductive wire material is covered with an insulating coating is folded back and inserted into each insertion hole 25, and a conductive wire 26 projecting from the front surface of the deformed portion 24 is formed as a folded portion 27. The conductor 26 is fixed by heating the coating of the conductor 26 and fusing it to the sensor main body 21 or by bonding with an adhesive. The folded portion 27 can detect the wear limit of the ling 12 by breaking due to wear, and the wear limit position is set by the height of the deformed portion 24 from the mounting surface of the back plate 11.

<C> Spring clip 3 for attaching the sensor 20 to the friction pad 10
Numeral 0 denotes a leaf spring having a substantially U-shape. A pair of legs 32, 32 are formed on both sides of a U-shaped opening 31, and
The legs 32 are connected by a base 33. The pair of legs 32, 32 and the base 33 are warped in the thickness direction.

<D> Mounting Method of Sensor The mounting method of the sensor 20 by the spring clip 30 will be described.
And the side of the irregularly shaped portion 24 is lined with the lining 1.
2. Make contact with the side of 2. While fitting the opening 31 of the spring clip 30 into the body 22 of the sensor 20, the legs 32, 32
Is inserted between the flange 23 of the sensor 20 and the back plate 11 of the friction pad 10 while being bent, the sensor 20 is elastically supported by the back plate 11 by the spring force of the spring clip 30. The base portion 33 of the spring clip 30 is fitted into the concave portion 15 of the back plate 11 to prevent the spring clip 30 from coming out of the friction pad 10.

The folded portion 27 extends along a direction substantially perpendicular to the rotational direction R of the disk rotor (not shown), that is, a direction substantially perpendicular to the sliding direction of the friction surface when viewed from the friction surface direction of the lining 12. Once placed, the turn-back portion 27
If the wire breaks, it will be difficult for conduction to occur again.

[0013]

[Embodiment 2] Hereinafter, other embodiments will be described. The same parts as those in Embodiment 1 described above are denoted by the same reference numerals, and description thereof will be omitted.

FIGS. 3 to 5 show a large friction pad 1 for a disc brake mainly used for medium and large trucks.
Another embodiment applied to OA is shown.

Generally, the large-sized friction pad 10A is divided and fixed to the left and right sides of the back plate 11 in order to ensure uniformity of material distribution of the linings 12 and 12 and the workability, and a dividing groove is formed at the center of the linings 12 and 12. 16 are formed in the vertical direction. A mounting groove 14 is provided in the upper center of the back plate 11 along the dividing groove 16. The sensor 20 is installed by fitting its body 22 into the mounting groove 14 and inserting the deformed part 24 into the dividing groove 16 in a non-rotatable manner.

The sensor 20 is attached to the back plate 11 of the friction pad 10A using a substantially U-shaped spring clip 30A as shown. The basic configuration of the spring clip 30 </ b> A is the same as that of the above-described embodiment, except that the base 33 is bent into a U-shape to be sandwiched between the back plate 11, and that a pair of legs 32, Cut and raise a part of 32
a and 32a are formed. Each of the legs 32, 3
The two retaining pieces 32a, 32a are elastically engaged with the engaging holes 17, 17 formed in the back plate 11, and the spring clip 30A is formed.
Can be attached to the back plate 11.

Further, instead of the engaging holes 17, 17, a concave portion formed by coining or the like may be used.

[0018]

Third Embodiment FIGS. 6 and 7 show another embodiment in which the present invention is applied to a cast iron brake shoe 40 for a drum brake mainly used for medium and large trucks.

In the brake shoe 40, a curved back plate portion 42 is integrally formed on the outer end surface of a web 41 having an arc shape, and divided linings 43, 43 are formed on the outer surface of the back plate portion 42.
Are fixed with a plurality of rivets 44. And
A dividing groove 45 is formed between the runnings 43. At the center of the back plate portion 42, a mounting hole 46 into which the sensor 20B is inserted is formed. Body 2 of sensor 20B
Numeral 2 is designed to have a diameter capable of being inserted into the mounting hole 46, and the deformed portion 24 is formed so as to be hooked on the mounting hole 46. The sensor 20B is inserted into the mounting hole 46 of the back plate portion 42 from the lining 43 side, and a substantially U-shaped clip 30B is inserted into the annular groove 22a of the body portion 22 protruding from the back side of the back plate portion 42 via a spring washer 47. Fitted and fastened.

In the case of this embodiment, the irregularly shaped portion 24 of the sensor 20B abuts against the side surface of the dividing groove 45 to restrict the rotation.

Incidentally, the brake shoe 40 of this embodiment is a
Although the case where twin webs 41, 41 are provided on the back surface of 2 is shown, the web 41 may be single, or these may be made of steel plate.

[0022]

Fourth Embodiment In the sensors 20 and 20B described above, the case where the folded portion 27 is projected from the front surface of the deformed portion 24 has been described. However, the folded portion 27 is embedded in the deformed portion 24 as shown in FIG. You may make it. The wear limit position of the lining is electrically detected when the folded portion 27 is disconnected along with the wear of the deformed portion 24. The folded portion 27 of the conductor 26 may be a bare wire as shown, or may be covered. In the present embodiment, since the folded portion 27 is embedded in the sensor main body 21, it is suitable for a complicated transportation route or a vehicle traveling on a bad road, and has excellent durability and environmental resistance.

[0023]

As described above, the present invention has the following advantages. <B> A simple structure is achieved because the irregular part of the sensor body is brought into contact with the lining to prevent rotation, and the body is fitted into the mounting groove or hole provided on the back plate and fastened with a clip. Thus, the sensor can be securely attached while preventing the sensor from falling off and rotating, and the attaching operation is simple. <B> Complex processing and high processing accuracy are not required for the back plate and lining, and low cost can be dealt with. <C> Since the sensor mounting space is small, the sliding area (surface area) of the lining does not need to be reduced. <D> By making the folded part of the conductor project outside the sensor,
Positioning of the folded portion for detecting the wear limit position of the lining can be accurately and easily performed, and high detection accuracy can be secured.
Further, since the folded portion is easily worn, there is no possibility that the opposing disk rotor or brake drum is damaged. <E> By embedding the folded portion of the conductor in the sensor, it is suitable for vehicles having complicated transportation routes or for vehicles traveling on rough roads, and has excellent durability and environmental resistance. <F> If the folded portion of the conductive wire is arranged along a direction substantially perpendicular to the sliding direction of the friction surface when viewed from the direction of the friction surface of the lining, once the folded portion breaks, it is difficult for the conduction to occur again. .

[Brief description of the drawings]

FIG. 1 is an explanatory view according to Embodiment 1, and is a perspective view showing before and after assembly of a lining wear warning device;

FIG. 2 is a sectional view of a main part of a lining wear warning device after a sensor is attached.

FIG. 3 is an exploded perspective view of a lining wear warning device according to a second embodiment in which the lining is applied to a divided friction pad;

FIG. 4 is an exploded view of a part of the lining wear warning device as viewed from the lining side;

FIG. 5 is a sectional view of a main part of the lining wear warning device after the sensor is attached.

FIG. 6 is an explanatory diagram according to the third embodiment, and is a front view of a brake shoe.

7 is a sectional view taken along the line VII-VII in FIG.

FIG. 8 is an explanatory view according to the fourth embodiment, and is a partial cross-sectional view of another sensor in which a folded portion of a conductive wire is embedded.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10, 10A Friction pad 11 Back plate 12 Lining 13 Notch groove 14 Mounting groove 15 Depression 16 Division groove 17 Engagement hole 20, 20B Sensor 21 Sensor main body 22 Body 23 Flange 24 Deformed part 25 Insertion hole 26 Conductor 27 Folding part 30 , 30A Spring clip 30B Clip 31 Opening 32, 32 Leg 32a, 32a Hanging piece 33 Base 40 Brake shoe 41 Web 42 Back plate 43, 43 Lining 44 Rivet 45 Split groove 46 Mounting hole 47 Spring washer

Claims (7)

[Claims] 1. A wear warning device for a lining, wherein a sensor is attached to a part of the back plate, and the wear limit of the lining fixed to the back plate is electrically detected by the sensor, wherein the sensor is provided on the back plate. A sensor body fitted and attached to the mounting groove or hole, and a single conductive wire disposed in the sensor body and forming a folded portion at the end thereof, wherein the folded portion is formed of a lining. A lining wear warning device, wherein the lining wear warning device is fixed at a wear limit position, and a deformed portion formed integrally with the sensor main body is abutted so as to be unable to rotate during running. 2. The lining wear warning device according to claim 1, wherein the lining fixed to the back plate is a non-divided type, and the deformed portion is non-rotatably contacted with a side surface of the lining, and the sensor main body is fixed. A lining wear warning device, which is attached to a mounting groove or hole of a back plate. 3. The lining wear warning device according to claim 1, wherein the lining fixed to the back plate is divided into a plurality of portions, and the deformed portion cannot be rotated in the dividing groove formed between the linings. A wear warning device for a lining, wherein a sensor body is inserted into a mounting groove or a hole in a back plate. 4. The wear warning device for a lining according to claim 1, wherein the folded portion of the conductive wire protrudes from a front surface of the deformed portion. 5. The lining wear warning device according to claim 1, wherein the bent portion of the conductor is embedded in the deformed portion. 6. The lining wear warning device according to claim 4, wherein the folded portion of the conducting wire is substantially perpendicular to the sliding direction of the friction surface when viewed from the friction surface direction of the lining. A wear warning device for a lining, characterized in that it is oriented towards the lining. 7. The lining wear warning device according to claim 1, wherein the sensor main body is attached to the back plate by using a clip.