JPH0223877Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a friction pad for a disc brake, and in particular, an electric wear detection sensor whose disconnection part is disconnected when the friction material wears to the wear limit. Regarding the friction pads provided.

[Prior art]

In general, friction pads for disc brakes are attached to a back metal that is attached to the brake, and are fixed to the surface of the back metal using adhesives, pressure molding, or other means, and are able to frictionally engage with the disc that rotates with the wheel. It is composed of a friction material that wears out while applying braking. When the wear amount of the friction material reaches the wear limit, it is necessary to replace it with a new friction material, so the friction pad is equipped with a wear alarm device to warn that the friction material has worn down to the wear limit. ing.

In addition to using a metal abrasion alarm piece, this type of wear alarm device has a lead wire bent to form a broken part, and an insertion part for inserting a backing metal into the lead wire with the broken part protruding. A sensor using an electric wear detection sensor is known.

According to the prior art, as a method of attaching the above-mentioned wear detection sensor to the friction pad, an insertion hole is provided in the backing plate that penetrates from the back side to the front side, and the broken part of the lead wire is placed on the wear limit surface of the friction material. Insert the insertion part into the insertion hole so that it reaches the end, and secure it with adhesive.

[Problem that the invention attempts to solve]

Therefore, in the conventional technology that uses adhesive to fix the wear detection sensor to the back metal, the gap between the insertion hole and the insertion part can be sealed with adhesive, and rainwater etc. can not enter into the broken part of the lead wire. However, the temperature of the friction pad reaches several hundred degrees due to the frictional heat generated during braking, and this high heat deteriorates the adhesive strength of the adhesive, causing the wear detection sensor to fail. The drawback is that it can fall out from the insertion hole of the back metal.

[Means for Solving the Problems] The means of the present invention configured to solve the above-mentioned problems consists of a backing plate having a friction material attached to its surface, and at least one of the front and back surfaces of the backing metal. a wear detection sensor located near the locking portion and inserted from the back side of the back metal to the front side with the disconnection portion protruding to the wear limit surface of the friction material; a front-side clamping part comprising a fixing member for fixing the wear detection sensor to the backing metal, the fixing member abuts the front and back surfaces of the backing metal, and one of the fixing members has an engaging part that engages with the locking part; and a back side clamping part, a sensor pressing part that is integrally formed on the back side clamping part and presses the wear detection sensor against the back metal, a connecting part that connects the front side clamping part and the back side clamping part, and the connecting part. and a pair of spring parts formed on both end sides of the metal backing plate and abutting against the circumferential surface of the backing metal.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

In the figure, 1 is a friction pad for a disc brake, 2 is a thick plate-shaped back metal that constitutes the friction pad 1, and the left and right ends of the back metal 2 are provided with support for a brake moving mechanism (not shown). An upper protruding piece 3A and a lower protruding piece 3B are formed.

4, 4 are located near each lower protrusion 3B, and the back plate 2
By driving a punch into the surface 2A of the
The punch holes formed in the surface 2A to form each of the protruding locking parts 4 are concave locking parts 5. And secret money 2
An insertion hole 6 for inserting a wear detection sensor 9, which will be described later, is formed from the front surface 2A to the back surface 2B of the back metal 2 to the side of the protruding locking portion 4 located on one end side. has been done.

Reference numeral 7 denotes a friction material which is formed under pressure on the surface 2A of the backing metal 2 by a molding method and wears out while providing braking by frictionally engaging with the disk.The friction material 7 covers almost the entire surface of the surface 2A. However, the friction material 7 is not fixed around each concave locking portion 5. Further, a concave portion 8 with a bottom is formed in the friction material 7 concentrically with the insertion hole 6, and a bottom surface 8A of the concave portion 8 is aligned with the wear limit surface 7A of the friction material 7. It is formed.

Reference numeral 9 denotes an electric type wear detection sensor used in this embodiment. The wear detection sensor 9 is bent in the middle into a substantially U-shape to form a disconnection part 10A which is disconnected when it comes into contact with a disk, and both ends are connected to a socket 11. It consists of a lead wire 10, a cylindrical insertion part 12A that is inserted into the insertion hole 6 of the back metal 2, and a flange part 12B that comes into contact with the back surface 2A of the back metal 2, and the insertion part 12A
and an insertion plug body 12 made of a synthetic resin material or the like that is fixed to the intermediate side of the lead wire 10 with the disconnection part 10A exposed from the distal end surface of the lead wire 10.

Next, reference numeral 13 indicates a fixing member for fixing the abrasion detection sensor 9 to the back metal 2. Reference numeral 14 denotes a front side clamping part which constitutes the fixing member 13 and comes into contact with the surface 2A side of the back metal 2. The front side clamping part 14 is a front side contact piece which curves inward in a convex shape and comes into contact with the surface 2A of the back metal 2. 14A, and a locking piece that is formed in a narrow tongue shape and protrudes from the upper end of the front side contact piece 14A, and is bent inwardly in a curved shape so as to fit into and engage with the concave locking portion 5 of the back metal 2. It consists of 14B. Reference numeral 15 denotes a back side clamping part that faces the front side clamping part 14 and comes into contact with the front surface 2A side of the back metal 2. The back side clamping part 15 has a rectangular shape with a vertical width and a width wider than the front side clamping part 14. A fitting hole 15A that fits into the protruding locking portion 4 of the back metal 2 is formed in the center. Reference numerals 16 and 16 designate a pair of upper and lower sensor pressing parts for pressing the insertion plug 12 inserted into the insertion hole 6 of the backing metal 2 against the backing metal 2, and each of the sensor pressing parts 16 is curved to provide spring properties. It is formed in a strip shape to protrude laterally from the back side holding part 15 via the part 16A, and a notch formed in the shape of a long groove between the sensor pressing parts 16, 16 becomes a lead wire insertion part 17.

Further, reference numeral 18 denotes a connecting part that connects the front side clamping part 14 and the back side clamping part 15 in a substantially L-shape, and the connecting part 1
On one side of 8, there is a one-side spring part 19 which protrudes like a tongue in the same direction as the sensor pressing part 16, and whose base part is bent slightly upward so that it comes into pressure contact with the circumferential surface 2C of the back metal 2. is formed. Further, on the other side of the connecting portion 18, a pair of notches 18A, 18A parallel to the back side clamping portion 15 form the other side spring portion 20, which has the same shape as the one side spring portion 19, and the other side spring portion 20 has the same shape as the one side spring portion 19. The base portion of the portion 20 is also bent slightly upward so that it comes into pressure contact with the circumferential surface 2C of the back metal 2.

Thus, the fixing member 13 in this embodiment is
Front-side clamping part 14, back-side clamping part 15, fitting hole 15A formed in the back-side clamping part 15, back-side clamping part 15
A pair of sensor pressing parts 16 integrally formed with
16, a lead wire insertion part 17 formed between the sensor pressing parts 16, 16, a connecting part 18 connecting the front side clamping part 14 and the back side clamping part 15, and a pair of spring parts formed on both sides of the connecting part 18. 19 and 20, and the fixing member 13 is formed by bending a plate material so that the entire fixing member 13 has spring properties.

The friction pad with a wear detection sensor according to this embodiment is constructed as described above, and the assembly order will be described next.

First, apply adhesive to the insertion plug 12 of the wear detection sensor 9 and insert it into the insertion hole 6 from the back side 2B side of the backing metal 2, so that the disconnected part 10A of the sensor 9 touches the friction limit surface 7A of the friction material 7. The insertion plug 12 is fixed to the backing metal 2 in a state where it faces into the recessed part 8 so as to reach the inside of the recessed part 8. Next, the front side clamping part 14 and the back side clamping part 15 of the fixing member 13 are pushed open so as to be separated and fitted into the back metal 2, and while the lead wire 10 is inserted into the lead wire insertion part 17, each sensor pressing part 16 is brought into contact with the flange portion 12B of the insertion plug 12 protruding from the back surface 2B of the back metal 2. And the spring parts 1 on both sides
9 and 20 against the circumferential surface 2C of the backing metal 2, and further fitting the fixing member 13 to the backing metal 2 against the spring force of the respective spring parts 19 and 20.
The wear detection sensor 9 is bonded to the friction pad 1 by engaging the locking piece 14B with the concave locking part 5 and fitting the fitting hole 15A of the rear side holding part 15 into the protruding locking part 4. The fixing agent and the fixing member 13 ensure the fixation.

According to the present embodiment described above, the fixing member 13 for fixing the insertion plug 12 of the wear detection sensor 9 to the back metal 2 is provided on the back side clamping part 15, and the protruding locking part 4 of the back metal 2 is provided. a fitting hole 15A that engages with the
As shown in FIG. 12, the pair of left and right spring portions 19 and 20 press against the circumferential surface 2C of the backing metal 2, so that the backing metal is held at three points, A, B, and C, as shown in FIG. 2 is supported. Further, on the surface 2A side of the back metal 2, the pair of spring parts 19 and 20,
It is supported at three points in the same manner as the back surface 2B by the locking pieces 14B of the front side clamping part 14 that are engaged with the concave locking part 5. As a result, the fixing member 13 can be stably engaged with the backing metal 2, so the 13th
As shown in the figure, accidents such as the fixing member 13 rotating and coming off the back metal 2 or the sensor pressing portions 16 cutting the lead wires 10 during the rotation can be reliably prevented.

Further, in the fixing member 13 according to this embodiment, the front side clamping part 14 is engaged with the concave locking part 5 of the back metal 2 by utilizing its spring property, and the back side clamping part 15 is engaged with the protruding locking part 4. With this structure, it can be easily and reliably fixed to the back metal 2 without using any special assembly jig or the like.

Furthermore, since the upper end side of the front side clamping part 14 of the fixing member 13 according to this embodiment is formed into a narrow tongue-like locking piece 14B, the caulking part for caulking the conventional metal wear alarm piece can be formed using a punch. A punch hole formed on the surface 2A of the back metal 2 to form a protrusion can be used as the concave locking portion 5. As a result, the back metal plate 2 according to the present embodiment can also be used as is, even a conventional metal plate type abrasion warning piece crimped onto the back metal plate, and the usability of the back metal plate 2 can be improved.

In this embodiment, a concave locking portion 5 is provided on the surface 2A of the backing metal 2, and a locking piece 14B that fits into and engages with the concave locking portion 5 is formed on the front side holding portion 14 of the fixing member 13. , a protruding locking portion 4 is formed protrudingly on the back surface 2B of the back metal 2, and a fitting hole 15 that engages with the locking portion 4 is formed on the back side clamping portion 15 of the fixing member 13.
Although it has been described that A is provided, contrary to the above-mentioned configuration, a protruding locking portion is formed on the surface 2A of the back metal 2,
A concave locking portion may be formed on the back surface 2B. Furthermore, a through hole may be formed in the backing plate to form concave locking portions on both the front and back sides,
The fixing member may be fixed by forming a concave locking portion or a protruding locking portion only on either the front surface or the back surface.In short, the fixing member 13 can be supported with respect to the back metal 2 at three points. Any configuration is fine.

Further, the friction pad 1 described in the embodiment is taken as an example for use with a left brake caliper, and the insertion hole 6 for the wear detection sensor 9 is also described as being located on the left end side in FIG. 1 and formed in the back metal 2. However, friction pad 1
If it is for the right brake caliper, the corresponding insertion hole 6
may be formed at the right end side in FIG.

[Effect of idea]

According to the present invention configured as detailed above,
The wear detection sensor is fixed to the back metal with an adhesive and also fixed to the back metal with a fixing member, so even if the adhesive strength of the adhesive deteriorates due to frictional heat during braking, the wear detection sensor will not fall off from the back metal. Accidents can be reliably prevented and the reliability of friction pads equipped with wear detection sensors can be significantly improved.

[Brief explanation of the drawing]

Fig. 1 is an external view of a friction pad according to an embodiment of the present invention seen from the back side, Fig. 2 is a partially cutaway plan view of the friction pad, and Fig. 3 is an electric wear detection sensor used in this embodiment. 4 is a front view of the fixing member according to the embodiment, FIG. 5 is a right side view of the fixing member, FIG. 6 is a plan view of the fixing member, and FIG. 7 is a wear detection on the friction pad. FIG. 8 is a plan view of FIG. 7, FIG. 9 is an enlarged sectional view in the direction of the - arrow in FIG. 7, and FIG. 11 is a view in the direction of arrow B in FIG. 9, FIG. 12 is an explanatory diagram showing the state of engagement of the fixing member with the back metal, and FIG. 13 is an enlarged cross-sectional view in the direction of arrow B in FIG. FIG. 7 is a state explanatory diagram illustrating the reason why it is possible to prevent the sensor pressing portion of the fixing member from cutting the lead wire. 2...back metal, 2A...front, 2B...back, 7
... Friction material, 4 ... Protruding locking part, 9 ... Wear detection sensor, 10A ... Disconnection part, 13 ... Fixing member,
14... Front side clamping part, 15... Back side clamping part, 15
A... Fitting hole (engaging part), 16... Sensor pressing part,
18... Connection portion, 19, 20... Spring portion.

Claims (1)

[Scope of utility model registration request] A backing metal with a friction material attached to its surface, a locking part provided on at least one of the front or back side of the backing metal, and a disconnection part located near the locking part to the wear limit of the friction material. The wear detection sensor is inserted from the back side of the back metal to the front side so as to protrude up to the surface, and a fixing member fixes the wear detection sensor to the back metal, the fixing member abutting the front and back sides of the back metal, A front side clamping part and a back side clamping part each having an engaging part that engages with the locking part, and a sensor that is integrally formed in the backside clamping part and that presses the wear detection sensor against the back metal. A wear detection sensor comprising a pressing part, a connecting part connecting the front side clamping part and the back side clamping part, and a pair of spring parts formed on both ends of the connecting part and abutting against the circumferential surface of the back metal. Comes with friction pads.