JPH043136Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Industrial Application Field) The present invention relates to a disc brake for a vehicle, particularly a disc that rotates together with a wheel, and a disc that is fixed to the vehicle on one side of the disc. a pair of friction pads arranged on both sides of the disk and each having a lining made of short metal fibers hardened with resin, and connected to the mounting via at least one pin parallel to the axis of the disk. It has an actuator that is supported slidably along the axis of the disk and presses one friction pad on one side of the disk against one side of the disk, and the reaction force of the actuator presses the other friction pad against the other side of the disk. a caliper, a rubber boot located between the mounting and the caliper to protect a sliding part between the pin and the mounting or the caliper, and a mounting for fixing to the end of the back plate of the friction pad. and a vibrating piece part that extends toward the side surface of the disk through the sides of the friction pad and the back plate, and that contacts the side surface of the disk at its tip and vibrates to generate an alarm sound when the lining of the friction pad is worn down to its service limit value; The present invention relates to a disc brake for a vehicle equipped with a friction pad wear warning member made of a plate material and having a spring acting portion that presses the vibrating piece portion against the end face on the back plate side with a predetermined force.

(Prior art) This type of disc brake is essentially
It is described in Publication No. 57-140934. In this device, the friction pad wear-out alarm member is attached only to one end of the back plate of the friction pad (disc insertion side end), and the friction pad wear-out alarm member consists of only the parts necessary to achieve the alarm function. has been done.

(Problems to be solved by the invention) In recent years, so-called semi-metallic type linings made of short metal fibers hardened with resin have come into widespread use for friction pad linings. When we conducted a durability test using this friction pad with semi-metallic type lining on the above-mentioned known disc brake, we found that under severe brake usage conditions,
Sparks generated by the friction between the disk and the lining containing short metal fibers ignited the vaporized resin due to the high heat, creating a flame. The flame appeared in areas with good air supply, ie, on the radially inner side of the disk of the friction pad. Then, the flame that appears on the inside of the friction pad in the radial direction of the disk is carried by the airflow and heads towards the rubber boot (which protects the sliding part between the pin and the caliper or mounting), and the boot is burnt out by the flame. Worry arose.

In order to eliminate this concern, it is conceivable to provide a fireproof wall member that protects the boots from flames. However, providing a dedicated firewall member increases the cost significantly, so there is room for consideration.

Therefore, an object of the present invention is to eliminate the fear of boot burnout caused by the flames without using a dedicated firewall member.

[Structure of the idea]

(Means for Solving the Problems) In order to achieve the above object, the present invention attaches the friction pad wear warning members to both ends of the back plate of the friction pad located on the same side as the boot with respect to the disk, and Each friction pad abrasion warning member is integrally formed with a fire prevention wall portion that blocks flames generated on the inside of the friction pad in the radial direction of the disk and directed toward the boot from reaching the boot.

(Function) According to this configuration, the unit price of the friction pad abrasion alarm member is almost the same as the conventional one, and is cheaper than the unit price of a dedicated fire protection member due to the cost reduction effect of mass production. It is smaller than the case where wall members are used.

(Example) Hereinafter, the present invention will be further clarified by describing an example of the present invention based on the drawings.

1 to 6, a disc brake 10 has a mounting 12 fixed to a non-rotating part of the vehicle such as a knuckle (not shown) inside a disc 11 that rotates together with a wheel (not shown).
This mounting 12 has a pair of arms 12A, 12B extending from the inside of the disk through the outer periphery of the disk to the outside of the disk. Friction pads 13 are held at both ends in the circumferential direction of the disk and in the radial direction of the disk.
14 is slidably supported in the disk axial direction.

When the disc brake 10 is attached to a vehicle, the diagonally upper left side of FIG. 1 is the upper side of the vehicle.
If the vehicle is moving forward, disk 11
rotates in the direction of arrow R, and the linings 13B, 14B of the friction pads 13, 14
is a so-called semi-metallic type.

A caliper 15 for pressing the friction pads 13, 14 against the side surface of the disk has a hydraulically actuated piston 16 that presses the back plate 13A of the friction pad 13 toward the inside surface of the disk, and a cylinder 17 that accommodates the piston 16. . This cylinder 17 constitutes an actuator with the piston 16, and has a bridge portion 17A located on the outer circumferential side of the disk, a reaction portion 17B located on the outer side of the disk, and a pair of bridge portions 17B located on the outer side of the disk, which protrude in the circumferential direction of the disk. It has boss portions 17C and 17D.

Boss portion 17 of cylinder portion 17 of caliper 15
Hollow pins 18A and 18B that slidably pass through C and 17D are attached to the mounting 12 by bolts 19A and 19B that are located inside the pins and are screwed into the arms 12A and 12B of the mounting 12.
The caliper 15 is supported by these pins 18A, 18B so as to be slidable in the disk axial direction with respect to the mounting 12.

Rubber boots 21A, 21B, 22A, 22B are provided between both ends of the pins 18A, 18B and both ends of the bosses 17C, 17D of the cylinder 17 to protect the sliding parts of the pins and the bosses from infiltration of muddy water, etc. It is being

Linings 13B, 1 of friction pads 13, 14
In order to warn that 4B has worn down to its service limit, friction pad wear alarm members 23 and 24 are attached to the side ends of the back plates 13A and 14A on the disk insertion side (right end in Figure 2), respectively. ing. As shown in detail in FIGS. 7 to 11, the friction pad abrasion alarm member 23 is formed using a plate material having spring properties, and is formed from a side end protrusion 13 of the back plate 13A.
From the side edge of the part of the mounting part 23a bent in a U-shape that is assembled and grasped from below in FIG.
Fire wall portion 23 extending away from the back surface of the back plate
b, a loop-shaped spring acting part 23c extending from this fireproof wall part 23b, and a vibration extending from this spring acting part 23c toward the inner surface of the disk through the gap between the back plate side end and the arm 12B. It has a piece portion 23d. The spring acting part 23c presses the hemispherical convex part 23e formed on the vibrating piece part 23d against the back plate side end surface with a predetermined force, and the lining 13B reaches the limit value L (the first
When the vibrating piece 23d comes into contact with the inner surface of the disk and vibrates, it vibrates stably using the convex part 23e as a fulcrum and generates a clear beeping sound. The friction pad wear warning member 24 also consists of the same parts as the friction pad wear warning member 23, but because it is placed outside the disk, it has a shape that is symmetrical to the friction pad wear warning member 23 in FIG. It is.

Boots caused by severe brake use 2
In order to protect the boot 21A from flames directed towards the boot 21A, a friction pad abrasion warning member 24 is attached to the disk retraction side end (the left end in FIG. 2) of the back plate 13A of the friction pad 13.

As brake fluid pressure is supplied to the hydraulic pressure chamber 20 formed by the piston 16 and the cylinder 17, the piston 16 presses the friction pad 13 against the inner surface of the disc 11, and the reaction force of the operation causes the cylinder 17 to The reaction portion 17B presses the friction pad 14 against the outer surface of the disk, producing a braking action. In this braking action, the braking torque applied to the friction pads 13, 14 is directly transmitted from the back plates 13A, 14A to the arms 12A, 12B.
transmitted to.

Friction pad 1 due to repeated braking action
When the linings 13B and 14B of No. 3 and 14 are worn down to the service limit value L, the vibrating pieces 23d and 24d of the friction pad wear warning members 23 and 24 (attached to the friction pad 14) come into contact with the side surface of the disk. It vibrates and emits an alarm sound.

Furthermore, even if a flame is generated due to the severe braking action and heads towards the boot 21A, it will be intercepted by the fire prevention wall 24b of the friction pad abrasion warning member 24 attached to the friction pad 13,
Since A is not exposed to flame, the boot 21A is prevented from burning out. Severe braking action normally occurs when the vehicle moves forward, but even if it occurs when the vehicle backs up and flames are generated and head towards the boot 21B, the fireproof wall portion 23 of the friction pad abrasion warning member 23 will be damaged on the way.
b, thereby preventing the boot 21B from burning out.

In the embodiment described above, a pair of pins 1 for supporting the caliper 15 with respect to the mounting 12 are used.
8A and 18B are arms 12 of mounting 12
A and 12B, but it is possible to fix these pins to the caliper 15 and slide with the mounting 15, as is well known (for example, see Japanese Utility Model Application Publication No. 56-2431).

In addition, the above-mentioned embodiment and the one described in Japanese Utility Model Application Publication No. 56-2431 are for relatively lightweight vehicles, and the caliper weight is not very large, so the pins 18A, 1
8B is supported in a cantilevered manner, and therefore, only a friction pad wear-out alarm member 24 that acts as an alarm is attached to the friction pad 14 on the outside of the disk. On the other hand, in the case of heavy vehicle use, well-known
58-61934), the caliper is supported by mountings on both sides of the disk via pins, and there are boots on the outside of the disk that are at risk of being burned out by the flames.
By attaching friction pad wear warning members 23 and 24 to both ends of the friction pads located outside the disk, it is possible to prevent these boots from burning out.

Furthermore, the pins that slidably support the caliper with respect to the mounting do not need to be a pair separated in the circumferential direction of the disk.
As shown in Japanese Patent No. 132920, it is also possible to use only one pin (only pin 18A in FIG. 1).

The means for pressing the friction pads against the disk is not limited to a hydraulically operated piston-cylinder, but may be modified as appropriate.

[Effect of idea]

As described above in detail, according to the present invention, it is possible to construct a disc brake for a vehicle with a friction pad wear-out warning member that is free from the fear of boot burnout and has a small increase in cost.

[Brief explanation of the drawing]

Figure 1 is a view of an embodiment of the present invention as seen from inside the vehicle, Figure 2 is a view seen from above Figure 1, Figure 3 is a view seen from the left side of Figure 1, and Figure 4. is a sectional view taken along the - line in FIG. 1, FIG. 5 is a diagram showing the shape of the mounting in FIG. 1, FIG. 6 is a diagram showing the shape of the friction pad in FIG. 1, and FIG. is a view showing the friction pad wear warning member in Fig. 1, Fig. 8 is a view seen from the left side of Fig. 7, Fig. 9 is a view seen from the bottom of Fig. 7, and Fig. 10 is a view shown from the bottom of Fig. 7. 8 is a sectional view taken along the - line in FIG. 8, and FIG. 11 is an enlarged sectional view taken along the - line in FIG. 1. Explanation of symbols, 11... Disc, 12... Mounting, 13, 14... Friction pad, 13
A, 14A... Back plate, 13B, 14B... Lining, 15... Caliper, 16... Piston, 1
7...Cylinder, 18A, 18B...Pin, 21
A, 21B, 22A, 22B...Boots, 23,
24...Friction pad wear warning member, 23a, 24
a... Mounting part, 23b, 24b... Fire wall part,
23c, 24c... Spring acting part, 23d, 24d
...The vibrating piece.

Claims (1)

[Scope of utility model registration request] A disc that rotates together with the wheel, a mounting that is fixed to the vehicle on one side of the disc, and a pair of friction pads that are arranged on both sides of the disc and each have a lining made of short metal fibers or the like hardened with resin. an actuator that is slidably supported by the mounting through at least one pin parallel to the axis of the disk along the axis of the disk, and that presses one friction pad on one side of the disk against one side of the disk; a caliper which presses the other friction pad against the other side of the disk by the reaction force of the actuator; and a caliper located between the mounting and the caliper to protect the sliding portion between the pin and the mounting or the caliper. The rubber boot, the attachment part for fixing the friction pad to the side end of the back plate, and the lining of the friction pad extending toward the side of the disk through the side of the back plate have been worn down to the service limit. A friction pad wear-out alarm member made of a plate material, which has a vibrating piece that contacts the side surface of the disk at the tip and vibrates to generate an alarm sound, and a spring acting part that presses this vibrating piece against the end face of the back plate with a predetermined force. In the disc brake for a vehicle equipped with a friction pad wear warning member, the friction pad wear warning member is attached to both ends of the back plate of the friction pad located on the same side as the boot with respect to the disc, and each The friction pad wear-out warning member is integrally formed with a fire prevention wall part that blocks flames generated on the inside of the friction pad in the radial direction of the disk and directed toward the boot from reaching the boot during braking.