JPH0127286B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a disc brake used for braking an automobile, and an object of the present invention is to provide a disc brake that prevents noise (so-called squeal) generated during braking and does not cause discomfort to passengers. purpose.

As shown in Figure 1, a disc brake has a support 2 that sandwiches a rotor 1 that rotates with the wheels.
A pair of pads 3 are attached to the rotor 1 so as to be slidable in the front and back directions (rotor axial direction), and a caliper 4 is attached to the top of the support 2 so as to be slidable in the front and back directions with respect to the support 2. It is composed of
When braking, when one pad is pressed against one side of the rotor 1 by the piston installed in the caliper 4, the caliper 4 slides a little against the support 2 as a reaction, and the other pad 3 is also pressed against the caliper claw. 4a to the other surface of the rotor 1, strongly clamping the rotor 1 from both sides and performing braking by frictional force.

However, disc brakes constructed and operated in this manner often generate a noise called squeal during braking, which causes discomfort to passengers, pedestrians, and the like.

The causes of such noise are thought to be as follows. In other words, the rotor 1 of the disc brake does not rotate completely flat, but rotates in a manner that swings slightly from side to side (in the rotor axis direction), so the surface that contacts the lining of the pad 3 on the side of the rotor is As it rotates, it becomes as if there are unevenness. Therefore, during braking, the pad 3 that comes into contact with the side surface of the rotor oscillates a little according to the unevenness, and this oscillation generates a noise called squeal. Various mechanisms can be considered to generate noise due to rocking, but for example, if the pad 3 is
When the pad 3 swings in the direction of rotation), as shown in FIG. When the pad 3 begins to fall down, the end surface 5a of the lining 5 of the pad 3 on the side opposite to the anchor bites into the side surface of the rotor 1, and the rotor side surfaces strongly rub against each other, causing noise due to collision sounds and friction sounds.
In addition, when the pad 3 swings in the width direction as shown in FIGS. 3 and 4, there is a collision sound between the corner of the lining 5 and the side surface of the rotor 1, or a friction sound between the support 2 and the back metal of the pad 3. It is thought that mixed noise will be generated.

The present invention provides a disc brake that effectively prevents the generation of noise by suppressing the movement of the pad 3 in the axial direction of the rotor to prevent the pad 3 from swinging, which causes noise as described above. .

The present invention will be explained below with reference to drawings showing examples.

The disc brake of the present invention uses an adhesive, as shown in FIG. 5a (when the adhesive is applied to both sides of the woven fabric) and FIG. The pad 3 is characterized in that an adhesive shim 9 made by applying 7 on both sides or one side of a woven fabric 8 is attached to the back side of the back metal 6 of the pad 3. Reference numeral 10 denotes a release paper that is attached to the surface of the adhesive 7 and peeled off when it is attached to the back metal 6.

Prior to attaching the pad 3 to the support 2, the adhesive shim 9 as described above is attached to the back side of the back metal 6 of the pad 3, excluding the inner release paper 10 (on the side to be pasted to the pad). After pasting this pad 3
is attached to the support 2 as shown in FIG.

Attach the adhesive shim to the support 2 as shown in Figure 6.
0 is pasted, remove it as well) When you brake after assembling the disc brake, the piston 11
and the inner surface of the caliper pawl 4a (these surfaces will be referred to as working surfaces in this specification) are each strongly pressed against the back metal 6 of the pad via the adhesive shim 9. For this reason, the adhesive 7 applied to the outer surface of the adhesive shim 9 (in the case of double-sided application) and the adhesive 7 leaked from the grains of the woven fabric 8 (in the case of single-sided application) are deposited on the pad as shown in FIG. 3, the back metal 6 and caliper claws 4a, 4a, or the back metal 6 and the piston 1
1 and stick together. Whether the adhesive 7 is applied to both sides of the woven fabric 8 or to one side, the adhesive 7
is attached to the fibers of the woven fabric 8 or enters into the minute space between the weaves of the woven fabric and is held within this space, and gently connects the backing metal and the working surface of the pad as described below. It becomes like this. If the adhesive is applied to both sides of the woven fabric, the adhesive can quickly penetrate into the weave.

In this way, attach the pad 3 to the caliper claws 4a, 4a,
Since the pad 3 is made to adhere to the piston 11, during braking, the pad 3 adheres to the working surface via the adhesive shim 9, and even if the rotor rotates while wobbling in its axial direction, it is suppressed from swinging together with the rotor. Due to this rocking, the pad moves away from the action surface and moves in the rotor axial direction, and as shown in Figures 2 to 4, the opposite side of the pad 3 from the anchor is prevented from strongly digging into the rotor or strongly rubbing against it, thus preventing the braking. Occasional squealing is prevented from occurring.

The adhesive 7 connects the piston and caliper pawl to the pad gently, and the adhesive can move a minute amount while being restrained by the woven fabric, so the minute movement of the adhesive causes the pad to come into contact with the piston and caliper pawl. Automatic adjustment is performed to ensure equality.
Furthermore, as mentioned above, since the adhesive is held by the spaces and fibers within the woven fabric 8, the adhesive shim 9 is removed during braking.
Even if the woven fabric is compressed by strong pressure between the backing metal of the pad and the working surface of the caliper claw, there will still be spaces in the woven fabric, albeit smaller, and the adhesive will be absorbed into these spaces. Therefore, even after the brake is released, the pad backing plate and the working surface are sufficiently adhered by the adhesive.

A small amount of adhesive extruded from between the back metal and the working surface forms a small bulge that adheres to the edge of the piston 11 and the caliper pawl, as shown in Figure 7, and serves to bond the back metal and the caliper pawl. There is. Therefore, when the brake is released, the piston and the like move away from the rotor together with the pads, so that it is possible to prevent the rotor from coming into contact with the pads even after the brake is released, which is called dragging.

Further, due to the elastic action and vibration damping action of the adhesive shim itself, it is possible to prevent noise caused by vibrations of the pad 3 or the caliper pawls 4a, 4a, etc. during braking. For this purpose, the thicker the adhesive shim 9 is, the more effective it is, but in view of various circumstances, it is practically desirable to set the thickness to about 0.2 to 1 m/m.

The woven fabrics used in the present invention include those made from polyester, polyimide, glass, etc.
These can be impregnated with epoxy resin to improve heat resistance.

As the adhesive, a pressure-sensitive adhesive that is semi-crosslinked (that is, semi-cured) and is not completely cured but can hold the pad can be used. This includes rubber-based, acrylic-based, silicone-based, and other resins.

This woven fabric uses the adhesion force between the adhesive and the fibers of the woven fabric and the penetration of the adhesive into the spaces between the weaves of the woven fabric, so that the adhesive always stays in contact with the working surface of the piston etc. and the back metal. It acts to hold the adhesive as it exists in the. Without the woven fabric, each time you brake, the adhesive would be pushed out sideways little by little from between the backing metal and the working surface, and at this time, the pad and the working surface would repeatedly shift minutely laterally, so the adhesive would gradually move away from the working surface. As a result, the adhesive is no longer present between the back metal and the working surface, and the desired adhesive effect cannot be obtained. In this invention, adhesive shims with adhesive applied to woven fabric are used, so
The adhesive will not be pushed out sideways from the working surface and the adhesive will not deteriorate.

Additionally, a special applicator is required to apply adhesive directly to the backing of the pad, but with this invention, the adhesive is applied to the woven fabric in advance, so there is no need to apply adhesive directly to the pad. Adhesive shims coated with adhesive and lined with release paper are commercially available as repair products, and can be used at repair shops to attach to pads when brake noise occurs. In addition, if the woven fabric is coated with an adhesive and a release paper is attached, it can be handled without becoming sticky, making it easier to attach it to the back metal and handle it as a repair item. The adhesive may be applied to only one side of the woven fabric, but if it is applied to both sides and release paper is pasted on both sides, it is easier to handle and the adhesive between the working surface and the back metal can be established quickly. effective.

In addition, a squeal prevention device in which an elastic shim board made of woven glass fiber impregnated with a heat-resistant rubber adhesive is placed on the back metal of the pad is proposed in Utility Model Application No. 107284 (1983).
No. 24548), the rubber adhesive used for this hardens into a solid rubber, and the glass fiber woven fabric incorporated into it supports the pressure applied during braking. This method is different from the present invention in that it prevents the hardened adhesive from being excessively compressed, and when the brake is released, the elasticity of the hardened adhesive avoids the dragging phenomenon.

As described above, the present invention interposes an adhesive shim coated with an adhesive on both or one side of a woven fabric between the back surface of the pad and the working surface that presses the pad,
Since the swinging of the pads during braking is restricted, it is possible to effectively prevent the occurrence of squealing due to the swinging of the pads.

[Brief explanation of drawings]

FIG. 1 is a front view showing an example of a disc brake in which the present invention is implemented, FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1 showing the longitudinal movement of the pad, and FIGS. Fig. 3 is a sectional view similar to Fig. 2, Fig. 4 is a BB sectional view of Fig. 3,
Figures 5 to 7 show examples of the present invention; Figure 5a is a perspective view of a shim and pad with adhesive applied to both sides of the woven fabric before being attached; Figure 5b is a perspective view of the pad before adhesive is applied. Similar perspective views when only one side is used, Figures 6 and 7 show the assembled state of the pad coated with adhesive shims, Figure 6 shows the pad immediately after assembly, and Figure 7 shows the state after braking, respectively. It is an AA sectional view of the figure. 1: Rotor, 2: Support, 3: Padded, 4:
Caliper, 4a: Nail, 5: Lining, 6: Back metal, 7: Adhesive, 8: Woven fabric, 9: Adhesive shim, 1
0: release paper, 11: piston.

Claims (1)

[Claims] 1 A pair of pads 3 that are slidably held on a support 2 are attached to a caliper 4 that is engaged with this support 2.
In a disc brake that performs braking by pressing the side surface of the rotor 1 that rotates together with the wheel, using a piston 11 and a caliper pawl 4a that are fitted into the disc brake,
A pressure-sensitive adhesive 7 that does not harden is placed on at least one side of the woven fabric 8 between at least one of the working surfaces of the piston and caliper claw that presses the pad 3 against the side surface of the rotor 1 and the back surface of the back metal 6 of the pad 3. A disc brake characterized by interposing an adhesive shim 9 formed by coating.