JPS5848425Y2 - Insulation device for vehicle disc brake pistons - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in disc brake pistons for vehicles.

FIG. 1 shows an overview of a single-piston flowing caliper type as an example of a conventional vehicle disc brake.

The caliper 8 straddles the rotor 6 that rotates with the wheel.
Only one side has a piston 3, and between the piston 3 and rotor 6 there is a friction material 1 reinforced with a backing plate, and the other side also has a friction material 1 and a backing plate supported by a caliper 8. .

When the brake pedal is depressed, the hydraulic pressure in the mask cylinder is guided to the hydraulic chamber of the caliper, and as the pressure of the brake fluid 4 increases, the piston 3 presses the friction material against the rotor 6. Further, due to the increase in hydraulic pressure, the caliper 8 moves and pushes the outer friction material. The rotor 6 is pressed against the rotor 6 from both sides.

However, in the conventional devices as described above, there is no means for blocking the transmission of heat generated by the friction material to the piston between the piston and the backing plate.

The purpose of the present invention is to focus on the above points, and to
To provide a piston insulation device capable of blocking the heat generated between the pistons and preventing the formation of paper in the brake fluid 4,
Its feature is that a heat insulating material is attached to the piston end surface that forms the contact surface with the backing plate via a damping material on the same end surface side.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows an embodiment of a piston according to the present invention.

In the figure, a stepped portion is formed on the inner circumference side of the end surface of the piston 3 on the backing plate side, and a heat insulating material 5 with a flange-like cross section and a damping material (copper plate or rubber) on the piston end surface side are formed.
7 is inserted and fixed.

FIG. 3 shows another embodiment of the invention, in which the piston 3'
A groove is formed on the end surface of the groove, a damping material (copper plate or rubber) γ' is inserted into the bottom of the groove, and a heat insulating material 5 with a T-shaped cross section is inserted from the outside.
' are fitted and fixed.

The functions and effects of the above configuration will be described.

In this case, the heat generated between the rotor 6 and the friction material 1 is blocked by the heat insulating materials 5 and 5', so the brake fluid 4 in the hydraulic chamber
It has the effect of preventing the occurrence of paper and improves the performance of disc brakes.

Furthermore, the current mainstream friction material 1 is made with asbestos as its main component, and the friction material itself has excellent heat shielding properties, but asbestos is becoming increasingly difficult to use due to pollution concerns, and the friction material 1 is made of asbestos-free metallic material. Or it will be replaced by ceramic material.

If the friction material 1 is metallic, it will naturally have better heat conduction than asbestos-based friction material, and the amount of heat transferred to the brake fluid 4 will also increase, making it easier to generate paper and causing the brake paper lock phenomenon. .

From this point of view as well, it is effective to attach glass or ceramic-based heat insulating materials 5, 5' with high heat insulating properties to the end faces of the piston.

Furthermore, if the pistons 3, 3' are made of resin, it is very effective to use heat insulating materials 5, 5'.

That is, when the heat generated between the friction material 1 and the rotor 6 is directly transmitted to the end face of the resin piston through the backing plate 2, the end face may soften depending on the value of the transmitted temperature due to the resin, causing deformation of the piston and damage to the pedal. This may lead to problems such as increased stroke.

As described above, when the piston is made of metal, the main purpose is to cut off heat transfer from the backing plate 2 and prevent the generation of paper in the brake fluid 4, and when the piston is made of resin, it is mainly used to cut off heat transfer and prevent heat transfer. This has the effect of protecting the piston end face.

Note that ceramic powder bound with thermosetting resin is also effective as a heat insulating material.

Further, the damping materials 7, 7' serve to protect the heat insulating materials 5, 5' from damage against uneven loads, etc., and also serve as dampers against brake squeal, which is effective in preventing brake noise.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the outline of a flownung caliper type brake disc, Fig. 2 is a sectional view showing a piston of one embodiment of the invention, and Fig. 3 is a piston of another embodiment of the invention. FIG. 1...Friction material, 2...Backing plate, 3゜3'...Piston, 4...
Brake fluid, 5,5'... Insulation material, 6...
...Rotor, 7,7'...damping material.

Claims (1)

[Scope of utility model registration request] In a piston of a vehicle disc brake that presses a friction material facing a rotor that is interlocked with an axle via a backing plate, a damping material on the end surface side is attached to an end surface of the piston that forms a contact surface with the backing plate. A heat insulating device for a disc brake piston for a vehicle, characterized in that a heat insulating material is attached to the piston.