JPH0318754Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a brake device that obtains braking force by pressing a friction member against a braked member using the amount of strain in a piezoelectric element array.

Conventional technology Conventionally, this type of brake device uses one piezoelectric element array in which a plurality of piezoelectric elements are laminated with a piezoelectric material such as piezoelectric ceramics sandwiched between electrode plates, and a DC voltage is applied to each piezoelectric element. A system has been developed in which braking force is obtained by pressing a friction member against a braked member using the total amount of displacement obtained by adding the resulting strain in the stacking direction (Japanese Patent Laid-Open No.
(See Publication No. 60-81527).

However, in such a brake device, it is necessary to fix one end of the piezoelectric element array and leave the other end free to connect it to the movable friction member, but the impact when the brake is applied is applied to the piezoelectric element. The impact force is directly transmitted to the piezoelectric element array each time the brake is activated, and this is particularly interesting for materials such as ceramics, which have compositional characteristics that are weak against external forces from the lateral direction. It has become something that does not exist.

Furthermore, when such a brake device is used as a brake device for the wheels of an automobile, there is a problem in that shocks caused by vibrations of the automobile are directly transmitted to the piezoelectric element array.

Purpose This invention was made taking the above points into consideration.
An object of the present invention is to provide a brake device that can effectively alleviate shocks applied to a piezoelectric element array during brake operation.

Configuration In order to achieve the objective, the present invention is a brake device that uses the amount of strain in the piezoelectric element array to press a friction member against a braked member to obtain braking force, and in particular, the present invention is designed to hold the piezoelectric element array. A buffer member is provided between the holding member and the piezoelectric element array.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, this invention presses a brake pad 2 from one side of a disc rotor 1 in a wheel portion of an automobile.
In a disc-type brake device in which a disc rotor 1 is sandwiched between a brake pad 3 provided on the caliper 4 side and a braking force is applied to the disc rotor 1, a member 4 formed integrally with the disc rotor 1 on the caliper 4 side. ' via two piezoelectric element arrays 61,
62 are arranged in parallel, one piezoelectric element array 6
1 through its holding member 8 to said member 4'
At the same time, the brake pad 2 is attached to one end of the other piezoelectric element array 62 on the same side via its holding member 9, and the holding member 1 is attached between the other ends of each piezoelectric element array 61, 62.
0 and 11, respectively, and a link 12.

In this case, especially in the present invention, each piezoelectric element array 6
1 and 62 are held by holding members 8 and 9, respectively.
10, 11, the piezoelectric element array 6
A rubber ring 7 as a buffer member is inserted between each of the holding members 8, 9, 10, and 11.

As each piezoelectric element array 61, 62, as shown in FIG. It is constructed by laminating multiple layers.

The holding member 10 provided on the other end side of the piezoelectric element array 61 is free with respect to the member 4' on the caliper 4 side, and the holding member 10 is moved by displacement due to strain in the stacking direction of the piezoelectric element array 61. is adapted to slide in the direction A in the figure using a member 4' on the caliper 4 side as a guide.

Further, each of the holding members 9 and 11 provided at both ends of the piezoelectric element array 62 is free with respect to the member 4' on the caliper 4 side, and the piezoelectric element array 62 is held by using the caliper 4 and the member 4' as a guide. It is designed to be able to slide in the directions B and C in the figure.

The link 12 is formed in a substantially dogleg shape, and is connected to the support member 5 and each piezoelectric element array 61, 62 so that it can rotate like a seesaw with its bent portion as a fulcrum a.
When the piezoelectric element array 61 is distorted and the holding member 10 moves in the direction A, one end of the link 12 is pushed and rotated, and the other end of the link 12 is inserted between the This pushes the holding member 11 of the piezoelectric element array 62 in the C direction.

Further, in FIG. 1, 16 is a controller which reads a signal detected by a potentiometer 18 of the amount of depression of the brake pedal 17 and controls the controller as appropriate so that a braking force corresponding to the amount of depression is obtained. A DC voltage is applied to each piezoelectric element array 61, 62, respectively. In the figure, 19
is the power supply device.

In the brake device according to the present invention configured as described above, when the brake pedal 17 is depressed,
Under the control of the controller 16, a DC voltage corresponding to the amount of depression is applied to each piezoelectric element array 61, 62.
A predetermined amount of strain is applied to each of the piezoelectric element arrays 61 and 62 in series through the link 12 to press the brake pad 2 in the direction C in the figure.
Together with this, a predetermined braking force is applied to the disc rotor 1.

In this case, especially in the present invention, each piezoelectric element array 6
Rubber rings 7 are attached to both ends of 1 and 62.
Since the piezoelectric element arrays 61 and 62 are attached to the holding members 8, 9, 10, and 11 via the respective holding members 8, 9, 10, and 11, shocks applied from the lateral direction to the piezoelectric element arrays 61 and 62 when the brakes are applied or the car is running are effectively alleviated.

In addition, in the case of this embodiment, in order to obtain the necessary braking force, a large number of laminated piezoelectric element arrays are divided into at least two parts, and each of the divided piezoelectric element arrays 61 and 62 are arranged in parallel. and each piezoelectric element array 6
Since the braking force due to the amount of strain generated in each of the brake pads 1 and 62 is applied in series to the brake pad 2 via the link 12, a large number of laminated piezoelectric element arrays are installed in the device to obtain the necessary braking force. This allows for a good space factor.

In addition, in this case, the link 1 formed in an approximately dogleg shape
If the length of each piece in 2 is made equal, the link 12 will simply transmit the strain amount of the piezoelectric element array 61 to the piezoelectric element array 62. However, the piezoelectric element array 62 in the link 12
By making one piece on the side that comes into contact with the piezoelectric element array 61 longer than the other piece, the amount of strain in the piezoelectric element array 61 can be amplified and transmitted to the piezoelectric element array 62.

Note that if only the amount of strain is to be transmitted, instead of using the link 12 as the displacement transmission mechanism, the third
It is possible to use a ball transmission mechanism 12' as shown in the figure or other hydraulic transmission mechanisms.

Effects As described above, regarding the brake device according to the present invention,
In a device that uses the amount of strain in a piezoelectric element array to obtain braking force by pressing a friction member against a member to be braked, it is particularly important to provide a buffer between the holding member that holds the piezoelectric element array and the piezoelectric element array. This has the advantage of being able to protect the piezoelectric element array made of piezoelectric materials such as ceramics by effectively alleviating the lateral impact force applied to the piezoelectric element array when the brake is applied, etc. have.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view showing one embodiment of the brake device according to the present invention, Fig. 2 is a partially enlarged view of a piezoelectric element array used in the same embodiment, and Fig. 3 is a diagram showing another example of the displacement transmission mechanism. FIG. 2 is a front cross-sectional view showing a configuration example. 1... Disc rotor, 2, 3... Brake pad, 4... Caliper, 5... Support member, 61,
62...Piezoelectric element array, 7...Rubber ring,
8, 9, 10, 11... Holding member, 12... Link, 16... Controller, 17... Brake pedal, 18... Potentiometer, 19... Power supply device.

Claims (1)

[Scope of utility model registration request] In a braking device that obtains braking force by pressing a friction member against a braked member based on the amount of strain in the stacking direction of a piezoelectric element array in which a plurality of piezoelectric elements are laminated, there is a gap between a holding member that holds the piezoelectric element array and the piezoelectric element array. A brake device characterized in that a buffer member is provided in the brake device.