JPH08159212A - Vibration absorbing device using piezoelectric element - Google Patents

Abstract

PURPOSE: To provide a vibration absorbing device which finally consumes vibration energy as heat energy after it is converted into electric energy by a piezoelectric element. CONSTITUTION: A piezoelectric element 3 is arranged between an apparatus main body 1 and a counter mass 2 or a base stand, and a CR resonance circuit in which the piezoelectric element 3 and a resistor 4 are connected in parallel to each other is constituted. A combustible resistor can be used as the resistor 4. Therefore, the resistor 4 being a heat generating source can be arranged outside a system, highly accurate measurement, operation or the like become possible without thermal influence.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration absorbing device using a piezoelectric element for converting vibration energy into electric energy.

[0002]

2. Description of the Related Art A damper is interposed between a base and a device in order to protect various devices such as a precision measuring device and a precision processing device from the influence of externally transmitted vibrations and shocks.
This type of damper finally converts kinetic energy such as vibration into heat energy and releases it as heat energy to the outside. The damper, depending on the process of energy conversion,
Rubber that uses internal loss, one that uses an elastic body such as synthetic resin, one that uses friction loss of fluid such as oil, gas, etc. Vibration energy is converted into electric energy by a power generation mechanism, and this electric energy is used as heat. It is classified as something to consume.

The above-mentioned dampers (1) and (2) are the most widely used ones, and various types have been conventionally proposed. An eddy current damper, which consumes eddy current generated inside a conductor vibrating in a magnetic field as heat inside the conductor, belongs to the type that converts vibration energy into electric energy, for example, US Pat. No. 4,605,194.
It is introduced in the specification.

[0004]

Normally, the damper is considered to be incorporated at the beginning of the design stage of the device.
After the device is completed, it is often necessary to install it additionally.
In the conventional damper, modification or removal of the device itself is unavoidable, and additional installation cannot be easily performed. Also,
It may not be used in a vacuum system where gas generation is a concern. Moreover, in the conventional damper, since the place where the vibration energy is finally consumed as heat energy is near the device body, the device body is easily affected by heat generation. The heat effect appears as an error factor, especially for equipment that requires highly accurate measurement and processing. The present invention has been devised to solve such a problem, and by using a piezoelectric element as a power generation mechanism, a vibration absorber having a very simple structure and capable of preventing thermal influence on the device body is provided. The purpose is to provide.

[0005]

In order to achieve the object, a vibration absorbing device of the present invention has a piezoelectric element interposed between a device body and a base and a resistor connected in parallel to the piezoelectric element. And a CR resonance circuit is configured by the piezoelectric element and the resistor. Either a solid-state resistor or a variable resistor can be used as the resistor. Further, by providing a piezoelectric element around the rotary shaft or the operating shaft, it is possible to prevent the shaft from shaking or chattering.

[0006]

In the vibration absorbing device according to the present invention, the piezoelectric element converts the vibration energy into electric energy, and the resistor connected in parallel to the piezoelectric element consumes it as heat energy.
Since the frequency to be absorbed by the CR resonance circuit composed of the capacitance and resistance of the piezoelectric element is specified, the vibration energy such as the natural frequency is efficiently and selectively removed. The resistor that is the heat generating portion can be provided at an arbitrary position apart from the main body of the device. Therefore, the device body is protected from harmful heat influence. Also, if the resistor is replaced with a variable resistor, it becomes a tunable damper, and fine adjustment of the vibration system becomes possible. The vibration absorber according to the invention can be attached in various ways to the vibration source or to the device in which it is intended to prevent vibration propagation.

FIG. 1 shows the basic structure of a vibration absorber. Equipment body 1 and countermass 2 that require anti-vibration
1 and the piezoelectric element 3 is interposed therebetween. The piezoelectric element 3 has a resistor 4 as shown in FIG.
And a CR resonance circuit. The resistor 4 is preferably provided at a position away from the device body 1 so that the heat generated there is not transferred to the device body 1. On the contrary, when the influence of heat can be ignored, it is possible to integrate the piezoelectric element and the resistor into a simpler structure. The vibration energy propagated to the device body 1 is converted into electric energy by the piezoelectric element 3, extracted from the device body 1 and sent to the resistor 4 outside the system. Alternatively, the same equipment configuration is also used to prevent the vibration generated in the device body 1 from propagating to the outside.

In the resistor 4, resistance heating is generated according to the supplied electric energy, and as a result, vibration energy is consumed as heat energy. Therefore, the device body 1 is protected from vibration, and measurements and operations that require high accuracy can be performed without disturbance caused by vibration. Alternatively, the device body 1
The vibration generated in step 2 is prevented from propagating to the outside, and the adverse effects on peripheral devices are eliminated. As a method of incorporating the vibration absorbing device into the existing equipment later, for example, as shown in FIG.
The counter mass 2 is provided around the already installed device body 1, and the piezoelectric element 3 is arranged between the device body 1 and the counter mass 2.

When the vibration absorbing device is incorporated from the beginning of the installation stage of the device, the piezoelectric element 3 can be arranged by utilizing the mass of the device body 1 as shown in FIG. In this case, the piezoelectric element 3 and the cushioning material 6 are arranged between the base 5 and the equipment body 1, and the piezoelectric element 3 and the cushioning material 6 receive the mass of the equipment body 1. The vibration absorber according to the invention comprises a rotary shaft,
It is also effective in preventing blurring and chattering of the operation axis. For example, as shown in FIG. 4, the piezoelectric element 3 is arranged so as to surround the shaft 7, and the counter mass 2 is arranged concentrically with the shaft 7. The electric energy generated in the piezoelectric element 3 fluctuates along the vibration propagation direction. for that reason,
As the larger vibration is applied, the vibration energy absorbed by the piezoelectric element in that direction increases so as to cancel the shake and chatter of the shaft 7.

[0010]

EXAMPLE An example in which the present invention is applied to a probe device will be described. As shown in FIG. 5, the probe device of the present embodiment has a tube type piezo scanner 12 mounted on an L-shaped base 10 via a scanner base 11. Piezo scanner 1
The probe 13 attached to the tip of the probe 2 is directed to the sample 15 fixed to the upright portion 14 of the base 10. The scanner base 10 includes a piezoelectric element 16 and a counter mass 17 on the rear end side so that the scanner base 10 can be slightly moved by an impact force. The piezoelectric element 16 and the counter mass 17 act as a part of the damper when the scanner base is stationary.

A vibration absorbing device according to the present invention is arranged between the base 10 and the installation base 18. That is, the base 1
A cushioning material 19 is provided below the base 10 to receive a mass of 0.
And the piezoelectric element 20 is arranged. The piezoelectric element 20 is connected in parallel with an appropriate resistor 4 (see FIG. 1b) to form a CR resonance circuit. Vibrations that are about to propagate from the outside to the base 10 are piezoelectric elements 20 between the base 10 and the installation base 18.
Are converted into electric energy by the outside and taken out of the system, and consumed as heat energy. Therefore, the vibration does not propagate to the base 10 and the sample 15 can be probed with high accuracy.

[0012]

As described above, in the vibration absorbing device of the present invention, the vibration energy is converted into electric energy by the piezoelectric device and finally consumed as heat energy. This vibration absorbing device has an extremely simple structure and can be easily incorporated into an existing device to improve the vibration characteristics of the entire device. In addition, since the resistor, which is a heat source, can be placed outside the system, the device body is protected from the influence of heat, enabling highly accurate measurement and operation. Moreover, the installation conditions are not strict, and it has the advantage that it can be easily installed in a vacuum or in water.

[Brief description of drawings]

FIG. 1 shows a basic configuration of a vibration absorbing device according to the present invention, in which a piezoelectric element (a) provided between a device body and a counter mast, and a CR resonance circuit (b) including a piezoelectric element and a resistor.

[Fig. 2] Vibration absorber added to existing equipment

FIG. 3 Vibration absorber that receives the mass of the device body

[Fig. 4] Vibration absorber for preventing shaft shake and chatter

FIG. 5: Vibration absorber incorporated in the probe device

[Explanation of symbols]

1: Device body 2: Counter mass 3: Piezoelectric element 4: Resistor 5: Base 6: Buffer material 7: Shaft 10: Base 11: Scanner base 12: Piezo scanner 13: Probe 14: Standing part 1
5: Sample 16: Piezoelectric element 17: Countermass 18: Installation base 19: Buffer material 20: Piezoelectric element

Claims (4)

[Claims] 1. A CR resonance circuit comprising a piezoelectric element interposed between an apparatus body and a counter mass or a base, and a resistor connected in parallel to the piezoelectric element, wherein the piezoelectric element and the resistor are CR resonance circuits. The vibration absorbing device that is configured. 2. A vibration absorbing device, wherein the resistor according to claim 1 is a variable resistor. 3. A piezoelectric element provided around a shaft body such as a rotary shaft and an operating shaft, a counter mass concentrically arranged with the shaft body, and a resistor connected in parallel to the piezoelectric element. A vibration absorbing device comprising: a CR resonance circuit including the piezoelectric element and the resistor. 4. A vibration absorbing device, wherein the resistor according to claim 3 is a variable resistor.