JPS62155347A - Active vibrationproof supporting device - Google Patents

Abstract

PURPOSE:To prevent the piezoelectric actuators from being damaged and obtaining an effective vibrationproof supporting device by constituting the captioned device so that the shift of a supporting base is absorbed by extending and contracting the upper and lower piezoelectric actuators according to the vibration of a vibrating source. CONSTITUTION:The upper and lower piezoelectric actuators 32 and 33 are extended by applying an initial voltage V0, and the gap DELTAl/2 between the hollow chamber 24 and a casing 14 is reduced to zero. When, in this state, the supporting part 2 of a vibrating source vibrates in the direction of arrows A and B, a variable load acts onto a vibrationproof supporting device, and is detected by a load detector 5, and input as a load signal Vf into a calculation part 38. The piezoelectric actuators 32 and 33 are extended and contracted by the signal supplied from the calculation part 38, and an installation rod 25 shifts up and down together with an intermediate member 9, and the propagation of the force to an installation base 4 due to the vibration of the supporting part 2 is suppressed. Further, in case of the low frequency vibration (large load), the piezoelectric actuators 32 and 33 are not applied with a load by the aid of a damper mechanism 23, and the actuator is prevented from being damaged.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an active vibration isolating support device that suppresses vibrations from an excitation source from propagating to a support device that supports an excitation source, and particularly relates to an active vibration isolation support device that suppresses vibrations from an excitation source from propagating to a support device that supports an excitation source. The present invention relates to an active anti-vibration support device using an actuator.

[Conventional technology and its problems]

Mechanical vibration of structural members is caused by the propagation of vibration from the vibration source, and one way to suppress the vibration from propagating to the support device that supports the vibration source is to install a shield at the support end of the vibration source. A passive method of inserting a swinging rubber has commonly been used. Anti-vibration rubber.

Although it has a suppressing effect over a wide frequency band, it is known that the suppressing effect is insufficient for the propagation of periodic and large vibrations.

For this reason, active vibration isolation, so-called active vibration isolation, has come to be considered. This is a method that actively attempts to cancel vibrations based on signals obtained from the vibration source. The first is an active anti-vibration support device using a hydraulic actuator, which has been proposed many times in the past, but with this device, the frequency that can be used for anti-vibration control is 0 to 1,000 Hz.
There was a problem in that high-frequency vibration isolation control was impossible. The second is an active anti-vibration support device using piezoelectric actuators.
Although vibration isolation at high frequencies up to about 6,000 Hz is possible, the plurality of piezoelectric element disks constituting the piezoelectric actuator are weak against tensile force, bending force, and torsional force, and can only generate compressive force. In addition, when the vibration source is at a low frequency and a large load is applied to the vibration isolating support device,
There is a problem in that a large load is applied to the piezoelectric actuator, and the displacement of the piezoelectric actuator is restricted and the piezoelectric actuator is damaged.

This invention was made to solve the above problems, and its purpose is to control the amount of extension of the piezoelectric actuator according to the mechanical vibration of the vibration source, thereby controlling the propagation of vibration itself to the support device. An object of the present invention is to provide an active vibration damping support device which suppresses the vibration and prevents a load from being applied to a piezoelectric actuator when the vibration of an excitation source has a low frequency.

[Means for solving problems]

In order to achieve the above object, the present invention (specific invention) includes an outer cylinder fixed to a support base, a cylindrical casing attached to the inner surface of the outer cylinder, and a cylindrical casing attached to the support base via an elastic body. Divided into two by a cutout fixed to the attached intermediate member,
and the attachment that is slidably inserted into the casing is a rod, and the attachment is attached at a constant interval to first and second storage portions formed in the partition of the rod and the space of the casing. A pair of piezoelectric actuators are inserted into the rod and controlled based on vibrations from an excitation source. The present invention (second invention) also provides an outer cylinder fixed to a support base, a cylindrical casing attached to the inner surface of the outer cylinder, and an intermediate member attached to the support base via an elastic body. The casing is divided into two parts by a fixed partition and is slidably fitted into the casing with a rod.

The attachment is inserted into the rod at a constant interval in the first and second storage areas formed by the partition of the rod and the space of the casing, and is controlled based on vibrations from an excitation source. A pair of piezoelectric actuators are provided, and the outer cylinder and the casing are connected by a damper mechanism.

[Effect]

According to the above configuration, by controlling the voltage of the pair of piezoelectric actuators incorporated in the vibration system of the vibration source in accordance with the amplitude and frequency of vibration, highly responsive and highly accurate vibration-proof support is performed.

Furthermore, when the vibration of the excitation source has a low frequency, the damper mechanism acts and the casing housing the pair of piezoelectric actuators is not displaced, so no load is applied to the piezoelectric actuators.

〔Example〕

The present invention will be explained below based on embodiments shown in the drawings.

As shown in FIG. 4, the active vibration isolation support device of the present invention inserts the vibration source 1 between the support section 2 and the mounting table 4.

A load detector 5 is fixed to a mounting base 4 which is placed facing the support part 2 at a constant distance Q, and the upper surface of a fixing member 6 fixed to the upper part of the load detector 5 and the support part 2 A first elastic body 8, an intermediate member 9, and a second elastic body 10 are arranged in a stacked manner from below to above between the lower surface and the lower surface. The load detector 5 includes a strain gauge and a piezoelectric load sensor.

The first and second elastic bodies 8 and 10 are made of anti-vibration rubber, which is an example of an elastic material.

A hollow cylindrical outer cylinder 11 is fixed to the upper surface of the support part 2 on the same axis Y-Y as the load detector 5, and a hollow cylindrical outer cylinder 11 is fixed on the top surface of the outer cylinder 11 to extend into the hollow chamber 11a. A piston 12 is disposed on the axis YY.

A casing 14 is housed in the hollow chamber 11a of the outer cylinder 11, and the piston 12 is fitted into a hollow oil chamber 16 formed in the upper part of the casing 14 with a predetermined gap in the vertical direction. . In addition, at the top of the casing 14,
Flow paths 18 and 20 are formed that communicate with the upper and lower surfaces of the oil chamber 16, and these flow paths 18 and 20 are connected to a flow rate adjusting throttle 2.
1 and communicated by a flow path 22. That is, the piston 12, the oil chamber 16. A damper mechanism 23 is constituted by the flow paths 18, 20, 22 and the flow rate adjustment throttle 21. Further, a space 24 is formed in the lower part of the casing 14.

A mounting rod 25 is fixed to the upper surface of the intermediate member 9 by a nut 26, which is disposed orthogonally on the axis Y-Y.
Communication holes 28 and 3 communicate with the upper and lower ends of 4, respectively.
It is inserted into 0.

At the upper end of the communication hole 28, a space 31 is formed at the upper end of the rod 25 for attachment. The mounting rod 25 is divided into two parts, upper and lower, by a flange portion 25a, which is an example of a partition formed in the middle portion, and an upper piezoelectric actuator 32 is mounted on the upper mounting rod 25b, which is one half of the mounting rod 25. The lower piezoelectric actuator 33 is attached to the lower part of the rod 25c, which is an alternative part of the rod 25, to the first and second housing portions 24A formed by the flange portion 25a and the space 24 of the casing 14.

24B at a constant interval ΔQ/2.

The piezoelectric actuators 32, 33 are formed of a plurality of piezoelectric element disks 35 made of piezoelectric ceramic such as zircon or lead titanate.

2 and 3 show examples of cross-sectional shapes of the piezoelectric element disk 35. FIG. 2 shows the piezoelectric element disk 35 with a cylindrical cross section, and FIG. 3 shows a plurality of piezoelectric element disks 35 with a prismatic cross section, for example. A case is shown in which four piezoelectric element ice cubes 35 are arranged.

The calculation unit 38 calculates the vibration source 1 detected by the load detector 5.
Piezoelectric actuator according to the varying load due to 32.33
The amount of elongation is determined, and the amount of voltage control applied to the piezoelectric actuators 32 and 33 necessary to generate this amount of elongation is calculated. The amplification unit 4° amplifies the output voltage from the calculation unit 38 to the voltage applied to the piezoelectric actuators 32 and 33.

Next, the operation of the embodiment of the present invention will be explained.

First, when operating the vibration isolating support device 3, an initial voltage v0 is applied to the upper and lower piezoelectric actuators 32, 33, and each piezoelectric actuator 32, 33 is expanded.

and each piezoelectric actuator 32, 33 and casing 1
The gap ΔQ/2 with the hollow chamber 24 of No. 4 is eliminated.

When the support portion 2 of the vibration source 1 vibrates in the direction of arrow A-B in this state, a variable load acts on the vibration isolation support device 3. This fluctuating load is detected by the load detector 5, and the load signal V
It is input to the calculation unit 38 as f. Through the arithmetic processing of the arithmetic unit 38, voltage signals v1 and v2 corresponding to the amount of extension of the piezoelectric actuators 32 and 33 that control the propagation of vibration from the excitation source 1 are obtained. This voltage signal V1. V, is amplified by the amplifying section 40 to the voltages Va, Va, applied to the piezoelectric actuators 32, 33.

Then, in the displacement direction 1 of the support part 2 of the excitation source 1, for example, in the displacement direction of arrow A in FIG. , =V, and -ΔV are applied, respectively, and the upper piezoelectric actuator 32 expands, while the lower piezoelectric actuator 33 contracts. As a result, the attachment rod 25 moves downward together with the intermediate member 9. In the opposite case.

That is, with respect to the displacement direction (downward direction) of the support part 2 of the excitation source 1, the voltage Va1=V, -ΔV is applied to the upper piezoelectric actuator 32, and the voltage Va1=V, -ΔV is applied to the lower piezoelectric actuator 3.
Voltages Va2=V and +ΔV are respectively applied to 3, the upper piezoelectric actuator 32 contracts, and the lower piezoelectric actuator 33 expands. As a result, the mounting rod 25 moves upward together with the intermediate member 9. In this way, during installation due to vibration of the support part 2 of the vibration source 1, propagation of force to the stand 4 is suppressed, and vibration of the stand 4 during installation is prevented.

In this case, in response to the high frequency displacement generated by the piezoelectric actuators 32 and 33, the flow path 22 is
Since the piston 12 is restricted by the oil chamber 16, there is no movement of oil within the oil chamber 16, and the piston 12 does not move. Therefore, the outer cylinder 11, the casing 14, and the piston 12 can be regarded as an integral rigid body, and the force for active vibration isolation is transmitted to the intermediate member 9 through the mounting rod 25, and the fluctuating force of the load detector 5 The active anti-vibration effect will be generated by setting the value to zero.

In the case of high-frequency vibrations that cannot be tracked by the piezoelectric actuators 32, 33, the vibrations are passively damped by the first elastic body 8. Also piezoelectric actuator 32.3
3. When inactive, the vibration source 1 is supported by the first and second elastic bodies 8 and 10.

In addition, when the distance Q between the support part 2 and the installation platform 4 changes due to the shaking of the ship, for example, when the distance Ω changes due to low frequency vibration, the oil passes through the flow path 22. The piston 12 moves by flowing into either the flow path 18 or 20, and therefore the installation is done by the rod 25,
In other words, no load is applied to the piezoelectric actuators 32 and 33. In this way, no load is applied to the piezoelectric actuators 32 and 33 by the damper mechanism 23 against vibrations of the electric layer wave number, so there is no risk of the piezoelectric actuators 32 and 33 being damaged. do not have.

〔Effect of the invention〕

As described above, according to the present invention, the upper and lower piezoelectric actuators are expanded and contracted in response to the vibration of the vibration source to absorb the displacement of the support base, so that the active vibration isolation effect can be sufficiently generated. can. Furthermore, since the damper mechanism does not apply any load to the piezoelectric actuator due to low frequency vibrations, there is no risk of the piezoelectric actuator being damaged.

[Brief explanation of drawings]

The drawings relate to embodiments of the present invention; FIG. 1 is a configuration diagram of an active vibration isolation support device, FIG. 2 is a cross-sectional view of a cylindrical piezoelectric element disk, and FIG. 3 is a cross-sectional view of a prismatic piezoelectric element disk. , FIG. 4 is a diagram showing how the active vibration damping support device is installed. DESCRIPTION OF SYMBOLS 1... Vibration source, 2... Support part, 3... Vibration isolating support device, 8.10... Elastic body, 9... Intermediate member, 11... Outer cylinder, 14... casing, 23... damper mechanism; 24...Space part, 24A...First storage part, 24B...Second storage part, 25...Mounting rod, 25a...Flange part which is an example of partition part,
32.33...Piezoelectric actuator.

Claims (2)

[Claims] (1) An outer cylinder fixed to a support base, a cylindrical casing attached to the inner surface of the outer cylinder, and a partition part fixed to an intermediate member attached to the support base via an elastic body.
a mounting rod that is separated and slidably fitted into the casing; An active vibration isolation support device comprising a pair of piezoelectric actuators inserted into a mounting rod and controlled based on vibrations from a vibration source. (2) An outer cylinder fixed to a support base, a cylindrical casing attached to the inner surface of the outer cylinder, and a partition part fixed to an intermediate member attached to the support base via an elastic body.
a mounting rod that is separated and slidably fitted into the casing; An active vibration isolation support device comprising: a pair of piezoelectric actuators inserted into a mounting rod and controlled based on vibrations from an excitation source; and the outer cylinder and casing are connected by a damper mechanism.