JPH02309899A - Vibration proof device for transmitter-receiver - Google Patents

Abstract

PURPOSE:To maintain the performance of the sound wave transmitter-receiver in an expected state by fitting a piezoelectric element between a sound wave transmitter receiver fitting seat and a rack, and applying the piezoelectric element with vibration opposite in phase from the vibration of the rack. CONSTITUTION:A feedback controller 6 applies a voltage to the piezoelectric element 1 according to data on the frequency and amplitude of the rack vibration outputted from the acceleration sensor 4 of the rack so that the opposite phase from the phase of the rack vibration is obtained, and then performs feedback control so as to minimize the output (fitting seat vibration) of the acceleration sensor 5 of the fitting seat. Namely, the fitting seat 3 (sound wave transmitter-receiver) is protected against the vibration of the rack 2 according to the amplitude A of the rack 2, the thickness amplitude B of the piezoelectric element 1, the amplitude C of the fitting seat 3, the vibration target value G of the fitting seat 3, and the control voltage H of the piezoelectric element 1. In this case, the piezoelectric element 1 is driven with the control voltage and vibrated B at the same frequency with and in the opposite phase from the vibration A of the rack 2, and both the vibration A and vibration B cancel each other to minimize the vibration C of the fitting seat 3.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a vibration-proofing method for preventing vibrations from a mounting frame from being transmitted to a transducer used in underwater vehicles, ships, etc. and becoming noise. Regarding equipment.

[Prior art and problems to be solved by the invention] Conventionally, this type of vibration isolation structure has been considered to use anti-vibration rubber, etc., but in the case of transducers used in underwater vehicles, ships, etc. No special anti-vibration structure was used because the anti-vibration rubber would be crushed and the anti-vibration effect would be lost.

However, there has been a problem in that mechanical vibrations such as engine vibrations are transmitted to the transducer via the pedestal and the mounting seat, adversely affecting the performance of the transducer.

The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a vibration isolating device that can effectively prevent transmission of vibration to a transducer.

[Means for Solving the Problems] A vibration isolating device for a transducer according to the present invention includes a piezoelectric element interposed between a mounting seat and a mount of the transducer, and a piezoelectric element interposed between the mounting seat and the mount, respectively. an attached acceleration sensor; and a feedback controller that suppresses vibrations of the mounting seat by applying a voltage to the piezoelectric element that generates vibrations in a phase opposite to vibrations of the pedestal based on the vibrations detected by the acceleration sensor. It is characterized by having the following.

In other words, the frequency of the frame vibration measured by the acceleration sensor,
Based on the amplitude, a voltage is applied to the piezoelectric element in the opposite phase to this vibration to cause it to vibrate, thereby suppressing the vibration of the mounting seat to a minimum.

[Example] Next, the present invention will be specifically explained based on examples.

FIG. 1 shows an embodiment of the present invention applied to a transducer for an underwater vehicle. As shown in the figure, the piezoelectric element 1 is sandwiched between a pedestal 2 and a transducer mounting seat 3. Frame 2
An acceleration sensor 4 is attached to the mounting seat 3, and an acceleration sensor 5 is attached to the mounting seat 3, respectively. The piezoelectric element 1 and the acceleration sensors 4 and 5 are connected to a feedback controller 6, and the feedback controller 6 controls the frequency and amplitude of the pedestal vibration output from the acceleration sensor 4 of the pedestal. A voltage is applied to the piezoelectric element 1 so that the phase is opposite to that of the vibration, and feedback control is performed so that the output of the acceleration sensor 5 of the mounting seat (that is, the one-dimensional seat vibration) is minimized. In the figure, 7 is a vibrator and 8 is an acoustic rubber, which constitute a transducer.

As shown in the control block diagram of FIG. 3, the vibration isolator with the above configuration has an amplitude A of the pedestal 2, a thickness amplitude B of the piezoelectric element 1, an amplitude C1 of the mounting seat 3, a vibration target value G of the mounting seat 3, Piezoelectric element 1
Based on the control voltage H, the mounting seat 3, that is, the transducer, is vibration-proofed against vibrations of the pedestal 2.

That is, as shown in FIG. 4, the piezoelectric element 1 is driven with a control voltage to vibrate B at the same frequency as the vibration A of the pedestal 2 and in the opposite phase, and the vibration C of the mounting seat 3 is caused by the cancellation of both vibrations A and B. Minimize.

FIG. 2 shows another embodiment of the present invention applied to a transducer for a ship.

In this embodiment as well, the piezoelectric element 1 is interposed between the pedestal 2 and the mounting seat 3, and the feedback controller 6 performs feedback control of the piezoelectric element 10 control voltage, and vibration of the mounting seat 3 is also suppressed to a minimum in the same manner as in the above embodiment.

[Effects of the Invention] As explained above, in the present invention, a piezoelectric element is attached between the transducer mounting seat and the pedestal, and vibrations having a phase opposite to the vibration of the pedestal are applied to the piezoelectric element. Vibration transmission can be effectively prevented, and the performance of the transducer can be maintained in the desired state.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of an embodiment of the present invention applied to a transducer for an underwater vehicle, and Fig. 2 is a longitudinal cross-sectional view of an embodiment of a pond in which the present invention is applied to a transducer for a ship. , FIG. 3 is a block diagram of the control system, and FIG. 4 is a graph showing the vibration state of each part. 1...Piezoelectric element, 2-, , , , force αm main row 3... Transducer/receiver mounting seat, 4... Acceleration sensor of pedestal, 5... Transmitting/receiving Acceleration sensor on wave device mounting base, 6...
... Feedback controller, 7... Vibrator, 8... Acoustic rubber, A... Amplitude of the pedestal, B... Amplitude of the piezoelectric element, C...・Amplitude of transducer mounting seat, G...Target value, H...Control amount. Patent Applicant: NEC Corporation Agent, Patent Attorney Kiyoshi Kuwai - 13th Sword 2 Illustration

Claims (1)

[Claims] A piezoelectric element is interposed between the mounting seat of the transducer and the mount, an acceleration sensor is attached to the mounting seat and the mount, and the vibration of the mount is detected based on the vibration detected by the acceleration sensor. 1. A vibration isolating device for a transducer, comprising: a feedback controller that suppresses vibrations of the mounting seat by applying a voltage that generates vibrations of opposite phase to the piezoelectric element.