Browse Prior Art Database

Piezoelectric Accelerometer for Vibrational Analysis

IP.com Disclosure Number: IPCOM000044219D
Original Publication Date: 1984-Nov-01
Included in the Prior Art Database: 2005-Feb-05
Document File: 2 page(s) / 43K

Publishing Venue

IBM

Related People

Fredericks, EC: AUTHOR [+2]

Abstract

The analysis of ambient vibrations is necessary in the selection of a suitable site for high precision equipment, such as photolithographic exposure tools. The invention disclosed herein is a simple and effective accelerometer for measuring ambient vibrations. Fig. 1 shows a frontal view of the invention, and Fig. 2 shows a side cross-sectional view along the section line 2-2' of Fig. 1. A base member 4 has a generally square shape with a square central opening within which is suspended a piezoelectric plate 6. The metal electrodes 8 and 10 serve to mechanically suspend the piezoelectric plate 6 within the opening of the base member 4 so that any force applied to the plate 6 in the z direction will result in the mechanical displacement of the plate 6 with respect to the base member 4 in the z direction.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 59% of the total text.

Page 1 of 2

Piezoelectric Accelerometer for Vibrational Analysis

The analysis of ambient vibrations is necessary in the selection of a suitable site for high precision equipment, such as photolithographic exposure tools. The invention disclosed herein is a simple and effective accelerometer for measuring ambient vibrations. Fig. 1 shows a frontal view of the invention, and Fig. 2 shows a side cross-sectional view along the section line 2-2' of Fig. 1. A base member 4 has a generally square shape with a square central opening within which is suspended a piezoelectric plate 6. The metal electrodes 8 and 10 serve to mechanically suspend the piezoelectric plate 6 within the opening of the base member 4 so that any force applied to the plate 6 in the z direction will result in the mechanical displacement of the plate 6 with respect to the base member 4 in the z direction. The mounting electrodes 8 and 10 are connected to the voltmeter 12. Any mechanical flexure of the plate 6, as, for example by means of a bending moment about the x axis, will result in the production of a voltage by the piezoelectric crystalline material of the plate 6 which is picked up by the electrodes 8 and 10 and applied to the voltmeter 12. A gold-plated dot 14 is applied to the central portion of the piezoelectric plate 6 so as to serve as an inertial mass to assist in producing a flexure of the plate 6 when it undergoes an acceleration in the z direction. The inertia of the central portion of the plate 6...