Integrated accelerometer assembly

• US 4,987,780 A
• Filed: 11/16/1987
• Issued: 01/29/1991
• Est. Priority Date: 11/16/1987
• Status: Expired due to Term

• Current Assignee: Litton Systems Incorporated
• Original Assignee: Litton Systems Incorporated
• Inventors: Pier, Nicholas F., Abbink, Henry C.
• Primary Examiner(s): Lobo, Ian J.
• Application Number:
  US07/121,088
• Time in Patent Office: 1,170 Days
• Field of Search: 73/514, 73/517 R, 310/329
• US Class Current: 73/514.19
• CPC Class Codes: G01P 15/093 by photoelectric pick-up

Abstract

An assembly for use in a dry accelerometer. The assembly includes a flat ceramic base with an interior aperture, two metal hinges and a pendulous mass supported within the aperture by such hinges. A light emitting diode and photodetector are provided for measuring movement of the pendulous mass. The assembly is readily fabricated and tested with batch processes.

Claims

1. An integrated accelerometer comprising, in combination:

(a) a planar support base having a central aperture;

(b) a pendulous member including two arms;

(c) a pair of spaced flexible hinges, a first end of each of said hinges being welded to said support base and a second end of each being welded to one of said arms whereby said pendulous member is pivotally supported within said aperture

(d) a pair of limit stops welded to opposed sides of said support base for limiting the movement of said pendulous member; and

(e) said support base includes a plurality of copper filled apertures for anchoring said hinge welds and said limit stop welds and said pendulous member includes a plurality of copper filled apertures for anchoring said hinge welds.

2. An integrated assembly as defined in claim 1 wherein said apertures are filled with copper.

3. An integrated assembly as defined in claim 1 wherein said plate and said pendulous member are formed of sintered aluminum oxide.

4. An integrated assembly as defined in claim 3 wherein said pendulous member further comprises:

(a) a torquer coil; and

(b) metal conductors plated on the surface of said arms of said pendulous member, said conductors being in electrical connection with said coil.

5. An integrated assembly as defined in claim 4 further including:

(a) a light emitting diode mounted in said base;

(b) a photodetector mounted in said base and spaced apart from said diode; and

(c) said pendulous member includes a shadow paddle disposed between said diode and said photodetector for disrupting a beam from said diode.

6. An integrated assembly as defined in claim 5 wherein said support base further includes metal conductors at its opposed surfaces being in electrical connection with said coil, said diode and said photodetector.

7. An integrated assembly as defined in claim 6 wherein said metal conductors of said pendulous member and said metal conductors of said base are formed of copper.