Inertial sensors

• US 5,880,368 A
• Filed: 05/20/1997
• Issued: 03/09/1999
• Est. Priority Date: 04/19/1995
• Status: Expired due to Fees

• Current Assignee: Smiths Group plc (Smiths Group International Holdings Ltd.)
• Original Assignee: Smiths Industries Public Limited Company
• Inventors: FitzPatrick, Roger Sean
• Primary Examiner(s): Oda, Christine K.
• Application Number:
  US08/859,264
• Time in Patent Office: 658 Days
• Field of Search: 73/493, 73/494, 73/495, 73/383, 73/504.03, 73/504.04, 73/862.043, 73/431, 73/510, 73/511, 73/512, 73/382 G, 73/382 R, 73/178 R , 73/504.12, 73/335.02
• US Class Current: 73/493
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems
• CPC Class Codes: G01P 15/0888 for indicating angular acceleration
• CPC Class Codes: G01P 15/097 by vibratory elements
• CPC Class Codes: G01P 15/18 in two or more dimensions

Abstract

An inertial sensor assembly has three silicon chips that are each machined to form a respective vibrating inertial sensor, an acceleration sensor and engaging edge formations. The three chips are assembled in an orthogonal arrangement by engaging the edge formations with one another.

Claims

1. An inertial sensor assembly comprising:

first and second planar members; and

first and second inertial sensors formed from said planar members, said planar members having surface formations along edges of said members formed from material of said members, wherein said surface formations on different ones of said planar members engage one another, and wherein said surface formations mechanically support and retain said planar members in an angular relationship with one another.

2. An assembly according to claim 1, wherein said planar members are assembled in an orthogonal arrangement.

3. An assembly according to claim 1, wherein said surface formations are provided by alternate projections and recesses along said edges of said planar members.

4. An assembly according to claim 1, wherein a surface formation in at least one of said planar members is provided by at least one opening in said planar member.

5. An assembly according to claim 1 including three of said planar members assembled orthogonally with one another by engagement of said surface formations.

6. An assembly according to claim 1, wherein said sensors are solid-state vibrating inertial sensors.

7. An assembly according to claim 6, wherein each said planar member includes two inertial sensors arranged at right angles to one another.

8. An assembly according to claim 1, wherein said sensors include an acceleration sensor.

9. An assembly according to claim 1, including associated electronics for said sensors, and wherein said planar members support said associated electronics for said sensors.

10. An assembly according to claim 1, wherein said planar members intersect one another along a line, and wherein said assembly includes electrical interconnections between said planar members at locations adjacent said line of intersection.

11. An inertial sensor assembly comprising:

three planar members;

three solid state vibrating inertial sensors machined from respective ones of said planar members, said planar members having surface formations along edges of said members formed from material of said members, wherein said surface formations on different ones of said planar members engage one another, and wherein said surface formations mechanically support and retain said planar members in an orthogonal relationship with one another.

12. An inertial sensor according to claim 11, wherein each said planar member includes two vibrating inertial sensors arranged at right angles to one another, and an acceleration sensor.

13. A method of manufacture of an inertial sensor assembly comprising the steps of:

providing first and second planar members;

forming a first inertial sensor from a portion of the material of said first planar member;

forming a second inertial sensor from a portion of the material of said second planar member;

forming surface formations in said planar members from the material of said members; and

positioning said first and second inertial sensors in a desired relation to one another by engaging surface formations of said first planar member with surface formations of said second planar member such that said planar members are supported and retained in an angular relationship with one another by said engaging surface formations.

14. A method according to claim 13, wherein said inertial sensors are formed from the material of said planar members by the same technique used to form said surface formations.