ACCELEROMETER

• US 3,775,684 A
• Filed: 01/16/1970
• Issued: 11/27/1973
• Est. Priority Date: 01/16/1970
• Status: Expired due to Term

• Current Assignee: Louis S. Hoodwin
• Original Assignee: Louis S. Hoodwin
• Inventors: Hoodwin, Louis S.
• Primary Examiner(s): Lynch, Michael J.
• Application Number:
  US05/003,302
• Time in Patent Office: 1,411 Days
• Field of Search: 324/162,164 310/155,168,154
• US Class Current: 324/162
• CPC Class Codes: G01P 15/00 Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
• CPC Class Codes: G01P 15/003 Kinematic accelerometers, i.e. measuring acceleration in relation to an external reference frame, e.g. Ferratis accelerometers G01P15/001, G01P15/16, G01P15/165 take precedence
• CPC Class Codes: G01P 15/005 measuring translational acceleration
• CPC Class Codes: G01P 3/49 using eddy currents

Abstract

This invention describes an accelerometer of the electromagnetic, self-generating, non-seismic type having a simplified design that permits construction at low cost.

Claims

1. An accelerometer which utilizes the secondary magnetic flux generated when an electrically conductive armature moves through a primary magnetic field, such an accelerometer having an electrically conductive armature the motion of which is to be monitored;

a core of ferromagnetic material which conducts both primary and secondary magnetic flux and is shaped to reach from one side of the armature around the edge of the armature to the other side of the armature thereby creating an air gap through which the armature moves;

a source of magnetic flux on the end of the core at the air gap, between the core and the armature, such source providing a pair of opposite poles facing toward the armature, said poles positioned so the a line joining their centers is essentially parallel to the instantaneous direction of motion of a point on the armature midway between the poles;

a pickup coil mounted encircling the magnetic structure, each structure consisting of the source of magnetic flux and the ferromagnetic core, the mounting such that the secondary flux is coupled to the coil.

2. An accelerometer according to claim 1 in which the source of magnetic flux consists of magnets of similar shape symmetrically assembled to the core on both sides of the air gap.