Position sensor of linearly moving bodies

• US 4,210,865 A
• Filed: 12/12/1977
• Issued: 07/01/1980
• Est. Priority Date: 12/12/1977
• Status: Expired due to Term

• Current Assignee: Ivan V. Ivanov, Leopold I. Chaika, Vladimir P. Nikolaev
• Original Assignee: Ivan V. Ivanov, Leopold I. Chaika, Vladimir P. Nikolaev
• Inventors: Chaika, Leopold I., Ivanov, Ivan V., Nikolaev, Vladimir P.
• Primary Examiner(s): Rolinec, Rudolph V.
• Assistant Examiner(s): Snow, Walter E.
• Application Number:
  US05/859,792
• Time in Patent Office: 932 Days
• Field of Search: 324/206, 324/207, 324/208, 340/195, 340/196, 340/199, 318/653, 318/656, 318/657, 318/658, 176/19 R, 73/314, 73/DIG. 5
• US Class Current: 324/207.17
• CPC Class Codes: G01V 3/105 forming directly coupled primary and secondary coils or loops
• CPC Class Codes: G21C 17/12 Sensitive element forming part of control element
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors

Abstract

Disclosure is made of a position sensor comprising a plurality of inductance coils with open magnetic circuits. One of the coils has two pairs of poles. The position sensor further includes a shunting element designed for movement along the axis of the coils and connected to a moving body whose position is to be found. The shunting element has groups of holes arranged along its axis. In each group, the holes are arranged along the perimeter of the shunting element. The interpole distance of the coil with the two pairs of poles is specially selected with due regard for the diameter of the holes and the interhole spacing to ensure a high accuracy of the measurements.

Claims

1. A position sensor for determing the position of a body in linear motion comprising:

a plurality of inductance coil means, each having a primary winding and a secondary winding wound on spool like cores and coaxially spaced one after another, an additional coil means coaxially spaced after said inductance coil means and having two primary and two secondary windings, each primary and secondary winding being wound on a respective core of a two spool core, said secondary windings being connected in a measuring circuit, the secondary windings of said inductance coil means indicating coarse movement and the secondary windings of said additional coil means indicating fine movement;

a tubular shunting element arranged coaxially around said coil means and attached to said linear moving body, for movement along the axis of said coil means, and being provided with groups of holes arranged along the travel path of the linearly moving body, the holes of each group being arranged along the periphery of the shunting element, the distance L between the outer ends of said additional coil means being derived from the following relationship;

space="preserve" listing-type="equation">L=n(a+b)-1/2(a+3b),

where a is the width of a hole of the shunting element measured along the axis of its travel,

b is the distance between the groups of holes of the shunting element, and

n is a natural number beginning with n=3, said shunting element, as it moves along the axis of the coils, shunting the cores of the coils so that a signal is produced in the output circuit of a respective coil, which carries information on the position of the body in linear motion.