Patent · US Expired

Magnetic sensing proximity detector

US4837539A · kind A · utility

70Cited by
7References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 8, 1987
Grant dateJun 6, 1989
Priority date
Expiry dateDec 8, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H36/008
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The improved magnetic proximity detector includes a tubular housing, a tubular magnet fixed in position within the housing, a first movable magnet within the housing at one end of the tubular magnet, a second movable magnet with the housing at the other end of the tubular magnet, an annular magnet positioned in surrounding relationship to the housing and being adjustable axially with respect to the housing, a switch having a blade, a first contact and a second contact, a connection extending between the first and second movable magnets and to the switch blade to move the switch blade responsive to movement of the magnets, the poles of the first movable magnet arranged so that the magnet is attracted to the tubular magnet, the poles of the second movable magnet arranged so that the magnet is repelled by the tubular magnet, the end of the housing containing the first movable magnet moving the two magnets responsive to ferrous metal in close spaced relationship to such end to change the position of the blade switch and the movement of the annular magnet changing the focus of the flux from the end of the housing containing the first magnet to adjust the distance at which the presence o…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.