| 摘要 |
<p>The improved magnetic proximity detector of the present invention includes a tubular housing (12), a tubular magnet (14) fixed in position within the housing, a first movable magnet (18) within said housing at one end of said tubular magnet, a second movable magnet (20) within the housing at the other end of the tubular magnet, an annular magnet (38) positioned in surrounding relationship to the housing, means (40, 42) for adjusting the position of the annular magnet axially with respect to said housing, means (22) connecting the first movable magnet and the second movable magnet, a switch including a blade (28), a first contact (24) and a second contact (26), and means connecting said first and second movable magnets to said blade so that movement of said first and second movable magnets moves said blade between contact with the first and second contacts. The first movable magnet (18) has its poles arranged so that it is attracted to said tubular magnet and the second movable magnet has its poles arranged so that it is repelled by the tubular magnet, the nearness of a ferrous metal (46) to the end of said housing containing said first magnet moving the two magnets and the blade to change the position of the switch, and the adjusting of the position of said annular magnet changing the flux from the end of the housing containing the first magnet to adjust the distance at which a ferrous metal causes the change of position of the switch blade.</p> |
