Patent ID: 6185994
Filing Date: 2001-02-13
Classification: G01F

Abstract:
A oil level detector installed in an oil tank to detect the level of oil, comprising:a flat, circular holder base, said holder base comprising a bottom side wall, a top side wall and a closed-end tube having an interior extending downwardly from said bottom side wall substantially perpendicularly to said bottom side wall, and a flat block having a first, second, third and fourth peripheral side raised from said top side wall of said holder base, said flat block comprising a central through hole formed to be in communication with said interior of said closes-end tube, an annular groove formed at said top side wall of said flit block, said annular groove extending around said central through hole, two wire grooves respectively extended from said annular groove towards and along said first peripheral side of said flat block, and two peripheral coupling grooves, each formed at a respective one of said third and fourth opposite peripheral side of said flat block;a clamp fastened to said closed-end tube at an end remote from said holder base;an annular float mounted around said closed-end tube and movable in opposing directions along said closed-end tube between said circular holder base and said clamp, said annular float holding a plurality of magnets mounted interior thereto;an insulative sleeve mounted inside of said closed-end tube, said insulative sleeve having a bottom end and a top end;a first plug cap and a second plug cap respectively fastened to the bottom end and top end of said insulative sleeve in press-fit engagement therewith to prevent an oil leakage, said first plug cap having a periphery and a plurality of outside annular flanges raised around the periphery thereof and press-fit into the bottom end of said insulative sleeve, said second plug cap having a plurality of first outside annular flanges press-fit into the top end of said insulative sleeve, a plurality of second outside annular flanges press-fit into said central through hole at said flat block, and a plurality of axially extended wire holes;a rubber ring mounted in said annular groove around said central through hole of said flat block;a cover mounted on said flat block to hold down said rubber ring, said cover having peripheral side walls and comprising two inwardly extending coupling flanges disposed at two opposite peripheral said side walls thereof and respectively forced into engagement with said peripheral coupling grooves at said flat block, and a plurality of wire holes formed in a respective peripheral side wall of said cover and attached to the wire grooves formed at said flat block; anda detecting circuit board mounted within said insulative sleeve, said detecting circuit board being substantially completely enveloped by said insulative sleeve, said detecting circuit board comprising a plurality of vertically spaced solenoid elements for interaction with the magnets mounted in said annular float, and a plurality of lead wires respectively extended from said detecting circuit board through said wire holes formed in said second plug cap, the wire grooves formed in said flat block, and the wire holes formed in said cover.