04168413 is referenced by 47 patents and cites 4 patents.

A piston detector switch adapted to be positioned on a pipe having an orifice in the wall thereof which may be briefly described as comprising a plate securable to the pipe having a bore extending therethrough in open communication with the pipe orifice, a valve seat positioned in the bore adjacent the pipe surface, a ball loosely positioned in the bore, having a diameter such that a portion of the ball normally protrudes within the pipe interior when seated, a housing sealably secured to the plate having a duct extending therethrough in open communication with the bore, and magnetically responsive switch means disposed in said duct for signalling movement of the ball from the seated position and for preventing fluid leakage from said duct.

Title
Piston detector switch
Application Number
5/885803
Publication Number
4168413
Application Date
March 13, 1978
Publication Date
September 18, 1979
Inventor
Joseph C Halpine
1908 W. Latimer Pl., Tulsa, 74127
OK, US
Agent
Head Johnson & Chafin
IPC
H01H 35/38
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