GB1297703A - - Google Patents

Abstract

1297703 Reciprocating pumps for maintaining lubricant level in IC engine crank-cases R E NELSON 27 Feb 1970 [9 July 1969] 9605/70 Headings F1A and F1B [Also in Divisions G1 and H3] The level 16 of lubricant in an I.C. engine crank-case 15 is maintained at a predetermined level by an electrically operated pump 10 which ceases to pump lubricant from a reservoir 12 into the crank-case when a dip-tube 26 is covered by the lubricant. The pump comprises a piston 51 reciprocable in a cylinder 36, thereby to draw lubricant in a chamber 42 past an inlet valve 62 and deliver it past a spring urged ring valve 55 into a chamber 40 having an outlet 43 to the crankcase. The chamber 40 is bounded on one side by a diaphragm 31 reciprocated with the piston 51. When the dip tube becomes submerged air is trapped in the chamber 40 preventing movement of the diaphragm and piston. The piston is reciprocated by a solenoid 71 energized by a pulsed electric supply produced in an A.C. or D.C. energized oscillator circuit, (See Divisions H3-5). A core 76 fixed to the piston is moved by the solenoid through either the suction or delivery stroke, the other stroke being effected by a spring. A further or alternative dip tube may lead to the chamber on the other side of the diaphragm 31, in which case the solenoid is disposed in sealed chamber, Figs.3, 4, 10 and 11 (not shown).