Lubricant applying system and injector means

Abstract

A lubricant applying system which may have a plurality of lubricant injectors along a lubricant supply/return passage which receives lubricant under predetermined pressure through one end from a source for discharging and sequentially recharging the injector in one phase and in a second phase after the recharging permitting return of surplus lubricant from the injector through the passage to the lubricant source. A pressure sensor connected to the opposite end of the passage monitors pressure conditions in the passage. The lubricant injector has a displacement plunger and a cooperatively related metering plunger. The displacement plunger is responsive to lubricant passage line pressure which drives the displacement plunger in a displacement stroke, during which a passageway is connected by the displacement plunger with a metering chamber from which the metering plunger is driven by the pressure and the metering chamber charged while the metering plunger closes the lubricant passage. Upon release of pressure the displacement plunger is biased in a return stroke, and the metering plunger is biased into a metering stroke for driving the charge of lubricant from the metering chamber into a displacement chamber at the inner end of the displacement plunger. This also opens the lubricant passage for return of surplus lubricant to the source.