Valve actuating means

Claim 2

Hydraulic actuating means for a spring-returned admission valve of a reciprocating expansion motor comprising a slave cylinder, a slave piston in said cylinder operatively connected to said admission valve, a spill port in said slave cylinder uncovered by said slave piston at a point in its travel corresponding to the fully open position of said admission valve to thereby determine the stroke of said slave piston, pump means including a reciprocable plunger and a pump chamber connected to said slave cylinder, rotary cam means operable to initiate displacement of said plunger at a constant angular position of said cam means to deliver oil under pressure from said pump chamber to said slave cylinder, oil supply means, means connecting said oil supply means to said pump chamber and including an automatic non-return filling valve for said pump chamber, said filling valve including an annular plate valve member spring-biased towards a closed position and movable to an open position during the suction stroke of said plunger to deliver oil from said supply means to said pump chamber, and controllable spill means for spilling oil from said pump chamber, said spill means including adjustable means movable axially along said pump plunger and operable to spill oil from said pump chamber at any desired point in the delivery stroke of said plunger to thereby determine the duration of opening of said admission valve.

Claim 3

Hydraulic actuating means as defined in claim 1, wherein said controllable spill means comprises a transverse duct foRmed in said pump plunger and a passageway extending between said transverse duct and the delivery end of said plunger, and said adjustable means comprises a normally stationary control sleeve adjustable axially along said plunger and operable to uncover said transverse duct at a desired point in the delivery stroke of said plunger.

Claim 4

Hydraulic actuating means as claimed in claim 2 including a control shaft having eccentric means engageable with said control sleeve and means to turn said shaft and thereby displace said sleeve axially of said plunger.

Claim 5

Hydraulic actuating means as defined in claim 2, wherein said oil supply means comprises a low pressure oil chamber separated from said pump chamber by said annular plate valve member.

Claim 6

Hydraulic actuating means as defined in claim 4, wherein said annular plate valve member surrounds the delivery end of said pump plunger and controls the flow of oil through a passageway connecting said low pressure chamber to said pump chamber.

Claim 7

A reciprocating expansion motor comprising a crankcase, a cylinder mounted on said crankcase, a piston reciprocable in said cylinder, a crank drive connected to said piston, a spring returned admission valve for controlling the flow of fluid to said cylinder, hydraulic actuating means for said admission valve including a slave cylinder, a slave piston in said cylinder operatively connected to said admission valve, a spill port in said slave cylinder connected to said crankcase and uncovered by said slave piston at a point in its travel corresponding to the fully open position of said admission valve to thereby determine the stroke of said slave piston, pump means including a reciprocable plunger and a pump chamber connected to said slave cylinder, rotary cam means driven from said crank and operable to initiate displacement of said plunger at a constant angular position of said cam means to deliver oil under pressure from said pump chamber to said slave cylinder, oil supply means connected to said crankcase, means connecting said oil supply means to said pump chamber and including an automatic non-return filling valve for said pump chamber, said filling valve including an annular plate valve member spring-biased towards a closed position during the delivery stroke of said plunger and movable to an open position during the return stroke of said plunger to deliver oil from said supply means to said pump chamber, and controllable spill means for spilling oil from said pump chamber back to said oil supply means, said spill means including adjustable means movable axially along said pump plunger and operable to spill oil from said pump chamber at any desired point in the delivery stroke of said plunger to thereby determine the duration of opening of said admission valve.

Claim 8

A reciprocating expansion motor comprising a crankcase, a cylinder mounted on said crankcase, a piston reciprocable in said cylinder, a crank drive connected to said piston, a spring returned admission valve for controlling the flow of fluid to said cylinder, hydraulic actuating means for said admission valve including a slave cylinder, a slave piston in said cylinder operatively connected to said admission valve, a spill port in said slave cylinder connected to said crankcase and uncovered by said slave piston at a point in its travel corresponding to the fully open position of said admission valve to thereby determine the stroke of said slave piston, pump means including a reciprocable plunger and a pump chamber connected to said slave cylinder, rotary cam means driven from said crank and operable to initiate displacement of said plunger at a constant angular position of said cam means to deliver oil under pressure from said pump chamber to said slave cylinder, oil supply means connected to said crankcase, means connecting said oil supply means to said pump chamber and including an automatic non-return filling valve for said pump chamber, said filling valve including an annular plate valve member spring-biased towards a closed position during the delivery stroke of said plunger and movable to an open position during the return stroke of said plunger to deliver oil from said supply means to said pump chamber, and controllable spill means for spilling oil from said pump chamber back to said oil supply means, said spill means including adjustable means movable axially along said pump plunger and operable to spill oil from said pump chamber at any desired point in the delivery stroke of said plunger to thereby determine the duration of opening of said admission valve.