초록 ▼

A solenoid operated exhaust bleed type pressure control valve assembly providing a proportional pressure control signal over the full range of solenoid operating current. A poppet valve member is connected to the solenoid armature and closes against a valve seat in the control signal port pressure c

A solenoid operated exhaust bleed type pressure control valve assembly providing a proportional pressure control signal over the full range of solenoid operating current. A poppet valve member is connected to the solenoid armature and closes against a valve seat in the control signal port pressure chamber to prevent flow through the valve seat to the exhaust (bleed) ports. This results in very low or reduced leakage at minimum pressures. The poppet valve contacts a projection on a spool valve for effecting concurrent movement therewith for valving a supply pressure port in the control signal pressure chamber. In the normally closed version of the valve assembly, the poppet delays the spool opening of the inlet or supply port until solenoid current has reached about Five to Twenty Percent (5-20%) of maximum. In the normally open version, the spool is delayed in closing the supply inlet port until solenoid current reaches about Eighty to One Hundred Percent (80-100%) of maximum.

대표청구항 ▼

1. A solenoid operated valve assembly for variable pressure bleed proportional control comprising:(a) a valve body having a valving bore with a valving spool moveably disposed therein and an inlet port communicating with said bore and a control pressure outlet port communicating with said bore and a

1. A solenoid operated valve assembly for variable pressure bleed proportional control comprising:(a) a valve body having a valving bore with a valving spool moveably disposed therein and an inlet port communicating with said bore and a control pressure outlet port communicating with said bore and axially spaced from said inlet port, said bore having an end wall with an aperture therethrough and a valve seat formed about said aperture on the side of said wail opposite said bore; (b) an exhaust port communicating with said valve seat; (c) a solenoid coil attached to said body and having an armature moveably disposed therewith and operable for movement in response to electrical energization of said coil and including a valve member operable for contacting and sealing on said valve seat and blocking flow thereacross, wherein upon de-energization of said coil said valve member is biased to a position contacting and sealing said valve seat and upon energization of said coil progressively from Zero to One Hundred Percent (0-100%) of maximum current, said valve member is proportionately moved away from said valve seat and said spool is moved to a position blocking said inlet when said coil is energized in the range of about Eighty to One Hundred Percent (80-100%) of maximum coil energization.