摘要:
A diaphragm type flow regulator has an electrically operated bleed valve to control fluid signal pressure in a chamber on one side of the diaphragm. A valve member mounted on the opposite side of the diaphragm is moved, in response to the difference in pressure between the signal chamber and a flow regulating chamber, with respect to a valve seat for controlling flow of a compressible fluid between an inlet and outlet in the flow regulating chamber. An auxiliary chamber communicates with the flow regulating chamber through a restricting orifice which function to dampen or attenuate diaphragm vibration caused by pressure pulses or transients which may occur in the fluid supply conduit. In one arrangement the auxiliary chamber is formed as part of the regulator housing. In other arrangements, the auxiliary chamber is formed as part of a separate fitting attached to the regulator flow regulating chamber inlet.
摘要:
A diaphragm type flow regulator has an electrically operated bleed valve to control fluid signal pressure in a chamber on one side of the diaphragm. A valve member mounted on the opposite side of the diaphragm is moved, in response to the difference in pressure between the signal chamber and a flow regulating chamber, with respect to a valve seat for controlling flow of a compressible fluid between an inlet and outlet in the flow regulating chamber. An inertial mass is mounted for limited, resiliently opposed movement on the diaphragm, and serves to dampen diaphragm vibration caused by pressure pulses in the fluid supply conduit.
摘要:
A fuel vapor canister purge control valve assembly has an electric valve and a pressure regulator valve for connection at its inlet to a canister fluidically in series in a common housing. The electric valve has a spherical magnetically permeable operator biased closed against the seat by a balanced rotary armature. A C-shaped solenoid pole frame defines diametrally oppositely disposed radial working air gaps with the armature. Upon PWM energization of the solenoid, the armature rotation permits the spherical valve member to move from the seat to open the valve. A venturi is formed in the electric valve inlet and the venturi throat has a pressure tap connected to provide a reference pressure for one side of the pressure regulator diaphragm. The opposite side of the regulator diaphragm has an elastomeric obturator and is exposed to the outlet pressure of the electric valve. The elastomeric obturator is moveable with respect to another valve seat for controlling flow to the outlet for connection to an engine inlet manifold.
摘要:
A flow regulator for automotive vehicles of the type having a computer-controlled emission control system. The flow regulator has an electric vacuum regulator (EVR) valve that regulates the vacuum signal provided to a vacuum regulator valve in accordance with the current signal supplied to the EVR valve by the engine controller unit. The vacuum regulator valve includes a control chamber and a valve chamber that are separated by a movable diaphragm valve assembly. The preload on a biasing spring acting on the diaphragm valve assembly can be adjusted during calibration of the flow regulator for setting a first calibration point. An adjustable flow restrictor provided in the inlet portion of the vacuum regulator valve can be varied during calibration for setting a second calibration point. In operation, the flow regulator is operable to generate substantially linear output flow characteristic between the two calibration points as a function of the current signal in a manner that is independent of changes in manifold vacuum.
摘要:
A fuel vapor management valve or VMV having an electrically operated vent valve for controlling atmospheric bleed flow to a vacuum signal pressure chamber. The pressure in the signal pressure chamber controls the differential pressure acting on opposite sides of a diaphragm which moves a valve member for regulating fuel vapor purge flow from a canister to the engine intake manifold. Vacuum is applied to the signal pressure chamber through restrictive passages in a connector which prevent sonic flow choking. In one embodiment two orifices are spaced fluidically in series. In another embodiment fluidically parallel laminar flow passages are provided in an element comprising a porous filter preferably formed of fibrous material or sintered metal. In another embodiment, the laminar flow element is disposed fluidically in series with a flow restricting orifice.
摘要:
A fuel tank vapor management valve (VMV) for controlling purge flow from a vapor storage canister to an engine inlet manifold. In one embodiment, an existing VMV utilizing an electrically operated atmospheric bleed valve or EVR for controlling vacuum pressure on one side of the regulator valve diaphragm is modified to have an additional vacuum ported valve seat in the EVR to be opened and closed by the bleed valve instead of providing a vacuum port in the regulator diaphragm signal pressure chamber. The inlet of the EVR is connected to the storage canister instead of being ported to the atmosphere which equalizes canister pressure across the regulator diaphragm thus preventing undesired opening of the regular valve when the engine is shut off. In another embodiment, an existing VMV is unmodified, with the EVR bleed port connected to the canister and the shut-off valve is connected in the line connecting the engine manifold with the regulator valve diaphragm signal pressure chamber. The shut-off valve may be either electrically operated or pressure actuated by engine manifold vacuum.
摘要:
An electrically controlled fuel vapor canister purge pressure regulator valve assembly has the regulator valve housing formed integrally with the solenoid operated valve body. A pressure responsive diaphragm is disposed in the housing to form on opposite sides thereof, an inlet chamber and an outlet chamber. The valve body has an inlet passage communicating with the inlet chamber and an outlet passage communicating with the outlet passage. The solenoid controls by-pass flow around the diaphragm to the outlet chamber. The outlet passage is closed by a closure member defining an outlet passage and valve seat. The diaphragm has a plate thereon moveable with the diaphragm to control flow over the valve seat. The outlet closure member encloses the diaphragm periphery and is sealed to the housing by a weld ring which may be spin friction or ultrasonically welded to the housing. An inlet chamber closure member forms an inlet fitting and inlet passage and retains a filter in the inlet chamber. The inlet closure member is sealed to the housing by a weld ring similar to the outlet closure member.
摘要:
A solenoid operated valve is connected in series with a resistor and a PTC thermistor. Upon coil energization, the armature moves to close the valve member against a valve seat and further armature movement to close an air gap with a pole piece is absorbed by a spring between the armature and valve member. Upon closure of the air gap, the magnetic reluctance between the armature and pole piece is decreased such that significantly less current is required in the coil to hold the valve closed. Upon heating of the thermistor, the resistance is increased sufficiently to reduce the current to the hold-close level and less power is required thereafter to maintain the valve closed. The valve is applied to on-board vehicle diagnostic procedures performed after engine shut-down where current must be minimized to prevent battery drain to a level preventing re-start.
摘要:
A variable area valve and pressure regulator for providing fuel vapor purge control in an evaporative emission control system of an automotive vehicle. A solenoid valve assembly selectively controls fluid communication between a fuel vapor source and an intake manifold by varying the area of an orifice associated with the solenoid valve assembly. A pressure regulator assembly is responsive to pressure differentials between an inlet cavity and an outlet cavity to further control the flow through the purge regulator. In operation, the purge regulator assembly is operable to generate nonlinear output flow characteristics which are independent of changes in the intake manifold vacuum, as well as the inlet pressure, and which further provides the desired nonlinear response.
摘要:
An electrically controlled flow regulator valve assembly having a diaphragm operated pressure regulator valve with a solenoid operated valve for by-passing the diaphragm to control flow to the regulator valving chamber. In one embodiment the regulator valving chamber communicates through a small restricting orifice with a closed dampening chamber. In another embodiment a second closed dampening chamber is formed to communicate through a second small restrictive orifice with a chamber on the inlet pressure side of the diaphragm.