摘要:
An on-board diagnostic system for an evaporative emission control system (10) of an internal combustion engine (12) powered vehicle employs a positive displacement reciprocating pump (24) to create in evaporative emission space a pressure that differs significantly from ambient atmospheric pressure. The pump (24) is powered by using engine intake manifold vacuum to force an intake stroke during which both an internal spring is increasingly compressed and a charge of ambient atmospheric air is created in an air pumping chamber space. Vacuum is then removed, and the spring relaxes to force a compression stroke wherein a portion of the air charge is forced into the evaporative emission space. The rate at which the pump reciprocates to alternately execute intake and compression strokes indicates the pressure and flow through a leak in the evaporative emission space. Detection of this rate serves as a measurement of leakage for the purpose of distinguishing integrity of the evaporative emission space from non-integrity.
摘要:
An assembly (12) for testing an evaporative emission control system (10) of an automotive vehicle which controls emission of volatile fuel vapors. The assembly is used to determine if a leak is present in a portion of the system which includes a vapor collection canister (14). The leak detection assembly incorporates a vacuum actuated canister vent control valve (32) which seals the evaporative system so the leak detection test can be performed. A vacuum actuated pump (28) performs a leak detection test. An engine control (26) initialize the pump by drawing air into a pump cavity and also closes the vent control valve (32). After the initialization period, the pump is activated to pressurize the evaporative emission control system. Once a control pressure is achieved, the cycle rate starts to drop off. If no leak, the pump will continue to pump at a rate that will be representative of the flow characteristics of the size of the leak. After the test has been concluded, the vent control valve (32) will unseal the system after the vacuum has been bled out through the orifice/check valve (31) that has been holding the seal during the test.
摘要:
An on-board diagnostic system for an evaporative emission control system (10) of an internal combustion engine (12) powered vehicle employs a positive displacement reciprocating pump (24) to create in evaporative emission space a pressure that differs significantly from ambient atmospheric pressure. The pump (24) is powered by using engine intake manifold vacuum to force an intake stroke during which both an internal spring is increasingly compressed and a charge of ambient atmospheric air is created in an air pumping chamber space. Vacuum is then removed, and the spring relaxes to force a compression stroke wherein a portion of the air charge is forced into the evaporative emission space. The rate at which the pump reciprocates to alternately execute intake and compression strokes indicates the pressure and flow through a leak in the evaporative emission space. Detection of this rate serves as a measurement of leakage for the purpose of distinguishing integrity of the evaporative emission space from non-integrity.
摘要:
Die Erfindung betrifft einen Vakuummotor (1) aufweisend einen Arbeitskolben (12), einen Innenraum, in dem der Arbeitskolben (12) linear beweglich angeordnet ist, ein Rückstellelement (22), das zumindest zeitweise eine in Richtung einer Vorderseite (4) des Innenraums wirkende Kraft auf den Arbeitskolben (12) ausübt, eine Gaseinlassöffnung (24) zum Einspeisen von Umgebungsluft oder eines unter Druck stehenden Gases in den Innenraum und eine Gasauslassöffnung (26) zum Abführen des Gases aus dem Innenraum, wobei die Gasauslassöffnung (26) an eine Unterdruckquelle anschließbar ist, wobei zwischen dem Arbeitskolben (12) und einer Rückseite (6) des Innenraums ein Steuerkolben (14) linear beweglich im Innenraum angeordnet ist, wobei der Steuerkolben (14) in einer ersten Position die Gasauslassöffnung (26) nicht abdeckt und die Gaseinlassöffnung (24) abdeckt und in einer zweiten Position die Gaseinlassöffnung (24) nicht abdeckt und die Gasauslassöffnung (26) abdeckt, der Steuerkolben (14) gegen den Arbeitskolben (12) beweglich gelagert ist und an dem Arbeitskolben (12) und/oder dem Steuerkolben (14) ein Mitnehmerelement (18, 20, 42) und/oder ein Abstandhalter angeordnet ist, wobei das Mitnehmerelement (18, 20, 42) bei einer Bewegung des Arbeitskolbens (12) zur Vorderseite (4) des Innenraums hin den Steuerkolben (14) in die erste Position überführt und wobei das Mitnehmerelement (18, 20, 42) oder der Abstandhalter bei einer Bewegung des Arbeitskolbens (12) zur Rückseite (6) des Innenraums hin den Steuerkolben (14) in die zweite Position überführt. Die Erfindung betrifft auch ein Lavage-System aufweisend zumindest einen solchen Vakuummotor (1), bei dem mit dem Vakuummotor (1) oder den Vakuummotoren (1) ein periodischer Sprühstoß mit einer Flüssigkeit erzeugbar ist sowie die Verwendung eines solchen Vakuummotors (1) als Motor für ein Lavage-System, einen Klopfermotor, einen Vibrationsmotor, als Antrieb für eine Dosiervorrichtung, als Rüttelmotor oder als Pumpe. Schließlich betrifft die Erfindung auch ein Verfahren zum Erzeugen einer periodischen Bewegung mit einem Vakuum oder einem Unterdruck und ein Verfahren zum Erzeugen eines Sprühstoßes mit einem solchen Verfahren.
摘要:
A pump has a PVC "T" shaped member having an inlet, an outlet and an interior pumping chamber positioned between the inlet and outlet; a piston displaceable into the chamber; an air cylinder for driving the piston into the chamber; a spring for biasing the piston outwardly from the chamber in opposition to force applied by the air cylinder; a washer-urethane disk check valve at the conduit inlet permitting fluid flow into the chamber but precluding fluid flow out of the chamber responsively to piston displacement into the chamber; and a washer-urethane disk check valve at the conduit outlet permitting fluid flow out of the chamber responsively to fluid pressure increase resulting from piston displacement into the chamber.
摘要:
An assembly (12) for testing an evaporative emission control system (10) of an automotive vehicle which controls emission of volatile fuel vapors. The assembly is used to determine if a leak is present in a portion of the system which includes a vapor collection canister (14). The leak detection assembly incorporates a vacuum actuated canister vent control valve (32) which seals the evaporative system so the leak detection test can be performed. A vacuum actuated pump (28) performs a leak detection test. An engine control (26) initialize the pump by drawing air into a pump cavity and also closes the vent control valve (32). After the initialization period, the pump is activated to pressurize the evaporative emission control system. Once a control pressure is achieved, the cycle rate starts to drop off. If no leak, the pump will continue to pump at a rate that will be representative of the flow characteristics of the size of the leak. After the test has been concluded, the vent control valve (32) will unseal the system after the vacuum has been bled out through the orifice/check valve (31) that has been holding the seal during the test.