Ejector system for vehicle
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsYasuhiro Oi, Shigemasa Hirooka
Life of this patent
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Abstract
An ejector system controls the idle speed of an internal combustion engine by controlling an electric throttle valve system that adjusts the flow-rate of the intake air to be supplied to the internal combustion engine, and includes an ejector which generates a negative pressure of which the absolute value is larger than the absolute value of a negative pressure to be introduced from an intake manifold, a vacuum control valve which causes the ejector to operate or causes the ejector to stop operating, and an ECU that controls the vacuum switching valve. With the ejector system, even if the ejector is caused to operate or caused to stop operating, it is possible to appropriately suppress fluctuations in the idle speed, and appropriately obtain a negative pressure.
Claims10
An ejector system for a vehicle, comprising:
- an idling-timing flow-rate adjustment device that adjusts an intake air flow-rate that is a flow-rate of an intake air to be supplied to an internal combustion engine when the internal combustion engine is idling;
- an ejector that generates a negative pressure of which an absolute value is larger than an absolute value of a negative pressure to be introduced from an intake passage of an intake system of the internal combustion engine;
- a state changing device that causes the ejector to operate or causes the ejector to stop operating;
- and
- a control unit that controls the state changing device, and that controls the idling-timing flow-rate adjustment device based on an operating state of the ejector, wherein
- a flow rate of an intake air that flows through the ejector increases more moderately than a flow rate of an intake air that flows through the idling-timing flow-rate adjustment device, and
- when the intake air flow-rate is adjusted to an intake air flow-rate required by the internal combustion engine while the internal combustion engine is idling, the control unit determines whether it is possible to maintain an idle speed or control the idle speed appropriately even if the state changing device is caused to operate by determining whether an intake air flow-rate that is indicated by a predetermined control amount which need not be responsive to a change in the intake air flow-rate, from among control amounts used to control the idling-timing flow-rate adjustment device, is higher than the intake air flow-rate that increases when the ejector is caused to operate, and
- when the control unit determines that the intake air flow-rate that is indicated by the control amount which need not be responsive to the change in the intake air flow-rate, from among the control amounts for the internal combustion engine, is higher than the intake air flow-rate that increases when the ejector is caused to operate, the control unit causes the state changing device to operate before adjustment by the idling-timing flow-rate adjustment device is made.
Dependencies are inferred from the claim text.