Electronic control unit
AssigneeDenso Corporation
InventorsYuichi Aotsuka, Naoya Wakayama
Life of this patent
Estimating the term…
Abstract
A fuel injection device includes a first driver for driving a first valve and a second driver for driving a second valve. A control device performs an open control of the first valve multiple times by using the first driver, for enabling multistage fuel injection from an injection hole in one fuel cycle of an internal combustion engine via a high pressure fuel passage. The control device performs an open-close control of the second valve by using the second driver during an open control of the first valve by using the first driver, for controlling an inclination of injection rate of the fuel injection. The control device stops an output of a drive signal to the second driver when detecting an overheat of a drive circuit based on a temperature detection result of a temperature sensor.
Claims9
An electronic control device of a fuel injection control system including:
- a fuel injector including:
- a nozzle needle injecting fuel from an injection hole, the injected fuel supplied from a common rail via a high pressure fuel passage;
- a control chamber controlling fuel to be injected from the injection hole of the nozzle needle beside storing fuel on a back of the nozzle needle;
- a hydraulic driven valve disposed in the control chamber and passively operable according to a pressure of the high pressure fuel passage and the control chamber;
- a first orifice restricting a first passage in the hydraulic driven valve;
- at least one second orifice restricting each of at least one second passage that connects the control chamber and a low pressure chamber without passing an inside of the hydraulic driven valve;
- a first valve establishing and interrupting communication via the first orifice;
- a second valve establishing and interrupting communication via the second orifice;
- a first driver driving the first valve;
- a second driver driving the second valve;
- and
- the low pressure chamber disposed to discharge fuel not injected from the injection hole;
- and
- the electronic control device performing an open control of the first valve by using the first driver multiple times in one fuel cycle of the internal-combustion engine for multi-stage fuel injection from the fuel injection hole via high pressure fuel passage, and enabling a control of a slope of an injection rate of fuel injection by performing an open-close control of the second driver during the open control of the first valve by the first driver, the electronic control device comprising:
- a drive circuit configured to output a drive signal to first and second drivers;
- and
- a temperature detector configured to detect a temperature of the drive circuit, wherein
- the drive circuit, upon detection of an overheat of the drive circuit based on a temperature detection result by the temperature detector, stops output of the drive signal to the second driver.
Dependencies are inferred from the claim text.