Abstract: An EGR valve device includes a valve housing of which inside exhaust gas passes through, a poppet valve as a valve body accommodated in the valve housing, and a hydraulic servo actuator for driving the poppet valve to be opened and closed. The hydraulic servo actuator is provided by a three-port or four-port servo valve.

Abstract: An EGR cooler includes: a casing in which cooling water flows; a plurality of tubes in which exhaust gas flows, the plurality of tubes being housed in the casing; a header plate to which ends of the plurality of tubes are bonded, the header plate being bonded to an end of the casing; an inlet tank into which the exhaust gas is introduced, the inlet tank being bonded to the end of the casing; and a shielding member being provided in the inlet tank to shield a circumferential wall of the inlet tank from the introduced exhaust gas.

Abstract: An EGR valve device includes a valve housing of which inside exhaust gas passes through, a poppet valve as a valve body accommodated in the valve housing, and a hydraulic servo actuator for driving the poppet valve to be opened and closed. The hydraulic servo actuator is provided by a three-port or four-port servo valve.

Abstract: A valve device includes a valve housing body having a passage for fluid, a valve guide formed in the valve housing body, a valve stem sliding in the valve guide for opening and closing the valve, a hydraulic actuator for opening and closing a valve, and a hydraulic control valve for controlling the hydraulic actuator, in which a scraper is provided on an end of the passage side of the valve guide for scraping the deposits on the valve stem. Further, the hydraulic actuator and the hydraulic control valve are integrated with the valve housing body. Furthermore, the device is provided with a nozzle oriented toward the valve guide and having an orifice for jetting pressured oil for cooling.

Abstract: A valve device includes a valve housing body having a passage for fluid, a valve guide formed in the valve housing body, a valve stem sliding in the valve guide for opening and closing the valve, a hydraulic actuator for opening and closing a valve, and a hydraulic control valve for controlling the hydraulic actuator, in which a scraper is provided on an end of the passage side of the valve guide for scraping the deposits on the valve stem. Further, the hydraulic actuator and the hydraulic control valve are integrated with the valve housing body. Furthermore, the device is provided with a nozzle oriented toward the valve guide and having an orifice for jetting pressured oil for cooling.