Abstract: A rotational angle sensor for an EGR valve memorizes a correlated characteristic between hall voltage and output voltage. Hall voltage of the rotational angle sensor at a reference angle is matched to a boundary value for the hall voltage on a valve closing side, wherein the reference angle is set at such an angle, which is shifted by a predetermined angle in the valve closing side from an upper-limit angle of a flow-rate dead zone. A valve full-closing control is carried out in order that the hall voltage will coincide with the boundary value on the valve closing side. An actual value of the rotational angle coincides with a value, which is shifted from the reference angle in a valve closing or opening direction by a changing range decided by changing factors of a sensor side and/or a mechanical-part side.

Abstract: An air intake device for an engine includes a duct having therein a first air flow passage, a housing having therein a second air flow passage, a rotary valve having a valve plate. A block of the housing, which conducts intake air to an intake port of a cylinder head, has a circular opposed surface that follows a shape of a curved surface portion of the valve plate. Moreover, the block of the housing has a protrusion that protrudes toward an upstream side of the second air flow passage in an air flow direction so as to contact a duct protrusion of the duct. Therefore, a localized flow of the intake air, which has flowed into the second air flow passage from an opening of the first air flow passage, can be restrained from spreading, and a flow rate of the localized flow can be restrained from slowing down.

Abstract: A control device for an engine variably controls electricity power supplied to a motor driving a valve to open or close a fluid passage based on operation condition of the engine. The valve has a full close range in which the fluid passage is closed. When the engine has low load and low rotation, the control device stops supplying the electricity power to the motor, and the valve is held at a neutral position where a biasing force of a first biasing portion and a biasing force of a second biasing portion are balanced. The neutral position is set within the full close range.

Abstract: An inner ring of a bearing is fixed to an outer periphery of a central portion of a shaft between a pair of facing sections. An outer ring of the bearing is fixed to a hole wall surface of a shaft accommodation recess. A spring is accommodated between one of the pair of facing sections and the bearing in a state where the spring is compressed in a rotational axis direction of a pin rod for pressing the bearing against the other one of the pair of facing sections. Thus, defects such as galling or friction between a casing and rotary valves can be inhibited. Accordingly, occurrence of wear or an abnormal noise between the casing and the rotary valves can be inhibited.

Abstract: When a valve body is rotated toward a full-close position in a valve-close mode, a control portion controls an electric motor so that the rotating speed of the valve body is lower than that in a valve-open mode. A rotating speed of the valve body around the shaft in the valve-close mode is lower than that in the valve-open mode. Thus, when the seal ring is brought into contact with the inner wall surface, an impact generated therebetween can be moderated. While the valve body is rotated toward the full-close position, a seal ring is gradually elastically deformed. A sliding friction between the seal ring and the inner wall surface can be reduced.

Abstract: An EGR valve includes an aluminum valve body, an outer metal ring, an inner resin ring, a butterfly valve, and a seal ring. The valve body includes a gas passage therein. The gas passage is part of an EGR passage, through which EGR gas is returned from an exhaust passage to intake passage of an engine. The outer ring has a cylindrical shape, and is fixed and disposed on an inner wall of the gas passage. The inner ring has a cylindrical shape, and is disposed on an inner peripheral wall of the outer ring. The butterfly valve opens or closes an inside of the inner ring, and includes a seal fitting groove at an outer peripheral edge of the butterfly valve. The seal ring is fitted into the groove, and seals a clearance between the butterfly valve and the inner ring when the butterfly valve is closed.

Abstract: An intake system for an engine includes a duct defining an intake passage therein, and a cantilevered valve including a valve main body opening/closing the intake passage, a shaft supporting the body, and a valve extension portion. The duct includes a reduced passage portion between the duct and the body when the body is in a fully closed position, a recess accommodating the body and the extension portion when the body is fully opened, and a pressure introduction passage formed between the duct and the body when the body is fully closed, and communicating with a space between the body and the extension portion when the body is fully closed. The extension portion includes a sealing part. The duct and the sealing part define a clearance therebetween when the body is fully closed. The clearance has a smaller sectional area than the reduced passage portion.

Abstract: An L-shaped rotary valve has a pair of side plates and a valve plate. The rotary valve is rotatably supported in a housing at a shaft 5. The valve plate moves along downstream ends of side wall portions of an air duct. A gap is formed between a downstream end of an air-intake passage and the valve plate, when the rotary valve is moved to its valve closed position. The side plates of the rotary valve cover the gap in a lateral direction in parallel to an axial direction of the shaft, so that leakage of air flow in the lateral direction of the gap is suppressed.

Abstract: An intake control device for an internal combustion engine includes an intake air induction duct, a housing, a valve, and a gasket. The housing is received in a receiving chamber of the intake air induction duct. The valve is received in the housing for opening and closing an intake passage defined in the housing. The gasket is mounted on one of (a) a position between the intake air induction duct and the attachment surface, and (b) a position between the housing and a wall surface of the receiving chamber. The housing opposes the attachment surface and is spaced from the attachment surface by a predetermined clearance. The gasket has an elastic deformation portion that is positioned between the housing and the attachment surface.

Abstract: A passage intake control device includes a passage member, a valve disposed in the passage member and a shaft passing through a through hole of a valve shaft part of the valve. The valve shaft part includes a fitting hole portion as a part of the through hole. The fitting hole portion is provided by at least a first wall, a second wall, a third wall and a fourth wall. The shaft includes a fitting part having a polygonal shape including at least a first shaft surface a second shaft surface, a third shaft surface and a fourth shaft surface. The fitting part is fitted in the fitting hole portion such that the first to fourth shaft surfaces are opposed to the first to fourth walls of the fitting hole portion, respectively. The first and second walls have protruded ribs. The third and fourth walls include flat portions.

Abstract: An inner ring of a bearing is fixed to an outer periphery of a central portion of a shaft between a pair of facing sections. An outer ring of the bearing is fixed to a hole wall surface of a shaft accommodation recess. A spring is accommodated between one of the pair of facing sections and the bearing in a state where the spring is compressed in a rotational axis direction of a pin rod for pressing the bearing against the other one of the pair of facing sections. Thus, defects such as galling or friction between a casing and rotary valves can be inhibited. Accordingly, occurrence of wear or an abnormal noise between the casing and the rotary valves can be inhibited.

Abstract: An intake controller includes a casing defining an intake passage that communicates with a combustion chamber of an engine, a valve received in the casing to open/close the passage, a rotational shaft that changes an opening degree of the valve, an actuator having a gear that drives the valve through the shaft, a gear retaining member retaining the gear, a sensor including a magnet that rotates according to rotation of the shaft and a magnetic detection element that detects magnetic flux generated from the magnet, and a sensor retaining member retaining the sensor. The sensor detects the opening degree of the valve based on a change of density of the magnetic flux passing through the element. One of the gear and the gear retaining member, and one of the sensor and the sensor retaining member are separately fixed on the shaft.

Abstract: An air intake device for an engine includes a duct having therein a first air flow passage, a housing having therein a second air flow passage, a rotary valve having a valve plate. A block of the housing, which conducts intake air to an intake port of a cylinder head, has a circular opposed surface that follows a shape of a curved surface portion of the valve plate. Moreover, the block of the housing has a protrusion that protrudes toward an upstream side of the second air flow passage in an air flow direction so as to contact a duct protrusion of the duct. Therefore, a localized flow of the intake air, which has flowed into the second air flow passage from an opening of the first air flow passage, can be restrained from spreading, and a flow rate of the localized flow can be restrained from slowing down.

Abstract: In a manufacturing method of a valve unit, which includes a valve having a rotatable shaft that is rotatably supported by a housing through a bearing to open and close a fluid passage defined in the housing, the housing and the valve are simultaneously molded in a mold assembly. The bearing is installed between the housing and the rotatable shaft during execution of the molding of the housing and the valve.

Abstract: An L-shaped rotary valve has a pair of side plates and a valve plate. The rotary valve is rotatably supported in a housing at a shaft 5. The valve plate moves along downstream ends of side wall portions of an air duct. A gap is formed between a downstream end of an air-intake passage and the valve plate, when the rotary valve is moved to its valve closed position. The side plates of the rotary valve cover the gap in a lateral direction in parallel to an axial direction of the shaft, so that leakage of air flow in the lateral direction of the gap is suppressed.

Abstract: An intake system for an engine includes a duct defining an intake passage therein, and a cantilevered valve including a valve main body opening/closing the intake passage, a shaft supporting the body, and a valve extension portion. The duct includes a reduced passage portion between the duct and the body when the body is in a fully closed position, a recess accommodating the body and the extension portion when the body is fully opened, and a pressure introduction passage formed between the duct and the body when the body is fully closed, and communicating with a space between the body and the extension portion when the body is fully closed. The extension portion includes a sealing part. The duct and the sealing part define a clearance therebetween when the body is fully closed. The clearance has a smaller sectional area than the reduced passage portion.

Abstract: In a manufacturing method of a valve unit, which includes a valve having a rotatable shaft that is rotatably supported by a housing through a bearing to open and close a fluid passage defined in the housing, the housing and the valve are simultaneously molded in a mold assembly. The bearing is installed between the housing and the rotatable shaft during execution of the molding of the housing and the valve.

Abstract: A passage intake control device includes a passage member, a valve disposed in the passage member and a shaft passing through a through hole of a valve shaft part of the valve. The valve shaft part includes a fitting hole portion as a part of the through hole. The fitting hole portion is provided by at least a first wall, a second wall, a third wall and a fourth wall. The shaft includes a fitting part having a polygonal shape including at least a first shaft surface a second shaft surface, a third shaft surface and a fourth shaft surface. The fitting part is fitted in the fitting hole portion such that the first to fourth shaft surfaces are opposed to the first to fourth walls of the fitting hole portion, respectively. The first and second walls have protruded ribs. The third and fourth walls include flat portions.

Abstract: An intake control device for an internal combustion engine includes an intake air induction duct, a housing, a valve, and a slope member. The intake air induction duct includes a bonding surface that is bonded with an attachment surface of the internal combustion engine, and the intake air induction duct defines therein a receiving chamber that opens at the bonding surface. The housing is received in the receiving chamber, and the housing defines therein an intake passage that is communicated with an intake port of the internal combustion engine. The valve is received in the housing for opening and closing the intake passage. The slope member cancels a step provided between the intake port and the intake passage.

Abstract: An intake control device for an internal combustion engine includes an intake air induction duct, a housing, a valve, and a gasket. The housing is received in a receiving chamber of the intake air induction duct. The valve is received in the housing for opening and closing an intake passage defined in the housing. The gasket is mounted on one of (a) a position between the intake air induction duct and the attachment surface, and (b) a position between the housing and a wall surface of the receiving chamber. The housing opposes the attachment surface and is spaced from the attachment surface by a predetermined clearance The gasket has an elastic deformation portion that is positioned between the housing and the attachment surface.