JP2010084749A - Exhaust gas recirculation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the degradation of a EGR gas recirculation amount (an EGR amount) and engine output by reducing flow path resistance in an EGR gas passage of a housing. <P>SOLUTION: In an EGR valve module incorporated in this exhaust gas recirculation device (an EGR system), a first inlet pipe 21 in the housing 1 connected to the downstream end of an EGR pipe is connected in acute-angle inclination (V-shaped connection) to part of the intake duct of an engine (a second inlet pipe 22, a base 23 and an outlet pipe 24). Namely, the combination angle between the EGR gas passage 11 formed in the first inlet pipe 21 and an air introduction passage 12 formed in the second inlet pipe 22 is set to be smaller than 90°(an acute angle). This reduces flow path resistance resulting from the curve of the EGR gas passage 11 at its downstream position to prevent the degradation of an EGR amount and engine output. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an exhaust gas recirculation device (EGR system) in which two first and second valves (EGR valve, throttle valve) are arranged on the same axis in the rotation axis direction of a common shaft.

[Conventional technology]
Conventionally, a part of exhaust gas is used for the purpose of reducing harmful substances (for example, nitrogen oxides: NOx, etc.) contained in exhaust gas discharged from a combustion chamber of an internal combustion engine (engine) such as a diesel engine. An exhaust gas recirculation device (EGR system) provided with an exhaust gas recirculation pipe (EGR pipe) for recirculating EGR gas as described above from the exhaust passage to the intake passage is known.
This EGR device includes an exhaust gas flow rate control valve (EGR gas flow rate control valve) that variably controls the flow rate (EGR amount) of EGR gas flowing in the exhaust gas recirculation pipe (exhaust gas passage: hereinafter referred to as EGR gas passage). Is incorporated.

The EGR gas flow control valve includes a housing in which an EGR gas passage is formed, a valve shaft rotatably supported by a shaft bearing portion of the housing, an EGR valve held and fixed to the valve shaft, and a valve shaft. It is comprised by the electric motor etc. which rotationally drive an EGR valve.
Recently, due to the desire to further improve the exhaust gas performance by putting a large amount of EGR gas into the intake port of the engine, when the EGR valve is opened, a new intake air is introduced so that the flow rate of the new intake air is reduced. An intake throttle (throttle valve) that adjusts the flow rate of air is used. Further, as an actuator for controlling the opening / closing of the throttle valve, a direct current (DC) motor having a good control response is generally used to prevent smoke during acceleration.

On the other hand, in vehicles such as automobiles, the engine intake system is released again without releasing the gas (blow-by gas: hereinafter referred to as PCV gas) that blows into the crankcase from the gap between the piston and cylinder of the engine. A blow-by gas reduction device (PCV device) for returning to the combustion chamber and re-combusting is mounted.
This PCV device extracts the PCV gas generated inside the crankcase, returns it to the intake system of the engine for recombustion, and introduces clean outside air filtered by an air cleaner into the crankcase to ventilate the crankcase. Like to do.
Therefore, the PCV device introduces air into the engine head cover or crankcase from the intake passage upstream of the throttle valve, and returns the PCV gas generated inside the crankcase to the intake passage downstream of the throttle valve. is doing.

Here, FIG. 12 is a view showing the junction 103 between the intake passage 101 and the PCV passage 102. In the intake passage 101, a throttle valve (valve of an electronic throttle device) 104 for controlling the flow rate of intake air sucked into the combustion chamber of the engine is housed so as to be freely opened and closed. The PCV passage 102 accommodates a PCV valve (PCV device valve) 105 that controls the flow rate of the PCV gas discharged to the intake passage 101 so as to be freely opened and closed.
The electric motor 106 that rotationally drives the throttle valve 104 and the PCV valve 105 includes a valve shaft (rotating shaft) 107 that coaxially arranges the throttle valve 104 and the PCV valve 105. In response to the above, the respective flow rates are changed simultaneously (see, for example, Patent Document 1).
Here, a structure in which the PCV valve 105 in FIG. 12 is changed to an EGR valve and the throttle valve 104 and the EGR valve are arranged on the same axis line in the rotation axis direction of the common valve shaft 107 can be considered.

[Conventional technical problems]
However, in the EGR device having a structure in which the throttle valve 104 and the EGR valve are arranged on the same axis in the rotation axis direction of the common valve shaft 107, the EGR gas passage is bent at a right angle before the junction 103. Since it is configured to be connected to the merging portion 103, the EGR gas flow path resistance increases due to the bending of the EGR gas passage, causing a problem that the EGR amount is reduced and the engine output is reduced. . The EGR gas flow resistance is a ventilation resistance received by the EGR gas when the EGR gas flows through the exhaust gas recirculation pipe or the EGR gas passage.

Further, the throttle valve 104 shown in FIG. 12 is set to the fully open position in the initial state. When the supply of electric power to the electric motor 106 is started and the valve shaft 107 is rotated, the valve angle of the throttle valve 104 gradually increases as the valve shaft 107 rotates, and conversely the flow rate of the intake air Gradually decreases. That is, when the valve angle of the throttle valve 104 is increased, the throttle opening is decreased, and the intake resistance in the intake passage 101 is increased. As a result, there is a problem that the fuel consumption is deteriorated by the increase in the intake resistance in the intake passage 101 when the valve angle range (for example, 0 to 30 deg) used during normal running of a vehicle such as an automobile is increased.
JP 2007-092664 A

  An object of the present invention is to provide an exhaust gas recirculation device capable of reducing a flow resistance in an exhaust gas passage and preventing a decrease in the amount of exhaust gas recirculated to the intake port of the internal combustion engine and a decrease in output of the internal combustion engine. There is to do. Another object of the present invention is to provide an exhaust gas recirculation device that can reduce the intake resistance in the intake air passage during the valve angle range used during normal running of the vehicle and prevent deterioration of fuel consumption.

According to the first aspect of the present invention, the flow resistance (exhaust gas ventilation resistance) in the exhaust gas passage is set by setting the merging angle between the exhaust gas passage and the intake air passage to an angle smaller than 90 degrees. Can be reduced. As a result, it is possible to prevent a reduction in the amount of exhaust gas recirculated to the intake port of the internal combustion engine and a reduction in the output of the internal combustion engine.
Further, since the first valve and the second valve are arranged on the same axis in the rotation axis direction of the common shaft, the physique of the entire apparatus can be reduced in size. This makes it easy to secure a mounting space. In addition, since the actuators that drive the two first and second valves are shared and the shaft is shared, the number of parts can be reduced and the cost can be reduced.

According to the second aspect of the present invention, the two first and second valves are fixed to the shaft. One of the two first and second valves is fixed to a central portion in the axial direction of the shaft. The other second valve of the two first and second valves is fixed to an end portion on the opposite side to the actuator side in the axial direction of the shaft.
According to invention of Claim 3, a 2nd valve | bulb is the axial direction part extended in the axial direction of a shaft, and the both sides of the orthogonal | vertical direction orthogonal to the axial direction of an axial direction part on the boundary of this axial direction part. A plate-shaped valve main body extending in the direction of.

According to the invention described in claim 4, the valve body of the second valve has the side cut portion on one side in the vertical direction orthogonal to the axial direction of the axial direction portion of the second valve. As a result, even if the shaft is rotated in the valve closing operation direction from the valve fully open position by the driving force of the actuator, the intake air passage on the upstream side of the second valve is within the range from the valve fully open position to the predetermined rotation angle. When the second valve is viewed, the amount of protrusion of the valve body from the axial portion of the second valve is reduced, and the valve body is hidden by the axial portion of the second valve, that is, suction near the second valve fully opened position. A dead zone in which the air flow rate does not change is formed.
As a result, in the range from the fully open position of the valve to the predetermined rotation angle, the intake air passage (confluence section) passes from the intake air passage upstream of the second valve to the periphery of the second valve and downstream of the second valve. The intake air flow toward (including) the air flow is less likely to be disturbed, and it is easy to smoothly flow along the shape of the axial portion of the second valve. Therefore, since the intake resistance in the intake air passage when the valve angle range (for example, 0 to 30 deg) used during normal running of the vehicle can be reduced, deterioration of fuel consumption can be prevented.

According to invention of Claim 5, the shaft has the valve | bulb holding | maintenance part which fixes the axial direction part of a 2nd valve | bulb. By making the outer diameter of the valve holding portion at least larger than the thickness of the valve body in the plate thickness direction, even if the shaft rotates in the valve closing operation direction from the valve fully open position by the driving force of the actuator, the valve fully open position When the second valve is viewed from the intake air passage on the upstream side of the second valve, the valve body is hidden by the shaft holding portion of the shaft and the axial portion of the second valve. In other words, a dead zone in which the flow rate of the intake air in the vicinity of the fully opened position of the second valve does not change is formed.
As a result, in the range from the fully open position of the valve to the predetermined rotation angle, the intake air passage (confluence section) passes from the intake air passage upstream of the second valve to the periphery of the second valve and downstream of the second valve. The intake air flow toward the gas flow smoothly flows along the shapes of the valve holding portion of the shaft and the axial portion of the second valve without being disturbed. Therefore, since the intake resistance in the intake air passage when the valve angle range (for example, 0 to 30 deg) used during normal running of the vehicle can be reduced, deterioration of fuel consumption can be prevented.

According to invention of Claim 6, the 2nd valve | bulb has a pair of latching claw cut and raised according to the width | variety of a shaft. Thereby, after incorporating a shaft in the inside of a housing, a 2nd valve | bulb can be fixed to a shaft by crimping a pair of latching claw provided in the 2nd valve | bulb. Therefore, even if the axial direction of the shaft is installed obliquely with respect to the axial direction (flow path direction) of the intake air passage, the second valve for the shaft incorporated (inserted) inside the housing Assembling becomes easy.
According to the invention described in claim 7, the shaft is rotatably supported by the housing via the bearing member fixed to the housing.
According to the eighth aspect of the present invention, the elastic member capable of elastic deformation is mounted between the outer periphery of the shaft and the inner periphery of the bearing member.
Thereby, the assembly clearance between the outer periphery of the shaft and the inner periphery of the bearing member is absorbed by the elastic member.
Here, the first valve is a butterfly type EGR valve that controls the flow rate of the exhaust gas recirculated from the exhaust gas passage to the intake air passage according to the rotation angle of the shaft. The second valve is a butterfly throttle valve that controls the flow rate of the intake air to the internal combustion engine in accordance with the rotation angle of the shaft.

The best mode for carrying out the present invention aims to reduce the flow resistance in the exhaust gas passage and prevent a reduction in the amount of exhaust gas recirculated to the intake port of the internal combustion engine and a reduction in the output of the internal combustion engine. The merging angle between the exhaust gas passage and the intake air passage is set to an angle smaller than 90 degrees, that is, the exhaust gas recirculation pipe (EGR pipe) of the internal combustion engine and the intake pipe (intake duct) of the internal combustion engine are V-shaped. Realized by connecting in a shape.
The purpose of the present invention is to reduce the intake resistance in the intake air passage during the valve angle range used during normal running of the vehicle to prevent the deterioration of fuel consumption, and the axial direction of the second valve of the valve body of the second valve This was realized by providing a side cut portion on one side of the vertical direction orthogonal to the axial direction of the portion. Further, the outer diameter of the valve holding portion of the shaft is realized by making it larger than at least the thickness of the valve body in the plate thickness direction of the second valve.

[Configuration of Example 1]
FIGS. 1 to 7 show Embodiment 1 of the present invention. FIG. 1 shows an EGR valve module incorporated in an exhaust gas recirculation device (EGR system) of an internal combustion engine. FIG. 2 shows a first bearing. 3 (a) is a view showing a fully closed state of the throttle valve, FIG. 3 (b) is a view showing a fully opened state of the throttle valve, FIG. 4 (a), (B) is the figure which showed the assembly | attachment structure of the throttle valve to a valve shaft.

An exhaust gas recirculation device (EGR system) for an internal combustion engine according to the present embodiment converts EGR gas (exhaust recirculation gas), which is a part of exhaust gas of an internal combustion engine (hereinafter referred to as an engine) such as a diesel engine, into each engine. An exhaust gas recirculation pipe (EGR pipe) that recirculates to an intake port for each cylinder and an EGR valve module installed at a connection portion between the EGR pipe and the engine intake pipe are provided.
Here, a direct injection diesel engine in which fuel is directly injected into the combustion chamber is employed as the engine. An intake passage (intake passage of the internal combustion engine) formed in the engine intake pipe (intake duct) is connected to an intake port for each cylinder of the engine. Further, an exhaust passage (exhaust passage of the internal combustion engine) formed in the engine exhaust pipe (exhaust duct) is connected to an exhaust port for each cylinder of the engine.

  The EGR valve module includes an exhaust gas flow rate control valve (EGR gas flow rate control valve: hereinafter referred to as EGRV) that controls the flow rate of EGR gas flowing through an exhaust gas passage (EGR gas passage) 11 formed inside the housing 1; An intake air flow rate control valve (electronic throttle device) that controls the flow rate of new intake air that flows through an intake air passage (air introduction passage) 12 formed inside the housing 1 is combined and integrated. This EGR valve module includes a common housing 1 for the EGRV and the electronic throttle device.

The housing 1 is formed in a predetermined shape by, for example, a heat-resistant material (for example, iron-based casting, cast iron), a heat-resistant aluminum alloy die-cast, or an aluminum alloy-based casting having excellent high-temperature heat resistance. The housing 1 is provided with a cylindrical nozzle fitting portion that fits and holds a cylindrical nozzle (cylindrical portion) 2.
Further, inside the housing 1, EGR gas passage 11 into which EGR gas is introduced via the EGR gas passage in the EGR pipe, and new intake air filtered by the air cleaner pass through the intake passage in the upstream intake duct. An air introduction passage (intake passage of the internal combustion engine) 12 introduced via, an merging portion of the EGR gas passage 11 and the air introduction passage 12 (intake passage of the internal combustion engine, mixing chamber: hereinafter referred to as a merging chamber) 13, and An air outlet passage (intake passage of the internal combustion engine) 14 is formed to allow the intake air to flow out from the junction chamber 13 toward the intake port side of the engine.
The housing 1 also has a bearing holding portion (block) 16 in which a shaft through hole 15 is formed.
Details of the housing 1 will be described later.

The EGRV is installed (mounted) in the housing 1 and is inserted into the nozzle 2 fitted and held in the housing 1 to open and close the EGR gas passage 11 (first butterfly type valve (exhaust gas flow control valve: hereinafter). (Referred to as an EGR valve) 3, a valve shaft 5 that supports the EGR valve 3, and an actuator body 9 that drives the EGR valve 3 via the valve shaft 5.
The electronic throttle device is installed (mounted) in the same housing 1 as the EGRV, and the throttle valve 4 that is inserted into the housing 1 to open and close the air introduction passage 12, and the EGR valve 3 and the throttle valve 4 are coaxial. And the actuator body 9 for driving the throttle valve 4 via the valve shaft 5.

The EGR valve 3 of the present embodiment is formed in a disk shape from a heat resistant material resistant to high temperatures, for example, a metal material such as stainless steel. The EGR valve 3 is housed in a nozzle 2 fitted in a nozzle fitting portion of the housing 1 so as to be freely opened and closed. Then, the EGR valve 3 is configured so that the opening angle of the EGR gas passage 11 of the housing 1 is continuously variably adjusted by changing the rotation angle about the rotation axis of the valve shaft 5, so that the intake passage is changed from the exhaust passage to the intake passage. The flow rate of the EGR gas recirculated (EGR amount: EGR rate with respect to the new intake air amount) is arbitrarily variably controlled.
The EGR valve 3 rotates in the valve operating range from the valve fully closed position to the valve fully open position (changes the rotation angle) based on a control signal from an engine control unit (hereinafter referred to as ECU) during engine operation. ), The opening area (EGR gas distribution area) of the EGR gas passage 11 is changed to variably control the EGR amount.
The EGR valve 3 is accommodated in the nozzle 2 fitted and held in the housing 1 so as to be freely opened and closed. The EGR valve 3 is held and fixed at an intermediate position in the rotation axis direction of the valve shaft 5 in a state inclined by a predetermined inclination angle with respect to the rotation axis direction (shaft axis direction) of the valve shaft 5.

In addition, an annular seal ring groove extending in the valve circumferential direction is formed on the entire outer peripheral end surface of the EGR valve 3. A C-shaped seal ring that can be brought into close contact with the inner diameter surface of the nozzle 2 is fitted into the seal ring groove. The seal ring has a seal ring groove so that the inner diameter side end can move in the radial direction, the axial direction and the valve circumferential direction in a state where the outer diameter side end protrudes from the outer peripheral end surface of the EGR valve 3. It is fitted inside.
Therefore, in the EGR valve module of the present embodiment, when the EGR valve 3 is stopped at the fully closed position, that is, the EGR valve 3 is set in the vertical direction perpendicular to the flow direction of the EGR gas passage 11. When the EGR valve 3 is fully closed, the inner diameter surface of the nozzle 2 and the outer peripheral end surface of the EGR valve 3 are utilized by utilizing the tension in the radial direction (expansion direction) of the seal ring fitted in the seal ring groove. It is comprised so that the clearance gap between may be sealed (sealed).
Details of the EGR valve 3 will be described later.

The throttle valve 4 of the present embodiment is formed in a predetermined shape from a synthetic resin material. The throttle valve 4 is housed inside the housing 1 so as to be opened and closed. The throttle valve 4 is variably adjusted by continuously changing the opening angle of the air introduction passage 12 of the housing 1 by changing the rotation angle about the rotation axis of the valve shaft 5, so that new intake of EGR gas is performed. The flow rate of air is variably controlled.
The throttle valve 4 rotates (changes the rotation angle) in the valve operating range from the valve fully open position to the valve fully closed position based on a control signal from the ECU during engine operation. The flow rate of the new intake air is variably controlled by changing the opening area of 12 (new intake air flow area).

The throttle valve 4 is disposed on a valve shaft 5 as a shaft member with a predetermined angle with respect to the EGR valve 3. That is, the EGR valve 3 and the throttle valve 4 are disposed coaxially with the valve shaft 5.
After the valve shaft 5 is assembled to the housing 1, the throttle valve 4 is held and fixed at the distal end portion of the valve shaft 5 in the shaft axial direction in the air introduction passage 12. Here, the tip end side of the valve shaft 5 in the shaft axial direction (the portion where the throttle valve 4 is mounted) is inserted into the housing 1 so as to be inclined with respect to a vertical line perpendicular to the flow direction of the air introduction passage 12. Has been. For this reason, the rotational axis direction of the throttle valve 4 is also inclined with respect to a vertical line perpendicular to the flow direction of the air introduction passage 12.
The details of the throttle valve 4 will be described later.

The valve shaft 5 is formed in a cylindrical shape from a heat-resistant material (for example, a metal material such as stainless steel or heat-resistant steel) excellent in high-temperature heat resistance, and has two first and second bearings (first and second bearing members). ) 6 and 7 are rotatably supported with respect to the housing 1. The valve shaft 5 is formed straight in the rotation axis direction from one end side to the other end side. Further, the valve shaft 5 is inserted from the inside of the actuator main body 9 into the air introduction passage 12 of the housing 1 through the EGR gas passage 11 of the housing 1 and the shaft through hole 15 of the block 16.
Then, one end of the valve shaft 5 is connected to a final reduction gear, which will be described later, and the EGR valve 3 is fastened (fastened) to the central portion (actuator side) of the rotary shaft using a screw 17. A second valve that has a first valve mounting portion (first valve holding portion), and that fixes the throttle valve 4 by caulking to the end portion (the other end side, the tip end side) opposite to the actuator side in the rotation axis direction A mounting portion (second valve holding portion) 18 is provided.

A fastening hole into which the screw 17 is screwed is formed in the first valve mounting portion of the valve shaft 5. The second valve mounting portion 18 of the valve shaft 5 is formed with an engagement groove (planar portion) 19 for positioning the throttle valve 4 with respect to the rotation axis direction of the valve shaft 5.
The two first and second bearings 6 and 7 include an inner ring fixed to the outer peripheral side of the valve shaft 5, an outer ring press-fitted and fixed to the block side of the housing 1 and the housing side of the actuator body 9, and an inner ring and an outer ring A plurality of steel balls that are slidably accommodated between the two race rings and roll between the race surface of the inner ring and the race surface of the outer ring. A ball bearing that supports the outer diameter portion of the valve shaft 5 so as to be slidable in the rotational direction by rolling friction is employed.
Of the two first and second bearings 6 and 7, the outer ring of the first bearing 6 installed on the side close to the tip of the valve shaft 5 is press-fitted and fixed to the hole wall surface of the shaft through hole 15 of the housing 1. ing. An elastic member 8 such as an O-ring is mounted between the inner circumference of the inner ring of the first bearing 6 and the outer circumference groove of the valve shaft 5.

The actuator body 9 is a housing whose opening is closed by the sensor cover 10. The actuator body 9 is a die-cast product made of an aluminum alloy, and is clamped (fastened) to the actuator mounting surface of the housing 1 using a plurality of fastening bolts.
In addition, the actuator body 9 is supplied with electric power, and receives an electric motor (for example, a DC motor) that generates driving force for driving the EGR valve 3 and the throttle valve 4, and the driving force of the electric motor is supplied to the valve shaft. A power transmission mechanism (for example, a gear speed reduction mechanism) for transmitting to 5 is incorporated. An oil seal and a second bearing 7 are fitted and held between the valve shaft 5 and the bearing portion of the actuator body 9.
The gear reduction mechanism includes a motor gear (pinion gear) fixed to the motor shaft of the electric motor, an intermediate reduction gear that meshes with the pinion gear, a final reduction gear (valve gear) that meshes with the intermediate reduction gear, and the like. A coil spring is installed in the actuator body 9 so as to surround the periphery of the valve shaft 5 in the circumferential direction. This coil spring (return spring, default spring) urges the EGR valve 3 in the valve closing operation direction and the throttle valve 4 in the valve opening operation direction.

The actuator body 9 also converts the rotation angle (valve opening) of the EGR valve 3 and the throttle valve 4 into an electrical signal, and outputs to the ECU how much the EGR valve 3 and the throttle valve 4 are open. A flow sensor is installed. That is, not only the actuator body 9 but also an EGR gas flow sensor is mounted on the housing 1 of the EGR valve module.
Here, the electric motor which is a power source of the actuator body 9 is configured to be energized and controlled by the ECU.
The ECU has a known structure that includes functions of a CPU that performs control processing, arithmetic processing, a storage device (memory such as ROM and RAM) that stores various programs and various data, an input circuit, and an output circuit. A microcomputer is provided.

In addition, when the ignition switch (not shown) is turned on (IG / ON), the ECU sets the valve opening (valve opening) of the EGR valve 3 and the throttle valve 4 based on a control program stored in the memory of the microcomputer. It is configured to be electronically controlled. The ECU is configured to forcibly terminate the above control based on the control program stored in the memory when the ignition switch is turned off (IG / OFF).
The sensor signals from the various sensors are A / D converted by an A / D converter and then input to a microcomputer built in the ECU. The microcomputer is connected to a crank angle sensor, an accelerator opening sensor, an air flow meter, a cooling water temperature sensor, an EGR gas flow rate sensor, and the like.
The EGR gas flow rate sensor is held and fixed to a sensor holding portion provided inside the sensor cover 10.

Next, details of the housing 1 of the present embodiment will be described with reference to FIGS.
The housing 1 is a three-way pipe including a base (cylindrical portion) 23 that is connected to the downstream end of the EGR pipe and in the middle of the intake duct, and in which a merging chamber 13 is formed. The housing 1 includes a cylindrical first inlet pipe 21 projecting upstream of the base 23 in the EGR gas flow direction (exhaust passage side), and an upstream side of the new intake air flow direction (air cleaner side) of the base 23. A cylindrical second inlet pipe 22 projecting inward, and a cylindrical outlet pipe 24 projecting downstream (surge tank side or intake manifold side) in the EGR gas flow direction (new intake air flow direction) from the base 23; Are integrally formed.

Here, an EGR gas passage 11 is formed inside the first inlet pipe 21. An air introduction passage 12 is formed inside the second inlet pipe 22. An air outlet passage 14 is formed in the outlet pipe 24. The two first and second inlet pipes 21 and 22 are connected by a block 16 having a shaft through hole 15 formed therein.
The first inlet pipe 21 has a smaller inner diameter than the second inlet pipe 22, the base 23, and the outlet pipe 24 that form a part of the intake duct of the engine, and is smaller than the second inlet pipe 22, the base 23, and the outlet pipe 24. It is connected at an acute angle (V-shaped connection). That is, in the EGR valve module of the present embodiment, the merging angle between the EGR gas passage 11 formed in the first inlet pipe 21 and the air introduction passage 12 formed in the second inlet pipe 22 is more than 90 degrees. A small angle (acute angle) is set.

The first inlet pipe 21 has a flange-shaped first flange portion 25 attached to a coupling end surface provided at the downstream end of the EGR pipe. An actuator mounting portion 26 for mounting the actuator body 9 is provided on the outer peripheral surface of the first inlet pipe 21.
The second inlet pipe 22 has a flange-like second flange portion 27 attached to a coupling end surface provided at the downstream end of the intake duct on the air cleaner side.
One outlet pipe 24 has a flange-like flange portion 28 attached to a coupling end surface provided at an upstream end of an intake duct (surge tank or intake manifold) on the intake port side of the engine.
The EGR gas passage 11 is inclined with respect to an axis (center axis of the intake passage) passing through the centers of the air introduction passage 12, the merging chamber 13, and the air outlet passage 14 and extends straightly (exhaust gas passage). Configure.
The air introduction passage 12, the merging chamber 13, and the air lead-out passage 14 constitute a straight passage (intake passage) that extends straightly along the central axis of the intake passage.
The housing 1 is made of a metal material such as stainless steel having excellent heat resistance and corrosion resistance only on the sliding portion near the valve fully closed position where the seal ring mounted on the outer peripheral end face of the EGR valve 3 is in sliding contact. The cylindrical nozzle 2 formed by the above is press-fitted and fixed to the inner wall surface of the nozzle fitting portion of the first inlet pipe 21.

Next, details of the EGR valve 3 of this embodiment will be described with reference to FIG.
The EGR valve 3 includes a cylindrical axial portion (shaft portion, thick portion) extending in the rotational axis direction of the first valve mounting portion of the valve shaft 5, and the axial direction of the axial portion with this axial portion as a boundary. It has a disk-shaped (plate-shaped) valve body (valve portion) extending on both sides in the vertical direction perpendicular to the vertical direction. These axial portions and the valve body are manufactured by press-molding a metal plate having a predetermined plate thickness. When the axial part and the valve body are manufactured separately, they are integrated by welding the axial part and the valve body with a laser welding device or the like.
The EGR valve 3 is held and fixed at an intermediate position (central portion) of the valve shaft 5 in the rotation axis direction in the EGR gas passage 11 after the valve shaft 5 is assembled in the EGR gas passage 11 of the housing 1. That is, the EGR valve 3 is formed with a shaft through-hole through which the first valve mounting portion of the valve shaft 5 passes. When the valve shaft 5 is assembled inside the housing 1, the valve shaft 5 is mounted by a jig or the like. The EGR gas passage 11 is passed through a shaft through hole of the EGR valve 3 held in the EGR gas passage 11. Then, after incorporating the valve shaft 5 into the EGR gas passage 11 of the housing 1, the EGR valve 3 is fastened and fixed to the first valve mounting portion of the valve shaft 5 using the screw 17.

Next, details of the throttle valve 4 of the present embodiment will be described with reference to FIGS. 1 and 3 to 6. Here, FIG. 5A is a view showing a method of assembling the throttle valve to the valve shaft, FIG. 5B is a view showing the throttle valve, and FIG. 5C is a second valve of the valve shaft. FIGS. 6A to 6C are diagrams illustrating the periphery of the mounting portion, and FIGS. 6A to 6C are diagrams illustrating the dead zone of the throttle valve. 6 (a) and 6 (b) are operational explanations showing a throttle valve having a larger outer diameter in the axial direction portion than the plate thickness of the two first and second valve bodies and having no side cut portion. FIG. 6C is an operation explanatory view showing a throttle valve having a side cut portion in which the outer diameter of the axial portion is larger than the plate thickness of the two first and second valve bodies.
The throttle valve 4 has an axial portion (shaft portion) 30 extending in the rotational axis direction of the second valve mounting portion 18 of the valve shaft 5 and the axial direction of the axial portion 30 with the axial portion 30 as a boundary. The first and second valve main bodies (valve portions) 31 and 32 having flat plate shapes (plate shapes) extending on both sides in the perpendicular direction perpendicular to each other are provided. The axial portion 30 and the two first and second valve bodies 31 and 32 are manufactured by press-molding a metal plate having a predetermined thickness.

  The axial portion 30 of the throttle valve 4 is a flat plate-shaped portion 33 that is fitted into an engagement groove 19 provided in the second valve mounting portion 18 of the valve shaft 5 and is engaged with both groove side surfaces of the engagement groove 19. And arcuate curved portions 34 and 35 bent so as to be curved along the convex curved surface (outer peripheral surface) of the second valve mounting portion 18 of the valve shaft 5 from both sides of the flat portion 33 in the plate width direction. Is formed. In addition, a pair of first and second parts that are cut and raised in accordance with the width of the valve shaft 5 are formed at lower end portions of the curved portions 34 and 35 (the root portions of the two first and second valve bodies 31 and 32). Locking claws 36 and 37 are formed.

On both sides of the two first and second valve bodies 31 and 32 in the vertical direction perpendicular to the rotation axis direction, the wall surface (inner peripheral surface) of the air introduction passage 12 of the housing 1 when the throttle valve 4 is fully closed. First and second side cut portions 38 and 39 that form a gap of a predetermined distance are formed. These two first and second side cut portions 38 and 39 are flat portions formed by cutting the arc-shaped outer peripheral end surfaces of the two first and second valve bodies 31 and 32.
The outer diameters of the axial portion 30 of the throttle valve 4 and the second valve mounting portion 18 of the valve shaft 5 are larger than the thickness of at least two first and second valve bodies 31 and 32 in the plate thickness direction. Yes.

  The throttle valve 4 is held and fixed at the distal end side in the rotational axis direction of the valve shaft 5 in the air introduction passage 12 after the valve shaft 5 is assembled in the air introduction passage 12 of the housing 1. That is, an axial portion 30 that engages with the second valve mounting portion 18 of the valve shaft 5 is formed between the first and second valve bodies 31 and 32 of the throttle valve 4. A pair of first and second locking claws 36, 37 are cut and raised at the lower end of the curved portions 34, 35 in accordance with the width of the valve shaft 5, and the valve shaft 5 is connected to the air introduction passage 12 of the housing 1. After being assembled in the inside, the flat portion 33 of the axial direction portion 30 of the throttle valve 4 is fitted and positioned in the engagement groove 19 formed in the second valve mounting portion 18 of the valve shaft 5, and is fixed by a caulking jig or the like. The throttle valve 4 is valved so as to embrace the convex curved surface (arc-shaped outer peripheral surface) of the second valve mounting portion 18 of the valve shaft 5 by caulking the pair of first and second locking claws 36, 37. It is caulked (coupled) to the second valve attachment portion 18 of the shift 5.

[Operation of Example 1]
Next, the operation of the EGR valve module incorporated in the EGR system of this embodiment will be briefly described with reference to FIGS.

The ECU supplies the electric power supplied to the electric motor built in the actuator body 9 corresponding to the engine operating state (engine information) such as the engine rotation speed, the accelerator opening, and the coolant temperature calculated based on the crank angle. The valve opening (rotation angle) of the EGR valve 3 and the valve opening (rotation angle) of the throttle valve 4 are adjusted.
Specifically, the valve opening (actual EGR amount, actual opening) detected by the EGR gas flow rate sensor substantially matches the control target value (target EGR amount, target opening) set corresponding to the engine information. Thus, feedback control is performed on the power supplied to the electric motor.
When the engine is running at low speed and low load, such as when the engine is idling, the amount of fuel injected into each cylinder of the engine is small, so the exhaust gas temperature is low, the intake negative pressure is low, and the exhaust gas pressure is also low. Since it is low, it is difficult for EGR gas to flow into the intake port of each cylinder of the engine. In such a case, as shown in FIG. 3A, the throttle valve 4 is set to the valve fully closed position, and the EGR valve 3 is set to the valve fully open position, thereby suppressing the inflow of new intake air. This facilitates the inflow of EGR gas.
When the throttle valve 4 is set to the valve fully closed position, the first and second first and second valve bodies provided on the passage wall surface of the air introduction passage 12 of the housing 1 and the outer diameter side ends of the first and second valve bodies 31 and 32 are provided. A small amount of new intake air flows into the intake port of each cylinder of the engine through a gap formed between the two side cut portions 38 and 39.

Here, when electric power is supplied to the electric motor, the motor shaft of the electric motor rotates. Thereby, the driving force (motor output shaft torque) of the electric motor is transmitted to the pinion gear, the intermediate reduction gear, and the final reduction gear. As the final reduction gear rotates, the valve shaft 5 rotates by a predetermined rotation angle, and the EGR valve 3 is driven to open from the fully closed position in the valve opening operation direction. At this time, the throttle valve 4 is driven to close in the valve closing operation direction from the valve fully opened position.
Accordingly, the EGR valve 3 is controlled to be opened to a valve opening corresponding to the control target value. As a result, a part of the exhaust gas flowing out from the combustion chamber of each cylinder of the engine (for example, high temperature EGR gas of 500 ° C. or more) is formed in the EGR pipe on the exhaust passage side from the exhaust passage formed in the exhaust pipe. The EGR gas passage and the EGR gas passage 11 in the first inlet pipe 21 of the housing 1 are recirculated to the merging chamber 13 in the base 23 of the housing 1 and the air outlet passage 14 in the outlet pipe 24 of the housing 1 ( Reflux).
As a result, EGR gas is mixed into the new intake air flowing through the merge chamber 13 in the base 23 of the housing 1 and the air outlet passage 14 in the outlet pipe 24 of the housing 1 and is sucked into the combustion chamber of each cylinder of the engine. Therefore, the maximum combustion temperature is lowered, and harmful substances (for example, nitrogen oxides: NOx, etc.) contained in the exhaust gas can be reduced.

On the other hand, at the time of high speed rotation and high load of an engine that requires high output, as shown in FIG. 3B, the throttle valve 4 is fully opened, the EGR valve 3 is fully closed, and the EGR gas is returned to the intake passage. I won't let you. As a result, only new intake air in which EGR gas is not mixed is sent to the combustion chamber for each cylinder of the engine, so that high output can be obtained.
When the EGR valve 3 is fully closed, the supply of electric power to the electric motor is stopped or the supply of electric power to the electric motor is restricted. Therefore, the urging force (spring load) of the coil spring built in the actuator body 9 rotates the valve shaft 5 to return the EGR valve 3 to the valve fully closed position and the throttle valve 4 to the valve fully open position.
As a result, the sliding surface of the seal ring mounted on the outer peripheral end surface of the EGR valve 3 sticks to the inner diameter surface of the nozzle 2 due to the tension in the diameter increasing direction of the seal ring itself. Close contact with the inner surface.
Therefore, the gap between the inner diameter surface of the nozzle 2 and the outer peripheral end surface of the EGR valve 3 is completely sealed. As a result, when the EGR valve 3 is held and fixed in the valve fully closed position (when the valve is fully closed), the leakage of EGR gas is reliably suppressed, so that the EGR gas does not enter the new intake air.

  Here, as described above, the throttle valve 4 includes the first and second side cut portions 38 and 39 on both sides in the vertical direction orthogonal to the rotation axis direction of the two first and second valve bodies 31 and 32. have. Further, the outer diameters of the axial portion 30 of the throttle valve 4 and the second valve mounting portion 18 of the valve shaft 5 are made larger than the thicknesses of at least two first and second valve bodies 31 and 32 in the plate thickness direction. Thus, even if the valve shaft 5 rotates in the valve closing operation direction from the valve fully open position by the driving force of the actuator body 9, the intake passage on the upstream side of the throttle valve 4 in the range from the valve fully open position to a predetermined rotation angle. When the throttle valve 4 is viewed from the axial direction portion 30 of the throttle valve 4 and the amount of protrusion of the first and second valve bodies 31 and 32 from the second valve mounting portion 18 of the valve shaft 5 is reduced, the throttle valve 4 A state in which the first and second valve bodies 31, 32 are hidden by the axial portion 30 and the second valve mounting portion 18 of the valve shaft 5, Mari throttle valve 4 of the dead band zone the flow rate of fresh intake air does not change in the valve fully open position near (0deg~θ1~θ2: see FIGS. 6 and 7) is formed.

  Thus, in the range from the fully open position of the throttle valve 4 to a predetermined rotation angle (about 0 to 30 deg), the intake passage on the upstream side of the throttle valve 4 passes through the air introduction passage 12 around the throttle valve 4, The new intake air flow toward the intake passage (including the merge chamber 13 and the air outlet passage 14) on the downstream side of the throttle valve 4 is not disturbed, and the axial portion 30 of the throttle valve 4 and the second valve mounting of the valve shaft 5 are installed. It flows smoothly along the outer shape of the portion 18. Therefore, since the intake resistance in the intake passage during the valve angle range (for example, 0 deg to θ1 to θ2 (about 30 deg)) used during regular running of a vehicle such as an automobile can be reduced, deterioration of fuel consumption can be prevented. .

In this embodiment, the first and second side cut portions 38 and 39 are provided on both sides of the throttle valve 4 in the vertical direction orthogonal to the rotation axis direction of the first and second valve bodies 31 and 32. However, the side cut portion may be provided only on one side in the vertical direction perpendicular to the rotation axis direction of the first and second valve bodies 31 and 32 of the throttle valve 4.
Further, if the side cut portion is provided, the outer diameters of the axial direction portion 30 of the throttle valve 4 and the second valve mounting portion 18 of the valve shaft 5 are set to be at least two of the first and second valve bodies 31 and 32. It is not necessary to make it larger than the thickness in the plate thickness direction. Further, without providing the side cut portion, the outer diameters of the axial direction portion 30 of the throttle valve 4 and the second valve mounting portion 18 of the valve shaft 5 are set to the plate thicknesses of at least two first and second valve bodies 31 and 32. It may be larger than the thickness in the direction.

[Effect of Example 1]
As described above, in the EGR valve module incorporated in the EGR system of this embodiment, as shown in FIG. 1, the first inlet pipe 21 of the housing 1 connected to the downstream end of the EGR pipe is connected to the intake air of the engine. A part of the duct (second inlet pipe 22, base 23 and outlet pipe 24) is connected at an acute angle (V-shaped connection). That is, in the EGR valve module of the present embodiment, the merging angle between the EGR gas passage 11 formed in the first inlet pipe 21 and the air introduction passage 12 formed in the second inlet pipe 22 is more than 90 degrees. A small angle (acute angle) is set.
Thereby, the flow path resistance resulting from the bending of the EGR gas passage 11 in the downstream portion of the EGR gas passage 11 can be reduced. For this reason, an increase in flow resistance due to bending of the EGR gas passage 11 can be suppressed, so that the flow rate of EGR gas (EGR amount: new intake) from the EGR gas passage 11 to the intake port for each cylinder of the engine A decrease in the EGR rate relative to the air amount and a decrease in engine output can be prevented.

Further, in the EGR valve module of the present embodiment, as shown in FIG. 1, the throttle valve 4 is disposed on the tip end side in the rotation axis direction (shaft axis direction) of the valve shaft 5 inside the air introduction passage 12 of the housing 1. The throttle valve 4 is attached to the second valve of the valve shaft 5 by caulking a pair of first and second locking claws 36, 37 formed at the lower end portions of the curved portions 34, 35 of the axial portion 30 in the figure. It is held and fixed to the portion 18. For this reason, the throttle valve 4 is in a cantilevered state at the tip end side in the rotation axis direction of the valve shaft 5 and is in a state of being easily vibrated.
Therefore, it is required that one of the two first and second bearings 6 and 7 that support the valve shaft 5 within the housing 1 (or the actuator body 9) be close to the throttle valve 4.

In the present embodiment, the first bearing 6 is installed on the distal end side of the valve shaft 5 in the rotation axis direction, and the second bearing 7 is installed on the actuator side. An elastic member 8 such as an O-ring is mounted between the inner circumference of the inner ring of the first bearing 6 on the side close to the distal end side in the rotation axis direction of the valve shaft 5 and the outer circumference groove of the valve shaft 5. . Thus, by installing the elastic member 8 that can be elastically deformed between the valve shaft 5 and the first bearing 6, the vibration of the throttle valve 4 and the valve that can easily vibrate in a cantilever state are provided. The backlash of the shaft 5 can be absorbed by the elastic member 8.
Further, since the EGR valve 3 and the throttle valve 4 are arranged on the same axis line in the rotation axis direction (shaft axis direction) of the common valve shaft 5, the overall size of the EGR valve module can be reduced in size. This makes it easy to secure a mounting space. Further, since the actuator main body 9 for driving the EGR valve 3 and the throttle valve 4 can be made common and the valve shaft 5 can be shared, the number of parts can be reduced and the cost can be reduced.

  The merging angle between the EGR gas passage 11 formed in the first inlet pipe 21 and the air introduction passage 12 formed in the second inlet pipe 22 is set to an angle (acute angle) smaller than 90 degrees. Thus, the valve shaft 5 is inserted (assembled) into the air introduction passage 12 of the housing 1 so as to be inclined with respect to an axial direction (center axis direction) passing through the center of the air introduction passage 12 of the housing 1. Further, in the EGR valve module of the present embodiment, after the valve shaft 5 is assembled in the air introduction passage 12 of the housing 1, the throttle valve 4 is disposed in the air introduction passage 12 at the front end side in the rotation axis direction of the valve shaft 5. Is configured to be assembled.

  Therefore, a pair of first and second locking claws 36 and 37 that are cut and raised in accordance with the width of the valve shaft 5 are formed at the lower end portions of the curved portions 34 and 35 of the axial direction portion 30 of the throttle valve 4. Yes. Thus, after the valve shaft 5 is assembled in the air introduction passage 12 of the housing 1, the pair of first and second locking claws 36 and 37 provided in the axial direction portion 30 of the throttle valve 4 are caulked. Thus, the throttle valve 4 can be fixed to the second valve mounting portion 18 of the valve shaft 5 inserted so as to be inclined with respect to the central axis direction of the air introduction passage 12 of the housing 1. Therefore, even when the rotational axis direction of the valve shaft 5 is installed obliquely with respect to the central axis direction (flow path direction) of the air introduction passage 12 of the housing 1, the air introduction passage 12 of the housing 1 is disposed inside the housing 1. The assembly of the throttle valve 4 to the second valve mounting portion 18 of the assembled (inserted) valve shaft 5 is facilitated.

  FIG. 8 shows a second embodiment of the present invention, and FIGS. 8A and 8B show a structure for assembling the throttle valve to the valve shaft.

  The throttle valve 4 of the present embodiment has an axial portion 30 extending in the rotational axis direction of the valve shaft 5 and both sides in the vertical direction perpendicular to the axial direction of the axial portion 30 with the axial portion 30 as a boundary. It has the 1st, 2nd valve main bodies 31 and 32 of the flat form (plate shape) extended. Similar to the first embodiment, the axial portion 30 and the two first and second valve bodies 31 and 32 are manufactured by press-molding a metal plate having a predetermined plate thickness. Further, the two first and second valve bodies 31 and 32 have first and second side cut portions 38 and 39 on both sides in the vertical direction orthogonal to the rotation axis direction.

Here, as for the 2nd valve mounting part 18 installed in the front-end | tip side of the rotation axis direction of the valve shaft 5 of a present Example, the cross section perpendicular | vertical to the rotation axis direction is formed circularly. That is, the second valve mounting portion 18 is formed in a cylindrical shape from a metal material. The outer diameters of the axial portion 30 of the throttle valve 4 and the second valve mounting portion 18 of the valve shaft 5 are larger than the thickness of at least two first and second valve bodies 31 and 32 in the plate thickness direction. Yes.
The axial direction portion 30 of the throttle valve 4 is formed in a cross-sectional arc shape (convex curved surface shape) along the outer shape (convex curved surface shape) of the second valve mounting portion 18.
Then, after the valve shaft 5 is assembled in the air introduction passage 12 of the housing 1, the shaft axial position of the axial portion 30 of the throttle valve 4 is positioned on the second valve mounting portion 18 of the valve shaft 5, and then the laser The throttle valve 4 is fixed to the second valve mounting portion 18 of the valve shaft 5 by welding both ends in the rotational axis direction of the axial direction portion 30 of the throttle valve 4 with a welding device or the like.

  FIG. 9 shows a third embodiment of the present invention, and FIGS. 9A and 9B show a structure for assembling the throttle valve to the valve shaft.

  The throttle valve 4 of the present embodiment is formed between two first and second valve bodies 31 and 32 that open and close the air introduction passage 12 of the housing 1, and these first and second valve bodies 31 and 32. It has a flat fitting part. The throttle valve 4 is formed by press-molding a metal plate having a predetermined thickness, so that the first and second sides of the first and second valve bodies 31 and 32 are arranged on both sides in the vertical direction perpendicular to the rotation axis direction. The second side cut portions 38 and 39 are obtained.

Here, as for the 2nd valve mounting part 18 installed in the front-end | tip side of the rotation axis direction of the valve shaft 5 of a present Example, the cross section perpendicular | vertical to the rotation axis direction is formed circularly. That is, the second valve mounting portion 18 is formed in a cylindrical shape from a metal material. Further, the second valve mounting portion 18 is formed with a valve insertion hole 40 into which the throttle valve 4 is inserted. The outer diameter of the second valve mounting portion 18 of the valve shaft 5 is larger than the thickness of at least two first and second valve bodies 31 and 32 in the plate thickness direction.
After the valve shaft 5 is assembled into the air introduction passage 12 of the housing 1, the throttle valve 4 is inserted into the valve insertion hole 40 formed in the second valve mounting portion 18 of the valve shaft 5, and the second valve mounting portion A fitting portion of the throttle valve 4 is fitted into the interior of 18. After positioning the throttle valve 4 in this way, the second valve mounting portion of the valve shaft 5 is welded by welding the base portions of the first and second valve bodies 31 and 32 of the throttle valve 4 with a laser welding device or the like. The throttle valve 4 is fixed to 18.

  FIG. 10 shows a fourth embodiment of the present invention and is a view showing a method for injection molding a throttle valve.

The throttle valve 4 of the present embodiment has a cylindrical axial portion 30 extending in the rotation axis direction of the second valve mounting portion (columnar outer diameter portion) 18 of the valve shaft 5 and the axial portion 30 as a boundary. The first and second valve bodies 31 and 32 are flat plate-like (plate-like) extending on both sides in the vertical direction orthogonal to the axial direction of the axial direction portion 30.
The axial portion 30 and the two first and second valve bodies 31 and 32 are mounted on the second valve mounting portion 18 of the valve shaft 5 after the valve shaft 5 is assembled in the air introduction passage 12 of the housing 1. Resin molding (injection molding).

Here, the injection molding apparatus according to the present embodiment includes an injection apparatus (not shown) having an injection cylinder and an injection nozzle, and a molten resin (heated and melted) from the injection nozzle of the injection apparatus via a resin supply channel. And an injection molding die from which a synthetic resin material (thermoplastic resin or the like) is injected.
The injection mold is used for injection molding the throttle valve 4 inside the air introduction passage 12 of the housing 1. The injection mold is a fixed mold composed of at least one mold (block) and at least one mold (slide). Block and slide core).
The injection mold (fixed mold and movable mold) is a product of the throttle valve 4 in which the axial direction portion 30 of the throttle valve 4 is insert-molded with the tip end side (second valve mounting portion 18) in the rotational axis direction of the valve shaft 5. A plurality of first and second molds 41 and 42 for forming a cavity (valve cavity) having a shape corresponding to the shape is provided. Note that at least one of the plurality of first and second molds 41 and 42 is provided with a resin supply channel and a gate that communicate the outside of the injection mold with the cavity. Further, it is desirable to use polyphenylene sulfide (PPS), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyphthalamide (PPA) or the like as a synthetic resin material for molding the throttle valve 4.

When resin molding (injection molding) of the throttle valve 4 is performed, first, a clamping force is applied to the first and second molds 41 and 42 of the injection mold to close the injection mold (mold closing step). At this time, a space surrounded by the passage wall surface of the air introduction passage 12 of the housing 1 and the plurality of first and second molds 41 and 42 becomes a valve cavity.
Next, when the filling process is started, the molten resin injected from the injection nozzle of the injection device passes through the gate and is filled into the valve cavity. That is, the molten resin is injected and injected from the injection nozzle into the injection mold (the plurality of first and second molds 41 and 42) via the resin supply flow path and filled into the valve cavity. At this time, the passage wall surface of the air introduction passage 12 of the housing 1 is used as a part of an injection mold for molding the outer peripheral end surface of the throttle valve 4.

Next, when the filling process is completed, a pressure holding process and a cooling process are started. In this pressure holding step, the pressure applied from the gate to the valve cavity is maintained substantially constant, and the contracted molten resin is replenished. That is, in the pressure-holding step for holding the molten resin in the valve cavity, the pressurized water is continuously applied to the molten resin in the valve cavity, and at the same time, cooling water is introduced into a cooling water passage (not shown) provided around the valve cavity. The molten resin that has contracted due to the cooling by the cooling water is replenished into the valve cavity from the injection nozzle.
Further, in the cooling process for cooling the molten resin in the valve cavity of the injection mold, the molten resin in the valve cavity is cooled and gradually cured (solidified) over time following the pressure holding process.
Next, after completion of the cooling process including the pressure holding process, the injection mold is opened (mold opening process).
As a result, the throttle valve 4 is mounted on the second valve mounting portion 18 of the valve shaft 5 inside the air introduction passage 12 of the housing 1 at an opening other than the fully closed opening of the throttle valve 4 (for example, a fully opened opening). Fixed. At this time, the second valve mounting portion 18 of the valve shaft 5 is insert-molded in the axial direction portion 30 of the throttle valve 4.

  FIG. 11 shows the fifth embodiment of the present invention, and FIGS. 11A and 11B show the dead zone of the throttle valve.

As shown in FIG. 11A, the electronic throttle device incorporated in the EGR valve module of the present embodiment inserts the tip end side (second valve mounting portion 18 having a circular cross section) of the valve shaft 5 in the rotation axis direction. A molded synthetic resin throttle valve 4 is provided.
In the throttle valve 4, the second valve mounting portion 18 is insert-molded so that the valve shaft 5 penetrates the cylindrical axial portion 30.

Here, the throttle valve 4 is a flat plate-shaped (plate-shaped) first and second valve body 31 extending on both sides in the vertical direction orthogonal to the axial direction of the axial direction portion 30 with the axial direction portion 30 as a boundary. 32. In addition, on both sides in the vertical direction orthogonal to the rotation axis direction of the two first and second valve bodies 31 and 32, predetermined end portions on the outer diameter side of the two first and second valve bodies 31 and 32 are provided. First and second side cut portions 38 and 39 are formed by removing the above range.
Further, by making the outer diameter of the axial portion 30 of the throttle valve 4 larger than the thickness of at least two first and second valve bodies 31 and 32 in the plate thickness direction, the throttle valve as in the first embodiment. A dead zone zone (about 0 to 30 deg) in which the flow rate of the new intake air does not change in the vicinity of the valve fully open position 4 is formed.
Therefore, in the electronic throttle device incorporated in the EGR valve module of the present embodiment, the valve angle range (for example, 0 deg to θ1 to θ2 (about 30 deg) used during normal running of a vehicle such as an automobile as in the first embodiment. ), The intake resistance in the intake passage can be reduced, so that deterioration of fuel consumption can be prevented.

Further, as shown in FIG. 11B, the electronic throttle device incorporated in the EGR valve module has a parallelogram shape on the tip end side (second valve mounting portion 18 having a circular cross section) of the valve shaft 5 in the rotation axis direction. The throttle valve 4 is held and fixed. The throttle valve 4 is formed with first and second side cut portions 38 and 39 from which triangular edge portions on both sides in the vertical direction perpendicular to the rotational axis direction are removed. As a result, as in the first embodiment, a dead zone (about 0 to 30 degrees) in which the flow rate of the new intake air does not change in the vicinity of the fully open position of the throttle valve 4 is formed.
Therefore, in the electronic throttle device incorporated in the EGR valve module of the present embodiment, the valve angle range (for example, 0 deg to θ1 to θ2 (about 30 deg) used during normal running of a vehicle such as an automobile as in the first embodiment. ), The intake resistance in the intake passage can be reduced, so that deterioration of fuel consumption can be prevented.

[Modification]
In this embodiment, the nozzle 2 is fitted and held on the inner periphery of the nozzle fitting portion of the housing 1, and the EGR valve 3 is accommodated in the nozzle 2 so as to be opened and closed. The EGR valve 3 may be accommodated directly in the part so as to be freely opened and closed. In this case, the nozzle 2 becomes unnecessary, and the number of parts and the number of assembling steps can be reduced. Further, it is not necessary to install a coil spring (valve urging means) for urging the EGR valve 3 in the valve closing direction or the valve opening direction. In this case, the number of parts and assembly man-hours can be reduced.

In this embodiment, an actuator body 9 that drives two first and second valves (EGR valve 3 and throttle valve 4) via a valve shaft 5 is replaced with an electric motor and a power transmission mechanism (for example, a gear reduction mechanism). However, the actuator that drives the valve via the shaft is a negative pressure actuated actuator that includes an electromagnetic or electric negative pressure control valve, and an electromagnetic that includes an electromagnet including a coil. You may comprise by a type actuator.
Further, as an internal combustion engine (for example, a traveling engine) mounted on a vehicle such as an automobile, not only a diesel engine but also a gasoline engine may be used.

In this embodiment, two first and second bearings (ball bearings) 6 and 7 are used as bearing members. However, sintered bearings, resin bearings, sliding bearings, rolling bearings, and needle bearings are used as bearing members. Alternatively, a metal bearing or the like may be used.
In this embodiment, a thermoplastic resin is used as the synthetic resin material for molding the throttle valve 4, but a thermosetting resin such as unsaturated polyester (UP) is used as the synthetic resin material for molding the throttle valve 4. It may be adopted.
Further, an aluminum alloy or a magnesium alloy may be used as a metal material for forming the housing 1 and the throttle valve 4.

It is the block diagram which showed the EGR valve module (Example 1). It is sectional drawing which showed the 1st bearing and the elastic member (Example 1). (A) is explanatory drawing which showed the fully closed state of the throttle valve, (b) is explanatory drawing which showed the fully open state of the throttle valve (Example 1). (A) is AA sectional drawing of (b), (b) is sectional drawing which showed the assembly | attachment structure of the throttle valve to a valve shaft (Example 1). (A) is explanatory drawing which showed the assembly method of the throttle valve to a valve shaft, (b) is a top view which showed the throttle valve, (c) is the side surface which showed the 2nd valve mounting part periphery of the valve shaft. (Example 1) which is a figure. (A)-(c) is explanatory drawing which showed the dead zone of the throttle valve (Example 1). 6 is a graph showing an intake air side flow rate characteristic and an EGR gas side flow rate characteristic with respect to a rotation angle (valve opening degree) of the valve shaft (Example 1). (A), (b) is the side view and the top view which showed the assembly | attachment structure of the throttle valve to a valve shaft (Example 2). (A), (b) is the side view and the top view which showed the assembly | attachment structure of the throttle valve to a valve shaft (Example 3). (Example 4) which is the explanatory view which showed the injection molding method of the throttle valve. (A), (b) is explanatory drawing which showed the dead zone of the throttle valve (Example 5). It is the block diagram which showed the confluence | merging part of an intake passage and a PCV passage (conventional technique).

Explanation of symbols

1 Housing 3 EGR valve (first valve)
4 Throttle valve (second valve)
5 Valve shaft 6 First bearing (first bearing member, ball bearing)
7 Second bearing (second bearing member, ball bearing)
8 Elastic member 9 Actuator body 11 EGR gas passage (exhaust gas passage)
12 Air introduction passage (intake air passage)
13 Junction chamber (merging section of exhaust gas passage and intake air passage)
14 Air outlet passage 18 Second valve mounting part of valve shaft (second valve holding part)
30 Axial portion of throttle valve 31 First valve body of throttle valve 32 Second valve body of throttle valve 36 First locking claw of throttle valve 37 Second locking claw of throttle valve 38 First side cut portion of throttle valve 39 Second side cut of throttle valve

Claims (8)

In an exhaust gas recirculation device that recirculates exhaust gas to an intake port of an internal combustion engine,
(A) a housing having an exhaust gas passage communicating with the intake port and an intake air passage communicating with the intake port;
(B) a first valve that is rotatably accommodated in the housing and opens and closes an exhaust gas passage upstream of a junction of the exhaust gas passage and the intake air passage;
(C) a second valve that is rotatably accommodated in the housing and opens and closes an intake air passage upstream of a junction of the exhaust gas passage and the intake air passage;
(D) a shaft that coaxially arranges these two first and second valves;
(E) including one actuator that drives the two first and second valves via the shaft;
The exhaust gas recirculation apparatus according to claim 1, wherein a confluence angle between the exhaust gas passage and the intake air passage is set to an angle smaller than 90 degrees. The exhaust gas recirculation device according to claim 1,
The first valve is fixed to a central portion of the shaft in the axial direction;
The exhaust gas recirculation device, wherein the second valve is fixed to an end portion on the opposite side to the actuator side in the axial direction of the shaft. The exhaust gas recirculation device according to claim 1 or 2,
The second valve includes an axial portion extending in the axial direction of the shaft, and a plate-like valve body extending on both sides in the vertical direction perpendicular to the axial direction of the axial portion with the axial portion as a boundary. An exhaust gas recirculation device comprising the exhaust gas recirculation device. The exhaust gas recirculation device according to claim 3,
The exhaust gas recirculation device, wherein the valve body has a side cut portion on one side in a vertical direction orthogonal to the axial direction of the axial portion. The exhaust gas recirculation device according to claim 3 or 4,
The shaft has a valve holding portion for fixing the axial direction portion,
The exhaust gas recirculation device according to claim 1, wherein an outer diameter of the valve holding portion is at least larger than a thickness of the valve body in a plate thickness direction. The exhaust gas recirculation device according to any one of claims 1 to 5,
The exhaust gas recirculation device, wherein the second valve has a pair of locking claws cut and raised in accordance with the width of the shaft. The exhaust gas recirculation device according to any one of claims 1 to 6,
The exhaust gas recirculation device, wherein the shaft is rotatably supported by the housing via a bearing member fixed to the housing. The exhaust gas recirculation device according to claim 7,
An exhaust gas recirculation device, wherein an elastic member capable of elastic deformation is mounted between an outer periphery of the shaft and an inner periphery of the bearing member.

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