JP2010121569A - Exhaust gas recirculation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deterioration of fuel economy by reducing intake resistance in an intake air passage (an intake passage of an internal combustion engine) during ordinary traveling of a vehicle such as an automobile. <P>SOLUTION: In the exhaust gas recirculation device, during a first period (during ordinary traveling of the vehicle) until a rotation angle of a valve shaft 4 reaches a prescribed rotation angle (θ=45 degrees) from a minimum rotation angle (θ=0 degree), a link lever 6 fixed by the valve shaft 4 is separated from a throttle valve 2, and the throttle valve 2 and the valve shaft 4 are not connected with each other. During a second period until the rotation angle of the valve shaft 4 reaches a maximum rotation angle (θ=100 degrees) from the prescribed rotation angle, the link lever 6 is abutted and fitted to the throttle valve 2, and the throttle valve 2 and the valve shaft 4 are connected with each other. Accordingly, the intake resistance in the intake air passage during ordinary traveling of the vehicle can be reduced, and deterioration of the fuel economy can be prevented. <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 system 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.

The throttle valve 104 shown in FIG. 12 performs a valve closing operation (a valve closing operation of the throttle valve 104) that rotates from the fully open state (initial state) where the intake passage 101 is fully opened to the side where the intake passage 101 is closed. It is configured. 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 arises a problem that the fuel consumption is deteriorated by the amount of the increase in the intake resistance in the intake passage 101 during normal running of a vehicle such as an automobile.
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 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, the two first and second valves are arranged on the same axis, and the actuator for rotating the shafts for driving the two first and second valves is shared, and the shaft is connected between the two first and second valves. Since they are shared, the number of parts and the cost can be reduced.
An electric actuator having a motor that generates a driving force for driving the two first and second valves when supplied with electric power may be employed as the actuator.

The link installed on the shaft is connected to the shaft only during a period (second period) until the rotation angle of the shaft reaches the maximum rotation angle from the specified rotation angle that is larger than the minimum rotation angle and smaller than the maximum rotation angle. The second valve is configured to be connected.
As a result, during the period from the minimum rotation angle to the specified rotation angle (the first period), the shaft and the second valve are disconnected from each other, and the shaft rotation angle changes. However, the opening / closing operation (for example, valve closing operation) of the second valve is not started.
This makes it difficult for the intake air flow from the intake air passage upstream of the second valve to pass through the periphery of the second valve and toward the intake air passage (including the merging portion) downstream of the second valve, It becomes easy to flow smoothly along the shape of the second valve. Therefore, since the intake resistance in the intake air passage during normal running of the vehicle (corresponding to the period until the shaft rotation angle reaches the specified rotation angle from the minimum rotation angle) can be reduced, deterioration of fuel consumption can be prevented. it can.

According to the second aspect of the present invention, the link causes the shaft and the second valve to be disconnected from each other during the first period until the rotation angle of the shaft reaches the specified rotation angle from the minimum rotation angle. It is configured. The link is configured to connect the shaft and the second valve during the second period until the rotation angle of the shaft reaches the maximum rotation angle from the specified rotation angle. That is, the link opens and closes the second valve (for example, the valve closing operation) for the first valve opening and closing operation (for example, the valve opening operation) only in the second period until the shaft rotation angle reaches the maximum rotation angle from the specified rotation angle. Operation).
Accordingly, during the first period, the opening / closing operation (for example, the valve closing operation) of the second valve is not started, so that the second valve passes from the intake air passage on the upstream side of the second valve through the periphery of the second valve. However, the intake air flow toward the intake air passage on the downstream side (including the merging portion) is less likely to be turbulent, and can easily flow smoothly along the shape of the second valve. Therefore, since the intake resistance in the intake air passage during normal running of the vehicle can be reduced, fuel consumption can be prevented from deteriorating.

The first valve may be always connected to the shaft that drives the two first and second valves, and the second valve may be temporarily connected. In this case, the first valve is connected to the shaft and driven by the driving force of the actuator over both the first period and the second period, that is, over the entire rotation angle range of the shaft.
The second valve is not connected to the shaft during the first period and is connected to the shaft only during the second period. That is, it is connected to the shaft only during the second period and is driven by the driving force of the actuator. Thereby, the opening / closing operation (for example, valve opening operation) of the first valve and the opening / closing operation (for example, valve closing operation) of the second valve are interlocked only during the second period.

According to the third aspect of the present invention, the link delays the timing for starting the fully closing operation of the second valve by the specified rotational angle with respect to the timing for starting the fully opening operation of the first valve. It is configured.
Note that the first valve may be set in an initial state in which the exhaust gas passage upstream of the merging portion is fully closed when the rotation angle of the shaft is the minimum rotation angle. Further, the second valve is set to an initial state in which the intake air passage upstream of the merging portion is fully opened during the period (first period) until the rotation angle of the shaft reaches the specified rotation angle from the minimum rotation angle. You may do it. Further, during the opening operation of the first valve, the first valve is rotationally driven from the fully closed state (initial state) where the exhaust gas passage on the upstream side of the merging portion is fully closed to the opening side (the valve opening operation direction). . Further, during the valve closing operation of the second valve, the second valve is rotationally driven from the fully open state (initial state) in which the intake air passage upstream of the merging portion is fully opened to the closed side (valve closing operation direction).

According to the fourth aspect of the present invention, the housing has the fully open stopper that restricts the fully open state of the second valve.
According to the fifth aspect of the present invention, the biasing torque is applied to the second valve so as to bias the second valve in the fully opening direction (for example, the side pressing the second valve against the fully opening stopper). Means. Thereby, since the connection strength (engagement strength) of the connection state between the shaft and the second valve during the second period can be improved, the connection state between the shaft and the second valve and the connection between the shaft and the second valve are not connected. The reliability of the valve drive mechanism having the state can be ensured.
When the biasing torque applying means is constituted by a coil spring that is sandwiched between the second valve and the shaft in a state of being compressed and deformed, the coil spring receives a load from the second valve and the shaft, and the biasing torque is applied. Generate torque.

According to invention of Claim 6, the link is being fixed to the edge part on the opposite side with respect to the actuator side of the axial direction of a shaft.
According to the seventh aspect of the present invention, the link has an engaging portion that is detachably engaged with the second valve.
According to the invention described in claim 8, the shaft supports the second valve slidably (in the axial direction and the rotational direction). That is, a predetermined sliding clearance is formed between the shaft and the second valve.
According to the ninth aspect of the present invention, the shaft has a guide that slidably supports the second valve. The second valve has a through hole extending in the axial direction of the shaft. For example, the through hole penetrates the second valve in the axial direction of the shaft.
Further, the shaft guide is provided, for example, at an end portion on the opposite side to the actuator side in the axial direction of the shaft. The guide is inserted so as to penetrate the through hole formed in the second valve in the axial direction.

  According to the invention described in claim 10, the outer diameter of the guide gradually decreases from the end on the actuator side in the axial direction of the shaft toward the end opposite to the actuator side in the axial direction of the shaft. It is formed in a truncated cone shape. The through hole of the second valve is formed in a tapered hole shape corresponding to the truncated cone shape of the guide. As a result, when the shaft guide is inserted into the through hole of the second valve, the guide can be smoothly inserted into the through hole of the second valve without being caught by the wall surface of the tapered hole of the second valve. . Therefore, for example, even when the shaft is installed obliquely with respect to the axial direction (flow path direction) of the intake air passage of the housing, the through hole of the second valve incorporated in the intake air passage of the housing The shaft can be easily assembled to the shaft.

According to the eleventh aspect, a predetermined sliding clearance is formed between the tapered guide surface of the shaft and the tapered hole wall surface of the second valve. That is, between the taper guide surface of the shaft and the taper hole wall surface of the second valve, the shaft guide can be smoothly rotated in the rotation direction within the through hole of the second valve (and smoothly in the axial direction). In order to be movable in the thrust direction), a predetermined sliding clearance is formed.
According to the twelfth aspect of the invention, the second valve is provided with load applying means for applying a load for urging the second valve to the opposite side with respect to the actuator side in the axial direction of the shaft. Thereby, said sliding clearance can be ensured stably.
In addition, you may give the function as an urging | biasing torque provision means of Claim 5 to a load provision means. In this case, the number of parts and the cost can be reduced.

According to the thirteenth aspect of the present invention, the housing has a duct in which a throttle bore corresponding to the intake air passage on the upstream side of the junction is formed. The second valve has a valve plate having a shape different from the cross-sectional shape of the throttle bore. Then, the profile (contour) of the valve plate is changed based on the intake air flow characteristics set in accordance with the specifications of the internal combustion engine or the vehicle type.
Here, the first valve is a butterfly-type EGR valve (exhaust gas recirculation amount) that controls exhaust gas recirculation characteristics (exhaust gas discharged from the internal combustion engine, particularly the flow characteristics of EGR gas) in accordance with the rotation angle of the shaft. The valve body of the control valve). The second valve is a butterfly type throttle valve (a valve body of an intake air flow rate control valve) that controls the intake air flow rate characteristic (particularly the flow rate characteristic of clean air filtered by an air cleaner) according to the rotation angle of the shaft. It is.

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 duct) of the internal combustion engine and the intake pipe (intake introduction duct) of the internal combustion engine are set to V Realized by connecting in a letter shape.
And, for the purpose of reducing the intake resistance in the intake air passage during normal running of the vehicle and preventing the deterioration of fuel consumption, only in the second period until the rotation angle of the shaft reaches the maximum rotation angle from the specified rotation angle, This was realized by linking the opening / closing operation (for example, valve closing operation) of the second valve with the opening / closing operation (for example, valve opening operation) of the first valve.

[Configuration of Example 1]
FIGS. 1 to 7 show a first embodiment 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. FIG. 3 and FIG. 4 are views showing a structure for assembling a coil spring to a throttle valve.

An exhaust gas recirculation device (EGR system) for an internal combustion engine according to the present embodiment uses EGR gas (exhaust recirculation gas), which is a part of exhaust gas from an internal combustion engine (hereinafter referred to as an engine) such as a diesel engine, for example. An exhaust gas recirculation pipe (EGR duct) that recirculates to the intake port for each cylinder and an EGR valve module installed at a connection portion between the EGR duct 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 that recirculates to the intake port of the engine, and new intake air that is introduced into the intake port of the engine. An electronic throttle device (throttle device for an internal combustion engine) that controls the flow rate is combined and integrated.
The EGR valve module includes a valve housing (hereinafter abbreviated as a housing) 3 in which an EGR valve 1 which is an EGRV valve body and a throttle valve 2 of an electronic throttle device are built in a freely openable and closable (rotatable) manner. That is, the housing 3 is a common valve body for the EGRV and the electronic throttle device.

  The housing 3 is formed in a predetermined shape by, for example, a heat-resistant material having excellent high-temperature heat resistance (for example, iron-based casting or cast iron), a heat-resistant aluminum alloy die-casting, or an aluminum alloy-based casting. This housing 3 connects an outlet (EGR port) of a first duct (EGR duct) 11 through which EGR gas flows to a second duct (intake air introduction duct) 12 through which new intake air (clean air) filtered by an air cleaner flows. This is a three-way junction pipe. Further, the EGR duct 11 is provided with a cylindrical nozzle fitting portion that fits and holds a cylindrical nozzle (cylindrical portion) 13.

An EGR passage (exhaust gas passage) 14 into which EGR gas is introduced via the EGR gas passage in the EGR duct is formed inside the EGR duct 11. In addition, an air introduction passage (intake air passage: an intake passage of an internal combustion engine) 15 through which clean air is introduced via an intake passage in an upstream intake duct, an EGR passage, and the intake introduction duct 12 are provided. 14 and an air introduction flow path 15 (intake passage of internal combustion engine, mixing chamber: hereinafter referred to as a merging chamber) 16, and for evacuating intake air from the merging chamber 16 toward the intake port side of the engine An air outlet passage (intake passage of the internal combustion engine) 17 is formed.
Details of the housing 3 will be described later.

The EGRV is installed (mounted) in the EGR duct 11 of the housing 3, and a butterfly-type EGR valve (exhaust gas flow rate control valve, first valve) 1 that opens and closes the EGR flow path 14 and the EGR valve 1 are always connected. A valve shaft 4 to be connected and an electric actuator for driving the EGR valve 1 through the valve shaft 4 are provided.
The electronic throttle device is installed (mounted) in the intake air introduction duct 12 of the housing 3, and a butterfly throttle valve (second valve) 2 that opens and closes the air introduction flow path 15, and the throttle valve 2 temporarily. A valve shaft 4 to be connected and an electric actuator for driving the throttle valve 2 through the valve shaft 4 are provided.

Here, a coil spring 5 is installed between the throttle valve 2 and the valve shaft 4 so as to surround the periphery of the valve shaft 4 in the circumferential direction of the shaft. Further, a link lever 6 is joined and fixed to the end portion (tip portion) opposite to the actuator side in the rotation axis direction of the valve shaft 4 by using joining means such as laser welding.
The valve shaft 4 of this embodiment 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 bearings (first and second bearing members). 7 and 8 are rotatably supported with respect to the housing 3.

  The valve shaft 4 is a valve drive shaft that arranges the EGR valve 1 and the throttle valve 2 on the same axis and drives the EGR valve 1 and the throttle valve 2. Further, the valve shaft 4 is formed straight in the rotation axis direction from one end side to the other end side. The valve shaft 4 passes through the EGR flow path 14 and the axial hole 18 of the housing 3 and is inserted into the air introduction flow path 15 of the housing 3 from the inside of the electric actuator.

The valve shaft 4 has one end portion in the rotation axis direction coupled to a final reduction gear, which will be described later, and the EGR valve 1 is fastened and fixed to the center portion (actuator side) in the rotation axis direction by using a screw 21 (fastening fixation). A second valve mounting portion (second valve holding portion: hereinafter referred to as a valve guide) that has a first valve mounting portion (first valve holding portion) that slidably supports the throttle valve 2 at the other end in the rotational axis direction. 22). A fastening hole into which the screw 21 is screwed is formed in the first valve mounting portion of the valve shaft 4.
Details of the valve shaft 4 will be described later.

  The two bearings 7 and 8 slide between the inner ring fixed to the outer peripheral side of the valve shaft 4, the outer ring press-fitted to the housing side of the housing 3 and the electric actuator, and the two race rings of the inner ring and the outer ring. A plurality of steel balls (rolling elements, steel balls) that are freely accommodated and roll between the raceway surface of the inner ring and the raceway surface of the outer ring, and are provided outside the valve shaft 4 by rolling friction of the plurality of steel balls. A ball bearing that supports the diameter portion so as to be slidable in the rotational direction is employed. Of the two bearings 7 and 8, the outer ring of the bearing 7 installed on the actuator side is press-fitted and fixed to the hole wall surface of the axial hole (shaft insertion hole) of the housing (described later) of the electric actuator. Further, the outer ring of the bearing 8 installed on the side close to the tip of the valve shaft 4 in the rotational axis direction is press-fitted and fixed to the hole wall surface of the axial hole (shaft insertion hole) 18 of the housing 3.

The EGR valve 1 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 1 is accommodated in a nozzle 13 fitted in a nozzle fitting portion of a housing 3 so as to be freely opened and closed. The EGR valve 1 continuously variably adjusts the opening degree of the EGR flow path 14 of the housing 3 by changing the rotation angle about the rotation axis of the valve shaft 4. Thereby, the flow rate of EGR gas recirculated from the exhaust passage to the intake passage (EGR amount: EGR rate with respect to the new intake air amount) is arbitrarily variably controlled.
The EGR valve 1 is opened / closed within the operable range from the fully closed position to the fully open position based on a control signal from an engine control unit (hereinafter referred to as ECU) during engine operation (valve open operation, valve close operation, By changing the rotation angle), the opening area (EGR gas flow area) of the EGR flow path 14 is changed to variably control the EGR amount.
The EGR valve 1 is held and fixed at an intermediate position in the rotation axis direction of the valve shaft 4 in a state inclined by a predetermined inclination angle with respect to the rotation axis direction (shaft axis direction, rotation axis direction) of the valve shaft 4. .

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 1. A C-shaped seal ring that can be brought into close contact with the inner diameter surface of the nozzle 13 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 the state where the outer diameter side end protrudes from the outer peripheral end surface of the EGR valve 1. It is fitted inside. Therefore, in the EGR valve module of the present embodiment, when the EGR valve 1 is stopped at the fully closed position, that is, the EGR valve 1 is set in the vertical direction perpendicular to the flow direction of the EGR flow path 14. (When the EGR valve 1 is fully closed), the tension between the inner diameter surface of the nozzle 13 and the outer peripheral end surface of the EGR valve 1 is utilized by utilizing the radial (expansion direction) tension of the seal ring fitted in the seal ring groove. It is comprised so that the clearance gap between them may be sealed (sealed).
Details of the EGR valve 1 will be described later.

The throttle valve 2 of the present embodiment is formed in a predetermined shape from a synthetic resin material. The throttle valve 2 is housed inside the housing 3 so as to be freely opened and closed. The throttle valve 2 continuously variably adjusts the opening degree of the air introduction passage 15 of the housing 3 by changing the rotation angle about the rotation axis of the valve shaft 4. Thereby, the flow rate of the new intake air with respect to the EGR gas is arbitrarily variably controlled.
The throttle valve 2 opens and closes (changes the valve closing operation, the valve opening operation, and the rotation angle) within the operable range from the fully open position to the fully closed position based on a control signal from the ECU during engine operation. Thus, the opening area (new intake air flow area) of the air introduction flow path 15 is changed to variably control the flow rate of the new intake air.

The throttle valve 2 is disposed on a valve shaft 4 as a shaft member with a predetermined angle with respect to the EGR valve 1. That is, the EGR valve 1 and the throttle valve 2 are disposed coaxially with the valve shaft 4.
Here, the tip end side of the valve shaft 4 in the shaft axial direction (the portion where the throttle valve 2 is mounted) is placed inside the housing 3 so as to be inclined with respect to a vertical line perpendicular to the flow direction of the air introduction flow path 15. Has been inserted. For this reason, the rotational axis direction of the throttle valve 2 is also inclined with respect to a vertical line perpendicular to the flow direction of the air introduction flow path 15.
The details of the throttle valve 2 will be described later.

The electric actuator receives an electric power supply and generates an electric motor (for example, a DC motor) that generates a rotational driving force (driving torque) for driving the EGR valve 1 and the throttle valve 2, and the driving torque of the electric motor is expressed by the EGR valve 1. And a power transmission mechanism for transmitting to a common valve shaft 4 for the throttle valve 2. The power transmission mechanism includes a gear reduction mechanism that reduces the rotational speed of the electric motor by two stages so as to achieve a predetermined reduction ratio, and increases the drive torque of the electric motor.
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. The three gears constituting the gear reduction mechanism are rotatably accommodated in an internal space formed between the actuator mounting portion formed on the outer wall portion of the housing 3 and the housing 23 of the electric actuator.

In the electric actuator, the opening of the housing 23 is closed by the sensor cover 24. The housing 23 of this electric actuator is a die-cast product made of an aluminum alloy, and is coupled (fastened and fixed) to an actuator mounting portion formed on the outer wall portion of the housing 3 by using a plurality of fastening bolts.
A coil spring that urges the EGR valve 1 in the valve closing operation direction is provided in the housing 23 of the electric actuator. An oil seal and a bearing 7 are fitted and held between the valve shaft 4 and the bearing portion of the housing 23.
In addition, an EGR gas flow sensor that converts the rotation angle of the valve shaft 4 into an electrical signal and outputs how much the EGR valve 1 and the throttle valve 2 are open to the ECU is mounted in the housing 23 of the electric actuator. Yes.
An electric motor is held and fixed in a motor housing 25 formed integrally with the housing 23.

Then, the electric actuator changes the rotation angle of the valve shaft 4 between the minimum rotation angle (θ = 0 deg) and the maximum rotation angle (θ = 100 deg) as shown in the characteristic diagram of FIG. Thereby, the opening / closing operation of the EGR valve 1 and the opening / closing operation of the throttle valve 2 are performed.
The opening / closing operation of the EGR valve 1 is a valve opening operation in which the EGR flow path 14 on the upstream side of the merging chamber 16 is rotated from the fully closed state (initial state) to the opening side in the valve rotation direction (the valve opening operation direction). Operation (opening operation of the EGR valve 1), and valve closing operation (closing operation of the EGR valve 1) for rotating the valve from the opened state in which the EGR flow path 14 is opened to the closing side (valve closing operation direction) of the valve rotation direction ).

Further, the opening / closing operation of the throttle valve 2 is a closing operation in which the air introduction flow path 15 upstream from the merging chamber 16 is fully opened (initial state) to be rotated to the valve rotation direction closing side (valve closing operation direction). The valve operation (the valve closing operation of the throttle valve 2), and the valve opening operation (the opening of the throttle valve 2) that rotates from the closed state in which the air introduction passage 15 is closed to the opening side in the valve rotation direction (the valve opening operation direction). Valve operation).
Here, the electric motor which is a power source of the electric actuator 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.
Further, when the ignition switch (not shown) is turned on (IG / ON), the ECU sets the valve opening (valve opening) of the EGR valve 1 and the throttle valve 2 based on the 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 24.

Next, details of the housing 3 of the present embodiment will be described with reference to FIGS. 1 and 2.
The housing 3 is formed of a metal material such as stainless steel having excellent heat resistance and corrosion resistance only on the sliding portion near the fully closed position where the seal ring mounted on the outer peripheral end face of the EGR valve 1 is in sliding contact. The cylindrical nozzle 13 is press-fitted and fixed to the inner wall surface of the nozzle fitting portion of the EGR duct 11. The housing 3 is a three-way pipe that is connected to the downstream end of the EGR duct and in the middle of the intake duct, and in which the merge chamber 16 is formed.
The housing 3 includes a cylindrical intake introduction duct 12 having a throttle bore having a circular cross section corresponding to the air introduction flow path 15 upstream of the merge chamber 16, and the axial direction of the intake introduction duct 12 (intake flow). The cylindrical EGR duct 11 protrudes upstream (exhaust passage side) in the EGR gas flow direction.
Note that the intake air introduction duct 12 has a cylindrical inlet pipe projecting upstream of the new intake air flow direction (air cleaner side) from the merge chamber 16 and an EGR gas flow direction (new intake air flow direction) from the merge chamber 16. ), A cylindrical outlet pipe or the like protruding to the downstream side (surge tank side or intake manifold side).

Here, an EGR flow path 14 is formed inside the EGR duct 11. In addition, an air introduction channel 15, a merging chamber 16, and an air outlet channel 17 are formed inside the intake introduction duct 12. The EGR duct 11 and the intake air intake duct 12 are connected by a connecting block 26 in which an axial hole 18 is formed.
The EGR duct 11 has a smaller inner diameter than the intake air introduction duct 12 and is connected to the intake air introduction duct 12 at an acute angle (V-shaped connection). That is, in the EGR valve module of the present embodiment, the merging angle between the EGR flow path 14 formed in the EGR duct 11 and the air introduction flow path 15 formed in the intake air introduction duct 12 is an angle smaller than 90 degrees. (Acute angle) is set.
The EGR flow path 14 is inclined with respect to an axis (the central axis of the intake air path) passing through the center of the intake air passage (the air introduction flow path 15, the merging chamber 16, and the air outlet flow path 17) of the intake air introduction duct 12. An inclined passage (exhaust gas passage) that extends straight in a straight line is formed. Moreover, the air introduction flow path 15, the merging chamber 16, and the air outlet flow path 17 constitute a straight passage (intake air passage) that extends straight along the central axis of the intake passage.

The EGR duct 11 has a first flange attached to a coupling end surface provided at the downstream end of the EGR duct. An actuator mounting portion for mounting the electric actuator is provided on the outer peripheral surface of the EGR duct 11.
The intake air introduction duct 12 has a second flange attached to a coupling end surface provided at the downstream end of the intake duct on the air cleaner side, and a coupling end surface provided at the upstream end of the intake duct (surge tank or intake manifold) on the intake port side of the engine. And a third flange attached to the.
Further, the intake duct 12 of the housing 3 has a fully open stopper 19 that regulates the fully open state of the throttle valve 2. The fully open stopper 19 engages the throttle valve 2 when the throttle valve 2 is fully opened, so that the throttle valve 2 is stopped when the throttle valve 2 is fully opened (fully opened position). Is restricted (rotation to the opening side).

Next, details of the EGR valve 1 of this embodiment will be described with reference to FIG.
The EGR valve 1 includes a cylindrical axial part (shaft part, thick part) extending in the rotational axis direction of the first valve mounting part of the valve shaft 4 and the axial direction of the axial part with this axial part as a boundary. It has a disc-shaped (plate-shaped) valve body (valve plate) extending on both sides in a vertical direction perpendicular to the vertical direction. These axial portions and the valve plate are manufactured by press-molding a metal plate having a predetermined thickness. When the axial portion and the valve plate are manufactured separately, the axial portion and the valve plate are integrated by welding with a laser welding apparatus or the like.
The valve plate of the EGR valve 1 has a rotation angle range (the operable range of the EGR valve 1) until the rotation angle of the valve shaft 4 reaches the maximum rotation angle (θ = 100 deg) from the minimum rotation angle (θ = 0 deg). ), The valve opening (the rotation angle of the EGR valve 1) is changed from the fully closed state (that is, the fully closed position where sealing is possible) to the EGR channel 14 being fully closed to the fully opened state (fully opened position) where the EGR channel 14 is fully opened. Be changed.
Since the EGR valve 1 is supported and fixed (always connected) to the valve shaft 4, the rotation angle of the EGR valve 1 and the rotation angle of the valve shaft 4 have the same value.

  In the EGR valve 1, the valve shaft 4 is assembled in the EGR flow path 14 of the EGR duct 11, and then held and fixed in the EGR flow path 14 at an intermediate portion (central portion) in the rotation axis direction of the valve shaft 4. That is, a shaft through-hole through which the first valve mounting portion of the valve shaft 4 passes is formed in the axial direction portion of the EGR valve 1, and when assembling the valve shaft 4 inside the EGR duct 11, a jig or the like Thus, the valve shaft 4 is passed through the shaft through hole of the EGR valve 1 held in the EGR flow path 14. Then, after passing the valve shaft 4 through the shaft through hole of the EGR valve 1, the axial direction portion of the EGR valve 1 is fastened and fixed to the first valve mounting portion of the valve shaft 4 using the screw 21.

Next, details of the throttle valve 2 of this embodiment will be described with reference to FIGS.
The throttle valve 2 is integrally formed of a synthetic resin material. The throttle valve 2 includes a truncated cone-shaped axial portion (shaft portion, thick portion) 30 extending in the rotational axis direction of the valve guide 22 of the valve shaft 4, and an axial portion with the axial direction portion 30 as a boundary. The valve plate (valve body) has an elliptical plate shape (plate shape) extending on both sides in the vertical direction orthogonal to the 30 axial directions.

The valve plate of the throttle valve 2 is formed in an elliptical shape different from the cross-sectional shape of a throttle bore (air introduction flow path 15 having a circular cross section) formed in the intake air introduction duct 12. The valve plate of this embodiment is divided into two first and second valve plates (hereinafter abbreviated as valve plates) 31 and 32 with the axial portion 30 as a boundary. The valve plate 31 is disposed upstream of the axial direction portion 30 in the axial direction (intake air flow direction) of the air introduction flow path 15 when the throttle valve 2 is fully opened. Further, the valve plate 32 is disposed downstream of the axial direction portion 30 in the axial direction (intake flow direction) of the air introduction flow path 15 when the throttle valve 2 is fully opened.
In addition, the valve plates 31 and 32 of the throttle valve 2 have an air introduction flow during the rotation angle range until the rotation angle of the valve shaft 4 reaches the specified rotation angle (θ = 45 deg) from the minimum rotation angle (θ = 0 deg). The fully open state where the path 15 is fully opened is maintained. In addition, the valve plates 31 and 32 of the throttle valve 2 have a rotation angle range (a range in which the EGR valve 1 can be operated) until the rotation angle of the valve shaft 4 reaches the maximum rotation angle (θ = 100 deg) from the specified rotation angle. In a small rotation angle range), the valve opening (throttle valve) from the fully open state (fully open position) where the air introduction channel 15 is fully opened to the fully closed state (that is, fully sealable position) where the air introduction channel 15 is fully closed. 2) is changed.

The profile (contour) of the two valve plates 31 and 32, in particular the ellipticity (ratio of major axis to minor axis) of the valve plates 31 and 32, is a flow rate of new intake air set according to the engine specification or vehicle type. It is changed based on characteristics. The major axis is the dimension in the major axis direction of the two valve plates 31, 32, and the minor axis is the dimension in the minor axis direction of the two valve plates 31, 32. The major axis direction or minor axis direction of the two valve plates 31, 32 is slightly inclined with respect to the rotational axis direction of the valve shaft 4.
The axial direction portion 30 of the throttle valve 2 has a predetermined distance on the actuator side from the elliptical curved surfaces on the actuator side of the two valve plates 31 and 32 (outer peripheral end surfaces perpendicular to both the front and back sides of the two valve plates 31 and 32). It has a conical cylindrical protrusion (spring holding part) 33 protruding by a protrusion amount.

  Further, a shaft through hole (hollow portion) 34 extending in the rotation axis direction of the valve shaft 4 is formed inside the axial direction portion 30. A valve guide (tapered sliding shaft) 22, which is the distal end side of the valve shaft 4 in the rotational axis direction, is inserted into the shaft through hole 34. The shaft through hole 34 is formed in a tapered hole shape corresponding to the truncated cone shape (tapered shape) of the valve guide 22. That is, the shaft through-hole 34 is an opening (on the actuator side of the two valve plates 31, 32) from the opening on the actuator side of the axial portion 30 on the opposite side (tip side) to the actuator side of the axial portion 30. Are formed in a tapered hole shape that gradually decreases in diameter toward an elliptical curved surface on the opposite side (tip side).

Here, in the electronic throttle device of the present embodiment, a predetermined slide is provided between the tapered hole wall surface of the shaft through hole 34 of the axial direction portion 30 of the throttle valve 2 and the tapered guide surface of the valve guide 22 of the valve shaft 4. Has dynamic clearance. That is, between the tapered hole wall surface of the axial direction portion 30 and the tapered guide surface of the valve guide 22, the valve guide 22 can be smoothly rotated in the rotational direction within the shaft through hole 34 of the axial direction portion 30. In order to enable smooth movement in the axial direction (thrust direction), a predetermined sliding clearance is formed.
After the throttle valve 2 is incorporated in the air introduction flow path 15 of the housing 3, the valve guide 22 of the valve shaft 4 is inserted into the shaft through hole 34 in the air introduction flow path 15, so that the valve guide of the valve shaft 4 is inserted. 22 is slidably supported.
The outer diameter of the axial portion 30 of the throttle valve 2 is larger than the thickness of the two valve plates 31 and 32 in the plate thickness direction.

The throttle valve 2 has a spring engagement portion (first engagement portion) that engages the first end portion 36 on one side that is bent on the front side surface of the valve plate 31 so as to extend in the axial direction of the coil portion 35 of the coil spring 5. Stop portion) 41. Before the throttle valve 2 is assembled inside the air introduction flow path 15 of the housing 3 and before the valve shaft 4 is assembled to the throttle valve 2, the coil spring 5 is held by the spring holding portion 33 and the spring locking portion 41. Accordingly, it is possible to prevent the coil spring 5 from falling with respect to the throttle valve 2.
Further, the throttle valve 2 has a locked portion that is locked to the fully open stopper 19 when the throttle valve 2 is fully opened on the back side surface of the valve plate 31. Thus, when the locked portion of the valve plate 31 is locked by the full-open stopper 19 during the full-open operation, the throttle valve 2 is in a fully-open state in which the throttle valve 2 is fully opened. To be regulated.

Next, details of the valve shaft 4 of this embodiment will be described with reference to FIGS.
The valve shaft 4 constitutes a valve shaft of the EGRV, and has a first valve mounting portion that always connects (supports and fixes) the EGR valve 1 and a valve guide 22 that slidably supports the throttle valve 2. . The valve guide 22 is provided on the side opposite to the actuator side in the rotation axis direction of the valve shaft 4 (the other end side, the tip side in the rotation axis direction of the valve shaft 4).
The valve guide 22 is inserted so as to penetrate the shaft through hole 34 formed in the throttle valve 2 in the axial direction thereof. The valve guide 22 has a truncated conical shape in which the outer diameter gradually decreases from the actuator-side end of the valve guide 22 in the rotation axis direction toward the tip end of the valve guide 22 in the rotation axis direction. Is formed. That is, a tapered guide surface is formed on the outer periphery of the valve guide 22.

Further, a spring locking groove (second locking portion) 42 that locks the second terminal portion 37 on the other side of the coil spring 5 is provided between the first valve mounting portion of the valve shaft 4 and the valve guide 22. Is formed.
In addition, a fitting portion 43 having a two-surface width shape having two parallel planes and a convex curved surface is formed at an end portion (tip portion) opposite to the actuator side of the valve guide 22. The fitting portion 43 is closer to the actuator than the elliptical curved surface (the outer peripheral end surface perpendicular to both the front and back side surfaces of the two valve plates 31, 32) on the opposite side to the actuator side of the two valve plates 31, 32. On the other hand, it protrudes by the predetermined protrusion amount on the opposite side.

Next, details of the coil spring 5 of this embodiment will be described with reference to FIGS.
The coil spring 5 has a coil portion 35 installed so as to surround the outer periphery of the valve shaft 4 in the shaft circumferential direction. A part of the coil portion 35 (for example, one or two laps) is provided between the two first and second terminal portions 36 and 37 and is wound around the spring holding portion 33 of the throttle valve 2.
The coil spring 5 is a spring load that urges the throttle valve 2 toward the link lever in the direction of the rotation axis of the valve shaft 4 with respect to the throttle valve 2 (biasing force toward the link lever in the thrust direction: link lever side). A load applying means for applying a contact pressure). Accordingly, it is possible to stably secure a sliding clearance formed between the tapered hole wall surface of the shaft through hole 34 in the axial portion 30 of the throttle valve 2 and the tapered guide surface of the valve guide 22 of the valve shaft 4. it can.

  The coil spring 5 constitutes an urging torque applying means for applying an urging torque for urging the throttle valve 2 in the fully open direction (for example, the side pressed against the fully open stopper 19). The coil spring 5 is sandwiched between the spring locking portion 41 and the elliptical curved surface (44) of the throttle valve 2 and the spring locking groove 42 of the valve shaft 4 and the arc-shaped step surface 45 in a compressed and deformed state. In response to the load from the throttle valve 2 and the valve shaft 4, an urging torque is generated. This can improve the connection strength (engagement strength) of the throttle valve 2 and the valve shaft 4 during the second period, which will be described later. Therefore, it is possible to ensure the reliability of the valve drive mechanism (link mechanism) including the non-connected state between the valve shaft 4 and the valve shaft 4.

Next, details of the link lever 6 of this embodiment will be described with reference to FIGS. 1, 2, and 4. The link lever 6 is formed in a predetermined shape by press molding a metal plate or the like. The link lever 6 has an annular plate-shaped (plate-shaped) coupling portion (base plate) 51 that is fixed to the distal end portion of the valve shaft 4 in the rotation axis direction. The base plate 51 is fitted with a two-sided wide hole shape that fits into a fitting part 43 having a two-sided cross-sectional shape formed on the distal end side in the rotation axis direction of the valve shaft 4, particularly the distal end side of the valve guide 22. A joint hole 52 is formed.
Further, the link lever 6 is fixed to the tip end portion (fitting portion 43) of the valve shaft 4 in the rotational axis direction, and engages with the valve plate 32 of the throttle valve 2 in an L-shaped cross section. A portion 53 is provided. The engaging portion 53 is bent so that a plate-like protruding portion that protrudes in the radial direction from the outer periphery of the base plate 51 of the link lever 6, and the tip side of the protruding portion is along the rotational axis direction of the valve shaft 4. It has a plate-like extension part etc. extended along the rotation axis direction of the valve shaft 4. Moreover, the engaging part 53 has the bending part whose bending angle is a right angle between the protrusion part and the extension part. That is, the engaging portion 53 is a bent portion, and the distal end side of the protruding portion is bent at a right angle to the actuator side.
The protrusion angle of the engagement portion (protrusion portion) 53 with respect to the base plate 51 of the link lever 6 is set based on the flow rate characteristics of new intake air set in advance corresponding to the engine specifications or the vehicle type.

Here, the EGR valve 1 is always fixed to the first valve mounting portion of the valve shaft 4. For this reason, the link lever 6 opens / closes the throttle valve 2 (when the EGR valve 1 opens), when the EGR valve 1 opens / closes (especially when the EGR valve 1 opens). In particular, the timing for starting the closing operation of the throttle valve 2 (the timing for starting the closing operation of the throttle valve 2) is set based on the flow characteristics of the new intake air set in advance corresponding to the engine specifications or the vehicle type. The specified rotation angle (θ = 45 deg) can be delayed.
The link lever 6 constitutes a link that temporarily connects the throttle valve 2 to the valve shaft 4. Specifically, the link lever 6 is fixed to the distal end portion (fitting portion 43) of the valve shaft 4 in the rotation axis direction. Thus, when the rotation angle of the valve shaft 4 is changed from the minimum rotation angle (θ = 0 deg) to the specified rotation angle (θ = 45 deg) by the driving torque of the electric motor when the EGR valve 1 is fully opened, the link lever 6 Is engaged with the valve plate 32 of the throttle valve 2. That is, the engaging portion 53 of the link lever 6 contacts the valve plate 32 of the throttle valve 2 during the rotation angle range (second period) from the specified rotation angle to the maximum rotation angle (θ = 100 deg).

In addition, when the EGR valve 1 is fully closed, when the rotation angle of the valve shaft 4 reaches a specified rotation angle (θ = 45 deg) from a rotation angle (θ = 46 to 100 deg) larger than the specified rotation angle by the driving torque of the electric motor. The valve plate 31 of the throttle valve 2 is locked to the fully open stopper 19. When the rotation angle of the valve shaft 4 is changed from the specified rotation angle to a rotation angle smaller than the specified rotation angle when the EGR valve 1 is fully closed, the throttle valve 2 is stopped in the fully open state by the fully open stopper 19, so that the link lever 6 is disengaged from the valve plate 32 of the throttle valve 2.
Therefore, as shown in FIG. 5, the link lever 6 has a throttle valve during the first period until the rotation angle of the valve shaft 4 reaches the specified rotation angle (θ = 45 deg) from the minimum rotation angle (θ = 0 deg). The valve 2 and the valve shaft 4 are configured to be disconnected. Further, during the first period, the throttle valve 2 and the valve shaft 4 are disconnected from each other because the full opening operation of the throttle valve 2 is restricted by the full opening stopper 19. That is, during the first period, the interlocked state between the opening / closing operation (for example, valve opening operation) of the ERG valve 1 and the opening / closing operation (for example, valve closing operation) of the throttle valve 2 has been eliminated (the throttle valve 2 and the valve (Not connected to the shaft 4).

  The link lever 6 connects the throttle valve 2 and the valve shaft 4 during the second period until the rotation angle of the valve shaft 4 reaches the maximum rotation angle (θ = 100 deg) from the specified rotation angle (θ = 45 deg). It is comprised so that it may be in a connection state. Since the EGR valve 1 and the valve shaft 4 are always connected during the first period and the second period, that is, during the first period, only the EGR valve 1 is opened / closed by the driving torque of the electric motor. In addition, after the throttle valve 2 is installed inside the air introduction passage 15 of the housing 3, the valve guide 22 of the valve shaft 4 is inserted into the shaft through hole 34 in the air introduction passage 15, and the axial direction of the throttle valve 2 After projecting the fitting part 43 having a two-surface width, which is the tip of the valve shaft 4 in the rotational axis direction, from the part 30 or the elliptical curved surface, the link lever 6 is fitted to the fitting part 43 of the valve shaft 4, When the valve shaft 4 and the link lever 6 are fitted, the link lever 6 is fixed to the outer periphery of the fitting portion 43 using welding means such as laser welding.

[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.

  During engine idle operation, the amount of fuel injected to be supplied to each cylinder of the engine is small, so the exhaust gas temperature is low, the intake negative pressure is small, and the exhaust gas pressure is low. It is difficult to flow into the intake port. In such a case, electric power is supplied to the electric motor, the EGR valve 1 is fully opened in the valve opening operation direction using the driving torque of the electric motor, and the throttle valve 2 is fully closed in the valve closing operation direction. Let As a result, the EGR valve 1 is fully opened and the throttle valve 2 is fully closed.

  When the throttle valve 2 is set to the fully closed state, a gap formed between the flow wall surface of the air introduction flow path 15 of the housing 3 and the elliptic curved surfaces of the two valve plates 31 and 32 of the throttle valve 2. A small amount of new intake air passes through the intake port of each cylinder of the engine. Thereby, since the inflow of new intake air can be suppressed during idle operation in which the EGR gas hardly flows into the intake port of each cylinder of the engine, the inflow of EGR gas can be promoted. Therefore, the effect of reducing harmful substances (for example, nitrogen oxides: NOx, etc.) contained in the exhaust gas can be improved.

  Further, when the engine that requires high output is rotated at high speed and high load, the power supply to the electric motor is stopped, or the power supply to the electric motor is restricted, and the coil built in the housing 23 of the electric actuator An EGR valve using the biasing torque (spring load) of the spring and the biasing torque of the coil spring 5 having the coil portion 35 installed so as to surround the outer periphery of the valve shaft 4 in the circumferential direction of the shaft or the driving torque of the electric motor 1 is fully closed in the valve closing operation direction, and the throttle valve 2 is fully opened in the valve opening operation direction. As a result, the EGR valve 1 is fully closed and the throttle valve 2 is fully open, so that the recirculation of EGR gas to the combustion chamber and intake port of each cylinder of the engine is suppressed. As a result, only new intake air in which EGR gas is not mixed is sent to the combustion chamber of each cylinder of the engine, so that high output can be obtained.

  Here, when the EGR valve 1 is driven in the valve opening operation direction using the driving torque of the electric motor, first, the ECU sets a control target value (target) set in accordance with the engine operating state (engine information). The valve opening and the target rotation angle of the valve shaft 4 are calculated. Then, the electric motor is set so that the valve opening (rotation angle) of the EGR valve 1 matches the target valve opening, that is, the rotation angle of the valve shaft 4 that always connects the EGR valve 1 matches the target rotation angle. Supply power. When electric power is supplied to the electric motor, the motor shaft of the electric motor rotates in the valve opening operation direction of the EGR valve 1. Thereby, the drive torque of the electric motor is transmitted to the valve shaft 4 via a power transmission mechanism (for example, a gear reduction mechanism). Therefore, the valve shaft 4 rotates by a predetermined rotation angle in the valve opening operation direction of the EGR valve 1 with the rotation of the motor shaft of the electric motor.

  Here, during the first period until the rotation angle of the valve shaft 4 reaches the specified rotation angle (θ = 45 deg) from the minimum rotation angle (θ = 0 deg), the link lever 6 fixed to the valve shaft 4 is engaged. The joint portion 53 is not in contact with the valve plate 32 of the throttle valve 2, so that the throttle valve 2 and the valve shaft 4 are disconnected. The EGR valve 1 is always connected to the valve shaft 4. Thus, during normal running of a vehicle such as an automobile (rotational angle range changed based on the flow rate characteristic of new intake air set corresponding to the engine specification or vehicle type: θ = 0 to 45 deg), the valve As the shaft 4 rotates, the driving torque of the electric motor is transmitted from the valve shaft 4 only to the EGR valve 1, so that the EGR valve 1 rotates in the valve opening operation direction.

Therefore, EGR gas is mixed into new intake air (clean air) flowing through the merge chamber 16 and the air outlet passage 17 of the intake duct 12 of the housing 3 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.
In FIG. 5, the total flow is the total of the flow rate characteristic (Air flow) of the clean air with respect to the change in the rotation angle of the valve shaft 4 and the flow rate characteristic (EGR flow) of the EGR gas with respect to the change in the rotation angle of the valve shaft 4. The flow characteristics of

Further, during the first period when the EGR valve 1 is opened, the engaging portion 53 of the link lever 6 fixed to the valve shaft 4 is separated from the valve plate 32 of the throttle valve 2, and the throttle valve 2 and the valve The shaft 4 is not connected. That is, during normal running of a vehicle such as an automobile, the valve plate 31 of the throttle valve 2 is pressed against the fully open stopper 19 by the biasing torque of the coil spring 5, so that the throttle valve 2 does not rotate in the valve closing operation direction and is fully opened. Maintain state (initial state).
Further, during the first period, that is, during normal running of a vehicle such as an automobile, as shown in FIGS. 2 and 5, even if the valve shaft 4 rotates, the throttle valve 2 is maintained in a fully opened state. A dead zone (0 to 45 deg: indicated by a solid line in FIG. 5) in which the flow rate of new intake air (clean air) passing through the introduction flow path 15 does not change is formed.

  As a result, during the first period (range during normal running of a vehicle such as an automobile), it passes from the intake passage on the upstream side of the throttle valve 2 through the air introduction passage 15 around the throttle valve 2 and from the throttle valve 2. Also, the new intake air flow toward the intake passage on the downstream side (including the merging chamber 16 and the air outlet passage 17) is not disturbed, and the outer shape of the axial direction portion 30 of the throttle valve 2 and the valve guide 22 of the valve shaft 4 is reduced. Flows smoothly along. Therefore, since the intake resistance in the intake air passage (intake passage of the internal combustion engine) during normal running of a vehicle such as an automobile can be reduced, fuel consumption can be prevented from deteriorating.

  Here, during the second period until the rotation angle of the valve shaft 4 reaches the specified rotation angle (θ = 45 deg) and further reaches the maximum rotation angle (θ = 100 deg) from the specified rotation angle (θ = 45 deg). The engaging portion 53 of the link lever 6 fixed to the valve shaft 4 comes into contact with and engages with the valve plate 32 of the throttle valve 2, and the throttle valve 2 and the valve shaft 4 are connected. As a result, during the second period when the EGR valve 1 is opened, the drive torque of the electric motor is transmitted from the valve shaft 4 to both the EGR valve 1 and the throttle valve 2 as the valve shaft 4 rotates. The EGR valve 1 rotates in the valve opening operation direction, and the throttle valve 2 rotates in the valve closing operation direction.

  Therefore, during the second period, the valve closing operation of the throttle valve 2 is linked to the valve opening operation of the EGR valve 1. Further, since the engaging portion 53 of the link lever 6 fixed to the valve shaft 4 is configured to be detachably engaged with the valve plate 32 of the throttle valve 2, the valve opening operation of the EGR valve 1 is performed. Is a predetermined rotation angle (determined based on a flow characteristic of new intake air that is set in advance according to the engine specifications or the vehicle type. It can be delayed by θ = 45 deg).

Here, when the EGR valve 1 is fully closed in the valve closing operation direction from the valve open state (the valve open state where the valve is opened at a rotation angle larger than the specified rotation angle), the electric power supplied to the electric motor is By controlling, the rotation angle of the valve shaft 4 is changed from a rotation angle (including the maximum rotation angle) larger than the specified rotation angle to a minimum rotation angle (θ = 0 deg) smaller than the specified rotation angle. At this time, the supply of electric power to the electric motor is stopped, and the valve shaft 4 is rotated using the biasing force (spring load) of the coil spring and the biasing torque of the coil spring 5 built in the housing 23 of the electric actuator. The angle may be returned to the minimum rotation angle (θ = 0 deg).
During the second period when the EGR valve 1 is fully closed, the valve plate 32 of the throttle valve 2 is pressed against the engaging portion 53 of the link lever 6 fixed to the valve shaft 4 by the biasing torque of the coil spring 5. Therefore, the fully open operation of the throttle valve 2 is interlocked with the fully closed operation of the EGR valve 1.

When the rotation angle of the valve shaft 4 is returned to the specified rotation angle (θ = 45 deg), the valve plate 31 of the throttle valve 2 comes into contact with the fully open stopper 19. Thereby, the fully opening operation of the throttle valve 2 is completed.
When the EGR valve 1 is fully closed, the valve plate 31 of the throttle valve 2 is moved from the second period to the first period, that is, when the rotation angle of the valve shaft 4 is returned to a rotation angle smaller than the specified rotation angle. Is locked by the full-open stopper 19 and the full-opening operation of the throttle valve 2 is restricted, so that the engaging portion 53 of the link lever 6 fixed to the valve shaft 4 is disengaged from the valve plate 32 of the throttle valve 2 and EGR Only the valve 1 is fully closed in the valve closing operation direction. When the rotation angle of the valve shaft 4 reaches the minimum rotation angle (θ = 0 deg), the EGR valve 1 is fully closed.

[Features of Example 1]
In the EGR valve module incorporated in the EGR system of the present embodiment, as shown in FIG. 1, the air introduction flow path (throttle bore) 15 of the intake introduction duct 12 of the housing 3 is formed in a circular cross section. The throttle valve 2 accommodated in the air introduction channel 15 so as to be freely opened and closed (rotatable) is formed in an elliptical shape different from the cross-sectional shape of the air introduction channel 15.
Here, when the specifications of the internal combustion engine (engine) (displacement or flow rate characteristics of new intake air) or vehicle types are different, the diameter of the air introduction passage 15 of the intake introduction duct 12 of the housing 3 and the throttle valve 2 It is desirable to change the profile, the valve shaft 4, the link lever 6, the electric actuator, and the like to correspond to different engine specifications or vehicle types.

However, when the engine specifications or vehicle types are different, there is a demand for cost reduction by using some of the parts composing the EGR valve module in common. In particular, when the flow rate characteristic of new intake air with respect to the rotation angle of the valve shaft 4 is changed according to a user's request, there is a demand for cost reduction corresponding to the user's request by changing only some parts.
The profiles of the two valve plates 31 and 32 are changed according to the cross-sectional shape of the air introduction channel 15 and the channel diameter.
Therefore, in the EGR valve module of the present embodiment, when the engine specification or the vehicle type is different, the flow rate characteristic of the new intake air with respect to the rotation angle of the valve shaft 4 (that is, the value of the specified rotation angle with respect to the rotation angle of the valve shaft 4). When the engine is changed in accordance with the engine specifications or the vehicle type, the profile of the two valve plates 31 and 32 of the throttle valve 2, particularly the two valve plates is used for the purpose of reducing the cost by using some parts in common. The ellipticities 31 and 32 are changed based on the flow characteristics of the new intake air set in accordance with the engine specifications or the vehicle type.

  Here, in FIGS. 6A and 7A, when the rotation angle of the valve shaft 4 is a specified rotation angle (θ = 30 deg), the engaging portion 53 of the link lever 6 fixed to the valve shaft 4 is shown. Throttle valve 2 when the valve plate 32 of the throttle valve 2 is brought into contact with and engaged, and the opening / closing operation (valve closing operation) of the EGR valve 1 is linked to the opening / closing operation (valve closing operation) of the throttle valve 2. It is the figure which showed the protrusion angle of the engaging part (protrusion part) 53 with respect to the base plate 51 of the profile (contour) of the valve plates 31 and 32, and the link lever 6. FIG.

  The profile of the two valve plates 31 and 32 of the throttle valve 2 shown in FIG. 6A is based on the flow characteristics (set value of the specified rotation angle) of the new intake air set according to the engine specifications or vehicle type. It is decided based on. That is, the profiles of the two valve plates 31 and 32 of the throttle valve 2 are particularly short so that the ellipticity of the two valve plates 31 and 32 is smaller than the specified rotational angle θ = 45 deg. It has an elliptical shape so that the ratio of the major axis to the diameter is small.

  Further, the throttle valve 2 and the link lever 6 shown in FIGS. 6A and 7A are fitted to the fitting portion of the valve shaft 4 when the rotation angle of the valve shaft 4 is a specified rotation angle (θ = 30 deg). The engaging portion 53 of the link lever 6 fixed to 43 is brought into contact with and engaged with the valve plate 32 of the throttle valve 2. In this case, the air introduction flow path 15 can be fully opened over the entire normal travel corresponding to the rotation angle range of 0 to 30 deg. Thereby, the flow characteristic of the new intake air set according to the engine specifications or the vehicle type can be obtained without changing the flow path diameter of the air introduction flow path 15 of the intake air introduction duct 12 of the housing 3.

  6B and 7B show that the engaging portion 53 of the link lever 6 fixed to the valve shaft 4 is throttled when the rotation angle of the valve shaft 4 is a specified rotation angle (θ = 45 deg). When the opening / closing operation (valve closing operation) of the throttle valve 2 is linked to the opening / closing operation (valve opening operation) of the EGR valve 1 in contact with and engaged with the valve plate 32 of the valve 2, It is the figure which showed the protrusion angle of the profile (contour) of the valve plates 31 and 32, and the engaging part (protrusion part) 53 with respect to the base plate 51 of the link lever 6. FIG.

  The profile of the two valve plates 31 and 32 of the throttle valve 2 shown in FIG. 6B is based on the flow characteristics of the new intake air (set value of the specified rotation angle) set according to the engine specifications or vehicle type. It is decided based on. That is, the profile of the two valve plates 31 and 32 of the throttle valve 2 is such that the ellipticity of the two valve plates 31 and 32 is particularly short so that the specified rotation angle is larger than that of θ = 30 deg. It has an elliptical shape that increases the ratio of the major axis to the diameter.

  The throttle valve 2 and the link lever 6 shown in FIG. 6B and FIG. 7B are fitted to the fitting portion 43 of the valve shaft 4 when the rotation angle of the valve shaft 4 is a specified rotation angle (θ = 45 deg). The fixed engaging portion 53 of the link lever 6 contacts and engages the valve plate 32 of the throttle valve 2. In this case, the air introduction flow path 15 can be fully opened over the entire normal travel corresponding to the rotation angle range of 0 to 45 deg. Thereby, the flow characteristic of the new intake air set according to the engine specifications or the vehicle type can be obtained without changing the flow path diameter of the air introduction flow path 15 of the intake air introduction duct 12 of the housing 3.

  6 (c) and 7 (c) show that the engaging portion 53 of the link lever 6 fixed to the valve shaft 4 is throttled when the rotation angle of the valve shaft 4 is a specified rotation angle (θ = 60 deg). When the opening / closing operation (valve closing operation) of the throttle valve 2 is linked to the opening / closing operation (valve opening operation) of the EGR valve 1 in contact with and engaged with the valve plate 32 of the valve 2, It is the figure which showed the protrusion angle of the profile (contour) of the valve plates 31 and 32, and the engaging part (protrusion part) 53 with respect to the base plate 51 of the link lever 6. FIG.

  The profile of the two valve plates 31 and 32 of the throttle valve 2 shown in FIG. 6C is based on the flow characteristics of the new intake air (set value of the specified rotation angle) set according to the engine specifications or vehicle type. It is decided based on. That is, the profile of the two valve plates 31 and 32 of the throttle valve 2 is such that the ellipticity of the two valve plates 31 and 32 is particularly short so that the specified rotation angle is larger than θ = 45 deg. It has an elliptical shape that increases the ratio of the major axis to the diameter.

  The throttle valve 2 and the link lever 6 shown in FIGS. 6 (c) and 7 (c) are fitted to the fitting portion 43 of the valve shaft 4 when the rotation angle of the valve shaft 4 is a specified rotation angle (θ = 60 deg). The fixed engaging portion 53 of the link lever 6 contacts and engages the valve plate 32 of the throttle valve 2. In this case, the air introduction flow path 15 can be fully opened over the entire normal travel corresponding to a rotation angle range of 0 to 60 deg. Thereby, the flow characteristic of the new intake air set according to the engine specifications or the vehicle type can be obtained without changing the flow path diameter of the air introduction flow path 15 of the intake air introduction duct 12 of the housing 3.

  As described above, in the EGR valve module of the present embodiment, the profile (contour) of the two valve plates 31 and 32 of the throttle valve 2, particularly the ellipticity of the two valve plates 31 and 32, the engine specifications or the vehicle type It is changed based on the flow rate characteristics of the new intake air set corresponding to the above. In other words, when there is a request to change the flow rate characteristics of the new intake air in accordance with the engine specifications or the vehicle type, the profiles of the two valve plates 31 and 32 of the throttle valve 2, particularly the ellipses of the two valve plates 31 and 32. And the mounting angle of the link lever 6 with respect to the valve shaft 4 or the protruding angle (protruding direction) of the engaging portion (protruding portion) 53 with respect to the base plate 51 of the link lever 6 is changed for each engine specification or vehicle type. .

Thus, without changing the diameter of the air introduction passage 15 of the intake introduction duct 12 of the housing 3 (cross sectional shape of the throttle bore), that is, without changing the shape of the intake introduction duct 12 of the housing 3, The flow rate characteristic of the new intake air with respect to the rotation angle of the valve shaft 4 (that is, the value of the specified rotation angle with respect to the rotation angle of the valve shaft 4: for example, θ = 30 deg to 45 deg to 60 deg) may be changed according to the specification or the vehicle type. It becomes possible.
Here, in FIG. 5, the flow characteristic (Air flow) of the new intake air when the specified rotation angle is θ = 30 deg is shown by a one-dot chain line, and the flow characteristic (Air) of the new intake air when the specified rotation angle is θ = 45 deg. flow) and the total flow rate characteristic (Total flow) of the new intake air and the EGR gas are shown by a solid line, and the flow rate characteristic (Air flow) of the new intake air and the new intake air and EGR when the specified rotation angle is θ = 60 deg. A flow rate characteristic (total flow) totaled with gas is indicated by a broken line.

Accordingly, the start timing of the opening / closing operation (valve closing operation) of the throttle valve 2 with respect to the rotation angle of the valve shaft 4 can be changed without changing the shape of the intake air introduction duct 12 of the housing 3, so that the EGR valve module is configured. Some parts (housing 3, EGR valve 1, valve shaft 4, electric actuator, etc.) can be used in common among all parts, and cost reduction can be achieved. In addition, by changing only some of the components that make up the EGR valve module (profiles of the two valve plates 31, 32 of the throttle valve 2 and link lever 6), it can be adapted to different engine specifications or vehicle types. As a result, costs can be reduced. In addition, since the value of the specified rotation angle that defines the flow rate characteristics of the new intake air with respect to the rotation angle of the EGR valve 1 and the valve shaft 4 can be easily changed according to different engine specifications or vehicle types, the EGR valve 1 and the valve The degree of freedom in setting the flow rate characteristics of the new intake air with respect to the rotation angle of the shaft 4 can be improved.
In the EGR valve module of this embodiment, when the flow rate characteristic of the new intake air with respect to the rotation angle of the valve shaft 4 (that is, the value of the specified rotation angle with respect to the rotation angle of the valve shaft 4) is changed, 2 of the throttle valve 2 is used. The profile of the two valve plates 31, 32, particularly the ellipticity of the two valve plates 31, 32, is changed, and the mounting angle of the link lever 6 with respect to the valve shaft 4 or the protrusion of the engaging portion 53 with respect to the base plate 51 of the link lever 6 The direction (or the protruding angle of the engaging portion (projecting portion) 53 of the link lever 6 with respect to the base plate 51) is changed.

Here, in the EGR valve module of the present embodiment, the link lever 6 is fixed to the distal end portion of the valve shaft 4 in the rotational axis direction, and the fitting portion having a non-circular cross section is attached to the distal end portion of the valve shaft 4 in the rotational axis direction. 43, and further provided with a non-circular fitting hole 52 that fits in the fitting portion 43 in the link lever 6, and further prevents relative rotation between the fitting portion 43 of the valve shaft 4 and the link lever 6. As the rotation preventing means, a cross-sectional two-surface width shape and a two-surface width hole shape are used.
In such a case, the direction of the fitting hole 52 in the link lever 6 (for example, the direction of the straight portion having a two-surface width) corresponds to the flow rate characteristics of the new intake air with respect to the engine specification or vehicle type, or the rotation angle of the valve shaft 4. Thus, the attachment angle of the link lever 6 with respect to the fitting portion 43 of the valve shaft 4 can be changed. In the case of this method, the protruding direction of the engaging portion 53 with respect to the base plate 51 of the link lever 6 (or the protruding angle of the engaging portion (projecting portion) 53 with respect to the base plate 51 of the link lever 6) may not be changed. In this case, after the plate component having the link lever 6 and the engaging portion 53 is manufactured, the fitting hole 52 is drilled and the engaging portion 53 is bent.

[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 EGR duct 11 of the housing 3 connected to the downstream end of the EGR duct is connected to a part of the intake duct. Are connected at an acute angle to the intake air intake duct 12 (V-shaped connection). That is, in the EGR valve module of the present embodiment, the merging angle between the EGR flow path 14 formed in the EGR duct 11 and the air introduction flow path 15 formed in the intake air introduction duct 12 is an angle smaller than 90 degrees. (Acute angle) is set.
Thereby, the flow path resistance resulting from the bending of the EGR flow path 14 in the downstream portion of the EGR flow path 14 can be reduced. For this reason, an increase in flow path resistance due to the bending of the EGR flow path 14 can be suppressed, so that the flow rate of EGR gas (EGR amount: new intake) from the EGR flow path 14 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.

A throttle valve 2 having oval valve plates 31 and 32 on the same axis as the valve shaft 4 that supports and fixes the EGR valve 1 of the EGRV is slidably disposed on the valve shaft 4. That is, since the EGR valve 1 and the throttle valve 2 are arranged on the same axis line in the rotation axis direction (shaft axis direction) of the common valve shaft 4, the physique of the entire EGR valve module can be reduced in size. This makes it easy to secure a mounting space. In addition, since the electric actuator that drives the EGR valve 1 and the throttle valve 2 can be shared and the valve shaft 4 can be shared, the number of parts can be reduced and the cost can be reduced.
In addition, the merging angle between the EGR flow path 14 formed in the EGR duct 11 and the air introduction flow path 15 formed in the intake air introduction duct 12 is set to an angle (acute angle) smaller than 90 degrees. The valve shaft 4 is inserted (assembled) into the air introduction flow path 15 of the housing 3 so as to be inclined with respect to an axial direction (center axial direction) passing through the center of the air introduction flow path 15 of the housing 3.

  Further, the EGR valve 1 and the throttle valve 2 are arranged coaxially, and the rotation angle of the valve shaft 4 that transmits the drive torque of the electric motor to the EGR valve 1 and the throttle valve 2 is from the minimum rotation angle (θ = 0 deg). During the first period (period during normal running of a vehicle such as an automobile) until the specified rotational angle (θ = 30 deg, 45 deg or 60 deg) is reached, the engaging portion 53 of the link lever 6 fixed to the valve shut 4 is Since the throttle valve 2 is away from the valve plate 32, the throttle valve 2 and the valve shut 4 are disconnected. That is, during the first period (period during normal running of a vehicle such as an automobile), the EGR valve 1 opens from the fully closed state (initial state) in which the EGR flow path 14 is fully closed as the valve shaft 4 rotates. While the valve opening operation is performed in the operating direction, the throttle valve 2 is maintained in the fully open state (initial state).

Further, during the second period until the rotation angle of the valve shaft 4 reaches the maximum rotation angle (θ = 100 deg) from the specified rotation angle (θ = 30 deg, 45 deg or 60 deg), the link lever 6 fixed to the valve shut 4 Is engaged with the valve plate 32 of the throttle valve 2 so that the throttle valve 2 and the valve shut 4 are connected to each other. That is, only in the second period, the opening / closing operation (for example, valve closing operation) of the throttle valve 2 is linked to the opening / closing operation (for example, valve opening operation) of the EGR valve 1.
As a result, during the first period (period during normal running of a vehicle such as an automobile), the opening operation of the EGR valve 1 is started, but the closing operation of the throttle valve 2 is not started. A new intake air flow from the upstream intake passage through the air introduction passage 15 around the throttle valve 2 to the intake passage (including the merge chamber 16 and the air outlet passage 17) downstream from the throttle valve 2 is generated. It flows smoothly along the outer shape of the axial portion 30 of the throttle valve 2 and the valve guide 22 of the valve shaft 4 without being disturbed. Therefore, since the intake resistance in the intake air passage (intake passage of the internal combustion engine) during normal running of a vehicle such as an automobile can be reduced, fuel consumption can be prevented from deteriorating.

  Further, in the EGR valve module of the present embodiment, after the throttle valve 2 is incorporated into the air introduction passage 15 of the housing 3, the valve shaft 4 is passed through the axial hole 18 from the EGR passage 14 side of the housing 3. The link lever 6 is fitted into the outer periphery of the distal end portion (fitting portion 43) in the rotational axis direction of the valve shaft 4 which is inserted into the shaft through hole 34 of the axial portion 30 of the throttle valve 2 and protrudes from the throttle valve 2. 3, the link lever 6 is fixed to the fitting portion 43 of the valve shaft 4 using welding means such as laser welding, so that the throttle valve 2 and the link lever 6 are attached to the valve shaft 4. It is configured to be assembled.

Here, as in Comparative Example 1 shown in FIG. 11, when the valve shaft 202 of the actuator 201 is assembled to be inclined with respect to the axial direction of the intake air flow path 204 of the duct 203, the EGR valve 205 is opened and closed. It is difficult to fix a fastening member (screw) 207 such as a screw that fastens and fixes the throttle valve 206 that opens and closes the intake air flow path 204 in conjunction with the operation to the valve shaft 202. This is because the driver (tool) does not enter from the outside of the duct 203 perpendicular to the axial direction of the valve shaft 202.
Therefore, in the EGR valve module of the present embodiment, the valve guide 22 of the valve shaft 4 is formed in a truncated cone shape (tapered shape) for the purpose of improving the workability of assembling the throttle valve 2 and the valve shaft 4. The shaft through hole 34 of the throttle valve 2 is formed in a tapered hole shape corresponding to the truncated cone shape (tapered shape) of the valve guide 22.

As a result, when the valve guide 22 of the valve shaft 4 is inserted into the shaft through hole 34 of the throttle valve 2, the valve guide 22 having the tapered guide surface formed on the outer periphery is pivoted from the EGR flow path 14 side of the housing 3. It can be smoothly inserted into the shaft through hole 34 of the throttle valve 2 through the direction hole 18 without being caught by the wall surface of the tapered hole of the shaft through hole 34 of the throttle valve 2.
Therefore, even an EGR valve module in which the valve shaft 4 is assembled obliquely with respect to the axial direction (intake flow direction) of the air introduction flow path 15 of the housing 3 is incorporated into the air introduction flow path 15 of the housing 3. Further, the valve shaft 4 can be easily assembled to the shaft through hole 34 of the throttle valve 2.

FIG. 8 shows Example 2 of the present invention and is a diagram showing an example of changing the profile of the throttle valve.
In the electronic throttle device incorporated in the EGR valve module of this embodiment, the air introduction flow path (throttle bore) 15 of the intake introduction duct 12 of the housing 3 is formed in a circular cross section. Further, the throttle valve 2 accommodated in the air introduction channel 15 so as to be freely opened and closed (rotatable) is formed in an elliptical shape different from the cross-sectional shape of the air introduction channel 15.
Further, in this embodiment, the rotation angle range (the rotation angle range of the valve shaft 4) during regular running of a vehicle such as an automobile is set to a range of 0 to 55 deg. For this reason, the profiles of the two valve plates 31 and 32 of the throttle valve 2 have an elliptical shape such that the specified rotational angle is greater in ellipticity than θ = 45 deg, that is, the ratio of the major axis to the minor axis is large. It has become.

FIG. 9 shows a third embodiment of the present invention, FIG. 9A shows a link lever, and FIG. 9B shows an electronic throttle device.
In the electronic throttle device incorporated in the EGR valve module of the present embodiment, the major axis direction of the air introduction flow path (throttle bore) 15 of the intake introduction duct 12 of the housing 3 is formed in an elliptical cross section in the horizontal direction shown in the drawing. Further, the throttle valve 2 accommodated in the air introduction channel 15 so as to be freely opened and closed (rotatable) is formed in an elliptical shape different from the cross-sectional shape of the air introduction channel 15. Further, in this embodiment, the rotation angle range (the rotation angle range of the valve shaft 4) during regular running of a vehicle such as an automobile is set to a range of 0 to 45 degrees. For this reason, the protruding direction of the engaging portion 53 with respect to the base plate 51 of the link lever 6 (or the protruding angle of the engaging portion (projecting portion) 53 with respect to the base plate 51 of the link lever 6) is 45 degrees.

FIG. 10 shows a fourth embodiment of the present invention, and FIGS. 10A and 10B show an electronic throttle device.
In the electronic throttle device incorporated in the EGR valve module of this embodiment, as shown in FIG. 10A, the air introduction flow path (throttle bore) 15 of the intake introduction duct 12 of the housing 3 is formed in a rectangular cross section. Yes. Further, the throttle valve 2 accommodated in the air introduction channel 15 so as to be openable and closable (rotatable) is formed in a quadrangular shape (for example, a parallelogram shape) different from the cross-sectional shape of the air introduction channel 15. In the present embodiment, the protruding direction of the engaging portion 53 with respect to the base plate 51 of the link lever 6 (or the protruding angle of the engaging portion (protruding portion) 53 with respect to the base plate 51 of the link lever 6) is 30 deg to 45 deg to 60 deg. It is optional at home.

  Further, in the electronic throttle device of this embodiment, as shown in FIG. 10B, the major axis direction of the air introduction flow path (throttle bore) 15 of the intake introduction duct 12 of the housing 3 is an elliptical section in the vertical direction shown in the figure. It is formed into a shape. Further, the throttle valve 2 accommodated in the air introduction channel 15 so as to be freely opened and closed (rotatable) is formed in an elliptical shape different from the cross-sectional shape of the air introduction channel 15. In the present embodiment, the protruding direction of the engaging portion 53 with respect to the base plate 51 of the link lever 6 (or the protruding angle of the engaging portion (protruding portion) 53 with respect to the base plate 51 of the link lever 6) is 30 deg to 45 deg to 60 deg. It is optional at home.

[Modification]
In this embodiment, the nozzle 13 is fitted and held on the inner periphery of the nozzle fitting portion of the housing 3, and the EGR valve 1 is housed in the nozzle 13 so as to be freely opened and closed. The EGR valve 1 may be accommodated in the unit so as to be freely opened and closed. In this case, the nozzle 13 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 1 in the valve closing operation direction or the valve opening operation direction. In this case, the number of parts and assembly man-hours can be reduced.

In this embodiment, the rotation angle of the valve shaft 4 (or the rotation angle of the EGR valve 1 supported and fixed to the valve shaft 4) is set to a minimum rotation angle (for example, θ = 0 deg) and a maximum rotation angle (for example, θ = 100 deg). The actuator that is variable between the two is configured by an electric actuator including an electric motor and a power transmission mechanism (for example, a gear reduction mechanism), but the rotation angle of the valve shaft 4 (or the EGR valve 1 supported and fixed to the valve shaft 4). Actuators that vary the minimum rotation angle between the minimum rotation angle and the maximum rotation angle, such as a negative pressure actuated actuator with an electromagnetic or electric negative pressure control valve, or an electromagnetic actuator with an electromagnet including a coil You may comprise by.
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 bearings (ball bearings) 8 and 9 are adopted as bearing members. However, as bearing members, sintered bearings, resin bearings, sliding bearings, rolling bearings, needle bearings, metal bearings, and the like are used. May be used.
In this embodiment, a thermoplastic resin is used as a synthetic resin material for molding the throttle valve 2, but a thermosetting resin such as unsaturated polyester (UP) is used as the synthetic resin material for molding the throttle valve 2. It may be adopted. The throttle valve 2 may be formed of a metal material.
Further, an aluminum alloy or a magnesium alloy may be used as a metal material for forming the housing 3 and the throttle valve 2.

Further, the first period (automobile) until the rotation angle of the shaft driving the two first and second valves (or the rotation angle of the first valve supported and fixed to the shaft) reaches the specified rotation angle from the minimum rotation angle. The range during normal travel of the vehicle is arbitrarily changed based on the flow characteristics of the new intake air set corresponding to the specifications of the internal combustion engine or the vehicle type, for example, within a rotation angle range of 0 deg to 90 deg. May be.
Further, the second period until the rotation angle of the shaft driving the two first and second valves (or the rotation angle of the first valve supported and fixed to the shaft) reaches the maximum rotation angle from the specified rotation angle, For example, the rotation angle range of 10 deg to 100 deg may be arbitrarily changed based on the flow rate characteristics of the new intake air set corresponding to the specifications of the internal combustion engine or the vehicle type.

It is the block diagram which showed the EGR valve module (Example 1). (A) is explanatory drawing which showed the operable range of a throttle valve, (b) is the top view which showed the link lever, (c) is the schematic which showed the electronic throttle device (Example 1). (A) is the exploded view which showed the assembly structure of the coil spring with respect to a throttle valve, (b) is the enlarged view which showed the spring latching groove of the shaft (Example 1). (A) is the exploded view which showed the assembly structure of the coil spring with respect to a throttle valve, (b) is explanatory drawing which showed the state which assembled | attached the coil spring to the throttle valve (Example 1). 6 is a graph showing a flow rate characteristic of new intake air (clean air) with respect to a shaft rotation angle, a flow rate characteristic of EGR gas, and a total flow rate characteristic obtained by adding new intake air and EGR gas (Example 1). (A)-(c) is the top view which showed the example of a change of the profile of a throttle valve (Example 1). (A)-(c) is explanatory drawing which showed the example of a change of the protrusion angle of the engaging part (protrusion part) with respect to the base plate of a link lever (Example 1). (Example 2) which is the perspective view which showed the example of a change of the profile of a throttle valve. (A) is the top view which showed the link lever, (b) is the schematic which showed the electronic throttle device (Example 3). (A), (b) is the schematic which showed the electronic throttle device (Example 4). It is the block diagram which showed the apparatus with which the shaft inclined and assembled | attached with respect to the axial direction of an intake air flow path (comparative example 1). 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 EGR valve (first valve)
2 Throttle valve (second valve)
3 Housing 4 Valve shaft 5 Coil spring (biasing torque applying means, load applying means)
6 Link lever (link)
7 Bearing 8 Bearing 11 EGR duct (first duct)
12 Intake inlet duct (second duct)
13 Nozzle (cylindrical part)
14 EGR flow path (exhaust gas passage)
15 Air introduction flow path (intake air passage, throttle bore)
16 Junction chamber (merging section of exhaust gas passage and intake air passage)
17 Air outlet flow path 19 Fully open stopper 22 Valve shaft valve guide 30 Throttle valve axial portion 31 Throttle valve valve plate (first valve plate)
32 Throttle valve valve plate (second valve plate)
33 Throttle valve spring holding part (protruding part)
34 Throttle valve shaft through hole 41 Throttle valve spring lock (first lock)
42 Spring locking groove of valve shaft (second locking part)
43 Valve shaft fitting part 51 Link lever base plate (joint part)
52 Link lever fitting hole 53 Link lever engaging part (lever part, protruding part)

Claims (13)

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) These two first and second valves are arranged coaxially, and a shaft for driving the two first and second valves;
(E) an actuator that changes the rotation angle of the shaft between a minimum rotation angle and a maximum rotation angle;
The merging angle between the exhaust gas passage and the intake air passage is set to an angle smaller than 90 degrees,
The shaft and the second valve are moved only during a period until the shaft reaches a maximum rotation angle from a specified rotation angle that is larger than the minimum rotation angle and smaller than the maximum rotation angle. An exhaust gas recirculation device having a link to be connected. The exhaust gas recirculation device according to claim 1,
The link disconnects the shaft and the second valve during a first period until the rotation angle of the shaft reaches the specified rotation angle from the minimum rotation angle, and the rotation of the shaft. The exhaust gas recirculation device is configured to connect the shaft and the second valve during a second period until the angle reaches the maximum rotation angle from the specified rotation angle. . The exhaust gas recirculation device according to claim 1 or 2,
The link is configured to delay the timing for starting the fully closing operation of the second valve by the specified rotation angle with respect to the timing for starting the fully opening operation of the first valve. Exhaust gas recirculation device. The exhaust gas recirculation device according to claim 3,
The exhaust gas recirculation device, wherein the housing has a fully open stopper that restricts a fully open state of the second valve. The exhaust gas recirculation device according to claim 4,
An exhaust gas recirculation apparatus comprising: an urging torque applying means for applying an urging torque for urging the second valve in a fully open direction with respect to the second valve. The exhaust gas recirculation device according to any one of claims 1 to 5,
The exhaust gas recirculation device according to claim 1, wherein the link 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 any one of claims 1 to 6,
The exhaust gas recirculation device, wherein the link has an engaging portion that is detachably engaged with the second valve. The exhaust gas recirculation device according to any one of claims 1 to 7,
The exhaust gas recirculation device, wherein the shaft slidably supports the second valve. The exhaust gas recirculation device according to any one of claims 1 to 8,
The shaft has a guide that slidably supports the second valve;
The second valve has a through hole extending in an axial direction of the shaft,
The exhaust gas recirculation device, wherein the guide is inserted so as to penetrate the through hole in the axial direction thereof. The exhaust gas recirculation device according to claim 9,
The guide is formed in a truncated cone shape whose outer diameter gradually decreases from an end on the actuator side in the axial direction of the shaft toward an end opposite to the actuator side in the axial direction of the shaft. And
The exhaust gas recirculation apparatus, wherein the through hole is formed in a tapered hole shape corresponding to a truncated cone shape of the guide. The exhaust gas recirculation device according to claim 10,
An exhaust gas recirculation apparatus, wherein a predetermined sliding clearance is formed between a tapered guide surface of the shaft and a tapered hole wall surface of the second valve. The exhaust gas recirculation device according to claim 11,
An exhaust gas recirculation device comprising load applying means for applying a load for urging the second valve to the side opposite to the actuator side in the axial direction of the shaft. The exhaust gas recirculation device according to any one of claims 1 to 12, wherein the housing has a duct in which a throttle bore corresponding to an intake air passage upstream of the merging portion is formed. And
The second valve has a valve plate having a shape different from a cross-sectional shape of the throttle bore,
The exhaust gas recirculation device according to claim 1, wherein the profile of the valve plate is changed based on a flow rate characteristic of intake air set in accordance with a specification or a vehicle type of the internal combustion engine.

Images