JP2006057552A - Air control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid the function degradation of a check valve 6 which prevents the blow of exhaust gas to the side of a solenoid valve 1 by preventing the clogging of a reed valve 7. <P>SOLUTION: In a case outlet 9 of the check valve 6, a hollow space 19 is provided where the flow of exhaust gas blown from an engine exhaust pipe into second air flow paths 16, 17 stagnates. An opening portion 54 of the hollow space 19 is opened to a flow path wall face 52 of a bent portion 51 opposed to the direction of the exhaust gas flowing from the engine exhaust pipe into the secondary air flow paths 16, 17. It is provided on the upstream side in the flowing-in direction of the exhaust gas beyond an opening/closing operation range of the reed valve 7 of the check valve 6. Thus, the flow of the exhaust gas flowing into the hollow space 19 stagnates in the hollow space 19 in front of an air tight plug 53, and so deposits are easily built up or accumulated in the hollow space 19 and hardly adhered to the reed valve 7 of the check valve 6. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an air control valve having a valve body that opens and closes an air passage communicating with an exhaust passage of an internal combustion engine, and particularly introduces secondary air pressure-fed and supplied from an air pump into an exhaust pipe of the internal combustion engine. Secondary air control valve provided with a solenoid valve that opens and closes a secondary air flow path for the engine and a check valve that prevents exhaust gas flowing out from the combustion chamber or exhaust pipe of the internal combustion engine from flowing back to the solenoid valve side Related to.

[Conventional technology]
Conventionally, when the engine is started, when the temperature of the exhaust gas flowing out from the combustion chamber of the internal combustion engine is low, the secondary air generated by operating the air pump is led to a three-way catalytic converter that purifies the exhaust gas. Secondary air supply devices are known which activate the catalyst. An electromagnetic secondary air control valve is installed in the secondary air passage for guiding the secondary air pressure-fed and supplied from the air pump to the three-way catalytic converter. As shown in FIG. 10, this electromagnetic secondary air control valve has an electromagnetic valve 102 that opens and closes the secondary air flow path 101, and exhaust gas that has flowed in from the exhaust pipe of the internal combustion engine flows backward to the electromagnetic valve 102 side. (See, for example, Patent Documents 1 and 2).

  The electromagnetic valve 102 includes a housing 104 that forms the secondary air flow path 101, a valve body (valve) 106 that opens and closes an opening (valve hole) 105 formed in the housing 104, and opens the valve 106. A solenoid actuator that is driven in the direction, a coil spring 107 that biases the valve 106 in the valve closing direction, and the like. The check valve 103 includes a case outlet 110 connected to the downstream end of the housing 104 of the electromagnetic valve 102, a reed valve 112 that opens and closes an air passage port 111 formed in the case outlet 110, and the reed valve 112. A lead stopper 113 that protects the exhaust gas, and the reed valve 112 prevents the exhaust gas from blowing back to protect the solenoid valve 102 from the heat of the exhaust gas and the exhaust gas containing particulate matter such as combustion residue and carbon. Is configured to do.

[Conventional technical problems]
However, in the conventional electromagnetic secondary air control valve, when the valve 106 of the electromagnetic valve 102 is closed, the exhaust pulsation caused by opening and closing of the exhaust valve of the internal combustion engine causes the inside of the case outlet 110 from the exhaust pipe of the internal combustion engine. The exhaust gas flows backward, and foreign matter such as fine particles contained in the exhaust gas adheres to the reed valve 112 of the check valve 103 to form a deposit. If the deposit enters between the reed valve 112 and the metal plate 114 when the reed valve 112 of the check valve 103 is opened, the reed valve 112 may be clogged. When the reed valve 112 of the check valve 103 is clogged in this way, the reed valve 112 is always kept open, and the check valve that prevents the exhaust gas from blowing back from the exhaust pipe of the internal combustion engine to the electromagnetic valve 102 side is prevented. The function as 103 is reduced. As a result, the exhaust gas flows backward to the housing 104 side of the electromagnetic valve 102, deposits adhere to the valve 106 of the electromagnetic valve 102, and deposit accumulates between the valve 106 and the housing 104. May become stuck (stick), or the valve 106 may not smoothly open and close. In this case, there is a problem that the flow rate of the secondary air pressure-fed and supplied from the air pump to the three-way catalytic converter is reduced, and the original function of activating the three-way catalyst is lost.

  Further, the exhaust gas recirculation gas (EGR gas), which is part of the exhaust gas flowing out from the combustion chamber of the internal combustion engine, is mixed into the intake air flowing through the intake pipe of the internal combustion engine, thereby reducing the maximum combustion temperature and There has been known an exhaust gas recirculation device designed to reduce harmful substances (for example, nitrogen oxides) contained in gas. An exhaust gas recirculation amount control valve (air flow control valve) is installed in the exhaust gas recirculation passage for guiding EGR gas from the exhaust pipe of the internal combustion engine to the intake pipe. The exhaust gas recirculation amount control valve includes a housing that forms an exhaust gas recirculation path, a valve body (valve) that adjusts the opening area of an opening (valve hole) provided in the middle of the exhaust gas recirculation path, and opens the valve. The motor actuator is driven in the direction, and the coil spring is used to bias the valve in the valve closing direction.

Here, the exhaust gas recirculation amount control valve is provided in an exhaust gas recirculation passage through which exhaust gas containing particulate matter such as combustion residues and carbon flows, and the particulates contained in the exhaust gas are contained in the valve. It adheres and forms a deposit (deposit). And when the valve is opened, if a deposit enters between the valve and the housing, and deposit accumulates between the valve and the housing, the valve is closed (stick) or the valve Smooth opening / closing operation may not be performed. In order to solve such problems, an exhaust gas recirculation amount control valve is known in which a lateral hole is provided on the passage wall surface of the housing on the exhaust pipe side of the valve before the deposit reaches the valve. (For example, see Patent Document 3). However, since the deposit that has flowed into the side hole, which is a dead end dead end, may bounce back and come out from the opening of the side hole into the exhaust gas recirculation path, the effect could not be expected so much.
JP 2002-272080 A (page 1-5, FIG. 1) JP 2002-260919 A (page 1-5, FIG. 1 to FIG. 3) JP 2002-339811 A (page 1-6, FIG. 1 to FIG. 3)

  An object of the present invention is to make a foreign matter such as fine particles contained in the exhaust gas blown back from the exhaust pipe of the internal combustion engine, or a foreign matter such as fine particles contained in the exhaust gas flowing out from the combustion chamber of the internal combustion engine, or the combustion chamber of the internal combustion engine. An object of the present invention is to provide an air control valve that can prevent foreign matters such as fine particles contained in the unburned gas flowing backward from adhering to the valve body to form a deposit. Further, it is possible to prevent the exhaust gas from being blown back by suppressing foreign matters such as fine particles contained in the exhaust gas flowing out from the combustion chamber or the exhaust pipe of the internal combustion engine from adhering to the check valve to form a deposit. An object of the present invention is to provide an air control valve capable of avoiding a decrease in function as a stop valve.

  According to the first aspect of the present invention, the tubular body is provided with a bent portion that bends the flow direction of the gas flowing into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine in a direction different from the valve body side, The bent portion is provided on the upstream side in the gas inflow direction from the opening / closing operation range of the valve body. As a result, the gas flow flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine stagnates in the vicinity of the bent portion, and the foreign matter contained in the gas flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine Tends to accumulate or accumulate near the bent portion. Therefore, the amount of foreign matter contained in the gas flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine can be reduced, and the gas flowing out from the combustion chamber or exhaust pipe of the internal combustion engine can be reduced. Foreign matter contained therein (for example, fine particles contained in exhaust gas or unburned gas) becomes difficult to adhere to or accumulate on the valve body. As a result, the valve element can be prevented from sticking closed (stick) and the valve element cannot be operated (or defective), so that a smooth opening / closing operation of the valve element can be ensured.

  According to the second aspect of the present invention, the bent portion is provided with the flow passage wall surface facing the inflow direction of the gas flowing into the air flow passage from the combustion chamber or the exhaust pipe of the internal combustion engine, and the flow passage of the bent portion is provided. In the vicinity of the wall surface, a stagnation space is provided in which a gas flow flowing into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine is swallowed. As a result, the gas flow that flows into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine stagnate in the stagnation space near the bent portion, and into the gas flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine. The contained foreign matter is easily accumulated or accumulated in the stagnation space. Therefore, the effect of the invention of claim 1 can be improved.

  According to the invention described in claim 3, a stagnation space is provided in the tubular body to entrain the gas flow flowing into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine, and at one end of the stagnation space, An opening is provided so as to be opposed to the inflow direction of the gas flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine, and the opening of the stagnation space is more than the opening / closing operation range of the valve body. It is provided on the upstream side in the inflow direction. As a result, the gas that has flowed into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine flows into the stagnation space through the opening, stagnate in the stagnation space, and foreign substances contained in the gas accumulate in the stagnation space. Or it becomes easy to accumulate. Therefore, the amount of foreign matter contained in the gas flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine can be reduced, and the gas flowing out from the combustion chamber or exhaust pipe of the internal combustion engine can be reduced. Foreign matter contained therein (for example, fine particles contained in exhaust gas or unburned gas) becomes difficult to adhere to or accumulate on the valve body. As a result, the valve element can be prevented from sticking closed (stick) and the valve element cannot be operated (or defective), so that a smooth opening / closing operation of the valve element can be ensured.

  According to the invention described in claim 4, the tubular body is provided with a bent portion that bends the flow direction of the gas flowing into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine in a direction different from the valve body side, The bent portion is provided with a flow passage wall surface facing the inflow direction of the gas flowing into the air flow passage from the combustion chamber or the exhaust pipe of the internal combustion engine, and the opening portion of the stagnation space is formed on the flow passage wall surface of the bent portion. Open. As a result, the gas that has flowed into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine flows into the stagnation space through the opening that is opened in the flow path wall surface of the bent portion, and stagnates in the stagnation space. The foreign matter contained in the water is easily accumulated or accumulated in the stagnation space. Therefore, the effect of the invention of claim 3 can be improved.

  According to the invention described in claim 5, when the gas flows into the stagnation space from the opening by making the opening area of the opening of the stagnation space smaller than the opening area on the back side of the stagnation space, Since the gas swirls or recirculates in the stagnation space, the flow rate of the gas that flows into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine decreases to the valve body side, so the gas flows from the combustion chamber or exhaust pipe of the internal combustion engine. The amount of foreign matter contained in the gas flowing into the air flow path that adheres to the valve body can be reduced. According to the invention described in claim 6, the foreign matter return portion for preventing the gas once flowing into the stagnation space from flowing out from the stagnation space to the valve body side is provided at the opening of the stagnation space. When the gas flows into the stagnation space from the opening, the gas swirls or recirculates in the stagnation space, so that the gas flow rate that flows into the valve body side from the combustion chamber or exhaust pipe of the internal combustion engine into the air flow path Therefore, the amount of foreign matter contained in the gas flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine can be reduced. Furthermore, according to the invention described in claim 7, it is desirable that the foreign matter return portion is provided on the valve body side of the opening portion of the stagnation space. When high-temperature gas flows into the stagnation space of the tubular body, the temperature rise around the tubular body, particularly the valve body, can be reduced by moving the stagnation space away from the valve body.

  According to the eighth aspect of the present invention, the tubular body is provided with an interference wall that prevents the flow of gas flowing from the combustion chamber or the exhaust pipe of the internal combustion engine into the air flow path toward the valve body, and the interference wall is provided with the interference wall. , Provided upstream of the valve opening / closing operation range in the gas inflow direction. As a result, the gas flow that has flowed into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine collides with the interference wall, stagnates in the vicinity of the interference wall, and flows into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine. Foreign substances contained in the gas are easily deposited or accumulated near the interference wall. Therefore, the amount of foreign matter contained in the gas flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine can be reduced, and the gas flowing out from the combustion chamber or exhaust pipe of the internal combustion engine can be reduced. Foreign matter contained therein (for example, fine particles contained in exhaust gas or unburned gas) becomes difficult to adhere to or accumulate on the valve body. As a result, the valve element can be prevented from sticking closed (stick) and the valve element cannot be operated (or defective), so that a smooth opening / closing operation of the valve element can be ensured.

  According to the ninth aspect of the present invention, the interference wall is provided with a wall surface facing the inflow direction of the gas flowing into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine, and in the vicinity of the wall surface of the interference wall In addition, a stagnation space is provided in which a gas flow flowing into the air flow path from the combustion chamber or the exhaust pipe of the internal combustion engine is stored. As a result, the gas flow that flows into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine stagnate in the stagnation space near the wall surface of the interference wall, and the gas that flows into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine Foreign matter contained therein is easily accumulated or accumulated in the stagnation space. Therefore, the effect of the invention of claim 8 can be improved.

  According to the invention described in claim 10, as the tubular body, an air flow path pipe connected to an exhaust pipe through which exhaust gas flowing out from the combustion chamber of the internal combustion engine flows may be provided. Further, as the air flow path, a secondary air flow path for introducing secondary air pressure-fed and supplied from the air pump into the exhaust system of the internal combustion engine may be provided. And it is possible to rectify the flow of the secondary air flowing into the secondary air flow path from the air pump to the flow path wall surface of the interference wall or the flow path wall surface of the air flow pipe and flowing toward the exhaust pipe. You may give it an inclination angle. Thereby, even when an interference wall is provided so as to protrude into the secondary air flow path, an increase in the pressure loss of the secondary air flow can be suppressed.

  According to the eleventh aspect of the present invention, an air flow path pipe connected to an exhaust pipe through which exhaust gas flowing out from the combustion chamber of the internal combustion engine flows may be provided as the tubular body. Further, as the air flow path, a secondary air flow path for introducing secondary air pressure-fed and supplied from the air pump into the exhaust system of the internal combustion engine may be provided. Moreover, you may provide the valve which opens and closes the secondary air flow path of an air flow path pipe as a valve body. That is, the air control valve of the present invention is applied to a secondary air supply device for introducing secondary air generated by operating an air pump into an exhaust system of an internal combustion engine, and secondary air in an air flow path pipe. You may employ | adopt for the secondary air control valve which opens and closes a flow path.

  According to the twelfth aspect of the present invention, the tubular body includes a check valve that prevents the exhaust gas flowing in the exhaust pipe from flowing back to the valve side closer to the exhaust pipe side than the opening / closing operation range of the valve. An outlet may be provided. The case outlet may be provided with a stagnation space in which an exhaust gas flow flowing from the exhaust pipe of the internal combustion engine into the air flow path is swallowed. In this case, foreign matter such as fine particles contained in the exhaust gas flowing out of the combustion chamber of the internal combustion engine and flowing in the exhaust pipe can be prevented from adhering and accumulating on the check valve. It is possible to prevent a decrease in the function as a check valve that reliably prevents the blow-back of the air.

  According to a thirteenth aspect of the present invention, the check valve includes a metal plate that forms an air passage through which secondary air passes, a reed valve that opens and closes the air passage, and an opening of the reed valve. You may comprise by the lead stopper etc. which regulate a condition. The stagnation space may be provided upstream of the check valve reed stopper, that is, the reed valve opening / closing operation range in the exhaust gas inflow direction. In this case, it is possible to prevent foreign matters such as fine particles contained in the exhaust gas flowing out from the combustion chamber of the internal combustion engine from adhering to and depositing on the reed valve of the check valve. This prevents the check valve's reed valve from becoming clogged, so the check valve's reed valve does not always remain open, and the check valve reliably prevents the exhaust gas from blowing back to the valve side. It is possible to prevent deterioration of the function as a valve.

  According to the fourteenth aspect of the present invention, an air flow path pipe (exhaust gas recirculation pipe) connected to an exhaust pipe through which exhaust gas flowing out from the combustion chamber of the internal combustion engine flows may be provided as the tubular body. An exhaust gas recirculation path for introducing a part of the exhaust gas flowing out from the combustion chamber of the internal combustion engine into the intake pipe of the internal combustion engine may be provided as the air flow path. Moreover, you may provide the valve which adjusts the exhaust gas recirculation amount which flows through the inside of the exhaust gas recirculation path of an air flow path pipe as a valve body. That is, the air control valve according to the present invention is provided with an exhaust gas recirculation provided with an air passage pipe (exhaust gas recirculation pipe) for recirculating a part of the exhaust gas flowing out from the combustion chamber of the internal combustion engine from the exhaust pipe to the intake pipe. You may employ | adopt for the exhaust gas recirculation amount control valve which controls the exhaust gas recirculation amount which flows through the inside of the exhaust gas recirculation path of an air flow path pipe | tube applied to a circulator.

  The best mode for carrying out the present invention is a foreign matter such as fine particles contained in the exhaust gas blown back from the exhaust pipe of the internal combustion engine, or a foreign matter such as fine particles contained in the exhaust gas flowing out from the combustion chamber of the internal combustion engine, Alternatively, the internal combustion engine has the purpose of preventing foreign matters such as fine particles contained in unburned gas flowing backward from the combustion chamber of the internal combustion engine from adhering to and accumulating on the valve body and causing the valve body to cause sticks and malfunctions. This was realized by providing a stagnation space for the gas flow flowing from the combustion chamber into the air flow path.

[Configuration of Example 1]
FIGS. 1 and 2 show Example 1 of the present invention, and FIGS. 1 and 2 are diagrams showing the overall configuration of an electromagnetic secondary air control valve.

  The secondary air supply apparatus according to the present embodiment includes an air pump (not shown) that generates secondary air, an electric motor (not shown) that rotationally drives the air pump, and secondary air that extends from the air pump to the engine exhaust pipe. A flow path pipe, and an electromagnetic secondary air control valve provided on the middle or outlet side of the secondary air flow path pipe for opening and closing the secondary air flow path for guiding the secondary air to the three-way catalytic converter; And an engine control unit (hereinafter referred to as ECU: not shown) that electronically controls the electric motor and the electromagnetic secondary air control valve based on the operating state of the engine.

  The electromagnetic secondary air control valve activates the three-way catalyst by guiding the secondary air generated by operating the air pump to the three-way catalytic converter when the exhaust gas temperature is low when starting the engine. The secondary air supply device is connected between a secondary air supply pipe (not shown) and an engine exhaust pipe (not shown). Here, the electromagnetic secondary air control valve of this embodiment uses secondary air pressure-fed and supplied from an air pump as an exhaust system (particularly, a three-way catalytic converter) of an internal combustion engine (hereinafter referred to as an engine) such as a gasoline engine. ), And a check valve 6 that allows air flow only in one direction and blocks air flow in the opposite direction.

  In the present embodiment, a generally circular valve housing 3 that accommodates a poppet-type valve (valve element) 2 of the electromagnetic valve 1 so as to be openable and closable, and a lead valve 7 and a lead stopper 8 of the check valve 6 are held. The tubular case outlet 9 constitutes a secondary air passage pipe (tubular body) that is directly connected to an engine exhaust pipe through which exhaust gas flowing out from the combustion chamber of the engine flows. Here, the ECU includes a CPU that performs control processing, arithmetic processing, various programs, memory (ROM, RAM) that stores data, an input circuit, an output circuit, a power supply circuit, and the like. A computer, a pump drive circuit (not shown) for energizing and controlling the electric motor of the air pump based on the operating state of the engine, and an electromagnetic valve drive circuit (not shown) for energizing and controlling the solenoid valve 1 based on the operating state of the engine Is provided. The solenoid valve drive circuit is configured to output a solenoid valve drive current to the solenoid valve 1.

  The electromagnetic valve 1 integrally couples a poppet type valve 2 that opens and closes the secondary air flow paths 11 and 12 and a case outlet 9 of the check valve 6, and an air passage port 13 through which secondary air passes. , A solenoid actuator 4 for driving the poppet type valve 2 in the valve opening direction, and a coil spring (valve element biasing means) 5 for biasing the poppet type valve 2 in the valve closing direction. ing.

  The poppet type valve 2 has an annular plate-like valve portion in which a rubber-based elastic body is fixed by using means such as baking, and is configured to reciprocate in the axial direction integrally with the valve shaft 21. ing. The poppet type valve 2 closes the air passage port 13 by sitting on a valve seat 23 provided on the frame-like wall 22 of the valve housing 3, and opens the air passage port 13 by separating from the valve seat 23. An annular seal rubber 24 for preventing dust from entering the sliding portion of the valve shaft 21 is attached to the outer periphery of the intermediate portion of the valve shaft 21. Further, a plate pressure 25 that functions as a stopper for regulating the maximum lift amount of the poppet type valve 2 is installed on the upper end side of the seal rubber 24 in the figure.

  The valve housing 3 is manufactured by aluminum die casting. The valve housing 3 is integrally formed with a cylindrical side wall portion that accommodates and holds the solenoid actuator 4 therein, and a circular pipe joint 26 that extends from the lower end portion of the side wall portion in the illustrated left direction. ing. The pipe joint 26 is a portion that forms an inlet end (inlet port) of the secondary air flow path 11 formed in the electromagnetic secondary air control valve, and is a discharge port of an air pump (not shown). It has a connection port (air inlet, secondary air inlet) 10 connected via a secondary air pipe (not shown). In addition, the secondary air flow path formed in the valve housing 3 is divided into an upstream secondary air flow path 12 and a downstream secondary air flow path 14 at the lower end of the side wall of the valve housing 3 in the figure. A frame-like wall (partition wall) 22 for partitioning is integrally formed. A central portion of the frame-like wall 22 is an opening, and this opening constitutes an air passage port 13 that forms a valve hole of the electromagnetic valve 1. An annular valve seat 23 on which the poppet type valve 2 is seated is provided at the peripheral portion of the air passage 13 on the lower end side of the frame-like wall 22 in the figure.

  Here, the secondary air flow path formed in the valve housing 3 of the electromagnetic valve 1 of the present embodiment is a secondary air flow path formed upstream of the frame-like wall 22 in the secondary air flow direction. 11 and 12, which communicate with the secondary air flow paths 11 and 12 through an air passage port (valve hole) 13 and are formed downstream of the frame-like wall 22 in the secondary air flow direction. It is comprised by the air flow path 14 grade | etc.,. The secondary air flow path 14 communicates with the secondary air flow paths 16 and 17 formed in the case outlet 9 of the check valve 6 via the air passage port (valve hole) 15 of the check valve 6. ing.

  The solenoid actuator 4 is valve body driving means that is press-fitted and assembled to the inner periphery of the side wall portion of the valve housing 3 of the solenoid valve 1 and drives the poppet type valve 2 in the valve opening direction. The solenoid actuator 4 includes a solenoid coil 28 wound around the coil bobbin 27, a pair of terminals 29 electrically connected to a pair of terminal lead wires of the solenoid coil 28, and a housing that holds these terminals 29. A cover 30, a substantially cylindrical yoke 31 that is press-fitted into the inner periphery of the side wall of the valve housing 3, and a substantially cylindrical stator core 32 that forms a substantially cylindrical coil housing portion between the yoke 31. And a moving core 33 that operates integrally with the poppet type valve 2 and the valve shaft 21 in the axial direction.

  The coil bobbin 27 is made of a resin material (electrically insulating resin) of a thermoplastic resin (for example, polybutylene terephthalate: PBT), and is formed in a substantially cylindrical shape formed between the inner diameter side of the yoke 31 and the outer diameter side of the stator core 32. Is held and fixed in the coil housing portion. The coil bobbin 27 includes a substantially cylindrical tubular portion around which the coil portion of the solenoid coil 28 is wound, and a substantially annular flange-like portion (flange) provided on both ends in the axial direction of the tubular portion. Part) and the like.

  The solenoid coil 28 generates a magnetomotive force when energized to magnetize a plurality of magnetic bodies including the yoke 31, the stator core 32, the moving core 33, and the like, thereby opening the poppet type valve 2 of the electromagnetic valve 1 in the valve opening direction. And the coil bobbin 27 is wound around the outer periphery of the coil bobbin 27 by a plurality of turns. The solenoid coil 28 has a coil part wound around the outer periphery of the coil bobbin 27 and a pair of terminal lead wires taken out from the coil part.

  The pair of terminals 29 are plate-like conductors made of a metal plate. These terminals 29 are covered and protected by the housing cover 30. The pair of terminals 29 has one end inserted into and coupled to a female connector provided on the front end side of the vehicle-side wire harness, and the other end uses welding means for the pair of terminal lead wires of the solenoid coil 28. Are combined. For example, claw-like portions for caulking and fixing the end portions of the pair of terminal lead wires of the solenoid coil 28 are provided at the other end portions of the pair of terminals 29.

  The housing cover 30 is made of a resin material (electrically insulating resin) of a thermoplastic resin (for example, polybutylene terephthalate: PBT), and is a male connector that is mechanically connected to a female connector provided on the distal end side of the vehicle-side wire harness. A mold connector 34 is integrally provided. The male connector 34 includes an electromagnetic valve driving circuit built in the ECU by inserting a female connector provided on the front end side of the vehicle side (ECU side) wire harness into the connector shell of the male connector 34. Electrical connection with the solenoid coil 28 of the solenoid valve 1 is made. The vehicle-side wire harness is a bundle of conductive wires with an insulation protection tube on the outer periphery, and these conductive wires are electrically connected to respective female terminals provided in the female connector.

  A plurality of magnetic bodies composed of the yoke 31, the stator core 32, the moving core 33, and the like form a magnetic circuit together with the solenoid coil 28. Of these magnetic bodies, the yoke 31 and the stator core 32 are fixed iron cores each having a cylindrical portion. The yoke 31 and the coil bobbin 27 are accommodated between the outer diameter side of the stator core 32 and the inner diameter side of the yoke 31. It has a cylindrical coil storage part. Further, an annular ceiling wall is formed on the upper end of the cylindrical portion of the yoke 31 in the figure so as to close the opening side of the cylindrical portion of the yoke 31. The top wall portion is provided with a terminal lead wire extraction hole for extracting a pair of terminal lead wires of the solenoid coil 28.

  An annular flange portion that forms the flow path walls of the secondary air flow paths 11 and 12 is formed at the lower end of the stator core 32 in the figure. Further, a concave portion is formed on the outer diameter side of the cylindrical portion of the stator core 32, and a thin portion 35 for reducing the magnetic path cross-sectional area is provided. The thin portion 35 is provided in order to prevent the magnetic performance from deteriorating due to excessive flow of magnetic flux. As a result, when the yoke 31, the stator core 32, and the moving core 33 are magnetized, the moving core 33 can move linearly in the direction of the central axis of the moving core 33 without being shaken toward the suction portion of the stator core 32. .

  The moving core 33 is a movable iron core formed in a substantially cylindrical shape, and the illustrated upper end portion (small diameter portion) of the valve shaft 21 of the poppet type valve 2 is fitted therein. The moving core 33 has a locking portion that locks a step portion provided between a large diameter portion and a small diameter portion of the valve shaft 21 of the poppet type valve 2. An annular washer 36 is mounted between the illustrated upper end surface of the moving core 33 and the flange portion of the valve shaft 21. The flanged portion of the valve shaft 21 has an outer diameter that is wider than the inner diameter of the through hole of the moving core 33. Therefore, after the moving core 33 is inserted into the sliding hole of the stator core 32 from the upper side in the figure, the valve shaft 21 is inserted into the through hole of the moving core 33 from the lower side in the figure, and the flange portion of the valve shaft 21 is caulked. The moving core 33 is sandwiched between the flange portion and the step portion of the valve shaft 21. Thereby, the poppet type valve 2 and the moving core 33 can operate integrally.

  The coil spring 5 is held on the outer peripheral side of the large diameter portion of the valve shaft 21 and the cylindrical portion (spring inner diameter guide) of the plate pressure 25, and one end portion is locked to the flange portion of the plate pressure 25, and the other end The part is locked to the moving core 33. Here, 37 is an annular seal rubber for preventing leakage of secondary air from the joint between the case outlet 9 of the check valve 6 and the valve housing 3 of the solenoid valve 1. Reference numeral 39 denotes a stay for attaching the valve housing 3 to which the case outlet 9 of the check valve 6 is joined.

  The check valve 6 is a valve that prevents the exhaust gas flowing from the engine exhaust manifold (not shown) to the three-way catalytic converter from flowing back to the air pump or the poppet type valve 2 side of the electromagnetic valve 1 in the engine exhaust pipe. A reed valve 7 that opens and closes a plurality of air passage ports 15 through which secondary air passes, a reed stopper 8 that regulates the degree of opening (maximum opening) of the reed valve 7, and a plurality of air passage ports 15 And a case outlet 9 that holds a metal plate 41 that forms the shape.

  The reed valve 7 is made of a metal material (for example, a leaf spring), and has a double tongue or triple tongue valve portion (free end portion) that opens and closes a plurality of air passage openings 15 on one end side. And having a supported portion (fixed end) supported by the air downstream end surface of the support portion of the metal plate 41 at the other end. Here, the metal plate 41 is made of a metal material such as aluminum, and forms a plurality of air passage openings 15 through which air passes. have. Note that a substantially sun-shaped or substantially eye-shaped rubber-based sealing material is fixed to the passage wall surface of the air passage port 15 by baking or the like.

  The lead stopper 8 is made of a metal plate, and has a double tongue-like or triple tongue-like stopper portion (free end portion) for regulating the opening degree of the reed valve 7 on one end side, and the other end portion. The reed valve 7 has a supported portion (fixed end portion) that is supported by the air downstream end surface of the supported portion. Here, a plurality of through holes pass through the support portion of the metal plate 41, the supported portion of the reed valve 7, and the supported portion of the lead stopper 8. In these through-holes, fastening for fastening and fixing the support portion of the metal plate 41, the supported portion of the reed valve 7 and the supported portion of the reed stopper 8 to the lower end surface of the valve housing 3 of the solenoid valve 1 shown in the drawing. A screw 42 such as a screw is inserted.

  The case outlet 9 is manufactured by aluminum die casting and has secondary air flow paths 16 and 17 therein. The secondary air passages 16 and 17 are portions that communicate with the engine exhaust pipe on the upstream side of the three-way catalytic converter and feed the secondary air of the air pump to the three-way catalytic converter. The case outlet 9 has a jointed portion that is fastened and fixed to a circular joint provided on the opening side of the valve housing 3 of the solenoid valve 1 using a plurality of screws (not shown). ing. Note that an insertion hole 43 (see FIGS. 6, 8, and 9) through which a plurality of screws are inserted is formed in the joined portion of the case outlet 9. The downstream end of the case outlet 9 is a portion that forms an outlet end portion (exit port) of the secondary air flow path 17 formed in the electromagnetic secondary air control valve, and is provided in the engine exhaust pipe. The mounting stay portion (not shown) is fastened and fixed using fixing bolts or screws (not shown).

  Here, in the secondary air flow paths 16 and 17 of the case outlet 9, fine particles such as combustion residues and carbon are discharged from the engine exhaust pipe due to exhaust pulsation generated when the exhaust valve for opening and closing the engine exhaust port is opened and closed. Exhaust gas containing may blow back. Then, exhaust gas flows into the secondary air flow paths 16 and 17 from the connection port 18 with the engine exhaust pipe of the case outlet 9, and particulates contained in the exhaust gas adhere to the reed valve 7 and deposits (deposits) ) May cause a problem that the reed valve 7 is clogged and remains open. Therefore, in the case outlet 9 of the present embodiment, the flow direction of the exhaust gas flowing from the engine exhaust pipe into the secondary air flow paths 16 and 17 through the connection port 18 is set to the electromagnetic valve 1 and the check valve 6. A bent portion 51 that is bent in a direction different from the reed valve 7 side is provided. The front surface (right side surface in the drawing) of the bent portion 51 is opposed to the inflow direction of the exhaust gas flowing into the secondary air flow paths 16 and 17 from the engine exhaust pipe, that is, the connection port (gas inlet, exhaust gas flow). A flow passage wall surface 52 is provided opposite to the inlet 18, the air outlet, and the secondary air outlet 18.

  Further, in the case outlet 9 of the present embodiment, a bag hole-shaped space 19 that opens at the flow channel wall surface 52 of the bent portion 51 is provided on substantially the same central axis as the secondary air flow channel 17 and the connection port 18. Yes. The bag-hole-shaped space 19 functions as a stagnation space (for example, a dead-end bag path-shaped space) in which an exhaust gas flow flowing into the secondary air flow paths 16 and 17 from the engine exhaust pipe is swallowed. The bag hole-shaped space 19 opens so that one end (open end) faces the inflow direction of the exhaust gas, that is, faces the connection port 18, and the other end (back side end) has an airtight plug (interference). Wall) 53. An opening 54 is formed at the opening end of the bag hole-shaped space 19. The opening 54 of the bag hole-shaped space 19 exhausts more than the opening / closing operation range of the poppet type valve 2 of the solenoid valve 1 and the reed stopper 8 of the check valve 6, that is, the opening / closing operation range of the reed valve 7 of the check valve 6. It is provided on the upstream side in the gas inflow direction. The bag hole-shaped space 19 may cause high-temperature exhaust gas to blow back into the secondary air flow paths 16 and 17 of the case outlet 9, thereby reducing the temperature rise around the case outlet 9, particularly the solenoid valve 1. For this purpose, it is provided at a position away from the solenoid valve 1.

  Further, foreign matter such as fine particles contained in the exhaust gas is present on the poppet type valve 2 side of the solenoid valve 1 of the opening 54 of the bag hole-shaped space 19, that is, on the flow path wall surface 52 of the bent portion 51. A foreign matter return portion 55 for preventing the electromagnetic valve 1 from flowing out to the poppet type valve 2 side is provided. The foreign object return portion 55 is provided so as to hang down toward the bottom wall portion 56 of the case outlet 9. Thereby, the opening area of the opening 54 of the bag hole-shaped space 19 is narrower in the bag hole-shaped space 19 than the opening area of the back side (the left side in the drawing) of the bag hole-shaped space 19. Here, on the inner wall surface of the case outlet 9 of the present embodiment on the left side of the figure (the double tongue-shaped valve portion (free end portion side of the reed valve 7 side, the stopper portion (free end portion) side of the reed stopper 8)) The secondary air flow path 17 does not increase the pressure loss of the secondary air flowing into the secondary air flow path 16 from the plurality of air passage openings 15 formed in the metal plate 41 of the check valve 6. A flow path wall surface (curved surface) 57 having a radius of curvature with a certain point as the center is formed so as to flow smoothly.

[Operation of Example 1]
Next, the operation of the secondary air supply device of this embodiment, particularly the electromagnetic secondary air control valve, will be described with reference to FIG. 1 and FIG.

Here, in vehicles such as automobiles, three elements of carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NOx), which are harmful components in exhaust gas discharged from the engine, are collectively included. In addition, a three-way catalytic converter that is converted into harmless components by a chemical reaction is installed. However, the three-way catalyst must maintain the theoretical air-fuel ratio of 15: 1 because the chemical reaction cannot be performed correctly unless the mixing ratio of air and fuel at the time of engine combustion is the stoichiometric air-fuel ratio. In addition, the three-way catalyst does not operate well when the exhaust gas temperature is low (approximately 350 ° C. or less) immediately after the engine is started. For this reason, when the exhaust gas temperature is low when the engine is started, the secondary air generated by operating the air pump is guided to the three-way catalytic converter to activate the three-way catalyst. In particular, the hydrocarbon (HC) is changed into harmless water (H ₂ O) by an oxidizing action.

  Therefore, the ECU applies a pump drive current to the electric motor of the air pump via the pump drive circuit when the exhaust gas temperature is low just after the engine is started. As a result, supply of secondary air by the air pump is started. The ECU also includes a solenoid valve drive circuit, a vehicle-side wire harness, a female connector provided on the distal end side of the vehicle-side wire harness, a male connector 34, and a solenoid coil 28 of the solenoid valve 1 via a pair of terminals 29. A solenoid valve driving current is applied to the. As a result, a plurality of magnetic bodies including the yoke 31, the stator core 32, and the moving core 33 that form a magnetic circuit together with the solenoid coil 28 are magnetized. Then, when the moving core 33 is sucked by the suction portion of the stator core 32, the moving core 33 moves downward in the figure. As the moving core 33 moves downward in the figure, the poppet type valve 2 fixed to the moving core 33 moves downward in the figure against the urging force of the coil spring 5. As a result, the poppet type valve 2 is separated from the valve seat 23 to open the air passage port 13.

Therefore, the secondary air that has flowed into the secondary air flow path 11 of the solenoid valve 1 from the connection port 10 via the secondary air flow path pipe from the discharge port of the air pump is indicated by a white arrow in FIG. As described above, the plurality of air passage openings formed in the metal plate 41 of the check valve 6 through the secondary air passage 12, the air passage opening 13 and the secondary air passage 14 formed in the valve housing 3. 15 flows in. Then, due to the pressure difference between the air pressure in the plurality of air passage openings 15 and the air pressure in the secondary air flow paths 16 and 17, the double tongue-like valve portion of the reed valve 7 bends downward in the figure, and the valve When the portion comes into contact with the stopper portion of the lead stopper 8, the plurality of air passage openings 15 are opened. As a result, the secondary air that has passed through the plurality of air passage openings 15 flows into the secondary air flow path 16 of the case outlet 9 and flows along the curved surface 57 of the case outlet 9. It goes to the flow path 17. The secondary air flows out from the connection port 18 at the downstream end of the secondary air flow path 17 and is sent to the three-way catalytic converter via the engine exhaust pipe on the upstream side of the three-way catalytic converter. For this reason, even when the exhaust gas temperature is low when starting the engine, secondary air generated by operating the air pump is guided to the three-way catalytic converter, so that oxygen (O ₂ ) burns and the three-way catalyst is elevated. ,Activate. In particular, the hydrocarbon (HC) is changed to harmless water (H ₂ O) by the oxidizing action, so that the amount of hydrocarbons discharged into the atmosphere is reduced.

[Features of Example 1]
Here, when the poppet type valve 2 of the solenoid valve 1 is closed, exhaust gas is exhausted from the engine exhaust pipe into the secondary air flow paths 16 and 17 of the case outlet 9 due to exhaust pulsation caused by opening and closing of the exhaust valve of the engine. May flow, and fine particles contained in the exhaust gas may adhere to the reed valve 7 of the check valve 6 to form deposits, and the reed valve 7 may be clogged. When such a trouble occurs, the reed valve 7 is always kept open, and the function of the check valve 6 for preventing the exhaust gas from blowing back from the engine exhaust pipe to the poppet type valve 2 side of the solenoid valve 1 is lowered. Resulting in. As a result, the exhaust gas flows back to the valve housing 3 side of the solenoid valve 1, and a deposit straddles between the annular plate-like valve portion of the poppet type valve 2 and the valve seat 23 of the valve housing 3. May accumulate. In this case, the poppet type valve 2 of the electromagnetic valve 1 sticks (closed and fixed), or a smooth opening / closing operation cannot be performed. When such a trouble occurs, the flow rate of the secondary air pressure-supplied from the air pump to the three-way catalytic converter decreases, and the original function of activating the three-way catalyst is lost.

  In order to avoid the occurrence of such trouble, in the electromagnetic secondary air control valve of this embodiment, the inside of the case outlet 9 of the check valve 6 that connects the valve housing 3 of the solenoid valve 1 and the engine exhaust pipe. In addition, a bag hole-shaped space 19 is provided to allow an exhaust gas flow blown back into the secondary air flow paths 16 and 17 from the engine exhaust pipe, and an opening 54 of the bag hole-shaped space 19 is provided to the secondary air from the engine exhaust pipe. An opening / closing operation range of the poppet-type valve 2 of the solenoid valve 1 and a reed valve of the check valve 6 are opened at the channel wall surface 52 of the bent portion 51 facing the inflow direction of the exhaust gas flowing into the channels 16 and 17. 7 on the upstream side in the exhaust gas inflow direction from the open / close operation range of FIG.

  Thus, when the poppet type valve 2 of the solenoid valve 1 is closed, exhaust gas is exhausted from the engine exhaust pipe into the secondary air flow paths 16 and 17 of the case outlet 9 due to exhaust pulsation caused by opening and closing of the exhaust valve of the engine. As shown by the arrows with black dots in FIG. 2, the exhaust gas blown back from the engine exhaust pipe into the secondary air passages 16, 17 through the connection port 18, When the air travels straight along the bottom wall portion 56 of the case outlet 9, the air flows into the bag-hole-shaped space 19 from the opening 54 and hits the inner surface of the airtight plug 53. As a result, the exhaust gas flow that has flowed into the bag-hole-shaped space 19 stagnates in the bag-hole-shaped space 19 in front of the airtight plug 53, and the exhaust gas flows back into the secondary air flow paths 16, 17 from the engine exhaust pipe. The foreign matter such as fine particles contained in the gas deposits in the bag-hole-like space 19 and it becomes easy to form a deposit. Therefore, the flow rate of the exhaust gas that flows back from the engine exhaust pipe into the secondary air flow paths 16 and 17 toward the reed valve 7 and the reed stopper 8 of the check valve 6 can be reduced. The amount of deposit deposited on the surface of the reed valve 7 of the valve 6 can be reduced.

  Further, in the electromagnetic secondary air control valve of the present embodiment, the opening area of the opening 54 of the bag hole-shaped space 19 is made smaller than the opening area on the back side of the bag hole-shaped space 19. Further, the exhaust gas once flowing into the bag hole-shaped space 19 on the side of the poppet type valve 2 of the electromagnetic valve 1 of the opening 54 of the bag hole-shaped space 19, that is, the flow wall surface 52 of the bent portion 51 is the bag hole-shaped space 19. A foreign matter return portion 55 is provided to make it difficult to flow out from the inside 19 to the poppet type valve 2 side of the electromagnetic valve 1. As a result, when the exhaust gas flows into the bag-hole-shaped space 19 from the opening 54, the exhaust gas swirls in the bag-hole-shaped space 19 due to the presence of the foreign matter return portion 55 as shown by the black dot arrows in FIG. Alternatively, since it recirculates, the flow rate of the exhaust gas that once flows from the engine exhaust pipe into the bag hole-shaped space 19 and then jumps out of the bag hole-shaped space 19 and flows into the poppet type valve 2 side of the solenoid valve 1 can be reduced. . Therefore, deposits are easily accumulated or accumulated in the bag hole-shaped space 19, and deposits are difficult to adhere or accumulate on the surface of the reed valve 7 of the check valve 6.

  As a result, when the reed valve 7 of the check valve 6 is opened, the amount of deposit entering between the reed valve 7 and the metal plate 41 is reduced, so that the reed valve 7 can be prevented from being clogged. Since the clogging of the reed valve 7 can be avoided in this way, the reed valve 7 does not always remain open, and the function of the check valve 6 does not deteriorate. Therefore, the exhaust gas blown back into the secondary air flow paths 16 and 17 from the engine exhaust pipe can be prevented from flowing back to the secondary air flow path 14 side of the valve housing 3 of the electromagnetic valve 1. It becomes difficult for deposits to adhere to or deposit on the surface of the mold valve 2.

  Thereby, even if the poppet type valve 2 of the electromagnetic valve 1 is opened, it is difficult for the deposit to enter between the annular plate-like valve portion of the poppet type valve 2 and the valve seat 23 of the valve housing 3. It is possible to avoid deposits straddling between the annular plate-like valve portion of the poppet type valve 2 and the valve seat 23 of the valve housing 3. As a result, it is possible to avoid the sticking of the poppet type valve 2 of the electromagnetic valve 1 (stick) and the inoperability (or malfunction) of the poppet type valve 2, thereby ensuring a smooth opening / closing operation of the poppet type valve 2. it can. As another effect, the temperature rise in the secondary air flow paths 16 and 17 of the case outlet 9 can be reduced by moving the bag-hole-like space 19 through which the exhaust gas recirculates from the reed valve 7 of the check valve 6, and electromagnetic The temperature rise around the valve 1 can be reduced.

  Further, in the electromagnetic secondary air control valve of the present embodiment, since the curved surface 57 is provided on the inner wall surface of the case outlet 9, the secondary air pressure-fed and supplied from the air pump does not increase the pressure loss. The secondary air flow paths 16 and 17 of the case outlet 9 flow smoothly. At this time, since a negative pressure is generated in the bag hole-shaped space 19 having the opening 54 opened at the flow path wall surface 52 of the bent portion 51 of the case outlet 9, the bag hole is closed when the poppet type valve 2 of the electromagnetic valve 1 is closed. Deposits accumulated or accumulated in the space 19 are sucked back into the engine exhaust pipe. As a result, the deposit does not overflow to the reed valve 7 side even if the inner volume of the bag hole-shaped space 19 is not increased so much, so that the case outlet 9 can be made smaller, that is, the electromagnetic secondary air control valve can be made smaller. Can be achieved. Further, since it is not necessary to newly install a part for discharging the deposit from the bag-hole-shaped space 19, it is possible to reduce the cost by reducing the number of parts and the number of assembling steps.

  FIG. 3 shows the second embodiment of the present invention and is a diagram showing the entire configuration of the electromagnetic secondary air control valve.

  The electromagnetic secondary air control valve of the present embodiment is configured so that the flow direction of the exhaust gas that blows back from the engine exhaust pipe into the secondary air flow paths 16 and 17 to the case outlet 9 of the check valve 6 is changed to the poppet of the solenoid valve 1. A bent portion 51 that is bent in a direction different from the mold valve 2 side is provided. The bent portion 51 is upstream of the opening / closing operation range of the poppet type valve 2 of the solenoid valve 1 and the lead stopper 8 of the check valve 6, that is, the opening / closing operation range of the reed valve 7 of the check valve 6 in the exhaust gas inflow direction. On the side. The front surface (right side surface in the drawing) of the bent portion 51 is opposed to the inflow direction of the exhaust gas flowing into the secondary air flow paths 16 and 17 from the engine exhaust pipe, that is, the flow path wall surface facing the connection port 18. 52 is provided.

  The flow path wall surface 52 of the bent portion 51 is provided in a direction (perpendicular) substantially perpendicular to the axial direction of the bottom wall portion 56 of the case outlet 9 and is connected to the secondary air flow path 16 from the engine exhaust pipe. , 17 also functions as an interference wall that blocks the flow of exhaust gas that flows into the poppet type valve 2 side of the electromagnetic valve 1. Further, an exhaust gas flow flowing from the engine exhaust pipe into the secondary air flow paths 16 and 17 is swallowed in the vicinity of the flow path wall surface 52 of the bent part 51, that is, on the bottom wall part 56 immediately before the flow path wall surface 52. A stagnation space 59 is formed.

  As a result, the exhaust gas flow that has flowed into the secondary air flow paths 16 and 17 from the engine exhaust pipe stagnate in the stagnation space 59 near the flow path wall surface 52 of the bent portion 51, and is upstream of the lead stopper 8 of the check valve 6. Deposits accumulate or accumulate in the stagnation space 59 located on the side. Accordingly, the flow rate of the exhaust gas that flows back from the engine exhaust pipe into the secondary air flow paths 16 and 17 toward the reed valve 7 and the reed stopper 8 of the check valve 6 can be reduced. As a result, foreign matter such as fine particles contained in the exhaust gas blown back into the secondary air flow paths 16 and 17 from the engine exhaust pipe is less likely to adhere to or accumulate on the surface of the reed valve 7 of the check valve 6. It becomes difficult to form a deposit on the valve 7. Therefore, the same effect as in the first embodiment can be realized.

  FIG. 4 shows Embodiment 3 of the present invention, and is a diagram showing the overall configuration of an electromagnetic secondary air control valve.

  In the present embodiment, the flow path wall surface 52 of the bent portion 51 of the case outlet 9 is an inclined surface having an inclination angle that falls toward the connection port 18 with respect to the perpendicular of the axis of the bottom wall portion 56 of the case outlet 9. It also functions as an interference wall that prevents the flow of exhaust gas flowing from the engine exhaust pipe into the secondary air flow paths 16 and 17 toward the poppet type valve 2 side of the solenoid valve 1. In this case, the stagnation space 59 can be a bag-hole-like space as in the first embodiment, and the flow path wall surface 52 of the bent portion 51 is once exhaust gas (into the stagnation space 59). It can also function as a foreign matter return portion for making it difficult for foreign matter such as fine particles contained) to flow out of the stagnation space 59 to the poppet type valve 2 side of the solenoid valve 1.

  FIGS. 5 to 9 show Embodiment 4 of the present invention, FIG. 5 is a diagram showing the overall configuration of an electromagnetic secondary air control valve, and FIG. 6 is a diagram showing a case outlet.

  As shown in FIGS. 5 to 8A, the electromagnetic secondary air control valve of the present embodiment is disposed in the case outlet 9 of the check valve 6 from the engine exhaust pipe to the secondary air flow paths 16 and 17. An interference wall 61 is provided that prevents the flow of exhaust gas that flows into the poppet type valve 2 side of the electromagnetic valve 1. This interference wall 61 is upstream of the opening / closing operation range of the poppet type valve 2 of the solenoid valve 1 and the reed stopper 8 of the check valve 6, that is, the opening / closing operation range of the reed valve 7 of the check valve 6. On the side.

  The interference wall 61 is opposed to the inflow direction of the exhaust gas flowing into the secondary air flow paths 16 and 17 from the engine exhaust pipe, that is, the opposed wall surface 62 facing the connection port 18, and the opposed wall surface 62. A foreign matter return portion 63 protruding from the both sides toward the connection port 18 is provided. The opposing wall surface 62 of the interference wall 61 is provided in a direction (vertical) substantially orthogonal to the axial direction of the bottom wall portion 56 of the case outlet 9. Further, in the vicinity of the opposing wall surface 62 of the interference wall 61, that is, on the bottom wall portion 56 immediately before the opposing wall surface 62, a stagnation space for trapping the exhaust gas flow flowing into the secondary air flow paths 16 and 17 from the engine exhaust pipe. 64 is formed. The stagnation space 64 includes not only the space surrounded by the foreign matter return portion 63 but also the bottom wall portion 56 of the case outlet 9 in the vicinity of the secondary air flow path 17 in the secondary air flow path 16. .

  As a result, when the exhaust gas flow flowing into the secondary air flow paths 16 and 17 from the engine exhaust pipe goes straight, as shown by the black dot arrows in FIGS. It collides with 62 and stagnates (returns or turns) in the stagnation space 64 in the vicinity of the opposing wall surface 62 of the interference wall 61, and deposits accumulate or accumulate in the stagnation space 64. Accordingly, the flow rate of the exhaust gas that flows back from the engine exhaust pipe into the secondary air flow paths 16 and 17 toward the reed valve 7 and the reed stopper 8 of the check valve 6 can be reduced. As a result, foreign matter such as fine particles contained in the exhaust gas blown back into the secondary air flow paths 16 and 17 from the engine exhaust pipe is less likely to adhere to or accumulate on the surface of the reed valve 7 of the check valve 6. It becomes difficult to form a deposit on the valve 7. Therefore, the same effect as in the first embodiment can be realized.

  Here, in the electromagnetic secondary air control valve of the present embodiment, the interference wall 61 is disposed in the secondary air flow path 16 of the case outlet 9 from the bottom wall surface of the bottom wall portion 56 of the case outlet 9 upward in the figure. So that when the poppet type valve 2 of the solenoid valve 1 is opened, the flow of the secondary air flowing into the solenoid valve 1 from the discharge port of the air pump through the secondary air passage pipe is obstructed. There is a possibility of increasing the pressure loss of the secondary air flow. Therefore, in this embodiment, in order to avoid such an increase in the pressure loss of the secondary air flow, as shown in FIGS. 6 and 8A, the flow path wall surfaces 65 on both sides of the interference wall 61 are used. The channel wall surface 66 forming the secondary air channel 16 of the case outlet 9 is provided with an inclination angle capable of rectifying the secondary air.

  Thereby, even when the interference wall 61 is provided so as to protrude into the secondary air flow path 16 of the case outlet 9, the secondary air flow flowing in the secondary air flow path 16 is changed to the flow path wall surface 65 of the interference wall 61. Further, the flow is rectified according to the inclination angle of the flow path wall surface 66 of the case outlet 9. For example, as indicated by white arrows in FIG. 7 and FIG. 8A, the secondary air that has flowed into the secondary air flow path 16 from the plurality of air passage openings 15 flows around both sides of the interference wall 61. It flows into the secondary air flow path 17 of the case outlet 9 via the substantially V-shaped secondary air flow path 67 formed between the road wall surfaces 65 and 66 without increasing the pressure loss.

  In addition, as shown in FIGS. 8B and 9, the electromagnetic secondary air control valve of the present embodiment is connected to the case outlet 9 of the check valve 6 from the engine exhaust pipe to the secondary air flow path 16, A bent portion 71 is provided that bends the flow direction of the exhaust gas blown back into the direction 17 in a direction different from the poppet type valve 2 side of the solenoid valve 1. The bent portion 71 is upstream of the opening / closing operation range of the poppet type valve 2 of the solenoid valve 1 and the lead stopper 8 of the check valve 6, that is, the opening / closing operation range of the reed valve 7 of the check valve 6 in the exhaust gas inflow direction. On the side. Further, on the front surface of the bent portion 71, a flow path wall surface 72 that faces the inflow direction of the exhaust gas that flows into the secondary air flow path 17 from the engine exhaust pipe, that is, faces the connection port 18 is provided.

  And the foreign substance return part 73 which protruded in the connection port 18 side is provided in the both sides of the flow-path wall surface 72 of the bending part 71. As shown in FIG. The flow path wall surface 72 of the bent portion 71 is provided in a direction (perpendicular) substantially perpendicular to the axial direction of the bottom wall portion 56 of the case outlet 9 and is connected to the secondary air flow path 17 from the engine exhaust pipe. It also functions as an interference wall that blocks the flow of exhaust gas flowing into the electromagnetic valve 1 toward the poppet type valve 2 side. Further, in the vicinity of the flow path wall surface 72 of the bent portion 71, that is, on the bottom wall portion 56 immediately before the flow path wall surface 72, a stagnation space for trapping an exhaust gas flow flowing into the secondary air flow path 17 from the engine exhaust pipe. 74 is formed. The stagnation space 74 includes not only the space surrounded by the foreign substance return portion 73 but also the bottom wall portion 56 of the case outlet 9 on the connection port 18 side in the secondary air flow path 17.

  As a result, when the exhaust gas flow flowing into the secondary air flow path 17 from the connection port 18 goes straight, it collides with the flow path wall surface 72 of the bent portion 71 as shown by the black dot arrows in FIG. Thus, the stagnation space 74 near the flow path wall surface 72 of the bent portion 71 stagnates (refluxs or turns), and deposits accumulate or accumulate in the stagnation space 74. Therefore, among the exhaust gas blown back from the engine exhaust pipe into the secondary air flow path 17, the flow rate of the exhaust gas toward the secondary air flow path 16 of the case outlet 9, the reed valve 7 of the check valve 6 and the reed stopper 8. Can be reduced. As a result, foreign matter such as fine particles contained in the exhaust gas blown back into the secondary air flow paths 16 and 17 from the engine exhaust pipe is less likely to adhere to or accumulate on the surface of the reed valve 7 of the check valve 6. It becomes difficult to form a deposit on the valve 7. Therefore, the same effect as in the first embodiment can be realized.

  Further, in this embodiment, in order to avoid an increase in the pressure loss of the secondary air flow, the secondary air can be rectified to the flow wall surface 75 that forms the secondary air flow channel 16 of the case outlet 9. It has a possible inclination angle. Accordingly, even when the bent portion 71 is provided so as to bend the flow of the secondary air flowing in the secondary air flow path 17 of the case outlet 9, the inlet of the secondary air flow path 17 from the secondary air flow path 16 is provided. The secondary air flow toward the section 76 is rectified according to the inclination angle of the flow path wall surface 75 of the case outlet 9. For example, as indicated by white arrows in FIG. 8B, the secondary air that has flowed into the secondary air flow path 16 from the plurality of air passage openings 15 flows along the flow path wall surface 75 to the case outlet 9. It flows into the inlet portion 76 of the secondary air flow path 17 so as to converge.

[Modification]
In this embodiment, the air control valve of the present invention is provided with a stagnation space in which an exhaust gas flow blown back from the engine exhaust pipe is swallowed, that is, a deposit accumulation space for accumulating deposits of fine particles contained in the exhaust gas. Although applied to an electromagnetic secondary air control valve, the air control valve of the present invention is a stagnation space in which unburned gas flow blown back from the combustion chamber of the engine is swallowed, that is, particulates contained in the unburned gas. Intake air flow control valve (intake control valve such as swirl control valve and swirl flow control valve, intake control valve such as tumble control valve and tumble flow control valve) having a deposit accumulation space for accumulating deposits (deposits) or The present invention may be applied to an intake air amount control valve (throttle valve, idle rotation speed control valve). In addition, the air control valve according to the present invention has a stagnation space in which an exhaust gas flow blown back from the engine exhaust pipe, that is, an exhaust gas return provided with a deposit accumulation space for accumulating deposits of fine particles contained in the exhaust gas. You may apply to a flow control valve. In these cases, a check valve is not necessary.

  In this embodiment, the yoke 31, the stator core 32, and the moving core 33 are provided as a plurality of magnetic bodies that form a magnetic circuit together with the solenoid coil 28 of the solenoid valve 1. However, the magnetic circuit together with the solenoid coil 28 of the solenoid valve 1 is provided. As a plurality of magnetic bodies to be formed, the yoke 31 may be eliminated and only the stator core 32 and the moving core 33 may be provided. Further, the stator core 32 may be divided into two or more. In this embodiment, the poppet type valve 2 of the electromagnetic valve 1 is provided as a valve body. However, as the valve body, a poppet type valve driven by a drive motor (motor actuator) or manual operation, a butterfly valve, a rotary valve, etc. A rotary valve may be provided. In this embodiment, the check valve 6 is installed downstream of the poppet type valve (valve element) 2 of the solenoid valve 1 in the secondary air flow direction (upstream in the exhaust gas inflow direction). However, the check valve 6 may not be provided. The case outlet 9 may be integrated with the valve housing 3 to form a housing (tubular body).

It is sectional drawing which showed the whole structure of the electromagnetic type secondary air control valve (Example 1). It is sectional drawing which showed the whole structure of the electromagnetic type secondary air control valve (Example 1). (Example 2) which is sectional drawing which showed the whole structure of the electromagnetic type secondary air control valve. (Example 3) which is sectional drawing which showed the whole structure of the electromagnetic type secondary air control valve. (Example 4) which is sectional drawing which showed the whole structure of the electromagnetic type secondary air control valve. (Example 4) which is the top view which showed the case outlet. (Example 4) which is sectional drawing which showed the whole structure of the electromagnetic type secondary air control valve. (A) is AA sectional drawing of FIG. 7, (b) is the top view which showed the case outlet (Example 4). (Example 4) which is the top view which showed the case outlet. It is sectional drawing which showed the whole structure of the electromagnetic type secondary air control valve (conventional technique).

Explanation of symbols

1 Solenoid valve 2 Solenoid valve poppet type valve (valve)
3 Valve housing of solenoid valve (tubular body, secondary air flow pipe)
4 Solenoid actuator of solenoid valve 5 Coil spring of solenoid valve (valve element biasing means)
6 Check valve 7 Check valve reed valve 8 Check valve reed stopper 9 Check valve case outlet (tubular body, secondary air flow pipe)
11 Secondary air flow path (air flow path) of valve housing
12 Secondary air flow path (air flow path) of valve housing
14 Secondary air flow path (air flow path) of valve housing
15 Metal plate air passage 16 Secondary air flow path (air flow path) of case outlet
17 Case outlet secondary air flow path (air flow path)
18 Case outlet connection (gas inlet)
19 Case outlet bag hole-shaped space
41 Metal plate of check valve 51 Bent part of case outlet 52 Channel wall surface of bent part 53 Airtight plug (interference wall) of case outlet
54 Opening in a bag-hole-shaped space 55 Foreign matter return portion of the case outlet 59 Case stagnation space 61 Case outlet interference wall 62 Interference wall facing wall 63 Interference wall foreign matter return portion 64 Case outlet stagnation space 65 Interference wall Channel wall surface 66 Channel wall surface of case outlet 71 Bent part of case outlet 72 Channel wall surface of bent part 73 Foreign matter return part of bent part 74 Stitch space of case outlet 75 Channel wall surface of case outlet

Claims (14)

A tubular body forming an air flow path communicating with a combustion chamber or an exhaust pipe of an internal combustion engine;
In the air control valve provided with a valve body that can be freely opened and closed in the tubular body,
The tubular body has a bent portion that bends the flow direction of gas flowing into the air flow path from a combustion chamber or an exhaust pipe of the internal combustion engine in a direction different from the valve body side,
The air control valve according to claim 1, wherein the bent portion is provided on an upstream side in a gas inflow direction from an opening / closing operation range of the valve body. The air control valve according to claim 1,
The bent portion has a channel wall surface facing the inflow direction of gas flowing into the air channel from a combustion chamber or an exhaust pipe of the internal combustion engine,
An air control valve characterized in that a stagnation space is provided in the vicinity of the flow path wall surface of the bent portion to allow a gas flow flowing into the air flow path from a combustion chamber or an exhaust pipe of the internal combustion engine. A tubular body forming an air flow path communicating with a combustion chamber or an exhaust pipe of an internal combustion engine;
In the air control valve provided with a valve body that can be freely opened and closed in the tubular body,
The tubular body has a stagnation space in which a gas flow flowing into the air flow path from a combustion chamber or an exhaust pipe of the internal combustion engine is contained,
The stagnation space has an opening at one end so as to face the inflow direction of gas flowing into the air flow path from the combustion chamber or exhaust pipe of the internal combustion engine,
The air control valve is characterized in that the opening of the stagnation space is provided on the upstream side in the gas inflow direction from the opening / closing operation range of the valve body. The air control valve according to claim 3,
The tubular body has a bent portion that bends the flow direction of gas flowing into the air flow path from a combustion chamber or an exhaust pipe of the internal combustion engine in a direction different from the valve body side,
The bent portion has a channel wall surface facing the inflow direction of gas flowing into the air channel from a combustion chamber or an exhaust pipe of the internal combustion engine,
The air control valve characterized in that the opening of the stagnation space is opened at the flow path wall surface of the bent portion. In the air control valve according to claim 3 or 4,
The air control valve according to claim 1, wherein an opening area of the stagnation space has a smaller opening area than a back side of the stagnation space. In the air control valve according to any one of claims 3 to 5,
An air control valve, wherein an opening of the stagnation space is provided with a foreign matter return portion for making it difficult for the gas once flowing into the stagnation space to flow out of the stagnation space to the valve body side. The air control valve according to claim 6.
The air control valve, wherein the foreign matter return portion is provided on the valve body side of the opening of the stagnation space. A tubular body forming an air flow path communicating with a combustion chamber or an exhaust pipe of an internal combustion engine;
In the air control valve provided with a valve body that can be freely opened and closed in the tubular body,
The tubular body has an interference wall that prevents the flow of gas from the combustion chamber or exhaust pipe of the internal combustion engine into the air flow path and toward the valve body,
The air control valve according to claim 1, wherein the interference wall is provided on an upstream side in a gas inflow direction from an opening / closing operation range of the valve body. The air control valve according to claim 8,
The interference wall has a wall surface facing the inflow direction of gas flowing into the air flow path from a combustion chamber or an exhaust pipe of the internal combustion engine,
An air control valve characterized in that a stagnation space is provided in the vicinity of the wall surface of the interference wall to allow a gas flow flowing into the air flow path from a combustion chamber or an exhaust pipe of the internal combustion engine. The air control valve according to claim 9,
The tubular body is an air passage pipe connected to an exhaust pipe through which exhaust gas flowing out from a combustion chamber of the internal combustion engine flows,
The air flow path is a secondary air flow path for introducing secondary air pressure-fed and supplied from an air pump into an exhaust system of the internal combustion engine,
From the air pump, the secondary air flow path is formed on a flow path wall surface forming the secondary air flow path of the interference wall or a flow path wall surface of the air flow path tube forming the secondary air flow path. An air control valve having an inclination angle capable of rectifying the flow of secondary air that flows into the exhaust pipe and flows toward the exhaust pipe. In the air control valve according to any one of claims 1 to 10,
The tubular body is an air passage pipe connected to an exhaust pipe through which exhaust gas flowing out from a combustion chamber of the internal combustion engine flows,
The air flow path is a secondary air flow path for introducing secondary air pressure-fed and supplied from an air pump into an exhaust system of the internal combustion engine,
The said valve body is a valve which opens and closes the said secondary air flow path, The air control valve characterized by the above-mentioned. The air control valve according to claim 11,
The tubular body has a case outlet containing a check valve for preventing exhaust gas flowing in the exhaust pipe from flowing back to the valve side, closer to the exhaust pipe side than the opening / closing operation range of the valve,
The air control valve according to claim 1, wherein a stagnation space is provided in the case outlet to allow an exhaust gas flow flowing from the exhaust pipe of the internal combustion engine into the air flow path. The air control valve according to claim 12,
The check valve has a metal plate that forms an air passage through which secondary air passes, a reed valve that opens and closes the air passage, and a reed stopper that regulates the degree of opening of the reed valve,
The stagnation space is provided upstream of the lead stopper in the exhaust gas inflow direction with respect to the lead stopper. In the air control valve according to any one of claims 1 to 9,
The tubular body is an air passage pipe connected to an exhaust pipe through which exhaust gas flowing out from a combustion chamber of the internal combustion engine flows,
The air flow path is an exhaust gas recirculation path for introducing a part of the exhaust gas flowing out from the combustion chamber of the internal combustion engine into the intake pipe of the internal combustion engine,
The air control valve, wherein the valve body is a valve for adjusting an exhaust gas recirculation amount flowing in the exhaust gas recirculation path.

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