JP2018003633A

JP2018003633A - Passage selector valve for exhaust gas recirculation device

Info

Publication number: JP2018003633A
Application number: JP2016128159A
Authority: JP
Inventors: 河井　伸二; Shinji Kawai; 伸二河井; 吉岡　衛; Mamoru Yoshioka; 衛吉岡
Original assignee: Aisan Industry Co Ltd
Current assignee: Aisan Industry Co Ltd
Priority date: 2016-06-28
Filing date: 2016-06-28
Publication date: 2018-01-11

Abstract

PROBLEM TO BE SOLVED: To change-over flow passages when functions are changed over between LPL and HPL without communicating a first downstream side EGR passage with a second downstream side EGR passage.SOLUTION: A three-way valve 27 is provided with an upstream side passage part 42 for use in feeding EGR gas; a first downstream side passage part 43 for feeding out EGR gas to the first downstream side EGR passage; and a second downstream side passage part 44 for use in feeding out EGR gas to the second downstream side EGR passage. The first downstream side passage part 43 is provided with a first valve body 45 that is oscillated around a first rotating shaft 46 and can be sat on a first valve seat 43a at the valve seat 43a, the second downstream side passage part 44 is provided with a second valve body 47 that is oscillated around a second rotating shaft 48 and can be sat on a second valve seat 44a at a downstream side of the valve seat 44a. There is provided a cooperative driving mechanism 50 constituted to include an operating state in which the first valve body 45 and the second valve body 47 are cooperated to each other and the second valve body 47 is closed when the first valve body 45 is opened and another operating state in which the first valve body 45 is closed when the second valve body 47 is opened.SELECTED DRAWING: Figure 11

Description

この発明は、エンジンから排出される排気の一部を排気還流ガスとして吸気通路へ流してエンジンへ還流させる排気還流装置であって、いわゆる高圧ループタイプと低圧ループタイプの両方を備え、両タイプを必要に応じて切り替えて使用するように構成した排気還流装置に係り、詳しくは、排気還流ガスの流路を切り替えるために使用される流路切替弁に関する。 The present invention is an exhaust gas recirculation device for flowing a part of exhaust discharged from an engine as an exhaust gas recirculation gas into an intake passage and recirculating it to the engine. The exhaust gas recirculation apparatus includes both a so-called high pressure loop type and a low pressure loop type. The present invention relates to an exhaust gas recirculation device configured to be switched and used as necessary, and more particularly to a flow path switching valve used for switching an exhaust gas recirculation gas flow path.

従来、この種の技術として、例えば、下記の特許文献１に記載される内燃機関の制御装置が知られている。この装置は、過給機を備えたエンジンに設けられ、高圧ループタイプの排気還流装置（以下「ＥＧＲ装置」という。）と、低圧ループタイプのＥＧＲ装置を備える。高圧ループタイプのＥＧＲ装置は、タービンより上流の排気通路とコンプレッサより下流の吸気通路とを接続するＥＧＲ通路にＥＧＲ弁が設けられている。また、低圧ループタイプのＥＧＲ装置は、タービンより下流の排気通路とコンプレッサより上流の吸気通路とを接続するＥＧＲ通路にＥＧＲ弁が設けられている。 Conventionally, as this type of technology, for example, a control device for an internal combustion engine described in Patent Document 1 below is known. This device is provided in an engine equipped with a supercharger, and includes a high-pressure loop type exhaust gas recirculation device (hereinafter referred to as “EGR device”) and a low-pressure loop type EGR device. In the high-pressure loop type EGR device, an EGR valve is provided in an EGR passage that connects an exhaust passage upstream of the turbine and an intake passage downstream of the compressor. The low pressure loop type EGR device is provided with an EGR valve in an EGR passage that connects an exhaust passage downstream of the turbine and an intake passage upstream of the compressor.

一般に、高圧ループタイプと低圧ループタイプとを併用するシステムでは、非過給時である低回転低負荷域において、高圧ループタイプにより応答性のよい高圧ＥＧＲを実施することができる。一方、過給時である中回転中負荷域ないし高回転高負荷域において、低圧ループタイプによりＥＧＲガスを吸気へ良好に混入できる低圧ＥＧＲを実施することができる。これは、低圧ループタイプでは、ＥＧＲ通路から吸気通路へ流れるＥＧＲガスが、コンプレッサ、スロットル弁及び吸気マニホルドを経由する長い経路でエンジンに還流されるからである。 In general, in a system using both a high-pressure loop type and a low-pressure loop type, high-pressure EGR with better responsiveness can be implemented by a high-pressure loop type in a low-rotation low-load region that is not supercharged. On the other hand, low-pressure EGR that allows EGR gas to be well mixed into the intake air can be implemented by the low-pressure loop type in a middle-rotation middle load range or high-rotation high-load range that is during supercharging. This is because, in the low pressure loop type, EGR gas flowing from the EGR passage to the intake passage is returned to the engine through a long route passing through the compressor, the throttle valve, and the intake manifold.

ところが、特許文献１に記載の制御装置では、高圧ループタイプと低圧ループタイプのそれぞれにＥＧＲ弁を設けなければならず、構成が複雑になるばかりでなく、装置全体がコスト高になる傾向があった。また、ＥＧＲの大流量化要請に応えるためには、二つのＥＧＲ弁の双方を大流量化に対応できる電動弁にする必要があり、この点でも装置全体がコスト高になる傾向があった。 However, in the control device described in Patent Document 1, an EGR valve must be provided for each of the high-pressure loop type and the low-pressure loop type, which not only complicates the configuration but also tends to increase the cost of the entire device. It was. Further, in order to meet the demand for a large flow rate of EGR, both of the two EGR valves need to be motorized valves that can cope with the large flow rate, and in this respect as well, the entire apparatus tends to be expensive.

特開２０１２−１６３００９号公報JP2012-163209A

ここで、ＥＧＲにつき、高圧ループタイプの機能と低圧ループタイプの機能を選択的に実施でき、しかも、その実施を比較的低コストで実現できることが望まれる。そのために、ＥＧＲ装置を次のような構成にすることが考えられる。すなわち、ＥＧＲ通路に設けられるＥＧＲ弁を一つとし、ＥＧＲ弁より下流のＥＧＲ通路を第１下流側ＥＧＲ通路と第２下流側ＥＧＲ通路に分岐させる。また、第１下流側ＥＧＲ通路の出口をスロットル弁より下流の吸気通路に接続し、第２下流側ＥＧＲ通路の出口をスロットル弁より上流の吸気通路に接続する。また、ＥＧＲ通路の分岐部分に、ＥＧＲ通路を流れるＥＧＲガスを第１下流側ＥＧＲ通路と第２下流側ＥＧＲ通路へ選択的に流すために流路を切り替えるための流路切替弁を設ける。そして、この流路切替弁を切り替えることにより、高圧ループタイプの機能と低圧ループタイプの機能を切り替えるように構成する。 Here, for the EGR, it is desired that a high-pressure loop type function and a low-pressure loop type function can be selectively implemented, and that the implementation can be realized at a relatively low cost. For this purpose, it is conceivable to configure the EGR device as follows. That is, one EGR valve is provided in the EGR passage, and the EGR passage downstream from the EGR valve is branched into the first downstream EGR passage and the second downstream EGR passage. The outlet of the first downstream EGR passage is connected to the intake passage downstream of the throttle valve, and the outlet of the second downstream EGR passage is connected to the intake passage upstream of the throttle valve. In addition, a flow path switching valve for switching the flow path is provided at a branch portion of the EGR path to selectively flow EGR gas flowing through the EGR path to the first downstream EGR path and the second downstream EGR path. Then, the high-pressure loop type function and the low-pressure loop type function are switched by switching the flow path switching valve.

ところが、上記した流路切替弁では、流路を切り替えるときに、第１下流側ＥＧＲ通路と第２下流側ＥＧＲ通路のうち一方への流路が閉じられる前に他方への流路が開かれることがある。このため、第１下流側ＥＧＲ通路と第２下流側ＥＧＲ通路が互いに連通するおそれがある。例えば、低圧ループタイプの機能から高圧ループタイプの機能へ切り替えるときは、第１下流側ＥＧＲ通路を介して新気がエンジン（燃焼室）に流入し、エンジンの出力が変動するおそれがある。一方、高圧ループタイプの機能から低圧ループタイプの機能へ切り替えるときは、第２下流側ＥＧＲ通路及び吸気通路を介してエンジン（燃焼室）へ過剰にＥＧＲガスが導入され、エミッションが悪化するおそれがある。また、高圧ループタイプの機能のときに、過給により吸気圧が上昇すると、第１下流側ＥＧＲ通路から上流側ＥＧＲ通路を介して排気通路に新気が流入するおそれがある。 However, in the above-described flow path switching valve, when switching the flow path, the flow path to the other is opened before the flow path to one of the first downstream EGR passage and the second downstream EGR passage is closed. Sometimes. For this reason, there is a possibility that the first downstream EGR passage and the second downstream EGR passage communicate with each other. For example, when switching from a low pressure loop type function to a high pressure loop type function, fresh air may flow into the engine (combustion chamber) via the first downstream EGR passage, and the engine output may fluctuate. On the other hand, when switching from the high pressure loop type function to the low pressure loop type function, the EGR gas may be excessively introduced into the engine (combustion chamber) via the second downstream EGR passage and the intake passage, and the emission may be deteriorated. is there. Further, when the intake pressure rises due to supercharging during the high pressure loop type function, fresh air may flow from the first downstream EGR passage into the exhaust passage through the upstream EGR passage.

この発明は、上記事情に鑑みてなされたものであって、その目的は、低圧ループタイプと高圧ループタイプとの間でそれらの機能を切り替えるときに、第１下流側排気還流通路と第２下流側排気還流通路とを互いに連通させることなく流路を切り替えることを可能とした排気還流装置の流路切替弁を提供することにある。 The present invention has been made in view of the above circumstances, and an object thereof is to switch the first downstream exhaust recirculation passage and the second downstream when switching their functions between the low pressure loop type and the high pressure loop type. An object of the present invention is to provide a flow path switching valve of an exhaust gas recirculation apparatus that can switch the flow path without communicating with the side exhaust gas recirculation passage.

上記目的を達成するために、請求項１に記載の発明は、エンジンに吸気を導入するための吸気通路と、吸気通路に設けられ、吸気通路における吸気量を調節するための吸気量調節弁と、エンジンから排気通路へ導出される排気の一部を排気還流ガスとして吸気通路へ流してエンジンへ還流させるための排気還流通路と、排気還流通路に設けられ、排気還流ガスの流量を調節するための排気還流弁と、排気還流弁より下流の排気還流通路が第１下流側排気還流通路と第２下流側排気還流通路に分岐されることと、第１下流側排気還流通路が吸気量調節弁より下流の吸気通路に接続されると共に、第２下流側排気還流通路が吸気量調節弁より上流の吸気通路に接続されることとを備えた排気還流装置において、排気還流通路の分岐部分に設けられ、排気還流通路を流れる排気還流ガスを第１下流側排気還流通路と第２下流側排気還流通路へ選択的に流すために流路を切り替えるように構成された流路切替弁であって、ハウジングと、ハウジングに設けられ、排気還流弁から流れる排気還流ガスを導入するための上流側通路部と、ハウジングに設けられ、第１下流側排気還流通路へ排気還流ガスを導出するための第１下流側通路部と、ハウジングに設けられ、第２下流側排気還流通路へ排気還流ガスを導出するための第２下流側通路部と、第１下流側通路部に設けられる第１弁座と、第１下流側通路部を開閉するために、第１回転軸を中心に揺動可能に設けられると共に、第１弁座の下流側にて第１弁座に着座可能に設けられた板状をなす第１弁体と、第２下流側通路部に設けられる第２弁座と、第２下流側通路部を開閉するために、第２回転軸を中心に揺動可能に設けられると共に、第２弁座の下流側にて第２弁座に着座可能に設けられた板状をなす第２弁体と、第１弁体と第２弁体を連動して開弁及び閉弁させると共に、第１弁体が開弁するときに第２弁体が第２弁座に着座して閉弁する第１の動作状態と、第２弁体が開弁するときに第１弁体が第１弁座に着座して閉弁する第２の動作状態とを含み、第１の動作状態と第２の動作状態とを切り替えるように構成された連動駆動機構とを備えたことを趣旨とする。 In order to achieve the above object, an invention according to claim 1 is an intake passage for introducing intake air into an engine, and an intake air amount adjusting valve provided in the intake passage for adjusting an intake air amount in the intake passage. In order to adjust the flow rate of the exhaust gas recirculation gas provided in the exhaust gas recirculation passage and the exhaust gas recirculation passage for flowing a part of the exhaust gas led out from the engine to the exhaust gas passage as the exhaust gas recirculation gas to the intake passage and recirculating to the engine The exhaust gas recirculation valve, the exhaust gas recirculation passage downstream from the exhaust gas recirculation valve are branched into a first downstream exhaust recirculation passage and a second downstream exhaust recirculation passage, and the first downstream exhaust recirculation passage is an intake air amount adjustment valve In the exhaust gas recirculation apparatus, the exhaust gas recirculation device is provided at a branch portion of the exhaust gas recirculation passage. The exhaust gas recirculation device includes a second downstream exhaust gas recirculation passage connected to an intake air passage upstream of the intake air amount adjustment valve. Is A flow path switching valve configured to switch a flow path so as to selectively flow exhaust gas recirculation gas flowing through an exhaust gas recirculation path to a first downstream exhaust recirculation path and a second downstream exhaust recirculation path, An upstream passage portion provided in the housing for introducing the exhaust gas recirculation gas flowing from the exhaust gas recirculation valve, and a first downstream side provided in the housing for deriving the exhaust gas recirculation gas to the first downstream exhaust recirculation passage A passage portion, a second downstream passage portion provided in the housing for leading exhaust recirculation gas to the second downstream exhaust recirculation passage; a first valve seat provided in the first downstream passage portion; In order to open and close the downstream side passage portion, a plate-like first plate is provided that can swing about the first rotation shaft and that can be seated on the first valve seat on the downstream side of the first valve seat. 1 valve body and a second provided in the second downstream passage portion In order to open and close the seat and the second downstream passage portion, it is provided so as to be swingable about the second rotation shaft, and is provided so as to be seated on the second valve seat on the downstream side of the second valve seat. The plate-shaped second valve body, the first valve body and the second valve body are opened and closed in conjunction with each other, and when the first valve body is opened, the second valve body is moved to the second valve seat. A first operation state in which the first valve body is seated on the first valve seat and the valve is closed when the second valve body is opened, It is intended to include an interlocking drive mechanism configured to switch between the first operation state and the second operation state.

上記発明の構成によれば、連動駆動機構が、第１弁体と第２弁体を連動して開弁及び閉弁させると共に、第１弁体が開弁するときに第２弁体が第２弁座に着座して閉弁する第１の動作状態と、第２弁体が開弁するときに第１弁体が第１弁座に着座して閉弁する第２の動作状態とを含み、第１の動作状態と第２の動作状態とを切り替えるように構成される。従って、第１弁体と第２弁体のうち一方が開弁するときは他方が閉弁するので、その開弁及び閉弁の切り替え時に、第１弁座より下流の第１下流側通路部と第２弁座より下流の第２下流側通路部とが互いに連通することがない。また、流路切替弁の第１下流側通路部では、板状をなす第１弁体が第１回転軸を中心に揺動可能に設けられると共に、第１弁座の下流側にて第１弁座に着座可能に設けられる。同様に、第２下流側通路部では、板状をなす第２弁体が第２回転軸を中心に揺動可能に設けられると共に、第２弁座の下流側にて第２弁座に着座可能に設けられる。従って、第１弁体が閉弁したときは、第１弁座を境にした第１下流側通路部の上流側と下流側との間の圧力差により、第１弁体が第１弁座に押し付けられる。同様に、第２弁体が閉弁したときは、第２弁座を境にした第２下流側通路部の上流側と下流側との間の圧力差により、第２弁体が第２弁座に押し付けられる。 According to the configuration of the above invention, the interlocking drive mechanism interlocks the first valve body and the second valve body to open and close, and the second valve body is the first when the first valve body opens. A first operation state in which the two valve seats are seated and closed; and a second operation state in which the first valve body is seated on the first valve seat and the valve is closed when the second valve body is opened. And is configured to switch between a first operating state and a second operating state. Therefore, when one of the first valve body and the second valve body is opened, the other valve is closed. Therefore, when the valve is opened and closed, the first downstream passage section downstream from the first valve seat is used. And the second downstream passage portion downstream from the second valve seat do not communicate with each other. Further, in the first downstream passage portion of the flow path switching valve, a plate-shaped first valve body is provided so as to be able to swing around the first rotation shaft, and at the downstream side of the first valve seat. It is provided so as to be seated on the valve seat. Similarly, in the second downstream passage portion, a plate-like second valve body is provided so as to be swingable about the second rotation shaft, and is seated on the second valve seat downstream of the second valve seat. Provided possible. Therefore, when the first valve body is closed, the first valve body is moved to the first valve seat due to the pressure difference between the upstream side and the downstream side of the first downstream passage portion with the first valve seat as a boundary. Pressed against. Similarly, when the second valve body is closed, the second valve body is moved to the second valve due to a pressure difference between the upstream side and the downstream side of the second downstream passage portion with the second valve seat as a boundary. Pressed against the seat.

上記目的を達成するために、請求項２に記載の発明は、請求項１に記載の発明において、連動駆動機構は、第１の動作状態と第２の動作状態との間に、第１弁体と第２弁体の双方を閉弁する第３の動作状態を含むように構成されたことを趣旨とする。 In order to achieve the above object, the invention according to claim 2 is the invention according to claim 1, wherein the interlocking drive mechanism includes a first valve between the first operation state and the second operation state. It is intended to include a third operation state in which both the body and the second valve body are closed.

上記発明の構成によれば、請求項１に記載の発明の作用に加え、連動駆動機構につき、第１の動作状態と第２の動作状態との間に第３の動作状態が設けられるので、第１弁体と第２弁体の開弁及び閉弁の切り替え時に、第１弁体と第２弁体の双方が一旦閉弁する。従って、開弁及び閉弁の切り替え時に、第１弁座より下流の第１下流側通路部と第２弁座より下流の第２下流側通路部との連通が確実に遮断される。 According to the configuration of the invention, in addition to the operation of the invention according to claim 1, the interlocking drive mechanism is provided with the third operation state between the first operation state and the second operation state. At the time of switching between opening and closing of the first valve body and the second valve body, both the first valve body and the second valve body are once closed. Therefore, at the time of switching between valve opening and valve closing, the communication between the first downstream passage portion downstream from the first valve seat and the second downstream passage portion downstream from the second valve seat is reliably blocked.

上記目的を達成するために、請求項３に記載の発明は、請求項１又は２に記載の発明において、第１下流側通路部において、第１回転軸は、排気還流ガスの流れからずれた位置に配置され、第２下流側通路部において、第２回転軸は、排気還流ガスの流れからずれた位置に配置されたことを趣旨とする。 In order to achieve the above object, according to a third aspect of the present invention, in the first or second aspect of the present invention, the first rotating shaft is deviated from the flow of the exhaust gas recirculation gas in the first downstream passage portion. The second rotating shaft is arranged at a position shifted from the flow of the exhaust gas recirculation gas in the second downstream passage portion.

上記発明の構成によれば、請求項１又は２に記載の発明の作用に加え、第１下流側通路部において、第１回転軸が排気還流ガスの流れからずれた位置に配置され、第２下流側通路部において、第２回転軸が、排気還流ガスの流れからずれた位置に配置されるので、第１回転軸と第２回転軸が排気還流ガスに曝され難くなる。 According to the configuration of the above invention, in addition to the operation of the invention described in claim 1 or 2, in the first downstream passage portion, the first rotating shaft is disposed at a position deviated from the flow of the exhaust gas recirculation gas. In the downstream passage portion, the second rotation shaft is disposed at a position deviated from the flow of the exhaust gas recirculation gas, so that the first rotation shaft and the second rotation shaft are not easily exposed to the exhaust gas recirculation gas.

上記目的を達成するために、請求項４に記載の発明は、請求項１乃至３のいずれかに記載の発明において、第１弁体を閉弁方向へ付勢するための第１の付勢手段と、第２弁体を閉弁方向へ付勢するための第２の付勢手段とを更に備えたことを趣旨とする。 In order to achieve the above object, the invention according to claim 4 is the first urging force for urging the first valve body in the valve closing direction in the invention according to any one of claims 1 to 3. The present invention further includes means and second urging means for urging the second valve body in the valve closing direction.

上記発明の構成によれば、請求項１乃至３のいずれかに記載の発明の作用に加え、第１弁体が第１の付勢手段により閉弁方向へ付勢され、第２弁体が第２の付勢手段により閉弁方向へ付勢される。従って、閉弁時には、各付勢手段の付勢力により、各弁体が対応する弁座に押さえ付けられる。 According to the configuration of the invention, in addition to the operation of the invention according to any one of claims 1 to 3, the first valve body is urged in the valve closing direction by the first urging means, and the second valve body is It is urged in the valve closing direction by the second urging means. Therefore, when the valve is closed, each valve element is pressed against the corresponding valve seat by the urging force of each urging means.

請求項１に記載の発明によれば、低圧ループタイプと高圧ループタイプとの間で機能を切り替えるときに、第１下流側排気還流通路と第２下流側排気還流通路とを互いに連通させることなく流路を切り替えることができる。また、第１弁体又は第２弁体の閉弁時に、各弁体と対応する各弁座との間のシール性を向上させることができる。 According to the first aspect of the invention, when the function is switched between the low pressure loop type and the high pressure loop type, the first downstream exhaust recirculation passage and the second downstream exhaust recirculation passage are not communicated with each other. The flow path can be switched. Moreover, the sealing performance between each valve body and each corresponding valve seat can be improved when the first valve body or the second valve body is closed.

請求項２に記載の発明によれば、請求項１に記載の発明の効果に加え、低圧ループタイプと高圧ループタイプとの間で機能を切り替えるときに、第１下流側排気還流通路と第２下流側排気還流通路との連通を確実に防止することができる。 According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, when the function is switched between the low pressure loop type and the high pressure loop type, the first downstream exhaust recirculation passage and the second Communication with the downstream exhaust gas recirculation passage can be reliably prevented.

請求項３に記載の発明によれば、請求項１又は２に記載の発明の効果に加え、第１回転軸及び第２回転軸に対する凝縮水やデポジットの付着を防止することができ、それら回転軸の腐食や固着を防止することができる。 According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, it is possible to prevent the condensed water and deposits from adhering to the first rotating shaft and the second rotating shaft. Corrosion and sticking of the shaft can be prevented.

請求項４に記載の発明によれば、請求項１乃至３のいずれかに記載の発明の効果に加え、第１弁体又は第２弁体が閉弁したときに、各弁体と対応する各弁座との間のシール性を向上させることができる。 According to the invention of claim 4, in addition to the effect of the invention of any of claims 1 to 3, when the first valve body or the second valve body is closed, it corresponds to each valve body. The sealing performance between the valve seats can be improved.

一実施形態に係り、ガソリンエンジンシステムを示す概略構成図。1 is a schematic configuration diagram showing a gasoline engine system according to an embodiment. 一実施形態に係り、三方弁を示す斜視図。The perspective view which concerns on one Embodiment and shows a three-way valve. 一実施形態に係り、三方弁を示す正面図。The front view which concerns on one Embodiment and shows a three-way valve. 一実施形態に係り、三方弁を示す背面図。The rear view which concerns on one Embodiment and shows a three-way valve. 一実施形態に係り、三方弁を示す平面図。The top view which concerns on one Embodiment and shows a three-way valve. 一実施形態に係り、三方弁を示す底面図。The bottom view showing a three-way valve concerning one embodiment. 一実施形態に係り、三方弁を示す右側面図。The right view which concerns on one Embodiment and shows a three-way valve. 一実施形態に係り、三方弁を示す左側面図。The left view which concerns on one Embodiment and shows a three-way valve. 一実施形態に係り、三方弁の一動作を示す図８のＡ−Ａ線断面図。FIG. 9 is a cross-sectional view taken along line AA of FIG. 8 illustrating one operation of the three-way valve according to the embodiment. 一実施形態に係り、三方弁の別の動作を示す図８のＡ−Ａ線断面図。FIG. 9 is a cross-sectional view taken along line AA of FIG. 8 illustrating another operation of the three-way valve according to the embodiment. 一実施形態に係り、連動駆動機構の第１動作状態と各弁体の動作状態をハウジングの一部を破断して示す概略図。Schematic which shows the 1st operation state of an interlocking drive mechanism, and the operation state of each valve body which fractures a part of housing, concerning one embodiment. 一実施形態に係り、連動駆動機構の第３動作状態と各弁体の動作状態をハウジングの一部を破断して示す概略図。The schematic diagram which concerns on one Embodiment and shows the 3rd operation state of an interlocking drive mechanism, and the operation state of each valve body by fracture | rupturing a part of housing. 一実施形態に係り、連動駆動機構の第２動作状態と各弁体の動作状態をハウジングの一部を破断して示す概略図。The schematic diagram which concerns on one Embodiment and shows the 2nd operation state of an interlocking drive mechanism, and the operation state of each valve body by fracture | rupturing a part of housing.

以下、この発明における排気還流装置の流路切替弁をガソリンエンジンシステムに具体化した一実施形態につき図面を参照して詳細に説明する。 Hereinafter, an embodiment in which a flow path switching valve of an exhaust gas recirculation apparatus in the present invention is embodied in a gasoline engine system will be described in detail with reference to the drawings.

図１に、この実施形態におけるガソリンエンジンシステムを概略構成図により示す。自動車に搭載されたガソリンエンジンシステムは、レシプロタイプのエンジン１を備える。エンジン１には、その各気筒へ吸気を導入するための吸気通路２と、各気筒から排気を導出するための排気通路３が設けられる。吸気通路２と排気通路３には、過給機５が設けられる。吸気通路２には、エアクリーナ４、過給機５のコンプレッサ５ａ、インタークーラ６、スロットル装置７及び吸気マニホルド８が設けられる。スロットル装置７は、バタフライ式のスロットル弁７ａを開閉させることにより、吸気通路２における吸気量を調節するようになっている。この実施形態で、スロットル装置７は、本発明の吸気量調節弁の一例に相当する。吸気マニホルド８は、サージタンク８ａと、サージタンク８ａから各気筒へ分岐する複数の分岐通路８ｂとを含む。排気通路３には、過給機５のタービン５ｂと、排気を浄化する触媒１０が設けられる。エンジン１は周知の構成を備え、燃料と吸気との混合気を燃焼し、燃焼後の排気を排気通路３へ排出するようになっている。過給機５は、タービン５ｂが排気の流れにより回転動作し、それに連動してコンプレッサ５ａが回転することにより、吸気通路２における吸気を昇圧させるようになっている。 FIG. 1 shows a schematic configuration diagram of a gasoline engine system in this embodiment. A gasoline engine system mounted on an automobile includes a reciprocating engine 1. The engine 1 is provided with an intake passage 2 for introducing intake air into each cylinder and an exhaust passage 3 for deriving exhaust gas from each cylinder. A supercharger 5 is provided in the intake passage 2 and the exhaust passage 3. The intake passage 2 is provided with an air cleaner 4, a compressor 5 a of the supercharger 5, an intercooler 6, a throttle device 7, and an intake manifold 8. The throttle device 7 adjusts the amount of intake air in the intake passage 2 by opening and closing a butterfly throttle valve 7a. In this embodiment, the throttle device 7 corresponds to an example of an intake air amount adjustment valve of the present invention. The intake manifold 8 includes a surge tank 8a and a plurality of branch passages 8b that branch from the surge tank 8a to each cylinder. The exhaust passage 3 is provided with a turbine 5b of the supercharger 5 and a catalyst 10 for purifying exhaust gas. The engine 1 has a known configuration, combusts a mixture of fuel and intake air, and discharges the exhaust after combustion to the exhaust passage 3. In the supercharger 5, the turbine 5 b rotates by the flow of exhaust gas, and the compressor 5 a rotates in conjunction with the rotation of the turbine 5 b, thereby boosting the intake air in the intake passage 2.

このエンジンシステムは、排気還流装置（ＥＧＲ装置）２１を備える。この装置２１は、各気筒から排気通路３へ排出される排気の一部を排気還流ガス（ＥＧＲガス）として吸気通路２へ流して各気筒へ還流させるための排気還流通路（ＥＧＲ通路）２２と、ＥＧＲ通路２２に設けられ、ＥＧＲガスを冷却するための排気還流クーラ（ＥＧＲクーラ）２３と、ＥＧＲクーラ２３より下流のＥＧＲ通路２２に設けられ、ＥＧＲガスの流量を調節するための排気還流弁（ＥＧＲ弁）２４とを含む。ＥＧＲ通路２２は、ＥＧＲ弁２４より上流の上流側ＥＧＲ通路２２Ａを含み、ＥＧＲ弁２４より下流の部分は、第１下流側排気還流通路（第１下流側ＥＧＲ通路）２２Ｂと第２下流側排気還流通路（第２下流側ＥＧＲ通路）２２Ｃに分岐される。第１下流側ＥＧＲ通路２２Ｂは、スロットル装置７より下流の吸気通路２（吸気マニホルド８）に接続される。第２下流側ＥＧＲ通路２２Ｃは、スロットル装置７及びコンプレッサ５ａより上流の吸気通路２に接続される。ＥＧＲ通路２２は、上流側ＥＧＲ通路２２Ａの上流端に開口する還流入口２２ａと、第１下流側ＥＧＲ通路２２Ｂの下流端に開口する還流第１出口２２ｂと、第２下流側ＥＧＲ通路２２Ｃの下流端に開口する還流第２出口２２ｃとを含む。そして、還流入口２２ａは触媒１０より下流の排気通路３に連通し、還流第１出口２２ｂはスロットル装置７より下流の吸気通路２（吸気マニホルド８の各分岐通路８ｂ）に連通し、還流第２出口２２ｃはコンプレッサ５ａより上流の吸気通路２に連通する。この実施形態で、第１下流側ＥＧＲ通路２２Ｂの下流部は、同通路２２Ｂを流れるＥＧＲガスを各分岐通路８ｂへ分配するために４つの還流第１出口２２ｂを含む分配管２６となっている。複数の還流第１出口２２ｂが各分岐通路８ｂにそれぞれ連通するのは、ＥＧＲガスを各分岐通路８ｂへ均等に導入するためである。 This engine system includes an exhaust gas recirculation device (EGR device) 21. This device 21 includes an exhaust gas recirculation passage (EGR passage) 22 for flowing a part of exhaust discharged from each cylinder to the exhaust passage 3 as exhaust gas recirculation gas (EGR gas) to the intake passage 2 and recirculating it to each cylinder. The exhaust gas recirculation cooler (EGR cooler) 23 provided in the EGR passage 22 for cooling the EGR gas, and the exhaust gas recirculation valve provided in the EGR passage 22 downstream of the EGR cooler 23 for adjusting the flow rate of the EGR gas. (EGR valve) 24. The EGR passage 22 includes an upstream EGR passage 22A upstream from the EGR valve 24, and a portion downstream from the EGR valve 24 includes a first downstream exhaust recirculation passage (first downstream EGR passage) 22B and a second downstream exhaust. The flow is branched to the reflux passage (second downstream EGR passage) 22C. The first downstream EGR passage 22B is connected to the intake passage 2 (intake manifold 8) downstream from the throttle device 7. The second downstream EGR passage 22C is connected to the intake passage 2 upstream of the throttle device 7 and the compressor 5a. The EGR passage 22 includes a reflux inlet 22a that opens to the upstream end of the upstream EGR passage 22A, a reflux first outlet 22b that opens to the downstream end of the first downstream EGR passage 22B, and a downstream of the second downstream EGR passage 22C. And a reflux second outlet 22c opening at the end. The recirculation inlet 22a communicates with the exhaust passage 3 downstream from the catalyst 10, and the recirculation first outlet 22b communicates with the intake passage 2 (each branch passage 8b of the intake manifold 8) downstream from the throttle device 7, The outlet 22c communicates with the intake passage 2 upstream from the compressor 5a. In this embodiment, the downstream portion of the first downstream EGR passage 22B is a distribution pipe 26 including four reflux first outlets 22b for distributing the EGR gas flowing through the passage 22B to each branch passage 8b. . The reason why the plurality of first reflux outlets 22b communicate with the respective branch passages 8b is to introduce the EGR gas evenly into the respective branch passages 8b.

この実施形態で、ＥＧＲ弁２４は、開度可変な電動弁により構成される。このＥＧＲ弁２４として、大流量、高応答及び高分解能の特性を有することが望ましい。そこで、この実施形態では、ＥＧＲ弁２４の構造として、例えば、特許第５７５９６４６号公報に記載される「二重偏心弁」を基本構成として採用することができる。この二重偏心弁は、大流量制御に対応して構成される。ここでは、ＥＧＲ弁２４の詳しい説明は省略する。 In this embodiment, the EGR valve 24 is configured by an electrically operated valve having a variable opening. The EGR valve 24 desirably has characteristics of a large flow rate, high response, and high resolution. Therefore, in this embodiment, as a structure of the EGR valve 24, for example, a “double eccentric valve” described in Japanese Patent No. 5759646 can be adopted as a basic configuration. This double eccentric valve is configured for large flow control. Here, detailed description of the EGR valve 24 is omitted.

この実施形態において、ＥＧＲ通路２２の分岐部分には、三方弁２７が設けられる。この三方弁２７は、上流側ＥＧＲ通路２２Ａを流れるＥＧＲガスを、第１下流側ＥＧＲ通路２２Ｂと第２下流側ＥＧＲ通路２２Ｃへ選択的に流すために流路を切り替えるように構成される。三方弁２７は、第１ポート２７ａ、第２ポート２７ｂ及び第３ポート２７ｃを含む。そして、上流側ＥＧＲ通路２２Ａの一端が第１ポート２７ａに接続され、第１下流側ＥＧＲ通路２２Ｂの一端が第２ポート２７ｂに接続され、第２下流側ＥＧＲ通路２２Ｃの一端が第３ポート２７ｃに接続される。三方弁２７は、オン・オフ駆動されることにより、上流側ＥＧＲ通路２２Ａから第１ポート２７ａに導出されるＥＧＲガスの流れを、第１下流側ＥＧＲ通路２２Ｂと第２下流側ＥＧＲ通路２２Ｃとの間で選択的に切替えるようになっている。すなわち、三方弁２７がオフ駆動されることで、第３ポート２７ｃが遮断され、第１ポート２７ａと第２ポート２７ｂが連通し、還流入口２２ａから上流側ＥＧＲ通路２２Ａに流入するＥＧＲガスが、還流第１出口２２ｂから各分岐通路８ｂへ流れるようになっている（いわゆる高圧ループタイプの機能。以下、便宜的に「ＨＰＬ機能」という。）。一方、三方弁２７がオン駆動されることで、第２ポート２７ｂが遮断され、第１ポート２７ａと第３ポート２７ｃが連通し、還流入口２２ａから上流側ＥＧＲ通路２２Ａに流入するＥＧＲガスが、還流第２出口２２ｃからコンプレッサ５ａより上流の吸気通路２へ流れるようになっている（いわゆる低圧ループタイプの機能。以下、便宜的に「ＬＰＬ機能」という。）。すなわち、このＥＧＲ装置２１は、触媒１０より下流の排気通路３からスロットル装置７より下流の吸気通路２（吸気マニホルド８の各分岐通路８ｂ）へＥＧＲガスを流すことができるＨＰＬ機能と、触媒１０より下流の排気通路３からスロットル装置７及びコンプレッサ５ａより上流かつエアクリーナ４より下流の吸気通路２へＥＧＲガスを流すことができるＬＰＬ機能とを兼ね備える。この実施形態で、三方弁２７は、本発明の流路切替弁の一例に相当する。 In this embodiment, a three-way valve 27 is provided at the branch portion of the EGR passage 22. The three-way valve 27 is configured to switch the flow path so that the EGR gas flowing through the upstream EGR passage 22A selectively flows into the first downstream EGR passage 22B and the second downstream EGR passage 22C. The three-way valve 27 includes a first port 27a, a second port 27b, and a third port 27c. One end of the upstream EGR passage 22A is connected to the first port 27a, one end of the first downstream EGR passage 22B is connected to the second port 27b, and one end of the second downstream EGR passage 22C is connected to the third port 27c. Connected to. When the three-way valve 27 is turned on / off, the flow of the EGR gas led out from the upstream EGR passage 22A to the first port 27a is changed to the first downstream EGR passage 22B and the second downstream EGR passage 22C. Are selectively switched between. That is, by turning off the three-way valve 27, the third port 27c is shut off, the first port 27a and the second port 27b are communicated, and the EGR gas flowing into the upstream EGR passage 22A from the reflux inlet 22a It flows from the first reflux outlet 22b to each branch passage 8b (a so-called high-pressure loop type function, hereinafter referred to as an “HPL function” for convenience). On the other hand, when the three-way valve 27 is turned on, the second port 27b is shut off, the first port 27a and the third port 27c are communicated, and the EGR gas flowing into the upstream EGR passage 22A from the reflux inlet 22a It flows from the recirculation second outlet 22c to the intake passage 2 upstream of the compressor 5a (a so-called low-pressure loop type function; hereinafter referred to as “LPL function” for convenience). That is, the EGR device 21 has an HPL function that allows EGR gas to flow from the exhaust passage 3 downstream of the catalyst 10 to the intake passage 2 (each branch passage 8b of the intake manifold 8) downstream of the throttle device 7, and the catalyst 10 It also has an LPL function that allows EGR gas to flow from the exhaust passage 3 downstream from the throttle device 7 and the compressor 5 a to the intake passage 2 downstream from the air cleaner 4. In this embodiment, the three-way valve 27 corresponds to an example of the flow path switching valve of the present invention.

次に、三方弁２７の構成について以下に詳しく説明する。図２に、三方弁２７を斜視図により示す。図３に、三方弁２７を正面図により示す。図４に、三方弁２７を背面図により示す。図５に、三方弁２７を平面図により示す。図６に、三方弁２７を底面図により示す。図７に、三方弁２７を右側面図により示す。図８に、三方弁２７を左側面図により示す。図９に、三方弁２７の一動作を図８のＡ−Ａ線断面図により示す。図１０に、三方弁２７の別の動作を図８のＡ−Ａ線断面図により示す。図２〜図１０に示すように、三方弁２７は、ハウジング４１と、ハウジング４１の内部に設けられ、ＥＧＲ弁２４より上流のＥＧＲ通路２２（上流側ＥＧＲ通路２２Ａ）からのＥＧＲガスを導入するための上流側通路部４２と、ハウジング４１の内部に設けられ、第１下流側ＥＧＲ通路２２ＢへＥＧＲガスを導出するための第１下流側通路部４３と、ハウジング４１の内部に設けられ、第２下流側ＥＧＲ通路２２ＣへＥＧＲガスを導出するための第２下流側通路部４４とを備える。上流側通路部４２の入口が第１ポート２７ａであり、第１下流側通路部４３の出口が第２ポート２７ｂであり、第２下流側通路部４４の出口が第３ポート２７ｃである。 Next, the configuration of the three-way valve 27 will be described in detail below. FIG. 2 is a perspective view of the three-way valve 27. FIG. 3 is a front view of the three-way valve 27. FIG. 4 shows the three-way valve 27 in a rear view. FIG. 5 shows the three-way valve 27 in a plan view. FIG. 6 shows the three-way valve 27 in a bottom view. FIG. 7 is a right side view of the three-way valve 27. FIG. 8 is a left side view of the three-way valve 27. FIG. 9 shows an operation of the three-way valve 27 by a cross-sectional view taken along line AA in FIG. FIG. 10 shows another operation of the three-way valve 27 by a cross-sectional view taken along line AA in FIG. As shown in FIGS. 2 to 10, the three-way valve 27 is provided inside the housing 41 and the housing 41, and introduces EGR gas from the EGR passage 22 (upstream EGR passage 22 </ b> A) upstream from the EGR valve 24. Provided in the housing 41, the first downstream passage portion 43 for leading the EGR gas to the first downstream EGR passage 22B, the housing 41, And a second downstream passage portion 44 for deriving EGR gas to the downstream EGR passage 22C. The inlet of the upstream passage portion 42 is the first port 27a, the outlet of the first downstream passage portion 43 is the second port 27b, and the outlet of the second downstream passage portion 44 is the third port 27c.

この実施形態で、ＥＧＲ弁２４は、三方弁２７に対し一体的に固定される。すなわち、図２〜図１０に示すように、ハウジング４１の第１ポート２７ａには、ＥＧＲ弁２４のハウジング３１が固定される。このハウジング３１の中の流路３１ａには、弁座３２が設けられると共に、弁座３２に着座可能に設けられた弁体３３が回転軸３４を中心に回動可能に設けられる。図９、図１０において、ＥＧＲ弁２４は、弁体３３が弁座３２に着座した閉弁状態を示す。 In this embodiment, the EGR valve 24 is integrally fixed to the three-way valve 27. That is, as shown in FIGS. 2 to 10, the housing 31 of the EGR valve 24 is fixed to the first port 27 a of the housing 41. A valve seat 32 is provided in the flow path 31 a in the housing 31, and a valve body 33 provided so as to be able to be seated on the valve seat 32 is provided so as to be rotatable about a rotation shaft 34. 9 and 10, the EGR valve 24 shows a closed state in which the valve element 33 is seated on the valve seat 32.

図９、図１０に示すように、第１下流側通路部４３には、第１弁座４３ａが設けられると共に、第１弁座４３ａに対応して、板状をなす第１弁体４５が設けられる。第１弁体４５は、第１下流側通路部４３を開閉するために、第１回転軸４６を中心に揺動可能に設けられると共に、第１弁座４３ａの下流側にて第１弁座４３ａに着座可能に設けられる。第１弁座４３ａは、第１下流側通路部４３において、斜めに形成される。また、第１下流側通路部４３において、第１回転軸４６は、ＥＧＲガスの流れからずれた位置、すなわち第１下流側通路部４３の中心から外側へ離れた位置に配置される。 As shown in FIGS. 9 and 10, the first downstream passage portion 43 is provided with a first valve seat 43a, and a plate-like first valve body 45 corresponding to the first valve seat 43a is provided. Provided. The first valve body 45 is provided so as to be swingable about the first rotation shaft 46 in order to open and close the first downstream passage portion 43, and at the downstream side of the first valve seat 43a, the first valve seat 45a is provided. 43a is provided so that it can be seated. The first valve seat 43 a is formed obliquely in the first downstream passage portion 43. In the first downstream passage portion 43, the first rotation shaft 46 is disposed at a position deviated from the flow of EGR gas, that is, at a position away from the center of the first downstream passage portion 43.

図９、図１０に示すように、第２下流側通路部４４には、第２弁座４４ａが設けられると共に、第２弁座４４ａに対応して、板状をなす第２弁体４７が設けられる。第２弁体４７は、第２下流側通路部４４を開閉するために、第２回転軸４８を中心に揺動可能に設けられると共に、第２弁座４４ａの下流側にて第２弁座４４ａに着座可能に設けられる。第２弁座４４ａは、第２下流側通路部４４において、斜めに形成される。また、第２下流側通路部４４において、第２回転軸４８は、ＥＧＲガスの流れからずれた位置、すなわち第２下流側通路部４４の中心から外側へ離れた位置に配置される。 As shown in FIGS. 9 and 10, the second downstream passage portion 44 is provided with a second valve seat 44a, and a second valve body 47 having a plate shape corresponding to the second valve seat 44a. Provided. The second valve body 47 is provided so as to be able to swing around the second rotating shaft 48 in order to open and close the second downstream passage portion 44, and at the downstream side of the second valve seat 44a, the second valve seat 44a. 44a is slidably provided. The second valve seat 44 a is formed obliquely in the second downstream side passage portion 44. In the second downstream passage portion 44, the second rotation shaft 48 is disposed at a position deviated from the flow of EGR gas, that is, at a position away from the center of the second downstream passage portion 44.

図２〜図１０に示すように、この三方弁２７は、第１弁体４５と第２弁体４７をそれぞれ連動して開弁及び閉弁させるための連動駆動機構５０を備える。この連動駆動機構５０は、図１０に示すように、第１弁体４５が開弁するときに第２弁体４７が第２弁座４４ａに着座して閉弁する第１の動作状態と、図９に示すように、第２弁体４７が開弁するときに第１弁体４５が第１弁座４３ａに着座して閉弁する第２の動作状態とを含み、第１の動作状態と第２の動作状態とを切り替えるように構成される。すなわち、連動駆動機構５０は、第１弁体４５と第２弁体４７のうちの一方が開弁するときに他方が閉弁するように構成される。加えて、この実施形態で、連動駆動機構５０は、第１の動作状態と第２の動作状態との間に、第１弁体４５と第２弁体４７の双方を閉弁する第３の動作状態を含むように構成される。 As shown in FIGS. 2 to 10, the three-way valve 27 includes an interlocking drive mechanism 50 for opening and closing the first valve body 45 and the second valve body 47 in conjunction with each other. As shown in FIG. 10, the interlock drive mechanism 50 includes a first operation state in which the second valve body 47 is seated on the second valve seat 44a and closed when the first valve body 45 is opened, As shown in FIG. 9, when the second valve body 47 opens, the first valve body 45 sits on the first valve seat 43a and closes, and the first operation state And the second operating state. That is, the interlocking drive mechanism 50 is configured such that when one of the first valve body 45 and the second valve body 47 is opened, the other is closed. In addition, in this embodiment, the interlocking drive mechanism 50 is a third valve that closes both the first valve body 45 and the second valve body 47 between the first operation state and the second operation state. It is configured to include an operating state.

連動駆動機構５０の構成について詳しく説明する。図２〜図１０に示すように、第１回転軸４６の両端部は、第１軸受５１を介してハウジング４１に回転可能に支持される。また、第２回転軸４８の両端部は、第２軸受５２を介してハウジング４１に回転可能に支持される。連動駆動機構５０は、負圧の供給を受けて動作するダイアフラムアクチュエータ（以下、単に「アクチュエータ」という。）５６と、第１回転軸４６の一端部に固定されたリンク５７及び第１レバー５８と、第２回転軸４８の一端部に固定された第２レバー５９と、第２レバー５９の先端に回動可能に支持された連結カム６０とを備える。 The configuration of the interlocking drive mechanism 50 will be described in detail. 2-10, the both ends of the 1st rotating shaft 46 are rotatably supported by the housing 41 via the 1st bearing 51. As shown in FIG. Further, both end portions of the second rotating shaft 48 are rotatably supported by the housing 41 via the second bearing 52. The interlocking drive mechanism 50 includes a diaphragm actuator (hereinafter simply referred to as “actuator”) 56 that operates by receiving a negative pressure, a link 57 and a first lever 58 fixed to one end of the first rotating shaft 46. The second lever 59 is fixed to one end of the second rotating shaft 48, and the connecting cam 60 is rotatably supported at the tip of the second lever 59.

アクチュエータ５６は、ハウジング４１に対しブラケット６１を介して支持される。このアクチュエータ５６は周知の構造を有し、負圧ポート５６ａから内部へ負圧が導入されることにより作動ロッド５６ｂが収縮し、内部への負圧の導入が遮断されることにより作動ロッド５６ｂが伸長するようになっている。この実施形態では、アクチュエータ５６を作動させるための負圧として、吸気通路２で発生する負圧が利用されるようになっている。このアクチュエータ５６に対する負圧の導入と遮断は、所定のＶＳＶ（図示略）をオン・オフすることで制御されるようになっている。 The actuator 56 is supported with respect to the housing 41 via a bracket 61. The actuator 56 has a well-known structure, and when the negative pressure is introduced from the negative pressure port 56a to the inside, the operating rod 56b contracts, and when the introduction of the negative pressure to the inside is interrupted, the operating rod 56b is It is designed to stretch. In this embodiment, the negative pressure generated in the intake passage 2 is used as the negative pressure for operating the actuator 56. The introduction and interruption of the negative pressure with respect to the actuator 56 is controlled by turning on / off a predetermined VSV (not shown).

リンク５７は、第１端部５７ａと第２端部５７ｂを有し、ほぼ中央部にて第１回転軸４６に固定される。第１レバー５８は、リンク５７の外側にて第１回転軸４６に固定される。リンク５７の第１端部５７ａは、作動ロッド５６ｂの先端部に対し回動可能に連結される。第１レバー５８の先端は、作動ロッド５６ｂの先端に係合可能に配置される。連結カム６０は、長孔６０ａを有し、一端部が第２レバー５９の先端部に対し回動可能に連結される。また、長孔６０ａには、リンク５７の第２端部５７ｂがスライド可能に連結される。第１回転軸４６とハウジング４１との間には、第１弁体４５を閉弁方向へ付勢するための第１スプリング６２が設けられる。第１スプリング６２は、本発明の第１の付勢手段の一例に相当する。第２回転軸４８とハウジング４１との間には、第２弁体４７を閉弁方向へ付勢するための第２スプリング６３が設けられる。第２スプリング６３は、本発明の第２の付勢手段の一例に相当する。 The link 57 has a first end portion 57a and a second end portion 57b, and is fixed to the first rotating shaft 46 at a substantially central portion. The first lever 58 is fixed to the first rotation shaft 46 outside the link 57. The first end 57a of the link 57 is rotatably connected to the tip of the operating rod 56b. The tip of the first lever 58 is disposed so as to be engageable with the tip of the operating rod 56b. The connecting cam 60 has a long hole 60 a and one end thereof is connected to the tip of the second lever 59 so as to be rotatable. Further, the second end 57b of the link 57 is slidably connected to the long hole 60a. A first spring 62 for biasing the first valve body 45 in the valve closing direction is provided between the first rotating shaft 46 and the housing 41. The first spring 62 corresponds to an example of the first urging means of the present invention. Between the 2nd rotating shaft 48 and the housing 41, the 2nd spring 63 for urging | biasing the 2nd valve body 47 in the valve closing direction is provided. The second spring 63 corresponds to an example of the second urging means of the present invention.

次に、上記した連動駆動機構５０の動作と第１弁体４５及び第２弁体４７の開閉動作との関係について説明する。図１１に、連動駆動機構５０の第１動作状態と各弁体４５，４７の動作状態をハウジング４１の一部を破断して概略図により示す。図１２に、連動駆動機構５０の第３動作状態と各弁体４５，４７の動作状態をハウジング４１の一部を破断して概略図により示す。図１３に、連動駆動機構５０の第２動作状態と各弁体４５，４７の動作状態をハウジング４１の一部を破断して概略図により示す。先ず、アクチュエータ５６への負圧の供給が遮断されると、図１１に示すように、連動駆動機構５０が第１動作状態となる。すなわち、アクチュエータ５６の作動ロッド５６ｂが最大限に伸長する。このとき、リンク５７は、第１回転軸４６を中心に反時計方向へ回動して右斜め上方へ傾斜する。また、リンク５７及び連結カム６０を介して第２レバー５９が第２回転軸４８と共に時計方向へ回動するが、リンク５７の第２端部５７ｂが連結カム６０の長孔６０ａの上端に係合することで連動駆動機構５０の動きが停止する。これにより、第１弁体４５が開弁し、第２弁体４７が閉弁する。第１弁体４５が開弁するので、ＥＧＲ弁２４から上流側通路部４２に流入したＥＧＲガスは、太矢印で示すように、第１下流側通路部４３へ向けて流れる。この結果、ＥＧＲ装置２１は、触媒１０より下流の排気通路３からスロットル装置７より下流の吸気通路２（吸気マニホルド８の各分岐通路８ｂ）へＥＧＲガスを流すことができるＨＰＬ機能となる。 Next, the relationship between the operation of the interlock drive mechanism 50 and the opening / closing operations of the first valve body 45 and the second valve body 47 will be described. FIG. 11 is a schematic view showing a first operation state of the interlocking drive mechanism 50 and operation states of the valve bodies 45 and 47 with a part of the housing 41 broken away. FIG. 12 is a schematic view showing a third operation state of the interlocking drive mechanism 50 and the operation states of the valve bodies 45 and 47 with a part of the housing 41 broken away. FIG. 13 is a schematic view of the second operation state of the interlocking drive mechanism 50 and the operation states of the valve bodies 45 and 47 with a part of the housing 41 broken away. First, when the supply of negative pressure to the actuator 56 is interrupted, the interlocking drive mechanism 50 enters the first operation state as shown in FIG. That is, the operating rod 56b of the actuator 56 extends to the maximum extent. At this time, the link 57 rotates counterclockwise around the first rotation shaft 46 and tilts obliquely upward to the right. Further, the second lever 59 rotates clockwise together with the second rotation shaft 48 via the link 57 and the connecting cam 60, but the second end portion 57 b of the link 57 is engaged with the upper end of the long hole 60 a of the connecting cam 60. When combined, the movement of the interlocking drive mechanism 50 stops. As a result, the first valve body 45 is opened and the second valve body 47 is closed. Since the first valve body 45 is opened, the EGR gas that has flowed into the upstream passage portion 42 from the EGR valve 24 flows toward the first downstream passage portion 43 as indicated by a thick arrow. As a result, the EGR device 21 has an HPL function that allows EGR gas to flow from the exhaust passage 3 downstream of the catalyst 10 to the intake passage 2 (each branch passage 8b of the intake manifold 8) downstream of the throttle device 7.

第１の動作状態から、アクチュエータ５６へ負圧が供給され始めると、図１２に示すように、連動駆動機構５０は第３動作状態となる。この状態では、アクチュエータ５６の作動ロッド５６ｂが収縮し始めるので、リンク５７が、第１回転軸４６を中心に時計方向へ回動し始める。そして、リンク５７の第２端部５７ｂが連結カム６０の長孔６０ａに沿ってその下端へスライドし、そのスライドの間はリンク５７のトルクが連結カム６０に伝わらない。そして、第２レバー５９は第２回転軸４８と共に第２スプリング６３により時計方向へ回動付勢される。これにより、第１弁体４５と第２弁体４７の双方が閉弁する。このように各弁体４５，４７の双方が閉弁する期間は、連結カム６０の長孔６０ａの長さにより決まる。各弁体４５，４７の双方が閉弁するので、上流側通路部４２と、第１弁座４３ａより下流の第１下流側通路部４３と、第２弁座４４ａより下流の第２下流側通路部４４との間の連通がそれぞれ遮断される。 When negative pressure starts to be supplied to the actuator 56 from the first operation state, the interlocking drive mechanism 50 enters the third operation state as shown in FIG. In this state, the operating rod 56b of the actuator 56 starts to contract, and the link 57 starts to rotate clockwise about the first rotation shaft 46. Then, the second end portion 57b of the link 57 slides to the lower end along the long hole 60a of the connection cam 60, and the torque of the link 57 is not transmitted to the connection cam 60 during the slide. The second lever 59 is urged to rotate clockwise along with the second rotating shaft 48 by the second spring 63. Thereby, both the 1st valve body 45 and the 2nd valve body 47 close. Thus, the period during which both valve bodies 45 and 47 are closed is determined by the length of the long hole 60 a of the connecting cam 60. Since both valve bodies 45 and 47 are closed, the upstream side passage portion 42, the first downstream side passage portion 43 downstream from the first valve seat 43a, and the second downstream side downstream from the second valve seat 44a. Communication with the passage portion 44 is blocked.

その後、アクチュエータ５６へ更に負圧が供給されると、図１３に示すように、連動駆動機構５０は第２動作状態となる。この状態では、アクチュエータ５６の作動ロッド５６ｂが最大限に収縮する。このとき、リンク５７は、第１回転軸４６を中心に更に時計方向へ回動し、リンク５７及び連結カム６０を介して第２レバー５９が第２回転軸４８と共に反時計方向へ回動する。これにより、第１弁体４５が閉弁し、第２弁体４７が開弁する。第２弁体４７が開弁するので、ＥＧＲ弁２４から上流側通路部４２に流入するＥＧＲガスは、太矢印で示すように、第２下流側通路部４４へ向けて流れる。この結果、ＥＧＲ装置２１は、触媒１０より下流の排気通路３からスロットル装置７及びコンプレッサ５ａより上流の吸気通路２へＥＧＲガスを流すことができるＬＰＬ機能となる。 Thereafter, when further negative pressure is supplied to the actuator 56, the interlocking drive mechanism 50 enters the second operation state as shown in FIG. In this state, the operating rod 56b of the actuator 56 contracts to the maximum extent. At this time, the link 57 further rotates clockwise about the first rotation shaft 46, and the second lever 59 rotates together with the second rotation shaft 48 counterclockwise via the link 57 and the connecting cam 60. . As a result, the first valve body 45 is closed and the second valve body 47 is opened. Since the second valve body 47 is opened, the EGR gas flowing from the EGR valve 24 into the upstream passage portion 42 flows toward the second downstream passage portion 44 as indicated by a thick arrow. As a result, the EGR device 21 has an LPL function capable of flowing EGR gas from the exhaust passage 3 downstream from the catalyst 10 to the throttle device 7 and the intake passage 2 upstream from the compressor 5a.

以上説明したこの実施形態におけるＥＧＲ装置２１の三方弁２７の構成によれば、連動駆動機構５０が、第１弁体４５と第２弁体４７を連動して開弁及び閉弁させると共に、第１弁体４５が開弁するときに第２弁体４７が第２弁座４４ａに着座して閉弁する第１の動作状態と、第２弁体４７が開弁するときに第１弁体４５が第１弁座４３ａに着座して閉弁する第２の動作状態とを含み、第１の動作状態と第２の動作状態とを切り替えるように構成される。従って、第１弁体４５と第２弁体４７のうち一方が開弁するときは他方が閉弁するので、その開弁及び閉弁の切り替え時に、第１弁座４３ａより下流の第１下流側通路部４３と第２弁座４４ａより下流の第２下流側通路部４４とが互いに連通することがない。このため、ＬＰＬタイプとＨＰＬタイプとの間で機能を切り替えるときに、第１下流側ＥＧＲ通路２２Ｂと第２下流側ＥＧＲ通路２２Ｃとを互いに連通させることなく流路を切り替えることができる。この結果、ＬＰＬ機能からＨＰＬ機能への切り替え時には、第１下流側ＥＧＲ通路２２Ｂを介して新気がエンジン１（燃焼室）に流入してエンジン１の出力が変動することを防止することができる。一方、ＨＰＬ機能からＬＰＬ機能への切り替え時には、第２下流側ＥＧＲ通路２２Ｃ及び吸気通路２を介してエンジン１（燃焼室）へ過剰にＥＧＲガスが導入されてエミッションが悪化することを防止することができる。 According to the configuration of the three-way valve 27 of the EGR device 21 in this embodiment described above, the interlocking drive mechanism 50 opens and closes the first valve body 45 and the second valve body 47 in conjunction with each other, and A first operating state in which the second valve body 47 is seated on the second valve seat 44a and closed when the one valve body 45 is opened, and the first valve body 47 is opened when the second valve body 47 is opened. 45 includes a second operation state in which the first valve seat 43a is seated and closed, and is configured to switch between the first operation state and the second operation state. Accordingly, when one of the first valve body 45 and the second valve body 47 is opened, the other valve is closed. Therefore, when the valve is opened and closed, the first downstream of the first valve seat 43a is downstream. The side passage portion 43 and the second downstream passage portion 44 downstream from the second valve seat 44a do not communicate with each other. For this reason, when the function is switched between the LPL type and the HPL type, the flow path can be switched without causing the first downstream EGR passage 22B and the second downstream EGR passage 22C to communicate with each other. As a result, at the time of switching from the LPL function to the HPL function, it is possible to prevent the fresh air from flowing into the engine 1 (combustion chamber) through the first downstream EGR passage 22B and changing the output of the engine 1. . On the other hand, when switching from the HPL function to the LPL function, it is possible to prevent the EGR gas from being excessively introduced into the engine 1 (combustion chamber) via the second downstream EGR passage 22C and the intake passage 2 to deteriorate the emission. Can do.

この実施形態における三方弁２７の構成によれば、第１下流側通路部４３では、板状をなす第１弁体４５が第１回転軸４６を中心に揺動可能に設けられると共に、第１弁座４３ａの下流側にて第１弁座４３ａに着座可能に設けられる。同様に、第２下流側通路部４４では、板状をなす第２弁体４７が第２回転軸４８を中心に揺動可能に設けられると共に、第２弁座４４ａの下流側にて第２弁座４４ａに着座可能に設けられる。従って、第１弁体４５が閉弁したときは、第１弁座４３ａを境にした第１下流側通路部４３の上流側と下流側との間の圧力差により、第１弁体４５が第１弁座４３ａに押し付けられる。同様に、第２弁体４７が閉弁したときは、第２弁座４４ａを境にした第２下流側通路部４４の上流側と下流側との間の圧力差により、第２弁体４７が第２弁座４４ａに押し付けられる。このため、各弁体４５，４７の閉弁時に、各弁体４５、４７と対応する各弁座４３ａ，４４ａとの間のシール性を向上させることができる。すなわち、第１弁体４５の閉弁時には、第１弁体４５と第１弁座４３ａとの間のシール性を向上させることができる。また、第２弁体４７の閉弁時に、第２弁体４７と第２弁座４４ａとの間のシール性を向上させることができる。 According to the configuration of the three-way valve 27 in this embodiment, in the first downstream-side passage portion 43, the plate-shaped first valve body 45 is provided so as to be able to swing around the first rotation shaft 46, and the first It is provided so as to be seated on the first valve seat 43a on the downstream side of the valve seat 43a. Similarly, in the second downstream passage portion 44, a plate-shaped second valve body 47 is provided so as to be swingable about the second rotation shaft 48, and at the second downstream side of the second valve seat 44a. It is provided so as to be seated on the valve seat 44a. Therefore, when the first valve body 45 is closed, the first valve body 45 is caused by the pressure difference between the upstream side and the downstream side of the first downstream passage portion 43 with the first valve seat 43a as a boundary. It is pressed against the first valve seat 43a. Similarly, when the second valve body 47 is closed, the second valve body 47 is caused by a pressure difference between the upstream side and the downstream side of the second downstream passage portion 44 with the second valve seat 44a as a boundary. Is pressed against the second valve seat 44a. For this reason, when the valve bodies 45 and 47 are closed, the sealing performance between the valve bodies 45 and 47 and the corresponding valve seats 43a and 44a can be improved. That is, when the first valve body 45 is closed, the sealing performance between the first valve body 45 and the first valve seat 43a can be improved. In addition, when the second valve body 47 is closed, the sealing performance between the second valve body 47 and the second valve seat 44a can be improved.

例えば、図９に示すように、ＬＰＬ機能のときは、第２弁体４７が開弁して第２下流側通路部４４からＥＧＲガス（網掛け矢印で示す。）が導出されるが、過給により吸気圧（白抜き矢印で示す。）が上昇しても、第１弁体４５が第１弁座４３ａに押し付けられるので、第１弁体４５と第１弁座４３ａとの間から吸気が漏れることがない。また、第１下流側通路部４３から上流側通路部４２及び上流側ＥＧＲ通路２２Ａを介して排気通路３へ吸気（新気）が流入することを防止することができる。一方、図１０に示すように、ＨＰＬ機能のときは、第１弁体４５が開弁し、第１下流側通路部４３に作用する負圧によりＥＧＲガス（網掛け矢印で示す。）が導出されるが、負圧（白抜き矢印で示す。）が第２弁体４７に作用し、第２弁体４７が第２弁座４４ａに押し付けられる。このため、第２弁体４７と第２弁座４４ａとの間から吸気が漏れることがない。ここで、各弁体４５，４７又は各弁座４３ａ，４４ａにシール部材を設けても、各弁体４５，４７の開閉時には、各弁体４５，４７が対応する各弁座４３ａ，４４ａに対し摺動することがないので、各弁体４５，４７の開閉応答性に影響を与えることがない。 For example, as shown in FIG. 9, during the LPL function, the second valve body 47 is opened and EGR gas (shown by a shaded arrow) is derived from the second downstream passage portion 44. Even if the intake pressure (indicated by a white arrow) rises due to the supply, the first valve body 45 is pressed against the first valve seat 43a, so that the intake air is drawn from between the first valve body 45 and the first valve seat 43a. Will not leak. In addition, it is possible to prevent intake air (fresh air) from flowing into the exhaust passage 3 from the first downstream passage portion 43 via the upstream passage portion 42 and the upstream EGR passage 22A. On the other hand, as shown in FIG. 10, in the HPL function, the first valve body 45 is opened, and EGR gas (indicated by a shaded arrow) is derived by the negative pressure acting on the first downstream passage portion 43. However, negative pressure (indicated by a white arrow) acts on the second valve body 47, and the second valve body 47 is pressed against the second valve seat 44a. For this reason, intake air does not leak from between the second valve body 47 and the second valve seat 44a. Here, even if each valve body 45, 47 or each valve seat 43a, 44a is provided with a seal member, when the valve body 45, 47 is opened or closed, each valve body 45, 47 has a corresponding valve seat 43a, 44a. Since it does not slide, the open / close response of the valve bodies 45 and 47 is not affected.

この実施形態における三方弁２７の構成によれば、連動駆動機構５０につき、第１の動作状態と第２の動作状態との間に第３の動作状態が設けられるので、第１弁体４５と第２弁体４７の開弁及び閉弁の切り替え時に、第１弁体４５と第２弁体４７の双方が一旦閉弁する。従って、開弁及び閉弁の切り替え時に、第１弁座４３ａより下流の第１下流側通路部４３と第２弁座４４ａより下流の第２下流側通路部４４との連通が確実に遮断される。このため、ＬＰＬタイプとＨＰＬタイプとの間で機能を切り替えるときに、第１下流側ＥＧＲ通路２２Ｂと第２下流側ＥＧＲ通路２２Ｃとの間の連通を確実に防止することができる。 According to the configuration of the three-way valve 27 in this embodiment, the interlocking drive mechanism 50 is provided with the third operation state between the first operation state and the second operation state. When the second valve body 47 is opened and closed, both the first valve body 45 and the second valve body 47 are once closed. Therefore, when the valve is opened and closed, the communication between the first downstream passage portion 43 downstream from the first valve seat 43a and the second downstream passage portion 44 downstream from the second valve seat 44a is reliably blocked. The For this reason, when the function is switched between the LPL type and the HPL type, communication between the first downstream EGR passage 22B and the second downstream EGR passage 22C can be reliably prevented.

この実施形態における三方弁２７の構成によれば、第１下流側通路部４３において、第１回転軸４６がＥＧＲガスの流れからずれた位置に配置され、第２下流側通路部４４において、第２回転軸４８が、ＥＧＲガスの流れからずれた位置に配置されるので、第１回転軸４６と第２回転軸４８がＥＧＲガスに曝され難くなる。このため、各回転軸４６，４８や各軸受５１，５２に対する凝縮水やデポジットの付着を防止することができ、それら回転軸４６，４８及び軸受５１，５２の腐食や固着を防止することができる。 According to the configuration of the three-way valve 27 in this embodiment, the first rotary shaft 46 is disposed at a position shifted from the flow of the EGR gas in the first downstream passage portion 43, and the second downstream passage portion 44 has the first Since the two rotation shafts 48 are disposed at positions deviated from the flow of the EGR gas, the first rotation shaft 46 and the second rotation shaft 48 are not easily exposed to the EGR gas. For this reason, it is possible to prevent the condensed water and deposits from adhering to the rotary shafts 46 and 48 and the bearings 51 and 52, and to prevent the rotary shafts 46 and 48 and the bearings 51 and 52 from corroding and sticking. .

この実施形態における三方弁２７の構成によれば、第１弁体４５が第１スプリング６２により閉弁方向へ付勢され、第２弁体４７が第２スプリング６３により閉弁方向へ付勢される。従って、閉弁時には、各スプリング６２，６３の付勢力により、各弁体４５，４７が対応する弁座４３ａ，４４ａに押さえ付けられる。このため、第１弁体４５又は第２弁体４７が閉弁したときに、各弁体４５，４７と対応する各弁座４３ａ，４４ａとの間のシール性を向上させることができる。 According to the configuration of the three-way valve 27 in this embodiment, the first valve body 45 is biased in the valve closing direction by the first spring 62, and the second valve body 47 is biased in the valve closing direction by the second spring 63. The Therefore, when the valve is closed, the valve bodies 45 and 47 are pressed against the corresponding valve seats 43a and 44a by the urging force of the springs 62 and 63. For this reason, when the 1st valve body 45 or the 2nd valve body 47 closes, the sealing performance between each valve body 45 and 47 and each valve seat 43a, 44a corresponding can be improved.

この実施形態における三方弁２７の構成によれば、ＥＧＲ弁２４が一体的に設けられるので、三方弁２７とＥＧＲ弁２４を一つのアッセンブリとして取り扱うことができ、それら三方弁２７及びＥＧＲ弁２４のＥＧＲ通路２２に対する組み付け作業を簡易化することができる。 According to the configuration of the three-way valve 27 in this embodiment, since the EGR valve 24 is provided integrally, the three-way valve 27 and the EGR valve 24 can be handled as one assembly, and the three-way valve 27 and the EGR valve 24 The assembling work for the EGR passage 22 can be simplified.

なお、この発明は前記実施形態に限定されるものではなく、発明の趣旨を逸脱することのない範囲で構成の一部を適宜変更して実施することもできる。 In addition, this invention is not limited to the said embodiment, A part of structure can also be changed suitably and implemented in the range which does not deviate from the meaning of invention.

（１）前記実施形態では、三方弁２７の連動駆動機構５０につき、第１の動作状態、第２の動作状態及び第３の動作状態を含む構成としたが、第３の動作状態を省略することができる。 (1) In the above embodiment, the interlock drive mechanism 50 of the three-way valve 27 is configured to include the first operation state, the second operation state, and the third operation state, but the third operation state is omitted. be able to.

（２）前記実施形態では、三方弁２７の連動駆動機構５０を、ダイアフラムアクチュエータ５６により駆動するように構成したが、ダイアフラムアクチュエータ５６の代わりにモータにより駆動するように構成することもできる。 (2) In the above embodiment, the interlocking drive mechanism 50 of the three-way valve 27 is configured to be driven by the diaphragm actuator 56, but it can also be configured to be driven by a motor instead of the diaphragm actuator 56.

（３）前記実施形態では、ＥＧＲ弁２４を三方弁２７に一体的に設けたが、ＥＧＲ弁を三方弁と別に設けることもできる。 (3) In the above embodiment, the EGR valve 24 is provided integrally with the three-way valve 27. However, the EGR valve may be provided separately from the three-way valve.

この発明は、いわゆる高圧ループタイプと低圧ループタイプの両方を備え、両タイプを必要に応じて切り替えて使用するように構成したＥＧＲ装置に利用することができる。 The present invention can be applied to an EGR apparatus that includes both a so-called high-pressure loop type and a low-pressure loop type, and is configured to switch both types as necessary.

１エンジン
２吸気通路
３排気通路
７スロットル装置（吸気量調節弁）
２１ＥＧＲ装置（排気還流装置）
２２ＥＧＲ通路（排気還流通路）
２２Ａ上流側ＥＧＲ通路（上流側排気還流通路）
２２Ｂ第１下流側ＥＧＲ通路（第１下流側排気還流通路）
２２Ｃ第２下流側ＥＧＲ通路（第２下流側排気還流通路）
２４ＥＧＲ弁（排気還流弁）
２７三方弁（流路切替え弁）
４１ハウジング
４２上流側通路部
４３第１下流側通路部
４３ａ第１弁座
４４第２下流側通路部
４４ａ第２弁座
４５第１弁体
４６第１回転軸
４７第２弁体
４８第２回転軸
５０連動駆動機構
６２第１スプリング（第１の付勢手段）
６３第２スプリング（第２の付勢手段） 1 Engine 2 Intake passage 3 Exhaust passage 7 Throttle device (intake air amount adjustment valve)
21 EGR device (exhaust gas recirculation device)
22 EGR passage (exhaust gas recirculation passage)
22A Upstream EGR passage (Upstream exhaust recirculation passage)
22B First downstream EGR passage (first downstream exhaust recirculation passage)
22C Second downstream EGR passage (second downstream exhaust recirculation passage)
24 EGR valve (exhaust gas recirculation valve)
27 Three-way valve (flow path switching valve)
41 Housing 42 Upstream passage portion 43 First downstream passage portion 43a First valve seat 44 Second downstream passage portion 44a Second valve seat 45 First valve body 46 First rotating shaft 47 Second valve body 48 Second rotation Shaft 50 Interlocking drive mechanism 62 First spring (first biasing means)
63 Second spring (second biasing means)

Claims

An intake passage for introducing intake air into the engine;
An intake air amount adjusting valve provided in the intake passage for adjusting the intake air amount in the intake passage;
An exhaust gas recirculation passage for causing a part of the exhaust gas led out from the engine to the exhaust air passage to flow into the intake air passage as exhaust gas recirculation gas and recirculate to the engine;
An exhaust gas recirculation valve provided in the exhaust gas recirculation passage for adjusting the flow rate of the exhaust gas recirculation gas;
The exhaust gas recirculation passage downstream from the exhaust gas recirculation valve is branched into a first downstream exhaust recirculation passage and a second downstream exhaust recirculation passage;
The first downstream exhaust recirculation passage is connected to the intake passage downstream from the intake air amount adjustment valve, and the second downstream exhaust recirculation passage is connected to the intake passage upstream from the intake air amount adjustment valve. The exhaust gas recirculation device is provided at a branch portion of the exhaust gas recirculation passage, and the exhaust gas recirculation gas flowing through the exhaust gas recirculation passage is supplied to the first downstream exhaust recirculation passage and the second downstream exhaust recirculation passage. A flow path switching valve configured to switch flow paths for selective flow,
A housing;
An upstream passage portion provided in the housing for introducing the exhaust gas recirculation gas flowing from the exhaust gas recirculation valve;
A first downstream passage portion provided in the housing for leading the exhaust recirculation gas to the first downstream exhaust recirculation passage;
A second downstream passage portion provided in the housing for leading the exhaust recirculation gas to the second downstream exhaust recirculation passage;
A first valve seat provided in the first downstream passage portion;
In order to open and close the first downstream passage portion, it is provided so as to be swingable around a first rotating shaft, and is provided so as to be seated on the first valve seat on the downstream side of the first valve seat. A plate-shaped first valve body;
A second valve seat provided in the second downstream passage portion;
In order to open and close the second downstream passage portion, it is provided so as to be swingable about the second rotation shaft, and is provided so as to be seated on the second valve seat on the downstream side of the second valve seat. A plate-shaped second valve body;
The first valve body and the second valve body are opened and closed in conjunction with each other, and when the first valve body is opened, the second valve body is seated on the second valve seat and closed. A first operating state in which the valve is operated, and a second operating state in which the first valve body is seated on the first valve seat and is closed when the second valve body is opened. A flow path switching valve for an exhaust gas recirculation apparatus, comprising: an interlocking drive mechanism configured to switch between the operation state and the second operation state.

The interlock drive mechanism includes a third operation state in which both the first valve body and the second valve body are closed between the first operation state and the second operation state. The flow path switching valve of the exhaust gas recirculation apparatus according to claim 1, wherein the flow path switching valve is configured.

In the first downstream passage portion, the first rotation shaft is disposed at a position shifted from the flow of the exhaust gas recirculation gas. In the second downstream passage portion, the second rotation shaft is disposed in the exhaust gas recirculation gas. The flow path switching valve of the exhaust gas recirculation apparatus according to claim 1 or 2, wherein the flow path switching valve is disposed at a position deviated from the flow of the exhaust gas.

A first urging means for urging the first valve body in the valve closing direction; and a second urging means for urging the second valve body in the valve closing direction. The flow path switching valve of the exhaust gas recirculation apparatus according to any one of claims 1 to 3.