JP2015151917A - Intake bypass device of engine with supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suitably remove EGR gas remaining in a pressure equilibrium chamber of an intake bypass valve (ABV) and prevent malfunction of the ABV caused by foreign matter.SOLUTION: An engine with a supercharger and a low pressure loop type EGR device includes an intake bypass passage 41 provided on an intake passage while bypassing a compressor, and an ABV 42 opening and closing the passage 41. The ABV 42 comprises: a valve seat 65 provided in a flow passages 63, 64 of a housing 62; a valve member 66 opening and closing the valve seat 65; a movable member 67 moving the valve member 66; a spring 68 biasing the valve member 66 in the close direction; an electromagnet 69 driving the valve member 66 in the open direction; a pressure equilibrium chamber 71 divided from the flow passage 64 via a diaphragm 70; and a pressure introduction passage 72 provided in the valve member 66 and the movable member 67 and putting the flow passage 63 in communication with the pressure equilibrium chamber 71. A residual gas removal passage 43 for removing EGR gas remaining in the pressure equilibrium chamber 71 is connected at one end to a gas outlet port 79 communicating with the pressure equilibrium chamber 71.

Description

  The present invention relates to an intake bypass device for an engine with a supercharger that is provided in an intake passage of an engine equipped with a supercharger and configured to bypass the flow of intake air.

  Conventionally, it is well known that an exhaust gas recirculation (EGR) device is also provided in an engine equipped with a supercharger. The following Patent Document 1 describes an engine equipped with this type of supercharger and a low-pressure loop EGR device provided on the engine. The supercharger includes a turbine provided in the exhaust passage and a compressor provided in the intake passage and driven by the turbine. Further, in this low pressure loop type EGR device, an EGR passage is provided between an exhaust passage downstream of the turbine and an intake passage upstream of the compressor, and an EGR valve is provided in the EGR passage. In this EGR device, the EGR gas recirculation amount is limited by closing the EGR valve as necessary in order to prevent corrosion due to condensed water generated in the EGR passage while responding to strict NOx reduction requirements. It is like that.

  Here, if the pressure difference between the inlet and the outlet of the compressor becomes too large, the air flow becomes unstable on the blade surface of the compressor, and surging may occur that causes self-excited vibration in the air flow. Therefore, an intake bypass device is provided to prevent this surging. The intake bypass device includes an intake bypass passage that bypasses between an intake passage upstream of the compressor and an intake passage downstream of the compressor, and an intake bypass valve provided in the intake bypass passage. Then, by opening the intake bypass valve as necessary, the pressure difference between the inlet and the outlet of the compressor can be reduced, and surging can be prevented. It is conceivable to provide a low-pressure loop EGR device even in an engine with a supercharger equipped with this type of intake bypass device.

An example of this type of intake bypass valve is described in Patent Document 2 below. FIG. 8 shows a schematic configuration of an intake bypass valve (hereinafter referred to as “ABV”) 91 in a sectional view. The ABV 91 installed in the casing 61 is arranged vertically so that an opening / closing direction of a later-described valve member 66 is a vertical direction (vertical direction). An intake bypass passage 41 is formed in the casing 61. The ABV 91 has a cylindrical shape provided between the housing 62, an inflow path 63 and an outflow path 64 that constitute a flow path provided in the housing 62 and communicated with the intake bypass passage 41, and the inflow path 63 and the outflow path 64. The valve seat 65, a hollow cap-shaped valve member 66 that opens and closes the valve seat 65, a columnar movable member 67 that moves the valve member 66 relative to the valve seat 65, and the valve member 66 together with the movable member 67 A spring 68 corresponding to an example of an elastic member biased in the closing direction seated on 65, and a drive for driving the valve member 66 in the opening direction opposite to the closing direction together with the movable member 67 against the biasing force of the spring 68. An electromagnet 69 corresponding to an example of a member, a pressure flat provided between a housing 62 and a valve member 66 and partitioned with respect to the outflow path 64 via a diaphragm 70 corresponding to an example of a pressure responsive member. The chamber 71, provided in the valve member 66 and the movable member 67, and a pressure introducing passage 72 for communicating the inlet channel 63 into the pressure equalization chamber 71. The movable member 67 is formed of a magnetic material. In the ABV 91, in a closed state in which the valve member 66 is seated on the valve seat 65, the pressure of the intake air applied to the valve member 66 side and the pressure balance chamber 71 side is balanced. The valve member 66 is provided with a shielding plate 73 having a vent hole 73a for reducing the dynamic pressure of intake air acting on the pressure balance chamber 71. The shielding plate 73 reduces the dynamic pressure of the intake air acting on the pressure equilibrium chamber 71 when the valve member 66 starts to open, shortens the valve opening time of the valve member 66, and improves the valve opening response. It has become. Further, a hole 69a is provided at the center of the electromagnet 69, and the movable member 67 is loosely fitted into the hole 69a through a minute gap 75 and incorporated. The hole 69 a is for allowing the movable member 67 to move up and down inside the electromagnet 69, and an escape chamber 74 is formed above the movable member 67. The gap 75 is formed between the outer periphery of the movable member 67 and the inner periphery of the hole 69a, and allows the movable member 67 to slide relative to the inner periphery of the hole 69a. A mounting hole 77 is formed in the casing 61 at a concentric position above the valve seat 65. The inner diameter of the mounting hole 77 is larger than the outer diameter of the valve seat 65.

  Here, in the engine system with a supercharger provided with the low pressure loop type EGR device, it is assumed that the intake bypass device described in Patent Literature 2 is provided. In this case, when the EGR valve is opened in the supercharging region where the supercharger operates and EGR gas is allowed to flow from the EGR passage to the intake passage, the outlet pressure of the compressor changes from low pressure to high pressure. Due to this pressure change, EGR gas may flow into the pressure equilibrium chamber 71 of the ABV 91, and the inflowed EGR gas may remain in the pressure equilibrium chamber 71. When the remaining EGR gas is cooled after the engine is stopped, condensed water may be generated due to moisture in the EGR gas. In addition, the movable member 67 and the electromagnet 69 may be corroded by the condensed water, or the condensed water may freeze and the 67 and 69 may be fixed, which may hinder the normal operation of the ABV 91.

  Therefore, in order to remove the EGR gas remaining in the pressure equilibrium chamber 71, for example, it is conceivable to add a new configuration to the ABV 91 as shown in the sectional view of FIG. That is, as shown in FIG. 9, in order to remove the EGR gas remaining in the pressure equilibrium chamber 71 using the escape chamber 74 and the gap 75, the EGR gas may be discharged to the outside of the ABV 91. Therefore, a communication hole 76 that allows the escape chamber 74 to communicate with the outside is formed in the housing 62, and one end of the residual gas removal passage 43 is connected to the outlet of the communication hole 76 via a pipe joint 92. The other end of the residual gas removal passage 43 is connected to an intake passage (not shown) downstream from the throttle valve. According to this configuration, a negative pressure is generated in the intake passage downstream of the throttle valve when the engine is decelerating and the like, so that the negative pressure is reduced to the residual gas removal passage 43, the pipe joint 92, the communication hole 76, and the escape chamber 74. The EGR gas that acts on the pressure equilibrium chamber 71 through the gap 75 and remains in the chamber 71 can be sucked into the intake passage and removed. Further, a check valve 44 can be provided in the residual gas removal passage 43. The check valve 44 allows a gas flow from the pressure balance chamber 71 to the residual gas removal passage 43 and prevents a gas flow from the residual gas removal passage 43 to the pressure balance chamber 71.

JP 2012-229679 A JP 2013-83339 A

  However, in the additional configuration of the ABV 91 shown in FIG. 9, EGR gas flows into the gap 75 and the escape chamber 74 between the movable member 67 and the electromagnet 69 in order to flow EGR gas from the pressure equilibrium chamber 71 to the residual gas removal passage 43. Will flow. The EGR gas contains foreign substances such as fine carbon particles generated by combustion in addition to moisture. The gap 75 is for allowing sliding with respect to the inner periphery of the hole 69 a of the movable member 67. Therefore, when foreign matter enters the gap 75, abnormal friction or clogging (locking) occurs between the movable member 67 and the inner periphery of the hole 69a. In the worst case, the movable member 67 is located on the inner periphery of the hole 69a. There is a risk of sticking. That is, there is a possibility that the ABV 91 may malfunction due to foreign matter.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to suitably remove the exhaust gas recirculation gas remaining in the pressure equilibrium chamber of the intake bypass valve. An object of the present invention is to provide an intake bypass device for a supercharged engine that can prevent malfunction due to foreign matter.

  In order to achieve the above object, an invention according to claim 1 is provided between an intake passage and an exhaust passage of an engine, and a supercharger for boosting intake air in the intake passage, and a supercharger, A compressor disposed in the intake passage, a turbine disposed in the exhaust passage, a rotating shaft that connects the compressor and the turbine so as to be integrally rotatable, and an exhaust gas discharged from the combustion chamber of the engine to the exhaust passage. The exhaust recirculation passage that flows into the intake passage as the exhaust recirculation gas and recirculates to the combustion chamber, and the exhaust recirculation passage are connected to the exhaust passage downstream of the turbine and the outlet connected to the intake passage upstream of the compressor An exhaust gas recirculation valve for adjusting the flow of exhaust gas recirculation gas in the exhaust gas recirculation passage, an intake air passage downstream of the compressor, and an intake air passage upstream of the compressor An intake bypass passage for bypassing the intake passage, an intake bypass valve for opening and closing the intake bypass passage, an intake bypass valve, a housing, a passage provided in the housing and communicating with the intake bypass passage, and a passage A valve member, a valve member that opens and closes the valve seat, a movable member that moves the valve member relative to the valve seat, an elastic member that urges the valve member together with the movable member in the closing direction, and an elastic member A driving member that drives the valve member in the opening direction opposite to the closing direction together with the movable member against the urging force of the actuator, and is provided between the housing and the valve member, and is connected to the flow path via the pressure responsive member. An intake bypass device for an engine with a supercharger, comprising: a partitioned pressure balance chamber; and a pressure introduction path provided in the valve member and the movable member and communicating the flow path to the pressure balance chamber. Valve pressure A residual gas removal passage for removing exhaust gas recirculation gas that flows into the balance chamber is removed, and a gas outlet that communicates with the pressure equilibrium chamber is provided in the housing, and one end of the residual gas removal passage is connected to the gas outlet. The purpose is that.

  According to the configuration of the above invention, when a negative pressure acts on the residual gas removal passage, the negative pressure acts on the pressure equilibrium chamber of the intake bypass valve via the residual gas removal passage and the gas outlet, and the pressure balance chamber The exhaust gas recirculation gas remaining in the gas is sucked and removed from the pressure equilibrium chamber through the gas outlet and the residual gas removal passage. At this time, the residual exhaust gas to be removed flows from the gas outlet to the residual gas removal passage without flowing inside the driving member.

  In order to achieve the above object, the invention according to claim 2 is the invention according to claim 1, wherein the movable member is provided with a magnetic material, the drive member is an electromagnet, and a hole is provided at the center thereof. The purpose is that the movable member is loosely fitted into the hole via the gap, the housing is provided with a vent hole for communicating the hole and the outside, and the sealing member for sealing the gap is provided.

  According to the configuration of the invention, in addition to the action of the invention according to claim 1, when the electromagnet is excited, the magnetic material is attracted to the electromagnet together with the movable member in the hole, and resists the biasing force of the elastic member. Then, the valve member moves in the opening direction. Here, since the gap between the movable member and the electromagnet is sealed by the sealing member, the exhaust gas recirculation gas remaining in the pressure equilibrium chamber does not flow into the gap.

  To achieve the above object, according to a third aspect of the present invention, in the first aspect of the present invention, the magnetic member is provided at the end of the movable member, the drive member is an electromagnet, and the entire electromagnet is a housing. The movable member is disposed away from the wall of the housing that covers the electromagnet in the pressure equilibrium chamber, and the magnetic material is provided together with the movable member so as to be attracted by the electromagnet.

  According to the configuration of the invention, in addition to the action of the invention according to claim 1, when the electromagnet is excited, the magnetic material is attracted to the electromagnet together with the movable member, and the valve member resists the biasing force of the elastic member. Moves in the opening direction. Here, since the entire electromagnet is covered with the housing, the exhaust gas recirculation gas does not enter the electromagnet. In addition, since the movable member is arranged away from the wall portion covering the electromagnet in the pressure equilibrium chamber, there is no sliding portion between the movable member and the electromagnet, and foreign matter in the exhaust gas recirculation gas remaining in the pressure equilibrium chamber is not present. , It does not enter between the movable member and the electromagnet.

  In order to achieve the above object, according to a fourth aspect of the present invention, in the third aspect of the present invention, the magnetic material has a substantially conical shape and is matched with the shape of the magnetic material on the wall facing the magnetic material. It is intended that a recess having a shape and accepting a magnetic material is formed.

  According to the configuration of the invention described above, in addition to the action of the invention according to claim 3, the magnetic material has a substantially conical shape, the wall facing the magnetic material has a shape matching the shape of the magnetic material, and magnetic Since the recess capable of receiving the material is formed, the surface area of the magnetic material is increased, and the moving stroke of the magnetic material relative to the wall can be set large.

  In order to achieve the above object, the invention according to claim 5 is the invention according to claim 3 or 4, wherein an impact absorbing material is provided on an end surface of the magnetic material or a wall portion facing the end surface of the magnetic material. The purpose is that.

  According to the configuration of the above invention, in addition to the action of the invention according to claim 3 or 4, the impact absorbing material relaxes the impact when the end surface of the magnetic material collides with the wall portion facing the end surface of the magnetic material. .

  To achieve the above object, according to a sixth aspect of the present invention, in the third aspect of the present invention, one of the end face of the magnetic material and the wall portion facing the end face of the magnetic material is flat and the other is inclined. The purpose is to be formed on the surface.

  According to the configuration of the invention described above, in addition to the action of the invention according to claim 3, when the end surface of the magnetic material collides with the wall portion facing the end surface of the magnetic material, the end surface does not hit at once, and the wall gradually It will touch the surface of the part.

  In order to achieve the above object, according to a seventh aspect of the present invention, in the first aspect of the present invention, an intake air amount adjusting valve for adjusting an intake air amount is provided in the intake passage, The purpose is that the other end of the gas removal passage is connected to the intake passage downstream of the intake air amount adjustment valve.

  According to the configuration of the above invention, in addition to the operation of the invention according to any one of claims 1 to 6, the opening amount of the intake air amount adjustment valve is reduced during operation of the engine, and the intake passage downstream of the intake air amount adjustment valve is placed. When the negative pressure is generated, the negative pressure acts on the pressure equilibrium chamber via the residual gas removal passage and the gas outlet, and the exhaust gas recirculation gas is sucked from the pressure equilibrium chamber by the negative pressure.

  In order to achieve the above object, the invention according to claim 8 is the invention according to any one of claims 1 to 7, wherein a check valve is provided in the residual gas removal passage, and the check valve is pressure balanced. The purpose is to allow a gas flow from the chamber to the residual gas removal passage and to prevent a gas flow from the residual gas removal passage to the pressure equilibrium chamber.

  According to the configuration of the above invention, in addition to the operation of the invention according to any one of claims 1 to 7, the flow of gas from the pressure equilibrium chamber to the residual gas removal passage is permitted by the check valve, and the residual gas removal passage The reverse flow of gas from the pressure balance chamber to the pressure equilibrium chamber is blocked by the check valve.

  According to the first aspect of the present invention, the exhaust gas recirculation gas remaining in the pressure equilibrium chamber of the intake bypass valve can be suitably removed, and at the same time, malfunction due to foreign matter in the intake bypass valve can be prevented. .

  According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, abnormal friction and clogging due to foreign matters are surely prevented at the sliding portion between the movable member and the inner periphery of the hole. be able to.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1, abnormal friction and clogging due to foreign matters are reliably prevented at the sliding portion between the movable member and the inner periphery of the hole. be able to.

  According to the invention described in claim 4, in addition to the effect of the invention described in claim 3, the attractive force of the magnetic material by the electromagnet can be increased, and the maximum opening of the valve member can be increased.

  According to the invention described in claim 5, in addition to the effect of the invention described in claim 3 or 4, it is possible to reduce the sound of hitting the valve member when the valve is opened.

  According to the invention described in claim 6, in addition to the effect of the invention described in claim 3, it is possible to reduce the hitting sound when the valve member is opened.

  According to the invention described in claim 7, in addition to the effect of the invention described in any one of claims 1 to 6, exhaust gas recirculation gas remaining from the pressure equilibrium chamber can be removed using the operation of the engine. .

  According to the invention described in claim 8, in addition to the effect of the invention described in any one of claims 1 to 7, the pressure equilibrium chamber can be protected from the action of excessive pressure when the engine is supercharged. .

The schematic block diagram which shows the gasoline engine system with a supercharger which concerns on 1st Embodiment and contains a low pressure loop type EGR apparatus. Sectional drawing which concerns on 1st Embodiment and shows schematic structure of ABV. Sectional drawing which concerns on 2nd Embodiment and shows schematic structure of ABV. Sectional drawing which concerns on 3rd Embodiment and shows schematic structure of ABV. Sectional drawing which concerns on 4th Embodiment and expands and shows the part of the magnetic metal plate and wall part which were provided in the movable member. Sectional drawing which expands and shows the part of the magnetic metal plate and wall part which were provided in the movable member according to 5th Embodiment. Sectional drawing which concerns on 6th Embodiment and shows schematic structure of ABV. Sectional drawing which concerns on a prior art example and shows schematic structure of ABV. Sectional drawing which concerns on a prior art example and shows schematic structure of ABV.

<First Embodiment>
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment that embodies an intake bypass device for a supercharged engine according to the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing a supercharged gasoline engine system including a low-pressure loop exhaust gas recirculation device (low-pressure loop EGR device) in this embodiment. This engine system includes a reciprocating engine 1. An intake passage 3 is connected to the intake port 2 of the engine 1, and an exhaust passage 5 is connected to the exhaust port 4. An air cleaner 6 is provided at the inlet of the intake passage 3. A supercharger 7 for boosting the intake air in the intake passage 3 is provided in the intake passage 3 downstream of the air cleaner 6 between the exhaust passage 5 and the intake passage 3.

  The supercharger 7 includes a compressor 8 disposed in the intake passage 3, a turbine 9 disposed in the exhaust passage 5, and a rotating shaft 10 that connects the compressor 8 and the turbine 9 so as to be integrally rotatable. The supercharger 7 rotates the turbine 9 by the exhaust gas flowing through the exhaust passage 5 and integrally rotates the compressor 8 via the rotary shaft 10 to boost the intake air in the intake passage 3, that is, perform supercharging. It is like that.

  An exhaust bypass passage 11 that bypasses the turbine 9 is provided in the exhaust passage 5 adjacent to the supercharger 7. A waste gate valve 12 is provided in the exhaust bypass passage 11. By adjusting the exhaust gas flowing through the exhaust bypass passage 11 by the waste gate valve 12, the exhaust gas flow rate supplied to the turbine 9 is adjusted, the rotational speeds of the turbine 9 and the compressor 8 are adjusted, and supercharging by the supercharger 7 is performed. The pressure is adjusted.

  In the intake passage 3, an intercooler 13 is provided between the compressor 8 and the engine 1. The intercooler 13 cools intake air that has been pressurized by the compressor 8 to a high temperature to an appropriate temperature. A surge tank 3 a is provided in the intake passage 3 between the intercooler 13 and the engine 1. An electronic throttle device 14 which is an electric throttle valve is provided in the intake passage 3 downstream from the intercooler 13 and upstream from the surge tank 3a. The electronic throttle device 14 detects a butterfly throttle valve 21 disposed in the intake passage 3, a DC motor 22 for opening and closing the throttle valve 21, and an opening degree (throttle opening degree) TA of the throttle valve 21. And a throttle sensor 23 for performing the operation. The electronic throttle device 14 is configured such that the opening degree of the throttle valve 21 is adjusted by the throttle valve 21 being opened and closed by the DC motor 22 in accordance with the operation of the accelerator pedal 26 by the driver. In this embodiment, the electronic throttle device 14 corresponds to an example of an intake air amount adjustment valve of the present invention. The exhaust passage 5 downstream from the turbine 9 is provided with a catalytic converter 15 as an exhaust catalyst for purifying exhaust.

  The engine 1 is provided with an injector 25 for injecting and supplying fuel to the combustion chamber 16. Fuel is supplied to the injector 25 from a fuel tank (not shown). The engine 1 is provided with a spark plug 29 corresponding to each cylinder. Each spark plug 29 is ignited by receiving a high voltage output from the igniter 30. The ignition timing of each spark plug 29 is determined by the high voltage output timing from the igniter 30. The spark plug 29 and the igniter 30 constitute an ignition device.

  In this embodiment, the engine 1 is provided with a low-pressure loop EGR device. The EGR device includes an exhaust gas recirculation passage (EGR passage) 17 for flowing a part of the exhaust gas discharged from the combustion chamber 16 of the engine 1 into the exhaust passage 5 as EGR gas to the intake passage 3 and returning it to the combustion chamber 16; An exhaust gas recirculation valve (EGR valve) 18 for adjusting the flow of EGR gas in the passage 17 is provided. In this embodiment, the EGR passage 17 is provided between the exhaust passage 5 downstream from the catalytic converter 15 and the intake passage 3 upstream from the compressor 8. That is, the EGR passage 17 has an inlet 17 b connected to the exhaust passage 5 downstream from the turbine 9 and the catalytic converter 15, and an outlet 17 a connected to the intake passage 3 upstream from the compressor 8. The EGR passage 17 is provided with an EGR cooler 20 for cooling the EGR gas flowing through the passage 17. In this embodiment, the EGR valve 18 is disposed in the EGR passage 17 downstream of the EGR cooler 20.

As shown in FIG. 1, the EGR valve 18 is configured as a poppet valve and as an electric valve. That is, the EGR valve 18 includes a valve body 32 that is driven by the motor 31. The valve body 32 has a substantially conical shape, and is provided so as to be seated on a valve seat 33 provided in the EGR passage 17. The motor 31 includes an output shaft 34 configured to be capable of reciprocating (stroke) in a straight line, and a valve body 32 is fixed to the tip of the output shaft 34. The output shaft 34 is supported by a housing constituting the EGR passage 17 via a bearing 35. The opening degree of the valve body 32 with respect to the valve seat 33 is adjusted by moving the output shaft 34 of the motor 31 with a stroke. The output shaft 34 of the EGR valve 18 is provided so as to be able to perform a stroke movement by a predetermined stroke from a fully closed state in which the valve body 32 is seated on the valve seat 33 to a fully open state in which the valve body 32 contacts the bearing 35. In this embodiment, in order to realize a large amount of EGR, the opening area of the valve seat 33 is enlarged as compared with the conventional technique. Accordingly, the valve body 32 is enlarged.

  According to the low-pressure loop EGR device described above, negative pressure is generated in the intake passage 3 upstream of the compressor 8 when the engine 1 is in operation and the supercharger 7 operates. At this time, when the EGR valve 18 is opened, a part of the exhaust discharged from the combustion chamber 16 to the exhaust passage 5 flows as EGR gas to the intake passage 3 upstream of the compressor 8 via the EGR passage 17. 8 and the intake passage 3 further flow back to the combustion chamber 16.

  Adjacent to the supercharger 7, the intake passage 3 is provided with an intake bypass passage 41 that bypasses a portion upstream from the compressor 8 and a portion downstream from the compressor 8. The intake bypass passage 41 is provided with an intake bypass valve (hereinafter referred to as “ABV”) 42 for opening and closing the passage 41. By adjusting the amount of intake air flowing through the intake air bypass passage 41 by the ABV 42, the pressure difference between the inlet and the outlet of the compressor 8 is reduced, and surging is prevented. One end 43 a of a residual gas removal passage 43 communicating with the inside of the ABV 42 is connected to the ABV 42 in order to discharge (remove) the EGR gas remaining inside the ABV 42. The other end 43b of the residual gas removal passage 43 is connected to and communicates with the intake passage 3 downstream of the electronic throttle device 14 (throttle valve 21). The residual gas removal passage 43 is provided with a check valve 44 for preventing the back flow of gas.

  In this embodiment, in order to execute fuel injection control, ignition timing control, intake air amount control, EGR control, supercharging control, and the like according to the operating state of the engine 1, the injector 25, the igniter 30, and the electronic throttle device 14 are controlled. The DC motor 22, the motor 31 of the EGR valve 18, and the ABV 42 are controlled by an electronic control unit (ECU) 50 in accordance with the operating state of the engine 1. The ECU 50 stores in advance a central processing unit (CPU), a predetermined control program and the like, various memories for temporarily storing a calculation result of the CPU, and the like, an external input circuit connected to these parts, and an external And an output circuit. An igniter 30, an injector 25, a DC motor 22, a motor 31, and an ABV 42 are connected to the external output circuit. Various sensors 27 and 51 to 55 for detecting the operating state of the engine 1 including the throttle sensor 23 are connected to the external input circuit, and various engine signals are input thereto.

  Here, in addition to the throttle sensor 23, an accelerator sensor 27, an intake pressure sensor 51, a rotation speed sensor 52, a water temperature sensor 53, an air flow meter 54, and an air-fuel ratio sensor 55 are provided as various sensors. The accelerator sensor 27 detects an accelerator opening ACC that is an operation amount of the accelerator pedal 26. The intake pressure sensor 51 detects the intake pressure PM in the surge tank 3a downstream from the throttle valve 21. The rotational speed sensor 52 detects the rotational angle (crank angle) of the crankshaft 1a of the engine 1 and detects the change in the crank angle as the rotational speed (engine rotational speed) NE of the engine 1. The water temperature sensor 53 detects the cooling water temperature THW of the engine 1. The air flow meter 54 is provided in the intake passage 3 immediately downstream of the air cleaner 6 and detects an intake air amount Ga flowing therethrough. The air-fuel ratio sensor 55 is provided in the exhaust passage 5 immediately upstream of the catalytic converter 15, and detects the air-fuel ratio A / F in the exhaust flowing therethrough.

  In this embodiment, the ECU 50 controls the EGR valve 18 in order to execute the EGR control in accordance with the operation state of the engine 1 in the entire operation region of the engine 1. Further, the ECU 50 normally controls the opening of the EGR valve 18 based on the operating state detected during the acceleration operation or the steady operation of the engine 1, and the EGR valve 18 when the engine 1 is stopped, idle operation, or deceleration operation. Is controlled to be fully closed.

  In this embodiment, the ECU 50 controls the electronic throttle device 14 based on the accelerator opening ACC in order to drive the engine 1 in response to a driver's request. Further, the ECU 50 controls to open the electronic throttle device 14 based on the accelerator opening ACC during acceleration operation or steady operation of the engine 1 and closes the electronic throttle device 14 when the engine 1 is stopped or decelerated. It has become. Thereby, the throttle valve 21 is opened during the acceleration operation or the steady operation of the engine 1 and is fully closed when the engine 1 is stopped or decelerated.

  Next, the configuration of the ABV 42 will be described in detail. FIG. 2 is a cross-sectional view showing a schematic configuration of the ABV 42 in this embodiment. The ABV 42 shown in FIG. 2 has the same basic configuration as the ABV 91 shown in FIG. 9. Therefore, the same components are denoted by the same reference numerals, and the description thereof is omitted. The configuration different from FIG. 9 is mainly described. To do. As shown in FIG. 2, the pressure balancing chamber 71 is provided with a rubber bellows 78 corresponding to an example of the sealing member of the present invention that seals the gap 75 between the housing 62 and the movable member 67. The housing 62 can be formed of resin. The housing 62 is provided with a fine ventilation hole 81 that allows the hole 69a to communicate with the outside. The housing 62 is provided with a gas outlet 79 communicating with the pressure equilibrium chamber 71, and one end 43 a of the residual gas removal passage 43 is connected to the gas outlet 79. The other end 43b of the residual gas removal passage 43 is connected to the intake passage 3 downstream of the electronic throttle device 14 (throttle valve 21) (see FIG. 1). The residual gas removal passage 43 is provided with a check valve 44. The check valve 44 allows a gas flow from the pressure balance chamber 71 to the residual gas removal passage 43 and prevents a gas flow from the residual gas removal passage 43 to the pressure balance chamber 71.

  Next, the operation of the ABV 42 will be described. When the electromagnet 69 is not energized (non-excited), the movable member 67 and the valve member 66 are urged in the closing direction in which the valve seat 65 is seated by the urging force of the spring 68. Thereby, ABV42 will be in a valve closing state. On the other hand, when the electromagnet 69 is energized (excited), the valve member 66 is driven in the opening direction together with the movable member 67 against the biasing force of the spring 68 by the electromagnetic force. Thereby, ABV42 will be in a valve opening state.

  In the valve closed state of the ABV 42, the diaphragm 70 defines the pressure equilibrium chamber 71 corresponding to the outflow path 64. The inflow path 63 and the pressure equilibrium chamber 71 act on the pressure equilibrium chamber 71 via the vent hole 73 a of the shielding plate 73 and the pressure introduction path 72. For this reason, the pressure of the intake air applied before and after the valve member 66, that is, the inflow path 63 side and the pressure equilibrium chamber 71 side is balanced. Thereby, the urging force of the spring 68 and the electromagnetic force of the electromagnet 69 are reduced.

  By the way, when the ABV 42 is opened, particularly when the valve opening is started, most of the high-pressure air flowing out from the inflow path 63 to the outflow path 64 through the hollow portion of the valve seat 65 collides with the shielding plate 73. At the same time, most of the air flows to the outflow passage 64, but a part of the air flows into the pressure equilibrium chamber 71 through the pressure introduction passage 72 from the vent 73 a of the shielding plate 73. At this time, the dynamic pressure of the air acting on the pressure equilibrium chamber 71 through the vent hole 73a of the shielding plate 73 is such that the air acting on the pressure equilibrium chamber 71 through the pressure introduction path 72 of the movable member 67 when the shielding plate 73 is omitted. Lower than the dynamic pressure. Accordingly, the dynamic pressure of air acting on the pressure balance chamber 71 at the start of valve opening is reduced. Thereby, compared with a prior art example, the valve opening time required from the start to the end of the valve opening is shortened. In this embodiment, the internal space of the valve member 66 has a passage cross-sectional area larger than the opening area (passage area) of the pressure introduction passage 72 of the movable member 67 and the vent hole 73a of the shielding plate 73. It functions as a buffer chamber for the dynamic pressure of air acting on the equilibrium chamber 71. The buffer chamber corresponds to an inlet side passage of the pressure introduction path 72.

  According to the intake bypass device for an engine with a supercharger of this embodiment described above, the movable member 67 is attracted to the electromagnet 69 in the hole 69a when the electromagnet 69 is excited, and the biasing force of the spring 68 is applied. Accordingly, the valve member 66 moves in the opening direction, and the ABV 42 is opened. Here, the housing 62 of the ABV 42 is provided with a gas outlet 79 communicating with the pressure equilibrium chamber 71, one end 43a of the residual gas removal passage 43 is connected to the gas outlet 79, and the other end 43b of the passage 43 is the throttle. It is connected to the intake passage 3 downstream from the valve 21. Therefore, when negative pressure is generated in the intake passage 3 downstream of the throttle valve 21 during operation of the engine 1, the negative pressure is transferred to the pressure of the ABV 42 via the residual gas removal passage 43, the check valve 44 and the gas outlet 79. It acts on the equilibrium chamber 71. Then, the EGR gas remaining in the pressure equilibrium chamber 71 is sucked by the negative pressure, and the intake passage downstream of the throttle valve 21 from the pressure equilibrium chamber 71 via the gas outlet 79, the check valve 44 and the residual gas removal passage 43. 3 is removed. For this reason, EGR gas remaining in the pressure equilibrium chamber 71 of the ABV 42 can be suitably removed, and generation of condensed water by the residual EGR gas in the pressure equilibrium chamber 71 can be prevented. In addition, in this embodiment, the residual EGR gas to be removed flows from the gas outlet 79 to the residual gas removal passage 43 without flowing into the hole 69a of the electromagnet 69. In particular, in this embodiment, since the gap 75 between the movable member 67 and the electromagnet 69 is sealed by the bellows 78, the EGR gas remaining in the pressure equilibrium chamber 71 does not flow into the gap 75. For this reason, it is possible to reliably prevent abnormal friction and clogging (locking) due to foreign matters such as fine carbon particles at the sliding portion between the movable member 67 and the inner periphery of the hole 69a. As a result, it is possible to prevent malfunction due to foreign matter of the ABV 42.

  In this embodiment, the check valve 44 allows the gas flow from the pressure equilibrium chamber 71 to the residual gas removal passage 43, and the check valve 44 allows the gas flow from the residual gas removal passage 43 to the pressure balance chamber 71. Be blocked. For this reason, when the engine 1 is supercharged, the pressure equilibrium chamber 71 can be protected from the action of excessive pressure.

  In this embodiment, when the engine 1 is in operation, the opening of the throttle valve 21 is reduced and a negative pressure is generated in the intake passage 3 downstream of the throttle valve 21, so that the negative pressure is reduced to the residual gas removal passage 43 and the gas extraction. It acts on the pressure equilibrium chamber 71 through the port 79, and the residual EGR gas is sucked from the pressure equilibrium chamber 71 by the negative pressure. For this reason, the residual EGR gas can be removed from the pressure equilibrium chamber 71 using the operation of the engine 1.

Second Embodiment
Next, a second embodiment of the supercharger-equipped engine intake bypass device according to the present invention will be described in detail with reference to the drawings.

  In each embodiment described below, the description of the same components as those in the first embodiment will be omitted, and different points will be mainly described.

  FIG. 3 shows a schematic configuration of the ABV 42 in a sectional view. This embodiment differs from the first embodiment in the configuration of a blocking member that blocks the gap 75 between the movable member 67 and the electromagnet 69. In this embodiment, a lip seal 80 is provided instead of the bellows 78 of FIG. The lip seal 80 is disposed so as to be interposed between the electromagnet 69 and the movable member 67 in the vicinity of the opening of the hole 69 a of the electromagnet 69. Therefore, in the intake bypass device of this embodiment, in the ABV 42, although the lip seal 80 is interposed between the electromagnet 69 and the movable member 67, there is some sliding resistance in the movement of the movable member 67, but the first implementation. The same effect as the form can be obtained.

<Third Embodiment>
Next, a third embodiment of the supercharger-equipped engine intake bypass device according to the present invention will be described in detail with reference to the drawings.

  FIG. 4 shows a schematic configuration of the ABV 42 in a sectional view. This embodiment differs from the first and second embodiments in the configuration of the movable member 67 and the electromagnet 69. That is, as shown in FIG. 4, in this embodiment, a magnetic metal plate 82 is provided at the upper end of the movable member 67 as an example of the magnetic material of the present invention. In addition, the entire electromagnet 69 is covered with the housing 62, and the movable member 67 is disposed in the pressure equilibrium chamber 71 so as to be separated downward from the wall 62 a of the housing 62 covering the electromagnet 69. A magnetic metal plate 82 is provided together with the movable member 67 so as to be attracted by the electromagnet 69. The electromagnet 69 and the pressure equilibrium chamber 71 are partitioned by a wall 62 a of the housing 62. The wall 62a extends horizontally below the electromagnet 69 to form a flat surface. The movable member 67 has a short shape in which the upper portion of the movable member 67 shown in FIGS. 2 and 3 is omitted. A magnetic metal plate 82 having a larger area than the upper end surface of the movable member 67 is fixed to the upper end of the movable member 67. In addition, in place of the spring 68 shown in FIGS. 2 and 3, the valve member 66 is urged in the closing direction together with the magnetic metal plate 82 and the movable member 67 between the valve member 66 and the wall portion 62a. A spring 83 is provided as an example of the elastic member. In this embodiment, the respective surfaces of the magnetic metal plate 82 and the spring 83 are provided with a corrosion resistant coating for preventing corrosion. Further, in this embodiment, the vent hole 81 is omitted from the housing 62.

  Therefore, according to this embodiment, when the electromagnet 69 of the ABV 42 is excited, the magnetic metal plate 82 is attracted to the electromagnet 69 together with the movable member 67, and the valve member 66 opens in the opening direction against the biasing force of the spring 83. Move to. Here, since the entire electromagnet 69 is covered with the housing 62, the EGR gas does not enter the electromagnet 69. In addition, since the movable member 67 is disposed downwardly from the wall portion 62 a covering the electromagnet 69 in the pressure equilibrium chamber 71, there is no sliding portion between the movable member 67 and the electromagnet 69, so Foreign matter such as fine carbon particles in the remaining EGR gas does not enter between the movable member 67 and the electromagnet 69. That is, in this embodiment, the movable member 67 is not incorporated in the hole 69a of the electromagnet 69 and slides as in the first and second embodiments, but the movable member 67 and the electromagnet 69 are separated. In addition, the movement of the movable member 67 is not hindered by foreign substances in the EGR gas. For this reason, it is possible to reliably prevent abnormal friction and clogging (locking) due to foreign matter between the movable member 67 and the electromagnet 69, and it is possible to prevent malfunction of the ABV 42 due to foreign matter. In addition, the operation and effect relating to the removal of the residual EGR gas in the pressure equilibrium chamber 71 is the same as that of the first and second embodiments.

<Fourth embodiment>
Next, a fourth embodiment in which the intake bypass device for a supercharged engine according to the present invention is embodied will be described in detail with reference to the drawings.

  In the configuration of the third embodiment, when the magnetic metal plate 82 is attracted by the electromagnet 69 when the valve member 66 is opened, a hitting sound may occur due to collision with the wall 62a. Therefore, in this embodiment, an impact mitigation structure for reducing the hitting sound is provided. FIG. 5 is an enlarged cross-sectional view of the magnetic metal plate 82 and the wall portion 62a provided on the movable member 67. As shown in FIG. As shown in FIG. 5, an impact absorbing material 84 is fixed to the lower surface of the wall 62 a corresponding to the magnetic metal plate 82. The shock absorber 84 can be formed of, for example, sponge or rubber. The area of the shock absorber 84 is set slightly larger than the area of the magnetic metal plate 82.

  Therefore, according to this embodiment, in addition to the effects of the third embodiment, in the ABV 42, when the valve member 66 is opened, the shock when the magnetic metal plate 82 collides with the wall portion 62a is caused by the shock absorber 84. Alleviated. As a result, the hitting sound when the valve member 66 is opened can be reduced.

<Fifth Embodiment>
Next, a fifth embodiment in which the intake bypass device for a supercharged engine according to the present invention is embodied will be described in detail with reference to the drawings.

  FIG. 6 is an enlarged sectional view of the magnetic metal plate 82 and the wall 62a provided on the movable member 67. As shown in FIG. This embodiment differs from the fourth embodiment in the configuration of the impact relaxation structure. That is, as shown in FIG. 6, a bank-like rib 62b having a circular shape in plan view is formed on the lower surface of the wall 62a, and the lower surface of the rib 62b forms an inclined surface 62c inclined with respect to the horizontal. Further, the upper end surface 82a of the magnetic metal plate 82 provided on the upper surface side of the movable member 67 forms a flat surface extending horizontally.

Therefore, according to this embodiment, in addition to the operational effects of the third embodiment, in the ABV 42, when the magnetic metal plate 82 collides with the rib 62b when the valve member 66 is opened, the upper surface of the magnetic metal plate 82 is the rib. The timing of colliding with 62b is dispersed. That is, the magnetic metal plate 82
When the upper end surface 82a collides with the wall portion 62a, the upper end surface 82a gradually contacts the inclined surface 62c of the rib 62b without hitting at once. As a result, the hitting sound when the valve member 66 is opened can be reduced.

<Sixth Embodiment>
Next, a sixth embodiment in which the intake bypass device for a supercharged engine according to the present invention is embodied will be described in detail with reference to the drawings.

  FIG. 7 is a sectional view showing a schematic configuration of the ABV 42. This embodiment differs from the third to fifth embodiments in the configuration of the movable member 67 and the electromagnet 69. That is, as shown in FIG. 7, in this embodiment, the magnetic metal piece 85 as the magnetic material of the present invention provided at the upper end of the movable member 67 has a substantially conical shape. In addition, a concave portion 86 having a shape matching the shape of the magnetic metal piece 85 and capable of receiving the magnetic metal piece 85 is formed in the wall portion 62 a facing the magnetic metal piece 85.

  Therefore, according to this embodiment, the magnetic metal piece 85 has a substantially conical shape, and the wall 62a facing the magnetic metal piece 85 has a shape that matches the shape of the metal piece 85. Is formed, the surface area of the magnetic metal piece 85 is increased, and the movement stroke of the metal piece 85 relative to the wall 62a can be set large. For this reason, the attractive force of the magnetic metal piece 85 by the electromagnet 69 can be increased, and the maximum opening degree of the valve member 66 can be increased.

  Note that the present invention is not limited to the above-described embodiments, and a part of the configuration can be changed as appropriate without departing from the spirit of the invention.

  (1) In the fourth embodiment, the shock absorber 84 is provided on the wall 62a. However, the shock absorber may be provided not on the wall but on the magnetic metal plate.

  (2) In the fifth embodiment, the rib 62b having the inclined surface 62c is provided on the wall 62a and the upper end surface 82a of the magnetic metal plate 82 is a horizontal flat surface. However, the lower surface of the wall portion is a horizontal flat surface. The upper end surface of the magnetic metal plate can also be formed as an inclined surface.

  The present invention can be used for a gasoline engine and a diesel engine equipped with a supercharger.

1 Engine 3 Intake passage 5 Exhaust passage 7 Supercharger 8 Compressor 9 Turbine 10 Rotating shaft 14 Electronic throttle device 16 Combustion chamber 17 EGR passage (exhaust gas recirculation passage)
17a outlet 17b inlet 18 EGR valve (exhaust gas recirculation valve)
21 Throttle valve 41 Intake bypass passage 42 ABV (Intake bypass valve)
43 Residual gas removal passage 43a One end 43b The other end 44 Check valve 62 Housing 62a Wall portion 62b Rib 62c Inclined surface 63 Inflow passage (flow path)
64 Outflow channel
65 Valve seat 66 Valve member 67 Movable member 68 Spring (elastic member)
69 Electromagnet (drive member)
69a hole 70 diaphragm (pressure responsive member)
71 Pressure equilibration chamber 72 Pressure introduction path 73 Shielding plate 73a Vent hole 75 Crevice 78 Bellows (blocking member)
79 Gas outlet 80 Lip seal (blocking member)
82 Magnetic metal plate (magnetic material)
82a Upper end surface 83 Spring (elastic member)
84 Shock absorber 85 Magnetic metal piece (magnetic material)
86 recess

Claims (8)

A turbocharger provided between an intake passage and an exhaust passage of the engine for boosting intake air in the intake passage;
The supercharger includes a compressor disposed in the intake passage, a turbine disposed in the exhaust passage, and a rotation shaft that connects the compressor and the turbine so as to be integrally rotatable.
An exhaust gas recirculation passage that causes a part of the exhaust gas discharged from the combustion chamber of the engine to flow into the intake passage as exhaust gas recirculation gas and recirculates to the combustion chamber;
The exhaust gas recirculation passage has an inlet connected to the exhaust passage downstream of the turbine and an outlet connected to the intake passage upstream of the compressor;
An exhaust gas recirculation valve for adjusting the flow of exhaust gas recirculation gas in the exhaust gas recirculation passage;
An intake bypass passage that bypasses between the intake passage downstream of the compressor and the intake passage upstream of the compressor;
An intake bypass valve for opening and closing the intake bypass passage;
The intake bypass valve includes a housing, a flow passage provided in the housing and communicating with the intake bypass passage, a valve seat provided in the flow passage, a valve member that opens and closes the valve seat, and the valve member. A movable member that moves relative to the valve seat, an elastic member that biases the valve member together with the movable member in a closing direction, and a movable member that resists the biasing force of the elastic member A pressure member provided between the housing and the valve member, which drives the valve member in an opening direction opposite to the closing direction, and is partitioned with respect to the flow path via a pressure responsive member. An intake bypass device for a supercharged engine comprising: a chamber; and a pressure introduction path provided in the valve member and the movable member and communicating the flow path to the pressure equilibrium chamber.
A residual gas removal passage for removing the exhaust gas recirculation gas flowing into the pressure balance chamber of the intake bypass valve and remaining; and a gas extraction port communicating with the pressure balance chamber is provided in the housing; An intake bypass device for an engine with a supercharger, wherein one end of a passage is connected to the gas outlet.   The movable member is provided with a magnetic material, the drive member is an electromagnet, a hole is provided at the center thereof, the movable member is loosely fitted in the hole through a gap, and the hole and the outside communicate with each other. The intake bypass device for an engine with a supercharger according to claim 1, wherein a ventilation hole is provided, and a sealing member for sealing the gap is provided.   A magnetic material is provided at an end of the movable member, the drive member is an electromagnet, the entire electromagnet is covered by the housing, and the wall of the housing covers the electromagnet in the pressure balancing chamber. 2. The intake bypass device for an engine with a supercharger according to claim 1, wherein the intake member is disposed apart from a portion, and the magnetic material is provided so as to be attracted by the electromagnet together with the movable member.   The magnetic material has a substantially conical shape, and the wall portion facing the magnetic material has a shape that matches the shape of the magnetic material, and a recess capable of receiving the magnetic material is formed. The intake bypass device for an engine with a supercharger according to claim 3.   The intake bypass device for an engine with a supercharger according to claim 3 or 4, wherein an impact absorbing material is provided on an end face of the magnetic material or the wall portion facing the end face of the magnetic material.   4. The intake air of the supercharged engine according to claim 3, wherein one of the end face of the magnetic material and the wall portion facing the end face of the magnetic material is formed as a flat surface and the other as an inclined surface. Bypass device.   An intake air amount adjustment valve for adjusting an intake air amount is provided in the intake passage, and the other end of the residual gas removal passage is connected to the intake passage downstream of the intake air amount adjustment valve. The intake bypass device for a supercharged engine according to any one of 1 to 6.   A check valve is provided in the residual gas removal passage, and the check valve allows a gas flow from the pressure equilibrium chamber to the residual gas removal passage, and from the residual gas removal passage to the pressure balance chamber. The intake air bypass device for an engine with a supercharger according to any one of claims 1 to 7, wherein a gas flow is blocked.

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