JP2020041507A - Evaporated fuel treatment device - Google Patents

Abstract

To provide an evaporated fuel treatment device capable of instantaneously switching a connection state of a passage in comparison with a rotary type valve and not requiring stop of a purge pump during a switching operation of the connection state of the passage.SOLUTION: A valve unit 60 includes: a canister-side valve inflow port 61A; a canister-side valve outflow port 61B; a pump-side valve inflow port 62A; a pump-side valve outflow port 62B; an intake passage-side valve connection port 65A; a first selector valve 63 connected to a side of an outflow port of a purge pump; and a second selector valve 64 connected to a side of an inflow port of the purge pump. The first selector valve has a solenoid valve system, and can switch a connecting destination of the pump-side valve inflow port to the canister-side valve outflow port or the intake passage-side valve connection port, and the second selector valve has a solenoid valve system, and can switch a connecting destination of the pump-side valve outflow port to the canister-side valve inflow port or the intake passage-side valve connection port.SELECTED DRAWING: Figure 3

Description

  The technology disclosed in the present specification relates to an evaporative fuel processing device.

  Conventionally, in an internal combustion engine, evaporated fuel generated in a fuel tank is adsorbed to a canister so as not to be released into the atmosphere. A so-called purge system is used in which a purge gas containing evaporated fuel adsorbed in a canister is guided to an intake passage via a purge passage, and is sucked and burned by an internal combustion engine together with intake air. There is also a purge system in which a purge pump is disposed in a purge passage from a canister to an intake passage, and purge gas from the canister is positively discharged to the intake passage by the purge pump.

  For example, Patent Literature 1 discloses a purge passage that guides a purge gas from a canister that adsorbs fuel vapor to an intake passage, a purge pump disposed in the purge passage, and a rotary type that switches a connection state between the purge passage and the purge pump. A valve unit with a purge air pump having a valve unit is disclosed. The rotary type valve unit has a cylindrical valve, a rotating means for rotating the valve, and various passages whose ends are arranged to face the outer peripheral surface of the valve. The passage includes a passage from the canister, a purge passage to the intake passage, a passage on the suction side of the purge air pump, and a passage on the discharge side of the purge air pump. The valve is formed with a plurality of switching paths that allow the path to be switched to various paths, and is configured to switch the connection state of the path including the purge air pump according to the rotation angle of the valve.

US Patent Application Publication No. 2017/0184057

  The valve unit provided with the purge air pump described in Patent Document 1 switches the connection state of the passage by rotating a rotary valve, so that it takes time to switch. Further, for example, when switching from the first connection state to the third connection state, when there is a second connection state that is not desired by this switching during the rotation of the valve, it is necessary to stop the purge air pump. There are cases. When it is necessary to stop the purge air pump, it takes time until the purge air pump actually stops, so that the time required to switch the connection state may be longer.

  In order to solve the above problems, a technical problem disclosed in the present specification is to provide an evaporative fuel processing apparatus having a canister, a purge passage, a purge pump, and a valve unit, in which the passage is connected as compared with a rotary valve. It is an object of the present invention to provide an evaporative fuel treatment apparatus which can switch the state instantaneously and does not need to stop the purge pump during the operation of switching the connection state of the passage.

  In order to solve the above-mentioned problem, the fuel vapor processing apparatus disclosed in the present specification employs the following means.

  The first means includes a canister for adsorbing the fuel vapor, a purge passage for guiding a purge gas containing the fuel vapor adsorbed by the canister to an intake passage of the internal combustion engine, a purge pump for pumping the purge gas, the canister and the canister. In the evaporative fuel processing device having a purge passage and a valve unit for switching a connection state between the purge pump and the purge pump, the valve unit includes a canister-side valve inlet through which the purge gas flows from the canister, and the purge gas flowing into the canister. A canister-side valve outlet through which the purge gas can flow out, a pump-side valve inlet through which the purge gas flows from the purge pump, and a pump-side valve outlet through which the purge gas can flow out to the purge pump. Connected to the intake passage via the purge passage An intake passage side valve connection port, a first switching valve connected to the outlet side of the purge pump via the pump side valve inlet, and the purge pump via the pump side valve outlet. A second switching valve connected to the inlet side of the valve, wherein the first switching valve is a solenoid valve type, and the connection destination of the pump side valve inlet is the canister side valve outlet or The second switching valve is a solenoid valve type, and a connection destination of the pump-side valve outlet is connected to the canister-side valve inlet or the intake port. This is an evaporative fuel processing device that can be switched to one of the passage-side valve connection ports.

  According to the first means, since the first switching valve and the second switching valve are of a solenoid valve type, the connection state of the passage can be instantaneously switched as compared with a rotary valve. In addition, the first switching valve can switch the pump-side valve inlet to either the canister-side valve outlet or the intake passage-side valve connection port, and during the switching, the other connection state may not occur. There is no. Therefore, it is not necessary to stop the purge pump during the switching operation. In addition, the second switching valve can switch the pump-side valve outlet to either the canister-side valve inlet or the intake passage-side valve connection port. There is no. Therefore, it is not necessary to stop the purge pump during the switching operation.

  The second means is the evaporative fuel processing apparatus according to the first means, wherein the canister-side valve outlet and the canister-side valve inlet are arranged substantially in parallel, and the pump-side valve outlet and the pump-side valve outlet are connected to each other. The pump-side valve inlet is disposed substantially in parallel, and the extending direction of the pump-side valve outlet and the pump-side valve inlet is relative to the extending direction of the canister-side valve outlet and the canister-side valve inlet. An evaporative fuel treatment apparatus wherein the pump-side valve outlet and the pump-side valve inlet are arranged so as to be substantially perpendicular.

  According to the second means, the configuration is simplified, the valve unit can be reduced in size, and the cost of the valve unit can be reduced. Further, by disposing the canister corresponding to the canister-side valve inlet of the valve unit and the canister corresponding to the canister-side valve outlet of the valve unit substantially in parallel, the canister and the valve unit can be connected to each other. One touch connection is possible. Further, if the outlet of the purge pump corresponding to the pump-side valve inlet of the valve unit and the inlet of the purge pump corresponding to the pump-side valve outlet of the valve unit are arranged substantially in parallel, the purge pump and the valve The unit can be connected with one touch. Further, by arranging the extending direction of the canister-side valve outlet and the canister-side valve inlet and the extending direction of the pump-side valve outlet and the pump-side valve inlet substantially at a right angle, a valve unit attached to the canister can be provided. And the purge pump attached to the valve unit can be accommodated in a narrower area. Therefore, the canister, the valve unit, and the purge pump can be integrated more compactly, so that, for example, a mounting space to be mounted on a vehicle can be reduced.

  A third means is the evaporative fuel processing apparatus according to the first means or the second means, wherein the yoke of the first switching valve and the yoke of the second switching valve are integrated, It is a fuel processor.

  According to the third means, since the yoke of the first switching valve and the yoke of the second switching valve are integrated, the number of parts and the manufacturing process of the yoke are reduced as compared with the case where the yoke is provided separately. And the number of assembly steps can be reduced, and the valve unit can be made smaller and lighter.

  A fourth means is the evaporative fuel processing apparatus according to any one of the first to third means, wherein a valve body, which is a movable body in the first switching valve, and a plunger are integrated. The valve body and the plunger, which are movable bodies in the second switching valve, are an integrated fuel vapor treatment device.

  According to the fourth means, the valve element of the first switching valve and the plunger are integrated, and the valve element of the second switching valve and the plunger are integrated, so that the valve element and the plunger are formed as separate bodies. The number of parts, the number of manufacturing steps, and the number of assembling steps can be reduced as compared with those of the first embodiment. Further, heat generated in the coil of the first switching valve can be radiated by the valve body (the valve body in contact with the flowing purge gas) via the plunger, which is more preferable. Similarly, the heat generated in the coil of the second switching valve can be dissipated by the valve body (the valve body in contact with the flowing purge gas) via the plunger, which is more preferable.

  A fifth means is the evaporative fuel treatment device according to any one of the first means to the fourth means, wherein the first switching valve is connected to the pump-side valve inflow port in a non-energized state. An evaporative fuel treatment device connected to the canister-side valve outlet, and wherein the second switching valve connects the pump-side valve outlet to the canister-side valve inlet in a non-energized state.

  According to the fifth aspect, when both the first switching valve and the second switching valve are in a non-energized state, the purge gas from the canister flows from the canister-side valve inlet to the pump-side valve outlet and further to the purge pump. And is guided from the pump-side valve inlet to the canister-side valve outlet and returned to the canister (that is, the operation in the circulation mode). The operation modes of the evaporative fuel processing apparatus include a purge mode in which the purge gas from the canister is introduced into the intake passage of the internal combustion engine, a circulation mode in which the purge gas from the canister is returned to the canister via the purge pump, and an operation mode in the intake passage of the internal combustion engine. And a reverse flow mode for guiding the gas to the canister. Of these three modes, the mode that is used most frequently is the circulation mode. In this circulation mode, the first switching valve and the second switching valve are in the non-energized state, so that the power consumption is further reduced. can do.

  The sixth means is the fuel vapor processing apparatus according to any one of the first means to the fifth means, wherein a moving direction of the movable body of the first switching valve and a moving direction of the second switching valve are determined. The moving direction of the movable body is substantially parallel, and the moving direction is substantially horizontal when the evaporated fuel processing device is mounted on a vehicle.

  In the vehicle, the vibration level in the horizontal direction is very small compared to the vibration level in the vertical direction. Therefore, according to the sixth means, the occurrence of erroneous operation of the first switching valve and the second switching valve is further suppressed. be able to.

  The evaporative fuel treatment apparatus disclosed in the present specification adopts the above-described means to connect the passage in the evaporative fuel treatment apparatus having the canister, the purge passage, the purge pump, and the valve unit as compared with the rotary valve. The state can be switched instantaneously, and there is no need to stop the purge pump during the operation of switching the connection state of the passage.

FIG. 2 is a diagram illustrating an example of an engine control system including an evaporated fuel processing device. FIG. 3 is a perspective view illustrating an example of the appearance and connection of a canister, a purge passage, a purge pump, and a valve unit that constitute the evaporated fuel processing device. It is sectional drawing explaining the structure of a valve unit. It is a perspective view explaining the example of an external appearance of an integrated yoke, an integrated valve element and a plunger. FIG. 4 is a diagram illustrating states of a first switching valve and a second switching valve and a flow of purge gas in a purge mode. It is a figure explaining the state of the 1st switching valve and the 2nd switching valve in the circulation mode, and the flow of purge gas. FIG. 5 is a diagram illustrating states of a first switching valve and a second switching valve and a flow of a purge gas in a reverse flow mode. FIG. 4 is a perspective view illustrating an example in which the fuel vapor treatment device is mounted on a vehicle such that the plunger moves in a horizontal direction.

  Hereinafter, embodiments will be described with reference to the drawings.

● [Overall configuration of internal combustion engine control system 1 including evaporative fuel processing device 100 (FIG. 1)]
Hereinafter, embodiments for implementing the technology disclosed herein will be described with reference to the drawings. FIG. 1 shows an example of the overall configuration of an internal combustion engine control system 1 (including an evaporated fuel processing device 100) mounted on a vehicle. In the description of the present embodiment, a gasoline engine will be described as an example of an internal combustion engine.

  As shown in FIG. 1, the internal combustion engine control system 1 is controlled by a control device 40, and from an intake side to an exhaust side, an air cleaner 10, an intake passage 21, a throttle 13, an intake passage 22, an intake passage 24 (surge tank), an intake manifold 25, a combustion chamber 26, an exhaust manifold 27, an exhaust passage 28, a catalyst 29P, an exhaust passage 29, a muffler 15, and the like are arranged in this order. The control device 40 is, for example, an engine control unit including a CPU. A purge passage 65 from the evaporated fuel processing device 100 is connected to the intake passage 22 on the downstream side of the throttle 13. In addition, the purge passage 65 may be connected to the intake passage 21 on the upstream side of the throttle 13. In the present embodiment, an example in which the purge passage 65 is connected to the intake passage 22 on the downstream side of the throttle 13 will be described. .

  The air cleaner 10 is a device that removes foreign substances such as dust contained in the intake air, and includes an intake air amount detection unit 10S (for example, an air flow sensor) for detecting an intake air amount (flow rate), and an intake air. There is provided an intake air temperature detecting means 10T (for example, an intake air temperature sensor) for detecting the temperature of the intake air. Then, the intake air amount detecting means 10S outputs a detection signal to the control device 40, and the intake air temperature detecting means 10T outputs a detection signal to the control device 40.

  The throttle 13 is provided with a throttle valve that can change the opening area of the intake passage by controlling the rotation angle. The rotation angle of the throttle valve is determined based on an accelerator depression amount based on a detection signal from an accelerator depression amount detecting means (not shown) for detecting a depression amount of an accelerator pedal from a user, and various operating states of the internal combustion engine. Thus, it is controlled by the control device 40. The rotation angle of the throttle valve is detected by a rotation angle detecting means 13S (for example, a throttle angle sensor). Then, the rotation angle detecting means 13S outputs a detection signal to the control device 40.

  The fuel vapor processing apparatus 100 includes a canister 50, a valve unit 60, a purge pump 70, a purge passage 65, and the like, and is connected to the intake passage 22 via the purge passage 65. The canister 50 is connected to the fuel tank 30 via an evaporative fuel introduction passage 53, and the evaporative fuel generated in the fuel tank 30 is adsorbed on the activated carbon in the canister 50 via the evaporative fuel introduction passage 53. An air introduction passage 54 is connected to the canister 50. The air introduction passage 54 allows the air to flow into the canister 50 and prohibits the fuel vapor from flowing out of the canister 50 to the atmosphere. A check valve 82 is provided. The backflow prevention valve 82 is an electromagnetic valve that can open or close the air introduction passage 54 and is opened when the power is not supplied, and is controlled by the control device 40.

  The canister 50 and the valve unit 60 are connected by a first canister passage 51 and a second canister passage 52, and the purge pump 70 and the valve unit 60 are connected by a first pump passage 71 and a second pump passage 72. Have been. Further, the valve unit 60 is provided with a pressure detecting means 68, and the pressure detecting means 68 (for example, a pressure sensor) sends a detection signal corresponding to the pressure of the purge gas in a predetermined passage in the valve unit 60 to the control device 40. Output to One end of a purge passage 65 is connected to the valve unit 60, and the other end of the purge passage 65 is connected to the intake passage 22. A purge valve 81 is provided in the purge passage 65. The purge valve 81 is an electromagnetic valve capable of adjusting the opening degree of the purge passage 65, and the control device 40 can control the purge valve 81 to an arbitrary opening degree (including fully closed and fully opened). For example, when performing the above-described purge control, the control device 40 outputs a control signal to the purge valve 81 such that the valve opening degree obtained in accordance with the operation state of the internal combustion engine is obtained. The details of the configuration and the like of the evaporated fuel processing device 100 will be described later.

  The intake passage 24 is a surge tank, and the intake passage 24 is provided with pressure detecting means 24S (for example, a pressure sensor) capable of detecting the pressure in the intake passage 24 (the pressure of the intake passages 22, 24 and the intake manifold 25). ing. Then, the pressure detection unit 24S outputs a detection signal corresponding to the detected pressure to the control device 40.

  The intake manifold 25 is provided with an injector 25A for injecting fuel. Then, liquid fuel from the fuel tank 30 is supplied to the injector 25A, and the injector 25A controls the valve opening time based on a control signal from the control device 40, and directs the atomized fuel to the combustion chamber 26. To inject. The description of the intake valve 25V, the exhaust valve 27V, and the piston 26P is omitted. Further, the injector 25A may be provided at a position where fuel is directly injected into the combustion chamber 26.

  The combustion chamber 26 is provided with an ignition plug 26A. Then, the spark plug 26A generates a spark in the combustion chamber 26 based on a control signal from the control device 40 to burn and explode the compressed air-fuel mixture in the combustion chamber 26.

  In the engine E including the combustion chamber 26, a crank rotation detecting means 26N (for example, a rotation detecting sensor) for detecting the rotation of the crankshaft 26C, and a water temperature detecting means 26W (for example, a water temperature sensor) for detecting the temperature of the coolant for cooling the engine E And a cylinder detecting means 26G (for example, a rotation detection sensor) for detecting a predetermined rotation angle of a predetermined cylinder based on the rotation of a camshaft or the like of the engine E. Each of the crank rotation detecting means 26N, the cylinder detecting means 26G, and the water temperature detecting means 26W outputs a detection signal to the control device 40.

  The exhaust manifold 27 is provided with air-fuel ratio detection means 27S (for example, an A / F sensor) for detecting an air-fuel ratio from exhaust gas after combustion and explosion in the combustion chamber 26. The air-fuel ratio detection means 27S outputs a detection signal corresponding to the detected air-fuel ratio to the control device 40.

  The catalyst 29P is a so-called three-way catalyst, and when the air-fuel ratio detected by the air-fuel ratio detection means 27S is within a predetermined range with respect to the stoichiometric air-fuel ratio (λ = 1.0), the catalyst 29P is harmful. Purifies substances most efficiently.

Downstream of the catalyst 29P, an O ₂ detecting means 29S (for example, an O ₂ sensor) is provided. The O ₂ detection means 29S detects the presence or absence of oxygen contained in the exhaust gas that has passed through the catalyst 29P, and outputs a detection signal to the control device 40. The description of the muffler 15 (so-called muffler) is omitted.

● [Appearance of each component of evaporative fuel treatment device 100 and connection of each component (FIG. 2)]
Next, the appearance of each component constituting the evaporative fuel treatment apparatus 100 and the connection of each component will be described with reference to FIG. As described above, the components of the evaporated fuel processing apparatus 100 include the purge passage 65, the purge pump 70, the valve unit 60, and the canister 50. It should be noted that the thick dotted arrow shown in FIG. 2 indicates the direction in which the purge gas flows.

  The purge passage 65 is a general pipe. As shown in FIG. 2, one end is connected to an intake passage side valve connection port 65A of the valve unit 60, and the other end is connected to the intake passage 22 (see FIG. 1). Have been. The purge passage 65 is provided with a purge valve 81 capable of adjusting the opening degree of the purge passage 65 in accordance with a control signal from the control device 40. The purge passage 65 can guide the purge gas containing the evaporated fuel adsorbed by the canister 50 to the intake passage 22 of the internal combustion engine.

  The purge pump 70 has a pump inlet 71A and a pump outlet 71B, is driven in response to a control signal from the control device 40, and pumps the purge gas flowing from the pump inlet 71A through the pump outlet 71B. I do. The pump inlet 71A is connected to the pump-side valve outlet 62B of the valve unit 60, and the pump outlet 71B is connected to the pump-side valve inlet 62A of the valve unit 60.

  The valve unit 60 has a canister-side valve inlet 61A into which the purge gas flows from the canister 50, and a canister-side valve outlet 61B through which the purge gas can flow out to the canister 50. Further, the valve unit 60 has a pump-side valve inlet 62A into which a purge gas flows from the purge pump 70 and a pump-side valve outlet 62B through which the purge gas can flow out to the purge pump 70. Further, the valve unit 60 has an intake passage side valve connection port 65A connected to the intake passage 22 (see FIG. 1) via the purge passage 65.

  Further, the canister inlet 51A and the canister valve outlet 61B are connected to form the first canister passage 51, and the canister outlet 51B and the canister valve inlet 61A are connected to form the second canister passage 52. I have. The first pump passage 71 is formed by connecting the pump inlet 71A and the pump-side valve outlet 62B, and the second pump passage 72 is formed by connecting the pump outlet 71B and the pump-side valve inlet 62A. I have.

  In addition, the valve unit 60 controls the first switching valve 63 and the second switching valve 64 (see FIG. 3) housed therein by a control signal from the control device 40, so that the connection state of each connection port ( (The connection state of the canister, the purge passage, and the purge pump). The connection state includes three modes, a purge mode, a circulation mode, and a backflow mode, which will be described later. The valve unit 60 is provided with a pressure detecting means 68. The pressure detecting means 68 outputs a detection signal corresponding to the pressure of the purge gas flowing in the canister-side valve outlet 61B to the controller 40, as shown in FIG.

  The canister 50 contains activated carbon for adsorbing the evaporated fuel, and is connected to the evaporated fuel introduction passage 53, the atmosphere introduction passage 54, the canister inlet 51A, and the canister outlet 51B. The evaporative fuel generated in the fuel tank is guided to the canister 50 via the evaporative fuel introduction passage 53, and is adsorbed by the activated carbon in the canister 50. A check valve 82 is provided in the atmosphere introduction passage 54. The connection destinations of the canister inlet 51A and the canister outlet 51B have been described above, and a description thereof will be omitted.

  Further, the pump-side valve inlet 62A and the pump-side valve outlet 62B are arranged substantially in parallel at a predetermined interval, and the pump outlet 71B and the pump inlet 71A are also arranged in substantially parallel at a predetermined interval. I have. Therefore, when the purge pump 70 is connected to the valve unit 60, the pump inlet 71A is externally fitted to the pump-side valve outlet 62B, and the pump-side valve inlet 62A is externally fitted to the pump outlet 71B. It can be easily connected (the description of the sealing material and the like is omitted).

  In addition, the canister-side valve inlet 61A and the canister-side valve outlet 61B are arranged substantially in parallel at a predetermined interval, and the canister outlet 51B and the canister inlet 51A are also arranged in substantially parallel at a predetermined interval. I have. Therefore, when the valve unit 60 is connected to the canister 50, the canister-side valve inlet 61A is fitted to the canister outlet 51B, and the canister inlet 51A is fitted to the canister-side valve outlet 61B. (Description of a sealing material and the like is omitted). Note that the connection destinations of the intake passage-side valve connection port 65A, the pump-side valve inflow port 62A, and the pump-side valve outflow port 62B have been described above, and will not be described.

  Also, the pump-side valve outlet 62B and the pump-side valve inlet 62A extend substantially perpendicularly to the extension direction of the canister-side valve outlet 61B and the canister-side valve inlet 61A, respectively. An outlet 62B and a pump-side valve inlet 62A are arranged. Accordingly, the purge pump 70 is connected to the valve unit 60 in a direction substantially perpendicular to the valve unit 60, and the purge pump 70 is connected to the valve unit 60 in a direction inclined at a predetermined inclination angle. In comparison, the physique of the valve unit 60 to which the purge pump 70 is connected can be made more compact.

  With the above configuration, when assembling the evaporated fuel processing apparatus 100, the valve unit 60 may be connected to the canister 50, the purge pump 70 may be connected to the valve unit 60, and the purge passage 65 may be connected to the valve unit 60. That is, since the general long pipe is only the purge passage 65, the assembly is easy.

● [Internal structure of valve unit 60 (FIGS. 3 and 4)]
Next, the internal structure of the valve unit 60 will be described with reference to FIGS. FIG. 3 is a sectional view of the valve unit 60, and FIG. 4 is an exploded perspective view of the first switching valve 63 and the second switching valve 64. In FIG. 3, for ease of explanation, the pump-side valve inlet 62A shown in FIG. 2 is described on the right side in FIG. 3 instead of near the region R62A in FIG. 3, and is shown in FIG. The pump-side valve outlet 62B is described in the upper right part in FIG. 3 instead of near the region R62B in FIG. In FIG. 3, the passage T2B1 of the pump-side valve outlet 62B communicates with the passage T2B2.

  As shown in FIG. 3, the valve unit 60 includes an intake passage side valve connection port 65A, a canister side valve inflow port 61A, a canister side valve outflow port 61B, and a pump side valve flow as connection ports to be connected to other devices and the like. It has an inlet 62A and a pump-side valve outlet 62B. Further, the valve unit 60 has a first switching valve 63 and a second switching valve 64 for switching a connection state of a passage formed therein. The first switching valve 63 and the second switching valve 64 are, for example, three-way valves.

  The valve unit 60 includes a passage T1A extending from the first switching valve 63 to the intake passage-side valve connection port 65A and a passage T1A extending from the first switching valve 63 to the pump-side valve inlet 62A as passages connected to the first switching valve 63. It has a passage T1B leading to the first switching valve 63 and a passage T1C leading to the canister-side valve outlet 61B. The first switching valve 63 is connected to the outlet of the purge pump 70 via the passage T1B and the pump-side valve inlet 62A.

  Further, the valve unit 60 includes a passage T2A extending from the second switching valve 64 to the intake passage-side valve connection port 65A, and a passage T2A extending from the second switching valve 64 to the pump-side valve outlet 62B. It has passages T2B2 and T2B1 and a passage T2C from the second switching valve 64 to the canister-side valve inlet 61A. The second switching valve 64 is connected to the inlet of the purge pump 70 via the passages T2B2, T2B1 and the pump-side valve outlet 62B.

  A throttle 61BS is formed in the passage T1C from the first switching valve 63 to the canister-side valve outlet 61B, and the pressure between the throttle 61BS and the first switching valve 63 in the passage T1C is equal to the pressure. Detected by the detecting means 68. In the middle of the passage T2A from the second switching valve 64 to the intake passage side valve connection port 65A, a throttle portion 65AS is formed.

  As shown in FIGS. 3 and 4, the first switching valve 63 is a solenoid valve type, and includes a yoke 63Y, a coil 63C, an elastic body 63D, a plunger 63P, a valve body 63V, seal members 63R, 63S, and the like. I have. Similarly, the second switching valve 64 is a solenoid valve type as shown in FIGS. 3 and 4, and includes a yoke 64Y, a coil 64C, an elastic body 64D, a plunger 64P, a valve body 64V, seal members 64R, 64S, and the like. are doing. Since the first switching valve 63 and the second switching valve 64 are of a solenoid valve type, the connection state of the passage can be instantaneously switched as compared with a rotary valve.

  The yoke 63Y of the first switching valve 63 and the yoke 64Y of the second switching valve 64 are integrated. Therefore, the number of parts, the manufacturing process and the assembling process of the yoke can be reduced as compared with the case where the yoke is formed separately, and the valve unit can be made smaller and lighter. Further, the plunger 63P of the first switching valve 63 and the valve body 63V are integrated, and the plunger 64P of the second switching valve 64 and the valve body 64V are integrated. Therefore, the number of parts, the number of manufacturing steps, and the number of assembling steps can be reduced as compared with the case where the valve body and the plunger are formed separately. Further, the heat generated by the coil can be appropriately radiated by the valve body (the valve body in contact with the flowing purge gas) via the plunger.

  As shown in FIG. 3, a seal member 63R as an annular elastic body is provided on the side of the passage T1A in the valve body 63V, and a seal member 63S as an annular elastic body is provided on the side of the passage T1C in the valve body 63V. Is provided. A through hole 63H is formed between the plunger 63P and the valve body 63V. Similarly, a seal member 64R, which is an annular elastic body, is provided on the side of the passage T2A in the valve body 64V, and a seal member 64S, which is an annular elastic body, is provided on the side of the passage T2C in the valve body 64V. . Further, a through hole 64H is formed between the plunger 64P and the valve body 64V.

  As shown in FIG. 3, when the first switching valve 63 is in a non-energized state, the plunger 63P and the valve body 63V are urged toward the passage T1A by the elastic body 63D, and the valve body 63V and the seal member 63R cause the passage T1A to be closed. The opening is closed, and the passage T1B and the passage T1C are communicated by the through hole 63H. Therefore, the first switching valve 63 connects the pump-side valve inlet port 62A to the canister-side valve outlet port 61B when not energized. When the first switching valve 63 is in the energized state, the plunger 63P and the valve body 63V are sucked toward the passage T1C, the opening of the passage T1C is closed by the valve body 63V and the seal member 63S, and the passages T1B and T1A are closed. Is communicated. Therefore, the first switching valve 63 connects the pump-side valve inlet port 62A to the intake-passage-side valve connection port 65A in the energized state. Thus, the first switching valve 63 connects the pump-side valve inlet 62A (passage T1B) to the canister-side valve outlet 61B (passage T1C) or the intake passage-side valve connection port 65A (passage T1A). It can be switched to either one.

  Similarly, as shown in FIG. 3, when the second switching valve 64 is in a non-energized state, the plunger 64P and the valve body 64V are urged toward the passage T2A by the elastic body 64D, and the valve body 64V and the seal member 64R cause the plunger 64P and the valve body 64V to urge. The opening of the passage T2A is closed, and the passage T2B2 (and the passage T2B1) and the passage T2C are communicated by the through hole 64H. Therefore, the second switching valve 64 connects the pump-side valve outlet 62B to the canister-side valve inlet 61A in the non-energized state. When the second switching valve 64 is in the energized state, the plunger 64P and the valve body 64V are sucked toward the passage T2C, the opening of the passage T2C is closed by the valve body 64V and the seal member 64S, and the passage T2B2 (and the passage T2B2). T2B1) and the passage T2A. Therefore, the second switching valve 64 connects the pump-side valve outlet port 62B to the intake passage-side valve connection port 65A when in the energized state. As described above, the second switching valve 64 connects the pump-side valve outlet 62B (the passages T2B1 and T2B2) to the canister-side valve inlet 61A (the passage T2C) or the intake passage-side valve connection port 65A (the passage T2A). Can be switched to any one of

● [Operation mode of evaporative fuel processing apparatus 100 and connection state of passage (FIGS. 5 to 7)]
Next, an operation mode of the evaporated fuel processing apparatus 100 will be described with reference to FIGS. There are three operation modes: a purge mode, a circulation mode, and a backflow mode.

[Purge mode (Fig. 5)]
The purge mode shown in FIG. 5 uses the purge pump 70 when, for example, the operation state is such that the air-fuel ratio of the internal combustion engine is stable, and when it is estimated that a predetermined amount or more of fuel vapor has been adsorbed to the canister 50. This is an operation mode in which a purge gas containing evaporated fuel is discharged from the canister 50 toward the intake passage 22 (see FIG. 1) of the internal combustion engine. In the purge mode, the first switching valve 63 is in the energized state, and the second switching valve 64 is in the non-energized state. In the purge mode, the number of revolutions of the purge pump 70 is changed according to the concentration of the evaporated fuel in the purge gas and the like.

  5 to 7, the black triangle symbol of the first switching valve 63 indicates that the passage is closed (in FIG. 5, the first canister passage 51 and the canister-side valve outlet 61B are closed), The white triangle symbol of the first switching valve 63 indicates that the passage is opened (in FIG. 5, the purge passage 65 and the intake passage side valve connection port 65A are opened). Similarly, in FIGS. 5 to 7, the black triangle symbol of the second switching valve 64 indicates that the passage is closed (in FIG. 5, the purge passage 65 and the intake passage side valve connection port 65A are closed). The white triangular symbol of the second switching valve 64 indicates that the passage is open (in FIG. 5, the second canister passage 52 and the canister-side valve inlet 61A are open).

  In the purge mode, the check valve 82 is controlled by the control device 40 (see FIG. 1) to be in an open state (non-energized state), the atmosphere introduction passage 54 is opened, and the canister 50 can suction the atmosphere. Is in an open state (energized state) with a predetermined opening degree by the control device 40 (see FIG. 1). The purge pump 70 is driven by the control device 40 (see FIG. 1), the first switching valve 63 is energized by the control device 40 (see FIG. 1), and the second switching valve 64 is controlled by the control device 40 (see FIG. 1). (See FIG. 3). Further, the dotted arrows in FIG. 5 indicate the direction in which the purge gas flows.

  The fuel vapor in the canister 50 becomes a purge gas containing the fuel vapor and becomes a purge gas from the second canister passage 52 (canister-side valve inlet 61A) to the second switching valve 64 and the first pump passage 71 (pump-side valve outlet 62B). To the inflow port of the purge pump 70. The purge pump 70 pumps the purge gas from its own outlet, and the purged gas is sent to the purge passage 65 (the intake passage) via the second pump passage 72 (the pump-side valve inlet 62A) and the first switching valve 63. (The side valve connection port 65A) and is discharged into the intake passage 22.

[Circulation mode (Fig. 6)]
The circulation mode shown in FIG. 6 is, for example, an operation mode that is executed when the air-fuel ratio of the internal combustion engine is not stable (transient state or the like) or when the operation of the internal combustion engine is stopped. This is the operation mode. In this circulation mode, the purge pump 70 may or may not be driven. In the circulation mode, the first switching valve 63 and the second switching valve 64 are not energized. In the most frequent circulation mode, the first switching valve 63 and the second switching valve 64 may be set to the non-energized state, so that the power consumption can be further reduced. In the circulation mode, when the purge pump 70 is driven, the purge pump 70 is controlled at a relatively low speed and at a substantially constant speed.

  In the circulation mode, the check valve 82 is controlled to be open (non-energized state) by the control device 40 (see FIG. 1) to open the air introduction passage 54, and the purge valve 81 is controlled by the control device 40 (see FIG. 1). The purge passage 65 is closed by being controlled to a closed state (non-energized state). The first switching valve 63 is de-energized by the control device 40 (see FIG. 1), and the second switching valve 64 is de-energized by the control device 40 (see FIG. 1). In the following, a description will be given in a state where the purge pump 70 is driven by the control device 40. The dotted arrows in FIG. 6 indicate the direction in which the purge gas flows.

  The fuel vapor in the canister 50 becomes a purge gas containing the fuel vapor and becomes a purge gas from the second canister passage 52 (canister-side valve inlet 61A) to the second switching valve 64 and the first pump passage 71 (pump-side valve outlet 62B). To the inflow port of the purge pump 70. The purge pump 70 sends the purge gas under pressure from its own outlet, and the purge gas sent from the purge pump 70 is supplied to the second pump passage 72 (pump side valve inlet 62A), the first switching valve 63, and the first canister passage 51 (canister side valve). It returns to the canister 50 via the outlet 61B).

[Backflow mode (Fig. 7)]
The reverse flow mode shown in FIG. 7 is an operation mode that is executed, for example, at the time of rapid acceleration during the operation state of the internal combustion engine or during a predetermined period immediately after the operation of the internal combustion engine is stopped. In the reverse flow mode, the first switching valve 63 is turned off and the second switching valve 64 is turned on. In the reverse flow mode, the purge pump 70 is driven for a predetermined period, and sucks the gas in the intake passage 22 toward the canister 50.

  In the backflow mode, the backflow prevention valve 82 is controlled to a closed state (energized state) by the control device 40 (see FIG. 1) to close the air introduction passage 54, and the purge valve 81 is controlled by the control device 40 (see FIG. 1). The opening is in the open state (energized state). The purge pump 70 is driven by the control device 40 (see FIG. 1), the first switching valve 63 is de-energized by the control device 40 (see FIG. 1), and the second switching valve 64 is controlled by the control device 40 (see FIG. 1). 1) is turned on. The dotted arrows in FIG. 7 indicate the direction in which the purge gas flows.

  The intake gas, which is the gas in the intake passage 22, passes through the purge passage 65 (intake passage side valve connection port 65A), the second switching valve 64, and the first pump passage 71 (pump side valve outlet 62B). 70 inlets. The purge pump 70 pumps intake gas from its own outlet, and the pumped intake gas is supplied to the second pump passage 72 (pump side valve inlet 62A), the first switching valve 63, and the first canister passage 51 (canister passage). It reaches the canister 50 via the side valve outlet 61B). Then, the evaporated fuel in the intake gas is adsorbed by the canister 50.

  As described above, the control device 40 switches the operation mode to one of the purge mode, the circulation mode, and the reverse flow mode in accordance with the operation state of the internal combustion engine, but the first switching valve 63 and the second switching valve 64 Is a solenoid type valve, so that it can be switched instantaneously (about several [ms]) as compared with a rotary type valve. Therefore, it is not necessary to stop the rotation of the purge pump 70 during the switching. In any of the operation modes, the heat of the coils 63C and 64C can be radiated by the flow of the purge gas (or the intake gas) through the valve bodies and the plungers of the first switching valve 63 and the second switching valve 64. It is possible to dissipate the heat of the valve unit 60.

● [State in which the fuel vapor processing apparatus 100 is mounted on a vehicle (FIG. 8)]
FIG. 8 shows an example of a state in which the evaporated fuel processing apparatus 100 is mounted on the vehicle C. As shown in FIG. 3, the moving direction of the movable body (plunger 63P, valve body 63V) of the first switching valve 63 in the valve unit 60 and the movable body (plunger 64P, valve body 64V) of the second switching valve 64 are changed. The moving directions are substantially parallel. When the fuel vapor treatment device 100 is mounted on the vehicle C, the moving direction of the movable body of the first switching valve 63 and the moving direction of the movable body of the second switching valve 64 are not substantially vertical but substantially horizontal. It is preferable to mount it on a computer. In the vehicle, the vibration level in the substantially horizontal direction is very small compared to the vibration level in the substantially vertical direction, so that the malfunction of the first switching valve 63 and the second switching valve 64 due to the vibration of the vehicle can be suppressed.

  The evaporative fuel treatment apparatus 100 according to the technology disclosed in the present specification is not limited to the configuration, the structure, the appearance, and the like described in the present embodiment, and various changes may be made without changing the gist of the technology disclosed in the present specification. , Addition and deletion are possible.

  In the description of the present embodiment, an example is described in which the purge valve 81 is provided in the purge passage 65. However, since the flow rate of the purge gas can be adjusted by controlling the rotation of the purge pump 70, the purge valve 81 may be omitted. .

  In the description of the present embodiment, a vehicle engine has been described as an example of an internal combustion engine. However, the present invention can be applied to various internal combustion engines.

DESCRIPTION OF SYMBOLS 1 Internal combustion engine control system 10 Air cleaner 10S Intake air amount detection means 10T Intake air temperature detection means 13 Throttle 13S Rotation angle detection means 15 Silencers 21, 22, 24 Intake passage 24S Pressure detection means 25 Intake manifold 25A Injector 26 Combustion chamber 27 Exhaust manifold 27S Air-fuel ratio detecting means 28, 29 Exhaust passage 29P Catalyst 30 Fuel tank 40 Control device 50 Canister 51 First canister passage 51A Canister inlet 51B Canister outlet 52 Second canister passage 53 Evaporated fuel introduction passage 54 Atmospheric introduction passage 60 Valve unit 61A Canister-side valve inlet 61B Canister-side valve outlet 61BS Restrictor 62A Pump-side valve inlet 62B Pump-side valve outlet 63 First switching valve 63C, 64C L 63D, 64D Elastic body 63H, 64H Through hole 63P, 64P Plunger 63R, 64R Seal member 63S, 64S Seal member 63V, 64V Valve body 63Y, 64Y Yoke 64 Second switching valve 65 Purge passage 65A Intake passage side valve connection port 65AS Throttle section 68 Pressure detecting means 70 Purge pump 71 First pump passage 71A Pump inflow 71B Pump outflow 72 Second pump passage 81 Purge valve 82 Backflow prevention valve 100 Evaporated fuel processing device T1A, T1B, T1C, T2A, T2B1, T2B2 , T2C passage

Claims (6)

A canister for adsorbing fuel vapor;
A purge passage for guiding a purge gas containing the evaporated fuel adsorbed by the canister to an intake passage of the internal combustion engine;
A purge pump for pumping the purge gas,
A valve unit that switches a connection state between the canister, the purge passage, and the purge pump;
In the evaporated fuel processing device having
The valve unit includes:
A canister-side valve inlet through which the purge gas flows from the canister;
A canister-side valve outlet capable of flowing out the purge gas to the canister,
A pump-side valve inlet into which the purge gas flows from the purge pump,
A pump-side valve outlet capable of flowing the purge gas to the purge pump,
An intake passage side valve connection port connected to the intake passage via the purge passage,
A first switching valve connected to an outlet of the purge pump via the pump-side valve inlet;
A second switching valve connected to an inlet of the purge pump via the pump-side valve outlet;
Has,
The first switching valve includes:
Solenoid valve type,
The connection destination of the pump-side valve inlet can be switched to one of the canister-side valve outlet or the intake passage-side valve connection,
The second switching valve includes:
Solenoid valve type,
The connection destination of the pump-side valve outlet can be switched to one of the canister-side valve inlet or the intake passage-side valve connection,
Evaporative fuel processing equipment. The evaporative fuel treatment device according to claim 1,
The canister-side valve outlet and the canister-side valve inlet are arranged substantially in parallel,
The pump-side valve outlet and the pump-side valve inlet are arranged substantially in parallel,
The pump-side valve outlet such that the extension direction of the pump-side valve outlet and the pump-side valve inlet is substantially perpendicular to the extension direction of the canister-side valve outlet and the canister-side valve inlet. And the pump-side valve inlet is disposed,
Evaporative fuel processing equipment. The evaporative fuel treatment device according to claim 1 or 2,
The yoke of the first switching valve and the yoke of the second switching valve are integrated,
Evaporative fuel processing equipment. An evaporative fuel treatment apparatus according to any one of claims 1 to 3,
The valve body and the plunger, which are movable bodies in the first switching valve, are integrated,
The valve body and the plunger, which are movable bodies in the second switching valve, are integrated,
Evaporative fuel processing equipment. An evaporative fuel treatment apparatus according to any one of claims 1 to 4,
In the non-energized state, the first switching valve connects the pump-side valve inlet to the canister-side valve outlet,
In the non-energized state, the second switching valve connects the pump-side valve outlet to the canister-side valve inlet,
Evaporative fuel processing equipment. An evaporative fuel treatment device according to any one of claims 1 to 5,
The moving direction of the movable body of the first switching valve and the moving direction of the movable body of the second switching valve are substantially parallel,
The moving direction is substantially horizontal when the fuel vapor processing device is mounted on a vehicle.
Evaporative fuel processing equipment.

Images