JP2019206924A - Evaporation fuel treatment device - Google Patents

Abstract

To provide an improved evaporation fuel treatment device.SOLUTION: An evaporation fuel treatment device comprises a canister, purge piping, a purge control valve and sealing piping. The canister adsorbs fuel which is evaporated in a fuel tank. The purge piping connects the canister and an intake pipe, and a purge gas which is sent to an internal combustion engine from the canister passes through the purge piping. The purge control valve is arranged on the purge piping. One end of the sealing pipe is connected to the intake pipe at a downstream side of a throttle valve, and the other end of the sealing pipe is sealed. In the evaporation fuel treatment device, the purge piping is connected to the intake pipe at an upstream side of the throttle valve, and has a purge gas pressure-feeding mechanism for feeding the purge gas to the intake pipe. Also, in the evaporation fuel treatment device, the sealing pipe is fixed to the purge piping, and a sealing state is maintained when the purge piping is normal, and the sealing state is not maintained when an abnormality occurs in the purge piping.SELECTED DRAWING: Figure 2

Description

  The present specification relates to a fuel vapor processing apparatus. In particular, the present invention relates to an evaporated fuel processing apparatus capable of detecting whether or not a connection between an intake pipe that supplies air to an internal combustion engine and a purge pipe that supplies evaporated fuel is good.

  Patent Document 1 discloses an evaporated fuel processing apparatus that supplies evaporated fuel evaporated in a fuel tank. The evaporated fuel processing apparatus of Patent Document 1 is used in a vehicle having a supercharger, and a purge pipe that supplies evaporated fuel to an intake pipe is branched into a first pipe and a second pipe. The first pipe supplies evaporated fuel to the intake pipe downstream from the throttle valve. The second pipe supplies the evaporated fuel to the intake pipe upstream from the throttle valve (upstream from the supercharger). Each of the first pipe and the second pipe is provided with a valve for opening and closing the pipe. Further, a pressure gauge is provided downstream from the valve of the second pipe.

JP 2007-89576 A

  In order to prevent the evaporated fuel from being released into the atmosphere, the evaporated fuel processing apparatus needs to detect that the purge pipe is disconnected from the intake pipe. That is, it is necessary to detect whether the connection between the purge pipe and the intake pipe is good or bad. For a pipe (first pipe) that supplies evaporated fuel downstream from the throttle valve, it is possible to easily detect whether or not the purge pipe is disconnected from the intake pipe by detecting the pressure downstream of the throttle valve. . However, regarding the pipe (second pipe) for supplying the evaporated fuel upstream from the throttle valve, the inside of the intake pipe is often at atmospheric pressure, and the purge pipe is disconnected from the intake pipe only by detecting the pressure in the intake pipe. It is difficult to detect whether or not.

  In Patent Document 1, it is detected whether the second pipe is disconnected from the intake pipe when the supercharger is driven and the evaporated fuel is not supplied (the purge pipe is closed). Yes. Specifically, when the supercharger is driven and the valve of the second pipe is closed, the pressure downstream of the valve is detected, and the detected pressure is compared with the atmospheric pressure. That is, Patent Document 1 detects whether or not the purge pipe (second pipe) is disconnected from the intake pipe only under specific conditions. In other words, the evaporative fuel processing apparatus of Patent Document 1 is configured such that when the evaporative fuel is supplied to the intake pipe (when the evaporative fuel is supplied to the intake pipe), the purge pipe is disconnected from the intake pipe. Cannot detect whether or not. As described above, whether or not the purge pipe is connected to the intake pipe is detected to prevent the evaporated fuel from being released into the atmosphere. Therefore, there is a need for an evaporative fuel processing apparatus that can detect the connection state of the purge pipe and the intake pipe, not only at specific conditions, but always when the evaporated fuel is supplied to the intake pipe. . It is an object of the present specification to provide an improved evaporated fuel processing apparatus capable of detecting a connection state between a purge pipe and an intake pipe.

  The first technique disclosed in the present specification may be an evaporated fuel processing apparatus that supplies evaporated fuel evaporated in a fuel tank to an intake pipe that supplies air to an internal combustion engine. The fuel vapor processing apparatus may include a canister, a purge pipe, a purge control valve, and a sealing pipe. The canister may adsorb the fuel evaporated in the fuel tank. The purge pipe connects the canister and the intake pipe, and purge gas sent from the canister to the internal combustion engine may pass through. The purge control valve may be provided on the purge pipe. The sealing pipe may have one end connected to the intake pipe downstream from the throttle valve and the other end sealed. In the fuel vapor processing apparatus, the purge pipe may be connected to the intake pipe upstream from the throttle valve, and may be provided with a purge gas pressure feeding mechanism that sends the purge gas to the intake pipe. Further, in the above evaporative fuel processing apparatus, the sealed pipe is fixed to the purge pipe. When the purge pipe is normal, the sealed state is maintained, and when the purge pipe is abnormal, the sealed pipe is sealed. May not be maintained.

  In the second technique disclosed in the present specification, in the first technique, the purge pipe may be a double pipe having an inner channel and an outer channel. The inner channel is a purge gas channel and may be connected to an intake pipe. The outer channel may be maintained in a sealed state when the inner channel is normal, and may not be maintained when an abnormality occurs in the inner channel. Further, the sealing pipe may be connected to the outer flow path.

  In the third technique disclosed in this specification, in the first or second technique, the intake pipe may be provided with a supercharger, and the purge pipe may be connected to the intake pipe upstream from the supercharger. .

  The fourth technique disclosed in the present specification may be an ejector in which the purge gas pumping mechanism is attached to the intake pipe in parallel with the supercharger in the third technique. In this case, the intake port of the ejector may be connected to the intake pipe between the supercharger and the throttle valve, and the exhaust port of the ejector may be connected to the purge pipe.

  The fifth technique disclosed in the present specification may be an evaporated fuel processing apparatus that supplies air to an internal combustion engine and supplies evaporated fuel evaporated in a fuel tank to an intake pipe provided with a supercharger. The fuel vapor processing apparatus may include a canister, a purge pipe, a purge control valve, and a sealing pipe. The canister may adsorb the fuel evaporated in the fuel tank. The purge pipe connects the canister and the intake pipe, and purge gas sent from the canister to the internal combustion engine may pass through. The purge control valve may be provided on the purge pipe. One end of the sealing pipe may be connected to the intake pipe between the throttle valve and the supercharger, and the other end may be sealed. In the fuel vapor processing apparatus, the purge pipe may be connected to the intake pipe upstream from the throttle valve, and may be provided with a purge gas pressure feeding mechanism that sends the purge gas to the intake pipe. In the above evaporative fuel processing apparatus, the sealed pipe is fixed to the purge pipe, and the sealed state is maintained when the purge pipe is normal, and the sealed state is maintained when an abnormality occurs in the purge pipe. It may not be done.

  In the sixth technique disclosed in this specification, in the first to fifth techniques, a branch pipe may be connected to the purge pipe downstream from the purge control valve and upstream from the purge gas pressure feeding mechanism. Further, the other end of the branch pipe may be connected to the intake pipe downstream from the throttle valve.

  In a seventh technique disclosed in this specification, in the first to sixth techniques, the evaporated fuel processing apparatus may further include a sensor that detects a pressure on the other end side of the sealing pipe.

  According to the first technique, when an abnormality occurs in the purge pipe (the purge pipe is disconnected or damaged), gas is introduced downstream of the throttle valve through the sealing pipe. Alternatively, gas leaks from the throttle valve through the sealing pipe. The pressure downstream of the throttle valve deviates from the control value, and as a result, for example, the air-fuel ratio deviates from the control value. By detecting whether or not there is a deviation from the control value, it is possible to detect whether or not the state of the purge pipe is normal. In the first technique, if the internal combustion engine is being driven, whether the purge pipe is in good condition can be detected regardless of whether the purge gas is supplied to the intake pipe.

  According to the second technique, since the sealed pipe is connected to the outer flow path, the flow path for detecting the quality of the purge gas flow path (inner flow path) and the purge pipe (outside to which the sealed pipe is connected). Flow path) is provided in a common pipe (purge pipe). It is possible to detect whether the purge pipe is connected or not with a simple structure.

  According to the third technique, the purge gas can be supplied to the intake pipe even while the supercharger is being driven (typically, the downstream of the supercharger is at a positive pressure). Also in the third technique, it is possible to detect the quality of the purge pipe regardless of whether the purge gas is supplied to the intake pipe.

  According to the fourth technique, it is possible to supply the purge gas to the intake pipe (upstream of the supercharger) by utilizing the phenomenon that the pressure between the supercharger and the throttle valve becomes positive during the operation of the supercharger.

  According to the fifth technique, when an abnormality occurs in the purge pipe, gas is introduced into the intake pipe between the throttle valve and the supercharger through the sealing pipe. Alternatively, gas leaks from the intake pipe through the sealing pipe. The supercharging pressure (pressure downstream of the supercharger) of the supercharger becomes lower than the control value, and as a result, for example, the air-fuel ratio deviates from the set value. Also in the fifth technique, it is possible to detect whether or not the state of the purge pipe is normal by detecting the presence or absence of deviation from the control value. Even in the fifth technique, it is possible to detect whether the purge pipe is good or not, regardless of whether or not the evaporated fuel is supplied to the intake pipe while the internal combustion engine is being driven.

  According to the sixth technique, the purge gas supply path can be changed according to the pressure of the intake pipe (intake manifold) downstream of the throttle valve. Specifically, when the pressure downstream of the throttle valve is negative, the purge gas can be supplied to the intake pipe through the branch path.

  According to the seventh technique, whether the state of the purge pipe is normal by comparing the pressure on the one end side of the sealing pipe (the pressure in the intake pipe where the sealing pipe is connected) with the pressure on the other end side. Can be detected.

1 shows an internal combustion engine system using a fuel vapor processing apparatus according to a first embodiment. The enlarged view of the connection part of an intake pipe and purge piping is shown. The enlarged view of the modification of the connection part of an intake pipe and purge piping is shown. The enlarged view of the modification of the connection part of an intake pipe and 1st purge piping is shown. The enlarged view of the modification of the connection part of an intake pipe and purge piping is shown. An internal combustion engine system using the evaporated fuel processing apparatus of the second embodiment is shown. An internal combustion engine system using a fuel vapor processing apparatus according to a third embodiment is shown. An internal combustion engine system using a fuel vapor processing apparatus according to a fourth embodiment is shown.

(First embodiment)
The evaporative fuel processing apparatus 10 will be described with reference to FIG. The evaporated fuel processing apparatus 10 is mounted on a vehicle such as an automobile. The evaporated fuel processing apparatus 10 is connected to a fuel supply system 2 that supplies fuel stored in the fuel tank FT to the engine EN.

(Fuel supply system)
The fuel supply system 2 supplies fuel injected from a fuel pump (not shown) accommodated in the fuel tank FT to the injector IJ. The injector IJ has an electromagnetic valve whose opening degree is adjusted by an ECU (Engine Control Unit) 100 described later. The injector IJ injects fuel into the engine EN.

  An intake pipe IP and an exhaust pipe EP are connected to the engine EN. The intake pipe IP is a pipe for supplying air to the engine EN by negative pressure of the engine EN or driving of the supercharger CH. A throttle valve TV is disposed in the intake pipe IP. The throttle valve TV is disposed downstream of the supercharger CH and upstream of the intake manifold IM. The amount of air flowing into the engine EN is controlled by adjusting the opening of the throttle valve TV. That is, the throttle valve TV controls the intake amount of the engine EN. The throttle valve TV is controlled by the ECU 100.

  A supercharger CH is arranged upstream of the throttle valve TV of the intake pipe IP. The supercharger CH is a so-called turbocharger, and rotates the turbine by the gas exhausted from the engine EN to the exhaust pipe EP, whereby the air in the intake pipe IP is pressurized and supplied to the engine EN. The supercharger CH is controlled by the ECU 100 to be driven when the rotational speed N of the engine EN exceeds a predetermined rotational speed (for example, 2000 rotations).

  An air cleaner AC is disposed upstream of the supercharger CH of the intake pipe IP. The air cleaner AC has a filter that removes foreign substances from the air flowing into the intake pipe IP. In the intake pipe IP, when the throttle valve TV is opened, the air passes through the air cleaner AC and is sucked into the engine EN. The engine EN burns fuel and air inside, and exhausts the exhaust pipe EP after combustion.

  The ECU 100 is connected to an air-fuel ratio sensor 62 disposed in the exhaust pipe EP. The ECU 100 detects the air-fuel ratio in the exhaust pipe EP from the detection result of the air-fuel ratio sensor 62, and controls the fuel injection amount from the injector IJ.

  The ECU 100 is connected to an air flow meter 56 disposed near the air cleaner AC. The air flow meter 56 is a so-called hot wire type aero flow meter, but may have other configurations. ECU 100 receives a signal indicating the detection result from air flow meter 56 and detects the amount of air supplied to intake pipe IP.

  In a situation where the supercharger CH is stopped, negative pressure is generated in the intake pipe IP (intake manifold IM) by driving the engine EN. On the other hand, in a situation where the supercharger CH is driven, the pressure downstream is higher than the supercharger CH, and the pressure upstream is higher than the supercharger CH.

(Evaporated fuel processing equipment)
The evaporated fuel processing apparatus 10 supplies the evaporated fuel (purge gas) in the fuel tank FT to the engine EN via the intake pipe IP. The evaporated fuel processing apparatus 10 includes a canister 14, a gas pipe 32, a purge control valve 34, and an ejector 40. The canister 14 adsorbs the evaporated fuel generated in the fuel tank FT. The canister 14 includes an activated carbon 14d and a case 14e that accommodates the activated carbon 14d. The case 14e has a tank port 14a, a purge port 14b, and an atmospheric port 14c. The tank port 14a is connected to the upper end of the fuel tank FT. As a result, the evaporated fuel in the fuel tank FT flows into the canister 14. The activated carbon 14d adsorbs evaporated fuel from the gas flowing from the fuel tank FT into the case 14e. Thereby, it is possible to prevent the evaporated fuel from being released into the atmosphere.

  The atmosphere port 14c communicates with the atmosphere via the air filter AF. The air filter AF removes foreign matter from the air flowing into the canister 14 through the atmospheric port 14c.

  The purge port 14 b communicates with the gas pipe 32. The gas pipe 32 is an example of a purge pipe. The gas pipe 32 includes a first pipe 22, a second pipe 26, and a third pipe 24. The first pipe 22 connects the canister 14 and the purge control valve 34. The second pipe 26 connects the purge control valve 34 and the intake pipe IP upstream of the supercharger CH. That is, the second pipe 26 is connected to the intake pipe IP upstream of the throttle valve TV. An ejector 40 is provided in the middle of the second pipe 26. The third pipe 24 connects the purge control valve 34 and the intake pipe IP downstream of the throttle valve TV. The third pipe 24 is an example of a branch pipe. It can also be said that the gas pipe 32 (first pipe 22) branches to the second pipe 26 and the third pipe 24 at a branch point 32 a downstream from the purge control valve 34. The pipes 22, 24 and 26 are made of a flexible material such as rubber or resin. Note that the pipes 22, 24, and 26 may be made of a metal material such as iron.

  The purge gas in the canister 14 flows from the canister 14 into the first pipe 22 through the purge port 14b. The purge gas in the first pipe 22 passes through the purge control valve 34 and is supplied into the intake pipe IP through the second pipe 26 and / or the third pipe 24.

  The third pipe 24 is connected to the intake manifold IM (downstream of the throttle valve TV). A check valve 83 is disposed at an intermediate position of the third pipe 24. The check valve 83 allows the gas to flow in the third pipe 24 toward the intake manifold IM, and prohibits the gas from flowing toward the canister 14. The second pipe 26 is connected to the suction port 40 a of the ejector 40. A check valve 80 is disposed at an intermediate position of the second pipe 26. The check valve 80 allows the gas to flow toward the intake pipe IP side in the second pipe 26 and prohibits the gas from flowing toward the canister 14 side.

  The purge control valve 34 is connected to the first pipe 22. That is, the purge control valve 34 is disposed in the gas pipe 32 upstream from the branch point 32a. When the purge control valve 34 is closed, the purge gas is stopped by the purge control valve 34 and does not flow into the second pipe 26 and the third pipe 24. On the other hand, when the purge control valve 34 is opened, it passes through the second pipe 26 and / or the third pipe 24 and flows into the intake pipe IP. The purge control valve 34 is an electronic control valve and is controlled by the ECU 100.

  The ejector 40 includes a suction port 40a, an intake port 40b, and an exhaust port 40c. The ejector is an example of a purge gas pressure feeding mechanism. An intake pipe 28a is connected to the intake port 40b. The intake pipe 28a connects the intake port 40b and the intake pipe IP downstream of the supercharger CH (between the supercharger CH and the throttle valve TV). An exhaust pipe 28b is connected to the exhaust port 40c. The exhaust pipe 28b connects the exhaust port 40c and the intake pipe IP upstream of the supercharger CH. A second pipe 26 is connected to the suction port 40a. The purge gas supplied to the second pipe 26 passes through the ejector 40 and is supplied into the intake pipe IP through the exhaust pipe 28b. The exhaust pipe 28 b is continuous with the second pipe 26 and can be regarded as a part of the second pipe 26. That is, it can be understood that the suction port 40 a and the exhaust port 40 c of the ejector 40 are connected to the middle of the second pipe 26. The second pipe 26 (exhaust pipe 28 b) is connected to the intake pipe IP at the connection portion 50.

  A pressure gauge 60 is attached to the intake pipe IP downstream of the throttle valve TV. In addition, a state detection pipe 70 is connected to the intake pipe IP downstream of the throttle valve TV. Specifically, the pressure gauge 60 and the state detection pipe 70 are attached to the intake manifold IM. Although details will be described later, the state detection pipe 70 is fixed to the exhaust pipe 28b (second pipe 26) with one end connected to the intake manifold IM and the other end sealed. The state detection pipe 70 is a pipe for detecting whether or not the second pipe 26 is normally connected to the intake pipe IP, and is an example of a sealed pipe.

  The ECU 100 includes a control unit 102 that controls the fuel supply system 2. The control unit 102 is disposed integrally with another part of the ECU 100 (for example, a part that controls the engine EN). Control unit 102 may be arranged separately from other parts of ECU 100. The control unit 102 includes a CPU and memories such as ROM and RAM. The control unit 102 controls the fuel supply system 2 according to a program stored in advance in the memory. Further, the control unit 102 outputs signals to the throttle valve TV and the purge control valve 34 to execute duty control. The control unit 102 adjusts the valve opening time of each valve TV, 34 by adjusting the duty ratio of the signal output to each valve TV, 34.

  When the supercharger CH is not driven, the intake manifold IM has a negative pressure under the control of the throttle valve TV. Therefore, when the control unit 102 opens the purge control valve 34, the purge gas passes from the canister 14 through the first pipe 22 and the third pipe 24 and is supplied to the intake manifold IM downstream of the supercharger CH. The When the supercharger CH is not driven, the pressure downstream of the supercharger CH is equal to the pressure upstream of the supercharger CH or lower than the pressure upstream of the supercharger CH. Therefore, no gas flows through the ejector 40 from the intake port 40b toward the exhaust port 40c. Since no negative pressure is generated in the suction port 40a, the purge gas does not pass through the second pipe 26 and is not supplied upstream of the supercharger CH.

  When the supercharger CH is driven, the pressure in the intake pipe IP downstream from the supercharger CH becomes positive. A pressure difference is generated between the intake port 40b and the exhaust port 40c of the ejector 40, and gas flows from the intake port 40b toward the exhaust port 40c. As a result, a negative pressure is generated in the suction port 40a, and the purge gas passes from the canister 14 through the first pipe 22, the second pipe 26, the ejector 40, and the exhaust pipe 28b, and the intake air upstream from the supercharger CH. Supplied in the tube IP. In addition, since the inside of the intake pipe IP downstream from the supercharger CH becomes a positive pressure, the purge gas does not pass through the third pipe 24.

  It should be noted that the supercharger CH is in the transition period from the stop state to the drive state (or from the drive state to the stop state), or when the supercharger CH is driven but the supercharger CH downstream is close to the atmospheric pressure. The purge gas may pass through both the second pipe 26 and the third pipe 24 and be supplied both upstream and downstream of the supercharger CH.

  As described above, when the supercharger CH is driven, the purge gas passes through the second pipe 26 (exhaust pipe 28b) and is supplied into the intake pipe IP upstream of the supercharger CH. At this time, if the second pipe 26 is disconnected from the intake pipe IP and / or the exhaust port 40c, the purge gas cannot be supplied to the intake pipe IP, and the purge gas is released to the atmosphere. Further, even when the second pipe 26 is damaged, the purge gas cannot be supplied to the intake pipe IP. That is, when an abnormality occurs in the second pipe 26, the purge gas cannot be supplied to the intake pipe IP. The evaporative fuel processing apparatus 10 can detect whether or not the state of the second pipe 26 is normal by using the state detection pipe 70.

(Connection between intake pipe and condition detection pipe)
FIG. 2 shows an enlarged view of the connecting portion 50 between the second pipe 26 and the intake pipe IP. The second pipe 26 is a double pipe and includes an inner pipe 26a and an outer pipe 26b surrounding the outer periphery of the inner pipe 26a. An inner channel 25a is provided inside the inner tube 26a. The purge gas supplied from the canister 14 moves through the inner flow path 25a. An outer flow path 25b is provided between the inner tube 26a and the outer tube 26b. A state detection pipe 70 is fixed to the second pipe 26. Specifically, the state detection pipe 70 is fixed to the outer pipe 26b, and the flow path in the state detection pipe 70 communicates with the outer flow path 25b. In addition, about the connection part of the 2nd piping 26 and the exhaust port 40c, since it is substantially the same as the connection part 50, description is abbreviate | omitted.

  An opening 52 is provided in the intake pipe IP. The intake pipe IP is provided with a connecting rib 54 surrounding the opening 52. The second pipe 26 is fixed to the intake pipe IP by connection ribs 54. Specifically, the second pipe 26 is connected to the intake pipe IP by fitting the connection rib 54 between the inner pipe 26a and the outer pipe 26b (that is, the outer flow path 25b). In a state where the second pipe 26 is connected to the intake pipe IP, the outer flow path 25b is sealed, and as a result, the flow path of the state detection pipe 70 is sealed. In a state where the second pipe 26 is connected to the intake pipe IP, the state detection pipe 70 is in a state where one end is connected to the intake manifold IM and the other end is sealed.

  When the second pipe 26 is detached from the intake pipe IP, that is, when the second pipe 26 is detached from the connection rib 54, the outer flow path 25b communicates with the atmosphere, and the other end of the state detection pipe 70 communicates with the atmosphere. As a result, the intake manifold IM communicates with the atmosphere via the state detection pipe 70 and the outer flow path 25b. The atmosphere is introduced into the intake manifold IM, or the gas in the intake manifold IM is released to the atmosphere. The pressure in intake manifold IM varies from the control value, and the air-fuel ratio deviates from the control value. Therefore, by monitoring the detection value of the pressure gauge 60, the detection value of the air-fuel ratio sensor 62, etc., the connection state of the second pipe 26 and the intake pipe IP (whether the second pipe 26 is normally connected to the intake pipe IP) Or not) can be detected.

  Even if the second pipe 26 is broken, the atmosphere is introduced into the intake manifold IM, or the gas in the intake manifold IM is released to the atmosphere. For example, when the inner pipe 26a of the second pipe 26 is broken, the inner pipe 26a and the outer pipe 26b communicate with each other. As a result, the gas in the inner pipe 26 a (purge gas) and the gas in the intake pipe IP (air) are introduced into the intake manifold IM through the outer pipe 26 b and the state detection pipe 70. Alternatively, the gas in the intake manifold IM is released to the atmosphere through the state detection pipe 70 and the pipe 26b. In either case, the pressure in the intake manifold IM varies from the control value, and the air-fuel ratio deviates from the control value. Even if the outer pipe 26b of the second pipe 26 is damaged, the state detection pipe 70 communicates with the atmosphere, and the pressure in the intake manifold IM varies from the control value.

(Modification 1 of connection part of intake pipe and state detection pipe)
FIG. 3 shows a partially enlarged view of the fuel vapor processing apparatus 10a (an enlarged view of the connecting portion 50a between the second pipe 26 and the intake pipe IP). The fuel vapor processing apparatus 10a is different from the fuel vapor processing apparatus 10 in the structure of the connecting portion 50a. In addition, about the fuel vapor processing apparatus 10a, about the same structure as the fuel vapor processing apparatus 10, description may be abbreviate | omitted by attaching | subjecting the same reference number as the fuel vapor processing apparatus 10. FIG. The fuel vapor processing apparatus 10a is different from the fuel vapor processing apparatus 10 in the shape of the connecting rib provided in the intake pipe IP. The form of the 2nd piping 26 and the state detection piping 70 is the same as the evaporative fuel processing apparatus 10 (refer also FIG. 2).

  As shown in FIG. 3, the intake pipe IP is provided with a first connection rib 54 a that surrounds the opening 52 and a second connection rib 54 b that surrounds the first connection rib. The first connection rib 54a is longer than the second connection rib 54b. In other words, the first connection rib 54a has a higher protruding height from the intake pipe IP than the second connection rib 54b. In the evaporated fuel processing apparatus 10a, the first connection rib 54a is fitted inside the inner pipe 26a (inner flow path 25a), and the second connection rib 54b is between the inner pipe 26a and the outer pipe 26b (outer flow path 25b). It fits in. In the fuel vapor processing apparatus 10a, since the first connection rib 54a is longer than the second connection rib 54b, the outer flow path 25b communicates with the atmosphere before the inner pipe 26a is detached from the first connection rib 54a. That is, when the connection state of the second pipe 26 to the intake pipe IP decreases (when the second pipe 26 is likely to be detached from the intake pipe IP), the state detection pipe 70 communicates with the atmosphere, and the intake manifold IM communicates with the atmosphere. . As a result, it can be detected that the second pipe 26 is not normally connected to the intake pipe IP. The evaporative fuel processing apparatus 10a can detect a problem before the second pipe 26 is detached from the intake pipe IP, and thus can more reliably prevent the purge gas from being released to the atmosphere.

(Modification 2 of connection part of intake pipe and state detection pipe)
FIG. 4 shows a partially enlarged view of the fuel vapor processing apparatus 10b (an enlarged view of the connecting portion 50b between the second pipe 26 and the intake pipe IP). About the fuel vapor processing apparatus 10b, about the same structure as the fuel vapor processing apparatus 10, description may be abbreviate | omitted by attaching | subjecting the same reference number as the fuel vapor processing apparatus 10. FIG.

  In the evaporated fuel processing apparatus 10 b, the second pipe 26 is a single pipe and is fitted to the connection rib 54. Further, the state detection pipe 70 (the flow path of the state detection pipe 70) is not connected to the second pipe 26. However, in the fuel vapor processing apparatus 10b, the second pipe 26 is fixed to the state detection pipe 70. Further, the intake pipe IP is provided with a protrusion 55 in the vicinity of the connection rib 54. The protruding height of the protruding portion 55 is smaller than the protruding height of the connecting rib 54. In the evaporated fuel processing apparatus 10 b, the second pipe 26 is fitted to the connection rib 54, and the state detection pipe 70 is fitted to the protrusion 55. As described above, the state detection pipe 70 and the second pipe 26 are fixed. Therefore, when the connection state of the second pipe 26 with respect to the intake pipe IP is lowered, the state detection pipe 70 is detached from the projecting portion 55, and the intake manifold IM and the atmosphere communicate with each other through the state detection pipe 70. Thereby, it can be detected that the second pipe 26 is not normally connected to the intake pipe IP. The protruding height of the protruding portion 55 may be equal to the protruding height of the connection rib 54. In this case, when the second pipe 26 is detached from the intake pipe IP, the state detection pipe 70 is detached from the projecting portion 55, and the intake manifold IM and the atmosphere communicate with each other through the state detection pipe 70.

(Modification 3 of connection part of intake pipe and state detection pipe)
FIG. 5 shows a partially enlarged view of the fuel vapor processing apparatus 10c (an enlarged view of the connecting portion 50c between the second pipe 26 and the intake pipe IP). About the fuel vapor processing apparatus 10c, about the same structure as the fuel vapor processing apparatus 10, description may be abbreviate | omitted by attaching | subjecting the same reference number as the fuel vapor processing apparatus 10. FIG. In the evaporated fuel processing apparatus 10c, a pressure gauge 58 is attached to the state detection pipe 70. Using the detected value of the pressure gauge 58, for example, by comparing with the pressure gauge 60 attached to the intake manifold IM, whether or not the state of the second pipe 26 is normal (abnormality such as disconnection or damage). Presence / absence) can be detected. The structure of the connecting portion 50c (the pressure gauge 58 is attached to the state detection pipe 70) can also be applied to the evaporated fuel processing apparatuses 10a and 10b.

(Second embodiment)
With reference to FIG. 6, the evaporative fuel processing apparatus 210 will be described. The evaporative fuel processing apparatus 210 is a modification of the evaporative fuel processing apparatus 10, and the description of the evaporative fuel processing apparatus 210 that is the same as that of the evaporative fuel processing apparatus 10 may be omitted by giving the same reference numerals. . In the evaporated fuel processing apparatus 210, an ejector is not provided on the second pipe 26, and a pump 72 is disposed. The pump 72 is a so-called vortex pump (also called a cascade pump or a Wesco pump). The pump 72 is controlled by the ECU 100. By using the pump 72, the purge gas can be pumped from the second pipe 26 into the intake pipe IP. The pump 72 is an example of a purge gas pressure feeding mechanism. In the fuel vapor processing apparatus 210, the connection part 50a (FIG. 3), the connection part 50b (FIG. 4), and the connection part 50c (FIG. 5) are applied as the structure of the connection part 50 between the second pipe 26 and the intake pipe IP. You can also

(Third embodiment)
With reference to FIG. 7, the evaporative fuel processing apparatus 310 will be described. The evaporative fuel processing device 310 is a modification of the evaporative fuel processing device 10, and the description of the evaporative fuel processing device 310 that is the same as that of the evaporative fuel processing device 10 may be omitted by giving the same reference numerals. . In the evaporated fuel processing device 310, one end of the state detection pipe 370 is connected to the intake pipe IP between the throttle valve TV and the supercharger CH, and the other end is fixed to the second pipe 26. In the fuel vapor processing apparatus 310, the connection part 50a (FIG. 3), the connection part 50b (FIG. 4), and the connection part 50c (FIG. 5) are applied as the structure of the connection part 50 between the second pipe 26 and the intake pipe IP. You can also Moreover, it can replace with the ejector 40 and can also supply purge gas to the intake pipe IP using a pump (refer FIG. 6).

  In the evaporated fuel processing device 310, when an abnormality occurs in the second pipe 26, gas leaks from the intake pipe IP between the throttle valve TV and the supercharger CH through the state detection pipe 370. When the supercharger CH is driven in this state, the pressure downstream of the supercharger CH becomes lower than the control value, the pressure of the intake manifold IM (detected value of the pressure gauge 60), the air-fuel ratio (detected value of the air-fuel ratio sensor 62). ) Deviates from the control value. Also in the evaporative fuel processing device 310, it is possible to detect whether or not the state of the second pipe 26 is normal by monitoring the detection value of the pressure gauge 60, the detection value of the air-fuel ratio sensor 62, and the like.

(Fourth embodiment)
With reference to FIG. 8, the evaporative fuel processing apparatus 410 will be described. The evaporative fuel processing apparatus 410 is a modification of the evaporative fuel processing apparatus 10, and the description of the evaporative fuel processing apparatus 410 that is the same as the evaporative fuel processing apparatus 10 may be omitted by giving the same reference numerals. . The evaporated fuel processing apparatus 410 does not have a branch pipe (third pipe 24). Therefore, in the evaporated fuel processing device 410, the purge gas is supplied only upstream of the throttle valve TV (upstream of the supercharger CH). Compared with the evaporated fuel processing apparatus 10, the evaporated fuel processing apparatus 410 can omit the number of parts (specifically, the third pipe 24 and the check valve 83). In addition, the structure which abbreviate | omits branch piping (pipe which supplies purge gas to an intake manifold) can also be applied to the evaporative fuel processing apparatus 210,310.

  As mentioned above, although embodiment of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

10: Evaporative fuel processing device 14: Canister 32: Purge pipe 34: Purge control valve 40: Purge gas pressure feed mechanism (ejector)
70: Sealing pipe 72: Purge gas pressure feeding mechanism (pump)
EN: Internal combustion engine FT: Fuel tank IP: Intake pipe TV: Throttle valve

Claims (7)

An evaporative fuel processing apparatus for supplying fuel evaporated in a fuel tank to an intake pipe for supplying air to an internal combustion engine,
The evaporative fuel processing device
A canister that adsorbs fuel evaporated in the fuel tank;
A purge pipe that connects the canister and the intake pipe and through which purge gas sent from the canister to the internal combustion engine passes;
A purge control valve provided on the purge pipe;
A downstream end of the throttle valve is connected to the intake pipe, and the other end is sealed.
The purge pipe is connected to the intake pipe upstream from the throttle valve, and is provided with a purge gas pressure feeding mechanism for sending purge gas to the intake pipe.
The sealed piping is fixed to the purge piping, and when the purge piping is normal, the sealed state is maintained, and when the abnormality occurs in the purge piping, the evaporated fuel processing apparatus is not maintained. . It is an evaporative fuel processing apparatus of Claim 1, Comprising:
The purge pipe is a double pipe having an inner channel and an outer channel,
The inner flow path is a purge gas flow path and is connected to the intake pipe.
The outer channel is maintained in the sealed state when the inner channel is normal, and the sealed state is not maintained when an abnormality occurs in the inner channel,
The evaporated fuel processing apparatus, wherein the sealing pipe is connected to the outer flow path. It is an evaporative fuel processing apparatus of Claim 1 or 2, Comprising:
There is a turbocharger in the intake pipe,
An evaporative fuel processing apparatus, wherein the purge pipe is connected to the intake pipe upstream from the supercharger. The evaporative fuel processing apparatus according to claim 3,
The purge gas pressure feeding mechanism is an ejector attached to the intake pipe in parallel with the supercharger,
The intake port of the ejector is connected to the intake pipe between the turbocharger and the throttle valve,
An evaporative fuel processing apparatus in which an exhaust port of an ejector is connected to a purge pipe. An evaporative fuel processing apparatus that supplies air to an internal combustion engine and supplies evaporative fuel evaporated in a fuel tank to an intake pipe provided with a supercharger,
The evaporative fuel processing device
A canister that adsorbs fuel evaporated in the fuel tank;
A purge pipe that connects the canister and the intake pipe and through which purge gas sent from the canister to the internal combustion engine passes;
A purge control valve provided on the purge pipe;
One end is connected to the intake pipe between the throttle valve and the supercharger, and the other end is sealed.
The purge pipe is connected to the intake pipe upstream from the throttle valve, and is provided with a purge gas pressure feeding mechanism for sending purge gas to the intake pipe.
The sealed piping is fixed to the purge piping, and when the purge piping is normal, the sealed state is maintained, and when the abnormality occurs in the purge piping, the evaporated fuel processing apparatus is not maintained. . It is an evaporative fuel processing apparatus as described in any one of Claim 1 to 5, Comprising:
A branch pipe is connected to the purge pipe downstream from the purge control valve and upstream from the purge gas pumping mechanism.
An evaporative fuel processing apparatus, wherein the other end of the branch pipe is connected to the intake pipe downstream from the throttle valve. It is an evaporative fuel processing apparatus as described in any one of Claim 1 to 6, Comprising:
Furthermore, an evaporative fuel processing apparatus provided with the sensor which detects the pressure of the other end side of sealing piping.

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