JP2001295689A - Diagnosing device for evaporation purging system, and control device for vehicle loaded with the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diagnosing device for an evaporation purging system and a control device for a vehicle loaded with the device, capable of quickly reducing the internal pressure of an evaporated fuel processing mechanism by keeping the negative pressure of an intake passage high in introducing the negative pressure into the evaporated fuel processing mechanism. SOLUTION: In introducing negative pressure of the intake passage 70 into an evaporation system so that the pressure in the evaporation system reaches a designated negative pressure to determine whether a hole is bored or not in the evaporation system, the upper limit value of an opening is changed to the valve closing side as compared with that in normal operation, so that even if a high load is requested in the vehicle 20, a throttle valve 74 will not open to a large size. In this case, the negative pressure generated in the intake passage 70 is kept larger, as compared with that in the case where the upper limit value of the throttle opening is not changed to the valve closing side, so that the pressure in the evaporation system can be reduced quickly and surely to a prescribed negative pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diagnostic device for an evaporative purge system and a control device for a vehicle equipped with the device. More particularly, the present invention relates to a device for adsorbing fuel vapor generated in a fuel tank and removing the adsorbed fuel fuel. The present invention relates to a diagnostic device for an evaporative purge system for purging toward an intake passage using a negative pressure generated in an intake passage of an internal combustion engine, and a control device for a vehicle equipped with the device.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 9-30321
As disclosed in No. 4, in order to prevent evaporative fuel (vapor) generated in a fuel tank from being released into the atmosphere, the vapor is adsorbed to a canister, and the adsorbed vapor is removed at an appropriate time from an internal combustion engine. There is known an evaporative purge system for purging toward an intake passage. In a system of this system (hereinafter, referred to as an evaporative system), a pipe may be disconnected or broken, or a hole may be opened in a fuel tank. When such a situation occurs, fuel leaks from the site into the atmosphere. Therefore, in the evaporative purge system, it is necessary to reliably determine whether any unnecessary holes are opened in the evaporative system. Hereinafter, this determination is referred to as an evaporative hole determination.

[0003] As a method of determining whether or not an unnecessary hole is opened in the evaporation system, a pressure in the evaporation system is reduced by introducing a negative pressure generated in an intake passage into the evaporation system. It is conceivable to close the system after the internal pressure reaches a predetermined value and detect the subsequent pressure in the evaporation system. As a result, when the pressure in the evaporation system rapidly increases toward the atmospheric pressure, it can be determined that an unnecessary hole is opened in the system. On the other hand, when the degree of pressure increase in the evaporation system is small, it can be determined that unnecessary holes are not opened in the evaporation system. Therefore, according to the above-described method, it is possible to determine the evaporation system hole based on the pressure in the evaporation system.

However, if the negative pressure generated in the intake passage when introducing a negative pressure into the evaporation system is small, that is, if the pressure in the intake passage is large on the positive pressure side, the negative pressure is quickly introduced into the system. Since it is not introduced, it takes a lot of time to reach a predetermined value in the system, or
The pressure in the system cannot reach a predetermined value. While the negative pressure in the intake passage is being introduced into the evaporative system so that the pressure in the evaporative system reaches a predetermined value, the fuel adsorbed in the canister cannot be effectively purged toward the intake passage. For this reason, when the evaporative system hole determination is performed even under a situation where the pressure in the intake passage is large on the positive pressure side, the situation in which the fuel adsorbed in the canister cannot be purged continues for a long time, and the evaporative emission deteriorates. Would.

Therefore, in the above conventional system,
If the pressure in the intake passage is larger than a predetermined value, the evaporative system hole determination is prohibited or interrupted. For this reason,
According to the above-described conventional system, even when the pressure in the intake passage is large, the situation in which the fuel adsorbed in the canister cannot be purged does not continue for a long time, so that it is possible to prevent deterioration of the evaporative emission.

[0006]

By the way, if the negative pressure generated in the intake passage when the negative pressure is introduced into the evaporative system does not decrease, that is, if the pressure in the intake passage is maintained at a low level, it is not possible to reduce the negative pressure. Since the negative pressure is quickly introduced into the system, it is possible to quickly determine the evaporative system hole, and to avoid a situation in which the fuel adsorbed in the canister cannot be purged for a long time. However, in the above-mentioned conventional system, no processing is performed for maintaining the negative pressure in the intake passage at a large state when introducing the negative pressure into the evaporative system.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned points, and maintains a large negative pressure in an intake passage when introducing a negative pressure into an evaporative fuel processing mechanism, thereby reducing the evaporative fuel processing mechanism. It is an object of the present invention to provide a diagnostic device for an evaporative purge system capable of rapidly reducing the internal pressure, and a control device for a vehicle equipped with the device.

[0008]

The above object is achieved by the present invention.
An evaporative fuel processing mechanism for adsorbing the evaporative fuel generated in the fuel tank and purging the adsorbed evaporative fuel toward the intake passage using a negative pressure generated in the intake passage of the internal combustion engine, After the introduction of the negative pressure of the intake passage to the evaporative fuel processing mechanism is started, the state of the evaporative fuel processing mechanism is changed based on the internal pressure after the internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure. An evaporative purge system diagnostic device comprising: a determination unit configured to determine an upper limit value of an opening degree of a throttle valve provided in the intake passage when the determination is performed by the state determination unit. This is achieved by a diagnostic device for an evaporative purge system, comprising: an opening upper limit value changing unit that changes to a valve closing side as compared with a case where the determination by the unit is not performed.

According to the first aspect of the present invention, the evaporated fuel processing mechanism absorbs the evaporated fuel generated in the fuel tank and directs the absorbed evaporated fuel to the intake passage by utilizing the negative pressure of the intake passage. Purge. After the introduction of the negative pressure of the intake passage to the evaporative fuel processing mechanism is started, the state determining means determines whether or not the evaporative fuel processing mechanism has an internal pressure based on the internal pressure after the internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure. Determine the status. In the present invention, when the determination by the state determination means is performed, the upper limit value of the opening degree of the throttle valve provided in the intake passage is changed to the valve closing side as compared with the case where the determination is not performed. . In this case, since the throttle valve is prevented from being greatly opened, a large negative pressure is secured in the intake passage downstream of the throttle valve. Therefore, according to the present invention, the internal pressure of the evaporative fuel treatment mechanism can be rapidly reduced.

As the atmospheric pressure decreases, the amount of air flowing through the intake passage decreases. For this reason, even if the opening degree of the throttle valve is the same, as the atmospheric pressure decreases, the negative pressure generated in the intake passage decreases, and it becomes difficult to quickly reduce the internal pressure of the evaporative fuel treatment mechanism.

Therefore, as set forth in claim 2, in the diagnostic apparatus for an evaporative purge system according to claim 1, the opening degree upper limit value changing means changes the upper limit value of the opening degree of the throttle valve in accordance with the atmospheric pressure. It may be changed.

When the upper limit of the opening of the throttle valve is changed to the valve closing side, the amount of intake air decreases, and the output generated in the internal combustion engine decreases. In this case, claim 1
Alternatively, in a vehicle equipped with the evaporative purge system described in 2, the driving force is reduced.

Therefore, in order to solve such inconvenience,
According to a third aspect of the present invention, there is provided a control device for a vehicle equipped with the evaporative purge system diagnostic device according to the first or second aspect, wherein the vehicle includes an internal combustion engine and a power source other than the internal combustion engine. If the output of the internal combustion engine is reduced by changing the upper limit of the opening of the throttle valve to the valve closing side by the opening upper limit changing means, the internal combustion engine is reduced by the reduced output. Output changing means for increasing the output of the power source other than the above may be provided.

According to the third aspect of the present invention, the vehicle is a hybrid vehicle having an internal combustion engine and a power source other than the internal combustion engine. When the output of the internal combustion engine is reduced by changing the upper limit of the opening of the throttle valve to the valve closing side,
The output of a power source other than the internal combustion engine is increased. For this reason,
According to the present invention, even when the output of the internal combustion engine is reduced by changing the upper limit of the opening degree of the throttle valve to the valve closing side in order to quickly reduce the internal pressure of the evaporative fuel treatment mechanism, the driving force of the vehicle is reduced. Can be prevented from decreasing.

According to a fourth aspect of the present invention, the fuel vapor generated in the fuel tank is adsorbed, and the adsorbed fuel vapor is directed toward the intake passage by utilizing a negative pressure generated in the intake passage of the internal combustion engine. An evaporative purge system comprising: an evaporative fuel processing mechanism for purging; and a negative pressure introducing means for introducing a negative pressure generated in the intake passage to the evaporative fuel processing mechanism so that the internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure. A time calculating means for accumulating a time when the pressure generated in the intake passage is less than a predetermined value after the introduction of the negative pressure by the negative pressure introducing means is started, and the time calculating means Determination means for determining whether or not the internal pressure of the evaporative fuel treatment mechanism has reached the predetermined negative pressure, based on whether or not the cumulative time accumulated by (i) has reached a predetermined time. Eva Diagnostic apparatus for purging the system, the internal pressure of the evaporative fuel processing mechanism is effective in determining accurately whether the host vehicle has reached the predetermined negative pressure.

According to a fourth aspect of the present invention, the time calculating means is provided after the introduction of the negative pressure generated in the intake passage to the evaporative fuel processing mechanism is started so that the internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure. The time when the pressure generated in the intake passage is less than a predetermined value is accumulated. That is, when the pressure generated in the intake passage is equal to or higher than the predetermined value, the internal pressure of the evaporative fuel treatment mechanism cannot be effectively reduced, so that time accumulation is not performed. The determining means is based on whether or not the accumulated time accumulated by the time calculating means has reached a predetermined time.
It is determined whether or not the internal pressure of the evaporated fuel processing mechanism has reached a predetermined negative pressure. Therefore, according to the present invention, it is possible to accurately determine whether or not the internal pressure of the evaporated fuel processing mechanism has reached the predetermined negative pressure.

If the pressure in the intake passage increases while the negative pressure generated in the intake passage is being introduced to the evaporative fuel treatment mechanism so that the internal pressure of the evaporative fuel treatment mechanism reaches a predetermined negative pressure, When the negative pressure decreases, the negative pressure in the evaporative fuel treatment mechanism may decrease. For this reason, it is not possible to accurately determine whether or not the internal pressure of the evaporative fuel treatment mechanism has reached the predetermined negative pressure only by the accumulated time when the pressure generated in the intake passage is less than the predetermined value.

Therefore, in the diagnostic apparatus for an evaporative purge system according to the present invention, the time calculating means may be configured such that the time calculating means starts the intake air after the negative pressure introducing means starts introducing the negative pressure. When the pressure generated in the passage becomes equal to or more than a predetermined value, the accumulated time may be subtracted or reset.

According to a sixth aspect of the present invention, the fuel vapor generated in the fuel tank is adsorbed and the adsorbed fuel vapor is directed toward the intake passage by utilizing a negative pressure generated in the intake passage of the internal combustion engine. An evaporative fuel processing mechanism for purging, a negative pressure introducing means for introducing a negative pressure generated in the intake passage to the evaporative fuel processing mechanism so that an internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure, and the negative pressure introducing means Based on whether the time after the introduction of the negative pressure has started has reached a predetermined time,
Determining means for determining whether or not the internal pressure of the evaporative fuel processing mechanism has reached the predetermined negative pressure, wherein the introduction of the negative pressure by the negative pressure introducing means is started. After that, when the pressure generated in the intake passage becomes equal to or higher than a predetermined value, the diagnosis apparatus for the evaporative purge system further includes a time extension unit for extending the predetermined time. This is effective in accurately determining whether or not a negative pressure has been reached.

According to a sixth aspect of the present invention, the determining means determines whether the internal pressure of the evaporative fuel treatment mechanism reaches a predetermined negative pressure after the introduction of the negative pressure generated in the intake passage to the evaporative fuel treatment mechanism is started. It is determined whether or not the internal pressure of the evaporated fuel processing mechanism has reached the predetermined negative pressure based on whether or not the time has reached a predetermined time. The time extending means extends the predetermined time when the pressure generated in the intake passage becomes equal to or more than a predetermined value after the introduction of the negative pressure is started. Therefore, according to the present invention, it is possible to accurately determine whether or not the internal pressure of the evaporated fuel processing mechanism has reached the predetermined negative pressure.

Further, as described in claim 7, the fuel vapor generated in the fuel tank is adsorbed, and the adsorbed fuel vapor is directed toward the intake passage by utilizing a negative pressure generated in the intake passage of the internal combustion engine. An evaporative fuel processing mechanism for purging, a negative pressure introducing means for introducing a negative pressure generated in the intake passage to the evaporative fuel processing mechanism so that an internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure, and the negative pressure introducing means The internal pressure of the evaporative fuel treatment mechanism is determined based on whether or not the integrated value of the flow rate of the gas flowing from the evaporative fuel treatment mechanism to the intake passage after the introduction of the negative pressure due to has reached a predetermined value. A determination unit for determining whether or not the predetermined negative pressure has been reached, wherein the diagnostic device is provided in the intake passage after the negative pressure is started to be introduced by the negative pressure introducing unit. Pressure is a predetermined value In the case of the above, the diagnostic device for the evaporative purge system, further comprising a reset unit for resetting the integrated value, accurately determines whether or not the internal pressure of the evaporative fuel processing mechanism has reached a predetermined negative pressure. It is effective on the above.

In the invention described in claim 7, the determining means is provided for starting the introduction of the negative pressure generated in the intake passage to the evaporative fuel processing mechanism so that the internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure. It is determined whether or not the internal pressure of the evaporative fuel processing mechanism has reached a predetermined negative pressure based on the integrated value of the flow rate of the gas flowing from the evaporative fuel processing mechanism to the intake passage. If the negative pressure in the intake passage is reduced while the negative pressure in the intake passage is being introduced into the evaporative fuel processing mechanism, the negative pressure in the evaporative fuel processing mechanism may be reduced. Therefore, it is not possible to accurately determine whether or not the internal pressure of the evaporative fuel processing mechanism has reached a predetermined negative pressure based on the integrated value of the flow rate of the gas flowing from the evaporative fuel processing mechanism to the intake passage. Therefore, in the present invention, when the negative pressure generated in the intake passage becomes equal to or more than a predetermined value, the reset unit resets the integrated value.
Therefore, according to the present invention, it is possible to accurately determine whether or not the internal pressure of the evaporated fuel processing mechanism has reached the predetermined negative pressure.

[0023]

FIG. 1 is a diagram schematically showing a drive mechanism of a vehicle 20 equipped with an evaporative purge system diagnostic device according to one embodiment of the present invention. The system of this embodiment includes a hybrid electronic control unit (hereinafter, referred to as a hybrid ECU) 22, an engine electronic control unit (hereinafter, referred to as an engine ECU) 24, and a motor electronic control unit (hereinafter, referred to as a motor ECU). 2)
6 is provided.

As shown in FIG. 1, in this embodiment, the vehicle 20 has an axle 30 connecting the left wheel FL and the right wheel FR.
It has. A speed reducer 32 is fixed to the axle 30. A planetary gear mechanism 36 is engaged with the speed reducer 32 via a gear 34. The planetary gear mechanism 36 includes the internal combustion engine 4
A planetary carrier connected to the output shaft of No. 0, a ring gear connected to the output shaft of the electric motor 42, and a sun gear connected to the output shaft of the generator 44.

A battery 50 is connected to the generator 44 and the electric motor 42 via an inverter 46 and a main relay 48. The motor ECU 26 is connected to the inverter 46, and the hybrid ECU 22 is connected to the main relay 48. The main relay 48 has a function of supplying power from the battery 50 to the inverter 46 by receiving a drive signal from the hybrid ECU 22. In addition, the inverter 46
Is between the battery 50 and the generator 44, and
A three-phase bridge circuit composed of a plurality of power transistors is provided between the battery 50 and the electric motor 42, and has a function of converting a DC current and a three-phase AC current between them. ing. When the inverter 46 is appropriately driven by the motor ECU 26, the generator 44 and the electric motor 42 are controlled at a rotation speed corresponding to the frequency of the AC current, and generate a torque corresponding to the magnitude of the current. I do.

The generator 44 has a function as a starter motor for starting the internal combustion period 40 by supplying power from the battery 50 when the start of the internal combustion engine 40 is not completed. After completion, it has a function as a generator for supplying electric power to the battery 50 or the electric motor 42 via the inverter 46 by the output of the internal combustion engine 40. The electric motor 42
Has a function as an electric motor that generates torque for assisting the output of the internal combustion engine 40 when power is supplied during normal running, and is supplied to the battery 50 via the inverter 46 by the rotation of the axle 30 during braking. It has a function as a power supply generator.

The battery 50 is connected to the above-described hybrid ECU 22. Hybrid ECU 22
Monitors the state of charge of the battery 50, that is, the remaining capacity.

The internal combustion engine 40 includes the engine EC described above.
U24 is connected. The internal combustion engine 40 includes an engine E
When a drive signal is supplied from the CU 24, an output corresponding to the drive signal is generated.

In this embodiment, the vehicle 20 is a hybrid vehicle that generates power by appropriately combining an internal combustion engine 40 and an electric motor 42. Hybrid ECU 22
The accelerator opening sensor 52 outputs a signal corresponding to the amount of depression of the accelerator pedal (hereinafter referred to as accelerator opening ACCP), and a vehicle speed sensor that outputs a pulse signal at a cycle corresponding to the vehicle speed SPD of the vehicle 20. 54 are connected. Hybrid ECU 22 detects accelerator opening ACCP and vehicle speed SPD based on the output signal of accelerator opening sensor 52 and the output signal of vehicle speed sensor 54.

The hybrid ECU 22 determines the vehicle 20 based on the detected accelerator opening ACCP and vehicle speed SPD.
After calculating the driving force required for, the internal combustion engine 40 computes the required output W _E of the engine 40 to operate efficiently for the driving force, the required output W of the electric motor 42
Calculate _M. The hybrid ECU 22 includes the engine E
CU24 and is connected to the motor ECU 26, so the required output _{W E} is generated in the internal combustion engine 40 to the engine ECU 24, also, as the required output _{W M} in the electric motor 42 to the motor ECU 26 is generated, Each supplies a drive signal.

FIG. 2 shows a system configuration diagram of the evaporative purge system of this embodiment. The system of the present embodiment includes a fuel tank 60 whose outer periphery is covered with a member made of iron.
The inside of the fuel tank 60 is separated by a bladder membrane 62 into a fuel chamber 64 in which fuel is stored and a gas chamber 66 in which gas is filled. The bladder film 62 is made of a member such as a resin that can expand and contract, and can expand and contract inside the fuel tank 60 according to the amount of fuel stored in the fuel chamber 64.

An air cleaner 72 disposed in an intake passage 70 of the internal combustion engine 40 communicates with the fuel tank 60 via an air introduction passage 68. The air cleaner 72 has a function of filtering air taken into the internal combustion engine 40 (hereinafter, referred to as intake air). A throttle valve 74 for adjusting the amount of intake air is provided downstream of the air cleaner 72 in the intake passage 70. A throttle actuator 76 is connected to the throttle valve 74. The engine ECU 24 is connected to the throttle actuator 76. When a drive signal is supplied from the engine ECU 24, the throttle actuator 76 drives the throttle valve 74 to an opening corresponding to the drive signal.

In the vicinity of the throttle valve 74, a throttle opening sensor 7 for outputting a signal corresponding to the opening of the throttle valve 74 (hereinafter referred to as the throttle opening TA).
8 are provided. The output signal of the throttle opening sensor 78 is supplied to the engine ECU 24. The engine ECU 24 detects the throttle opening TA based on the output signal of the throttle opening sensor 78.

An air flow meter 80 is provided in the intake passage 70 between the air cleaner 72 and the throttle valve 74. The air flow meter 80 measures the mass of air that has passed through the air cleaner 72 per unit time (hereinafter referred to as the mass).
A signal is output according to the intake air amount Ga). The output signal of the air flow meter 80 is supplied to the engine ECU 24. Engine ECU 24 detects intake air amount Ga based on the output signal of air flow meter 80.

A canister close valve (hereinafter referred to as CCV) 82 is provided at an end of the air introduction passage 68 on the gas chamber 66 side. The CCV 82 is a two-position solenoid valve that is normally kept open and is closed when a drive signal is supplied from the engine ECU 24. In such a configuration, when the CCV 82 is open, the gas chamber 66 communicates with the atmosphere via the air cleaner 72 and the intake passage 70.

A filler pipe 84 provided for supplying fuel from the outside is connected to the fuel chamber 64.
A fuel cap 86 is provided at the air opening of the filler pipe 84.
Is detachably attached. Further, one end of a lower communication passage 88 is connected to the fuel chamber 64 on the lower surface thereof, and one end of an upper communication passage 90 is connected to the upper surface thereof. The other ends of the lower communication passage 88 and the upper communication passage 90 are
Both are connected to a volume-invariant sub-tank 92 stored in the fuel tank 60. The sub-tank 92 has a built-in fuel pump (not shown). The fuel pumped by the fuel pump is adjusted to a predetermined pressure and then supplied to a fuel injection valve (not shown) for injecting fuel into the internal combustion engine 40 via a fuel supply path (not shown). Is done.

A first vapor discharge passage 94 connected to the above-described filler pipe 84 is connected to an upper portion of the sub tank 92. The first vapor discharge passage 94 is connected to the fuel tank 6.
0 is a passage for discharging fuel vapor (vapor) generated in the fuel chamber 64 and the sub tank 92. Part of the vapor flowing through the first vapor discharge passage 94 is liquefied by contacting fuel adhering to the wall surface of the filler pipe 84,
Thereafter, the fuel is collected in the fuel chamber 64 of the fuel tank 60.

One end of a second vapor discharge passage 96 is connected to the filler pipe 84. The second vapor discharge passage 96 is a passage for discharging the vapor generated in the fuel chamber 64 and the sub-tank 92 and the vapor flowing directly from the fuel chamber 64 into the filler pipe 84. The other end of the second vapor discharge passage 96 is connected to a vapor introduction hole 100a of the canister 100. Therefore, the fuel generated in the fuel tank 60 is guided to the canister 100 through the second vapor discharge passage 96. Canister 100
Is made of activated carbon that adsorbs vapor, and has a function of adsorbing fuel generated in the fuel tank 60.

The canister 100 has a vapor introduction hole 100
The fuel purge hole 100b is provided on the same side as that of FIG. In the fuel purge hole 100b of the canister 100,
One end of the purge passage 102 is connected. The other end of the purge passage 102 is connected to an intake manifold (hereinafter simply referred to as an intake manifold) 104 provided in the intake passage 70. The purge passage 102 is connected to the canister 100
This is a passage for flowing the fuel adsorbed to the intake passage 70 toward the intake passage 70.

In the middle of the purge passage 102, an electromagnetically driven purge VSV 106 is provided. Purge VSV
The valve 106 is normally kept closed, and is opened only during the ON time of the duty signal when the duty signal is supplied from the engine ECU 24.
The purge VSV 106 is opened and closed so that the flow rate of gas flowing through the purge passage 102 (hereinafter, referred to as a purge flow rate) is maintained at a predetermined value.

The canister 100 also has an air introduction hole 100c provided on the side opposite to the vapor introduction hole 100a and the fuel purge hole 100b. Canister 10
One end of the first gas passage 108 is connected to the zero air introduction hole 100c. The other end of the first gas passage 108 is connected to the gas chamber 66 of the fuel tank 60. In such a configuration, the gas chamber 66 and the intake manifold 104 are connected to the first gas passage 108, the canister 100, and the purge passage 1
02 is communicated.

The gas chamber 66 is provided with the second gas passage 11.
0 is connected to one end. The other end of the second gas passage 110 is connected to the purge passage 102 described above. In such a configuration, the gas chamber 66 and the intake manifold 104 are communicated with each other via the second gas passage 110 and the purge passage 102, bypassing the canister 100. The second
The gas passage 110 is referred to as a bypass passage 110. The bypass passage 110 has a capacity equal to that of the gas chamber 66 of the fuel tank 60.
It is designed to be considerably smaller than the volume of

An electromagnetically driven bypass VSV 112 is provided at the connection between the bypass passage 110 and the purge passage 102. The bypass VSV 112 is a valve that switches the communication path between the gas chamber 66 and the intake manifold 104 between the first gas passage 108 via the canister 100 and the bypass passage 110 bypassing the canister 100. The bypass VSV 112 is normally connected to the gas chamber 66 and the intake manifold 10.
4 is maintained so as to be communicated via the first gas passage 108, and the drive signal is supplied from the engine ECU 24 so that the gas chamber 66 and the intake manifold 104 are communicated via the bypass passage 110. This is a two-position solenoid valve that operates in the following manner.

At the end of the bypass passage 110 on the gas chamber 66 side, a tank internal pressure sensor 114 is provided. The tank internal pressure sensor 114 outputs a signal corresponding to the pressure in the bypass passage 110 (hereinafter, referred to as tank internal pressure P). The output signal of the tank internal pressure sensor 114 is
It is supplied to the CU 24. The engine ECU 24 detects the tank internal pressure P based on the output signal of the tank internal pressure sensor 114.

In the exhaust passage 120 of the internal combustion engine 40, O₂
A sensor 122 is provided. O ₂The sensor 122 is
According to the oxygen concentration in the exhaust gas flowing through the exhaust passage 120
Output the output signal. The oxygen concentration in the exhaust gas is
The air-fuel ratio of the air-fuel mixture supplied into the 40 cylinders becomes the ideal air-fuel ratio
Compared to fuel-rich,
Large when the air-fuel ratio is leaner than the ideal air-fuel ratio.
It will be good. O₂The sensor 122 detects that the air-fuel ratio is rich in fuel.
In some cases, a high signal of about 0.9 V is output, and the air-fuel ratio is
Outputs a low signal of about 0.1 V when fuel is lean
I do. O₂The output signal of the sensor 122 is
24. The engine ECU 24₂C
The air-fuel ratio becomes fuel rich based on the output signal of the sensor 122.
Whether it is fuel-lean or fuel-lean.
Set.

A crank angle sensor 124 and a water temperature sensor 126 are connected to the engine ECU 24. The crank angle sensor 124 outputs a reference signal every time the rotation angle of the crankshaft of the internal combustion engine 40 reaches a predetermined rotation angle. Further, the water temperature sensor 126 outputs a signal corresponding to the temperature of the cooling water for cooling the internal combustion engine 40. Output signal of crank angle sensor 124 and water temperature sensor 126
Are supplied to the engine ECU 24. The engine ECU 24 detects the engine speed NE based on the output signal of the crank angle sensor 124,
The temperature T of the cooling water based on the output signal of the water temperature sensor 126
HW is detected.

Next, the operation of the evaporative purge system of this embodiment will be described.

In the system of this embodiment, the evaporated fuel (vapor) generated in the fuel chamber 64 and the sub-tank 92 of the fuel tank 60 passes through the first vapor discharge passage 94 and the second vapor discharge passage 96 to the canister 100. Be guided.

During operation of the internal combustion engine 40, the intake passage 70
The downstream side of the throttle valve 74, that is, the intake manifold 104 is in a negative pressure state. In such a state, purge VS
When the V106 is opened, the air flows along the flow path of the air cleaner 72, the air introduction path 68, the gas chamber 66, the first gas passage 108, the canister 100, the purge passage 102, and the intake manifold 104. In this case, the canister 100
Is released from the activated carbon and purged together with air toward the intake manifold 104. Hereinafter, a mixture of fuel and air purged to the intake manifold 104 is referred to as “purge gas”, and a period during which the purge gas is purged toward the intake manifold 104 is referred to as “purging”.

The purge gas flowing from the fuel tank 60 into the intake manifold 104 is sucked into the cylinder of the internal combustion engine 40 together with the air flowing into the intake manifold 104 from the air cleaner 72 via the throttle valve 74. That is, the fuel adsorbed by the canister 100 is supplied to the internal combustion engine 40. Therefore, according to the system of the present embodiment, the vapor generated in the fuel tank 60 can be supplied to the internal combustion engine 40 as fuel without being released to the atmosphere.

When the purge gas is not flowing from the canister 100 to the intake manifold 104, the internal combustion engine 40
Of the fuel injection valve based on the intake air amount Ga such that the ratio (air-fuel ratio) between the amount of air taken into the cylinder and the amount of fuel injected from the fuel injection valve becomes a constant value (ideal air-fuel ratio). The fuel injection time TAU is set. In this case, by maintaining the air-fuel ratio in the vicinity of the ideal air-fuel ratio, good exhaust emission is secured in the internal combustion engine 40.

On the other hand, from the canister 100 to the intake manifold 10
When the purge gas flows to the canister 4, the canister 1
Fuel deviating from 00 causes an excess of fuel. Therefore, in such a case, if the fuel injection time TAU of the fuel injection valve is set based on the intake air amount Ga, the air-fuel ratio becomes fuel-rich. The fuel injection time TAU is feedback corrected so that the actual air-fuel ratio becomes the ideal air-fuel ratio. Therefore, even if the purge gas flows from the canister 100 to the intake manifold 104, the fuel injection time TAU is shortened by a time corresponding to the amount of fuel contained in the purge gas. Therefore, even when the purge gas flows from the canister 100 to the intake manifold 104, good exhaust emission can be ensured.

Incidentally, as described above, the evaporative purge system of the present embodiment does not discharge the vapor generated in the fuel tank 60 to the atmosphere, but uses the internal combustion engine 4 as fuel as fuel.
0 system. In this regard, the fuel tank 60
Alternatively, the intake passage 70 or the intake manifold 104 and the fuel tank 6
The air introduction passage 68 and the purge passage 1 connecting the
When a hole is formed in a flow path such as 02 (hereinafter, these are collectively referred to as an evaporative system), the function as an evaporative purge system cannot be secured. Therefore, in order for the system as in this embodiment to function properly, it is necessary to reliably determine whether or not a hole is formed in the evaporation system. Hereinafter, the determination as to whether or not a hole is formed in the evaporative system is referred to as evaporative system hole determination.

In this embodiment, when the execution condition of the evaporative hole determination is satisfied during the purge, the CCV 82 is closed. In this case, since the fresh air does not flow from the intake passage 70 to the gas chamber 66 through the air introduction passage 68, the pressure in the evaporation system is greatly reduced toward the negative pressure generated in the intake passage 70. When the pressure in the evaporation system is reduced to a predetermined negative pressure, the purge VSV 106 is closed to shut off the purge passage 102. In this case, both the CCV 82 and the purge VSV 106 are closed, so that the evaporative system is closed.

If no hole is formed in the evaporative system, the pressure in the evaporative system gradually increases toward the positive pressure side as the fuel present in the evaporative system evaporates after the evaporative system is closed. On the other hand, when a hole is formed in the evaporative system, the air in the evaporative system flows from the hole into the evaporative system, and the pressure in the evaporative system rapidly increases toward the atmospheric pressure. Therefore, by detecting the pressure in the evaporative system after the evaporative system is closed, it is possible to determine whether or not a hole is formed in the evaporative system.

However, during the process of introducing the negative pressure of the intake passage 70 into the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure in order to perform the evaporative system hole determination, the vehicle 2
0 becomes a high load state, etc.
4 may be greatly opened. Throttle valve 7
When the valve 4 is opened greatly, the negative pressure generated in the intake passage 70 downstream of the throttle valve 74 decreases. For this reason, even if the negative pressure in the intake passage 70 is introduced into the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure in order to perform the evaporative system hole determination, the negative pressure in the intake passage 70 is small. Can not introduce a large negative pressure into the evaporative system, it can take a lot of time to reach the predetermined value in the evaporative system, or can reach the predetermined value It may disappear.

On the other hand, in the system of this embodiment, when the negative pressure of the intake passage 70 is introduced into the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure in order to determine the evaporative system hole. In addition, the upper limit of the opening degree of the throttle valve 74 is changed to the valve closing side irrespective of the load state required in the vehicle 20. According to this method, since the throttle valve 74 is prevented from being largely opened, the negative pressure generated in the intake passage 70 can be maintained at a large state. The system of this embodiment has a first feature in that the upper limit of the opening of the throttle valve 74 is changed to the valve closing side as described above. Hereinafter, a first characteristic point of the system according to the present embodiment will be described.

FIG. 3 is a flowchart showing an example of a control routine executed by the engine ECU 24 in this embodiment to control the opening of the throttle valve 74. FIG.
Is a routine that is started each time the processing is completed. When the routine shown in FIG. 3 is started, first, the process of step 200 is executed.

In step 200, the hybrid ECU
Based on the signal supplied from 22, the processing for grasping the output required of the internal combustion engine 40 is executed.

In step 202, the above-mentioned step 200
In the required output W _E of the engine 40 which is grasped, from the relationship between the engine speed NE at the present time, the throttle opening being requested (hereinafter, the request called a throttle opening) the process of calculating the runs .

FIG. 4 is a diagram showing the upper limit of the throttle opening with respect to the engine speed NE. In FIG. 4, the maximum allowable upper limit (hereinafter referred to as the maximum upper limit) obtained as a result of considering the engine performance in the internal combustion engine 40 of the hybrid vehicle as in this embodiment is indicated by a broken line, and the vehicle 2
The upper limit allowed during normal running of 0 (hereinafter referred to as the normal upper limit) is indicated by a dashed line, and the upper limit allowed when a negative pressure is introduced into the evaporative system for performing evaporative system hole determination. The values (hereinafter, referred to as upper limit values at the time of determination) are indicated by solid lines, respectively.

As shown in FIG. 4, the upper limit of the throttle opening decreases in the order of the maximum upper limit, the normal upper limit, and the upper limit at the time of determination. In this embodiment, the normal upper limit is
The negative pressure in the intake passage 70 is set to, for example, about -50 mmHg, and the determination upper limit is set to a value such that the negative pressure in the intake passage 70 is, for example, about -100 mmHg.

In the routine shown in FIG.
4 is a diagram showing whether or not a power performance priority request has been made to prioritize the vehicle's power performance with respect to the required throttle opening calculated in step 202, that is, the required throttle opening is obtained from the relationship with the engine speed NE. It is determined whether or not the value is equal to or more than the maximum upper limit value indicated by the broken line in FIG. As a result, if the power performance priority request has not been made, that is, if the requested throttle opening is not equal to or greater than the maximum upper limit, the process of step 206 is executed next.

In step 206, it is determined whether or not the negative pressure of the intake passage 70 has been introduced into the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure in order to determine the evaporative system hole. As a result, if a negative determination is made,
Since it is not necessary to reduce the pressure in the evaporation system to a predetermined negative pressure, it is not necessary to increase the negative pressure in the intake passage 70.
Therefore, if such a determination is made, then step 2
08 is executed. On the other hand, if an affirmative determination is made, it is necessary to greatly reduce the pressure in the evaporative system to a predetermined negative pressure, so it is effective to ensure that the negative pressure in the intake passage 70 is large. Therefore, when such a determination is made, the process of step 210 is executed next.

In step 208, a process for calculating a throttle opening (hereinafter referred to as a target throttle opening) for actually opening the throttle valve 74 is performed using the normal upper limit value indicated by the dashed line in FIG. Is done. In particular,
The required throttle opening calculated in step 202 is
If it exceeds the normal upper limit obtained from the relationship with the engine speed NE, the normal upper limit is calculated as the target throttle opening, whereas if it does not exceed the normal upper limit, the required throttle opening is calculated as the target throttle opening.

In step 210, a process of calculating the target throttle opening using the upper limit value at the time of determination shown by the solid line in FIG. 4 is executed. Specifically, similarly to the processing in step 208, when the required throttle opening calculated in step 202 exceeds the upper limit for determination obtained from the relationship with the engine speed NE, the upper limit for determination is set. , On the other hand,
If it does not exceed the upper limit at the time of determination, the required throttle opening is calculated as the target throttle opening.

On the other hand, if the power performance priority request for the throttle valve 74 has been made in step 204, the request is given priority over the evaporative system hole determination and the vehicle 20
It is appropriate to respect the crew's will. Therefore, when the power performance priority request is made in step 204, the process of step 212 is executed next.

In step 212, a process of calculating the maximum upper limit obtained from the relationship with the engine speed NE as the target throttle opening is executed.

Step 208, 210, or 212
Is completed, the process of step 214 is executed.

In step 214, step 20
A process of supplying a drive signal to the throttle actuator 76 is executed so that the throttle valve 74 is opened at the target throttle opening calculated at 8, 210, or 212. When the processing of step 214 is completed,
This routine ends.

According to the above processing, when the negative pressure of the intake passage 70 is introduced into the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure in order to determine the evaporative system hole, the throttle is The upper limit of the opening of the valve 74 can be changed to the valve closing side. When the upper limit value of the throttle opening is changed to the valve closing side, it is avoided that the throttle valve 74 is opened unduly large. In this case, the intake passage 70
Is maintained in a larger state than when the upper limit of the throttle opening is not changed to the valve closing side.

When the negative pressure in the intake passage 70 is maintained at a high level, the pressure in the evaporation system is easily reduced. Therefore,
According to the system of the present embodiment, when the negative pressure of the intake passage 70 is introduced into the evaporative system for performing the evaporative system hole determination,
The pressure in the evaporation system can be promptly and reliably reduced to a predetermined negative pressure. Therefore, according to the system of the present embodiment, it is possible to execute the evaporative hole determination in a short period of time.

In the routine shown in FIG. 3, if it is determined in step 204 that a power performance priority request has been made for the requested throttle opening, then,
The throttle valve 74 is in a state equivalent to full opening. When the throttle valve 74 is fully opened, the negative pressure generated in the intake passage 70 becomes small, and it becomes difficult to reduce the pressure in the evaporation system to a predetermined negative pressure. In this case, it takes a long time to perform the evaporative hole determination.
The period in which the fuel adsorbed at 00 may be purged into the intake passage 70 may be shortened, or it may be impossible to perform the evaporative hole determination itself, and erroneous determination may occur in the determination result of the evaporative hole determination. There is.

Therefore, in the present embodiment, when an affirmative determination is made in step 204 in the routine shown in FIG. 3, a process for stopping the execution of the evaporative hole determination is executed in advance. In this case, the above-described inconvenience can be avoided, and erroneous determination can be reliably prevented from occurring in the determination result of the evaporation system hole determination.

By the way, as described above, the throttle valve 7
When the upper limit value of the opening degree of the valve 4 is changed to the valve closing side, the amount of intake air decreases, so that the output generated in the internal combustion engine 40 decreases. In this case, in the vehicle 20, the driving force for driving is reduced.

On the other hand, in this embodiment, the vehicle 2
Reference numeral 0 denotes a hybrid vehicle that generates power by appropriately combining the internal combustion engine 40 and the electric motor 42 as described above. In such a vehicle 20, even if the output generated in the internal combustion engine 40 decreases, the output corresponding to the decrease is output to the electric motor 4.
2, the driving force of the vehicle 20 can be prevented from decreasing. Therefore, in the system of the present embodiment, the upper limit of the opening degree of the throttle valve 74 is changed to the valve closing side so that the internal combustion engine 4
When the output of 0 is reduced, the output generated by the electric motor 42 is increased by the reduced output. The system of this embodiment has a second feature in this point. Hereinafter, the second characteristic point will be described.

FIG. 5 shows the engine E in the present embodiment in order to calculate the output of the internal combustion engine 40 reduced by changing the upper limit of the opening of the throttle valve 74 to the valve closing side.
4 shows a flowchart of an example of a control routine executed by the CU 24. The routine shown in FIG. 5 is a routine that is started each time the processing is completed. When the routine shown in FIG. 5 is started, first, the process of step 240 is executed.

In step 240, similarly to the processing in step 206 in the routine shown in FIG. 3, the intake passage 70 is provided in the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure in order to determine the evaporative system hole. It is determined whether or not the negative pressure is introduced. As a result, if a negative determination is made, the current routine is terminated without any further processing. On the other hand, if an affirmative determination is made, then the process of step 242 is performed.

In step 242, the above step 210
Throttle opening and engine speed NE calculated by
Based on its target throttle opening output to be generated in the internal combustion engine 40 when the throttle valve 74 is opened (hereinafter, referred to as generator output) processing of calculating the W ₀ is executed.

At step 244, the hybrid ECU
The difference between the required output W _E of the internal combustion engine 40 supplied from the internal combustion engine 22 and the generated output W ₀ calculated in step 242 is
A process of calculating an output that the internal combustion engine 40 cannot generate (hereinafter, referred to as an insufficient output) ΔW is executed.

In step 246, the above step 244
In order to notify the hybrid ECU 22 of the insufficient output ΔW calculated in the above, a process of transmitting a signal corresponding to the insufficient output ΔW to the hybrid ECU 22 is executed. When the process of step 246 ends, the current routine ends.

According to the above processing, the throttle valve 7
The opening degree of the internal combustion engine 40 is changed to the valve closing side.
Is reduced, the value of the reduced output can be notified to the hybrid ECU 22.

FIG. 6 shows a flowchart of an example of a control routine executed by the hybrid ECU 22 in this embodiment to compensate for the decrease in the output of the internal combustion engine 40.
The routine shown in FIG. 6 is a routine that is started each time the processing is completed. When the routine shown in FIG. 6 is started, first, the process of step 280 is executed.

In step 280, the engine ECU 24
It is determined whether or not a signal corresponding to the shortage output ΔW has been received. As a result, if a signal corresponding to the shortage output ΔW has not been received, the current routine is terminated without any further processing. On the other hand, the insufficient output ΔW
Is received, the process of step 282 is executed.

FIG. 7 is a diagram showing a map representing the relationship between the remaining capacity of the battery 50 and the output that can be generated by the electric motor 42 (hereinafter, referred to as a possible output).

At step 282, the above-mentioned step 280 is executed.
The insufficient output .DELTA.W received at (1) is a possible output f (remaining capacity-.alpha.) Obtained by referring to the map shown in FIG.
It is determined whether or not it is smaller than. When ΔW <f (remaining capacity−α) is not established, it can be determined that the insufficient output ΔW cannot be generated even in the electric motor 42 because the remaining capacity of the battery 50 is small. Therefore, if such a determination is made, the current routine ends. On the other hand, if it is determined that ΔW <f (remaining capacity−α) holds, the process of step 284 is next performed.

[0087] At step 284, the output W _M to be generated by the electric motor 42, the required output W of the electric motor 42 computed at the time of calculating the driving force required for the vehicle 20
A process of adding the above-mentioned insufficient output ΔW to _M to obtain a value obtained by the addition is executed. After the process of step 284 is performed, the electric motor 42 thereafter generates a large output so as to compensate for the insufficient output ΔW that is not generated in the internal combustion engine 40. When the process of step 284 is completed,
This routine is ended.

According to the above processing, when the output generated in the internal combustion engine 40 decreases, the output of the electric motor 42 can be increased by the decrease. For this reason, according to this embodiment, the output of the internal combustion engine 40 decreases due to the upper limit of the opening of the throttle valve 74 being changed to the valve closing side in order to quickly reduce the pressure in the evaporation system. In this case, it is possible to prevent the driving force of the vehicle 20 from decreasing. That is, according to the system of the present embodiment, it is possible to secure a large negative pressure in the intake passage 70 and reduce the pressure in the evaporation system quickly and surely without lowering the driving force of the vehicle 20. It has become.

Next, a second embodiment of the present invention will be described with reference to FIGS.

Incidentally, the negative pressure generated in the intake passage 70 is
Even if the opening of the throttle valve 74 is the same, it varies according to the atmospheric pressure. That is, even if the opening degree of the throttle valve 74 is the same, the negative pressure generated in the intake passage 70 decreases as the atmospheric pressure decreases. For this reason, as the atmospheric pressure decreases, the pressure in the evaporation system becomes more difficult to reduce.

Therefore, in the system of this embodiment,
As the atmospheric pressure decreases, the upper limit value of the throttle opening is further set to the valve closing side. According to such an approach,
Even when the atmospheric pressure is reduced, it is avoided that the negative pressure generated in the intake passage 70 decreases. Therefore, according to the system of the present embodiment, it is possible to maintain the negative pressure generated in the intake passage 70 in a large state regardless of the atmospheric pressure.
Hereinafter, features of the system according to the present embodiment will be described.

FIG. 8 is a flowchart showing an example of a control routine executed by the engine ECU 24 in this embodiment to control the opening of the throttle valve 74. still,
8, steps that execute the same processing as the steps shown in FIG. 3 are given the same reference numerals, and descriptions thereof will be omitted. That is, after a positive determination is made in step 206, the process of step 300 is executed next.

In step 300, a process for detecting the atmospheric pressure atm is executed. Specifically, in the present embodiment, the reference intake air amount determined from the relationship between the throttle opening degree TA and the engine speed NE is compared with the actual intake air amount Ga detected using the air flow meter 80. To detect the atmospheric pressure atm. Note that a sensor for actually detecting the atmospheric pressure may be provided, and the atmospheric pressure atm may be detected based on the output signal.

FIG. 9 is a diagram showing the upper limit value for determining the throttle opening determined from the relationship between the engine speed NE and the atmospheric pressure atm. As shown in FIG. 9, even when the engine speed NE is the same, the lower the atmospheric pressure atm, the smaller the upper limit value at the time of determination.

In step 302, a process for calculating the target throttle opening is executed using the upper limit value for judgment obtained by referring to the map shown in FIG. When the processing of step 302 is completed, step 2
At 14, the throttle actuator 7 is opened so that the throttle valve 74 is opened to the target throttle opening.
After the drive signal is supplied to 6, the current routine ends.

According to the above processing, when the negative pressure of the intake passage 70 is introduced into the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure in order to perform the evaporative system hole determination,
As the atmospheric pressure decreases, the upper limit of the opening of the throttle valve 74 can be set to the valve closing side. For this reason, according to the present embodiment, even when the atmospheric pressure decreases, it is possible to prevent the negative pressure generated in the intake passage 70 from decreasing.

If the negative pressure in the intake passage 70 is not reduced, that is, if the negative pressure in the intake passage 70 is maintained at a large state, the pressure in the evaporative system is easily reduced. Therefore, according to the system of the present embodiment, it is possible to quickly and surely reduce the pressure in the evaporation system to a predetermined negative pressure regardless of the atmospheric pressure. For this reason, according to the system of the present embodiment, it is possible to execute the evaporative hole determination in a short period of time regardless of the atmospheric pressure.

Next, a third embodiment of the present invention will be described with reference to FIG.

In the first embodiment described above, when a power performance priority request is made to the throttle valve 74, the throttle valve 74 is brought into a fully opened state to satisfy the request, and the execution of the evaporative hole determination is stopped. You. However, when such a state is realized, the gas adsorbed on the canister 100 cannot be purged toward the intake passage 70 because the gas does not effectively flow through the evaporative system, and the execution frequency of the evaporative system hole determination decreases. Would. On the other hand, the system of the present embodiment has the throttle valve 7
4, even when the power performance priority request is made, while the evaporative system hole determination is being performed, the above-described inconvenience is prevented by preventing the throttle valve 74 from being in the fully opened state. I have.

FIG. 10 shows a flowchart of an example of a control routine executed by the engine ECU 24 in this embodiment to control the opening of the throttle valve 74.
In FIG. 10, steps that execute the same processes as the steps shown in FIGS. 3 and 8 are denoted by the same reference numerals, and description thereof will be omitted. That is, step 2
After the end of the process of step S02, the process of step 340 is executed next.

In step 340, similar to the processing in step 206 in the routine shown in FIG. 3, the intake passage 70 is provided in the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure in order to determine the evaporative system hole. It is determined whether or not the negative pressure is introduced. As a result, if an affirmative determination is made, then the processing of step 300 and subsequent steps is executed.
On the other hand, if a negative determination is made, then step 342
Is performed.

In step 342, it is determined whether or not a power performance priority request has been made for the throttle valve 74, as in the process of step 204 in the routine shown in FIG. As a result, if the power performance priority request has not been made, the processing after step 208 is executed next. On the other hand, if the power performance priority request has been made, the processing of step 212 and subsequent steps is executed next.

According to the above processing, the throttle valve 7
Even if the power performance priority request is made for No. 4,
While a negative pressure is being introduced into the evaporative system for evaporative system hole determination, the throttle valve 74 does not enter a fully opened state, and execution of the evaporative system hole determination is not stopped. For this reason, according to the present embodiment, after the execution condition of the evaporation system hole determination is satisfied, the determination can be completed promptly, and as a result, the period during which the fuel adsorbed by the canister 100 can be purged to the intake passage 70 is reduced. It can be sufficiently secured. Further, according to the present embodiment, it is possible to avoid a decrease in the execution frequency of the evaporation hole determination.

If the throttle valve 74 is not fully opened even though the power performance priority request is made for the throttle valve 74, the intake air amount to the internal combustion engine 40 decreases by the difference, and Institution 4
The output of 0 decreases. Therefore, in the present embodiment, the output of the electric motor 42 may be increased by the reduced output of the internal combustion engine 40. According to this method, it is possible to secure a desired driving force in the vehicle 20 even when the throttle performance of the throttle valve 74 does not correspond to the fully opened state despite the request for the priority of the power performance.

In the first to third embodiments,
The engine ECU 24 performs the evaporative hole determination to thereby determine the “state determination means”.
However, when the negative pressure of the intake passage 70 is introduced into the evaporative system so that the pressure in the evaporative system reaches a predetermined negative pressure for performing the evaporative system hole determination, the upper limit value of the opening degree of the throttle valve 74 is determined. Is changed from the normal upper limit value to the determination upper limit value, thereby realizing the "opening upper limit value changing means" recited in the claims.

In the first to third embodiments, the electric motor 42 corresponds to the "power source other than the internal combustion engine" described in the appended claims, and the hybrid ECU 22 corresponds to FIG. Step 2 in the indicated routine
By executing the process of 84, the "output changing means" described in the claims is realized.

Next, a fourth embodiment of the present invention will be described with reference to FIG.

When the pressure in the evaporative system reaches a predetermined negative pressure in order to perform the evaporative system hole judgment, the evaporative system is controlled based on the elapsed time after the introduction of the negative pressure into the evaporative system. It may be determined whether or not the pressure has reached a predetermined negative pressure, that is, whether or not the introduction of the negative pressure into the evaporation system has been completed. However, if the negative pressure in the intake passage 70 becomes small, a situation may occur in which the negative pressure cannot be effectively introduced into the evaporative system. May not reach the predetermined negative pressure. For this reason, in the above-described method, if there is a time when the negative pressure in the intake passage 70 decreases after the introduction of the negative pressure into the evaporative system, the pressure in the evaporative system is reduced to a predetermined value when a predetermined time has elapsed. Although the negative pressure has not reached, there is a possibility that it is erroneously determined that the negative pressure has been reached.

Therefore, the system according to the present embodiment, when the negative pressure in the intake passage 70 becomes small after the introduction of the negative pressure to the evaporative system for performing the evaporative system hole judgment, the elapsed time only for that period. It is decided to suspend the accumulation. Hereinafter, features of the present embodiment will be described.

FIG. 11 shows the engine ECU 24 according to the present embodiment in order to determine whether or not to execute the evaporative system hole judgment.
3 shows a flowchart of an example of a control routine executed by the computer. The routine shown in FIG. 11 is a routine that is started each time the processing is completed. When the routine shown in FIG. 11 is started, first, the process of step 400 is executed.

In step 400, it is determined whether or not a condition for performing the evaporative hole determination is satisfied. The above condition is satisfied, for example, when the start of the internal combustion engine 40 is completed and the purge gas is purged toward the intake passage 70. As a result, if the above condition is not satisfied,
Thereafter, the current routine ends without any processing being performed. On the other hand, if the above condition is satisfied, the process of step 402 is executed next.

In step 402, it is determined whether or not the pressure in the intake passage 70 estimated based on the load of the internal combustion engine 40 (hereinafter referred to as the intake pressure PM) is lower than a predetermined value A, that is, whether the pressure in the intake passage 70 is negative. It is determined whether the pressure exceeds a predetermined value A. When PM <A is satisfied, it can be determined that a large negative pressure is generated in the intake passage 70, and it is possible to guide a large negative pressure to the evaporation system. Therefore, PM <A
Is satisfied, the process of step 404 is executed next. On the other hand, when PM <A is not satisfied, it can be determined that the negative pressure in the intake passage 70 is small and the negative pressure cannot be effectively introduced into the evaporative system. Therefore, PM <
If it is determined that A does not hold, the process of step 404 is skipped, and the process of step 406 is executed.

In step 404, a process for accumulating the time T during which the intake pressure PM is small after the condition for performing the evaporative hole determination is satisfied is executed.

In step 406, step 404 is performed.
It is determined whether or not the accumulated time T is equal to or longer than the predetermined time B. When T ≧ B is not satisfied, it can be determined that a large negative pressure is not confined in the entire evaporation system. If the evaporative hole determination is performed in such a state, an erroneous determination may occur in the determination result. Therefore, T ≧ B
Is not established, the current routine is terminated. On the other hand, when T ≧ B is satisfied, it can be determined that a large negative pressure is confined in the entire evaporative system, and it is appropriate to perform the evaporative system hole determination. Therefore, when it is determined that T ≧ B is satisfied, the process of step 408 is executed next.

In step 408, a process for performing the evaporative hole determination is executed. When the process of step 408 is performed, thereafter, after the pressure of the evaporative system reaches a predetermined negative pressure, the system is closed, and a hole is opened in the evaporative system based on a change in pressure in the evaporative system thereafter. Is determined. When the process of step 408 ends, the current routine ends.

According to the above-described processing, when the negative pressure in the intake passage 70 becomes small after the introduction of the negative pressure to the evaporative system for performing the evaporative system hole determination, the evaporative system The accumulation of the elapsed time for determining whether or not the determination can be performed can be interrupted. For this reason, according to the present embodiment, after the start of the introduction of the negative pressure, the pressure in the evaporative system has reached, even though the negative pressure required to accurately perform the evaporative system hole determination has not been reached. An erroneous determination can be prevented. That is, it is possible to accurately determine whether or not the pressure in the evaporation system has reached a predetermined negative pressure. Therefore, according to the system of the present embodiment, it is possible to accurately determine whether or not a hole is formed in the evaporation system.

In the fourth embodiment, the engine ECU 24 controls the CCV during the purging operation so that the pressure in the evaporative system reaches a predetermined negative pressure for evaporative system hole determination.
By closing the valve 82, the “negative pressure introducing means” described in the claims executes the processing of step 404, and the “time calculating means” described in the claims executes the processing of the step By executing the processing of 406 and 408, the “determination means” described in the claims is realized.

Incidentally, in the above embodiment, FIG.
In the routine shown in FIG.
If it is determined that M exceeds the predetermined value A, the time T
Is maintained at the previous value without accumulation. However, when the intake pressure PM exceeds the predetermined value A, not only the pressure in the evaporative system cannot be effectively reduced, but also the pressure in the evaporative system may be increased. For this reason, simply maintaining the time T at the previous value when the intake pressure PM exceeds the predetermined value A accurately determines whether or not the entire pressure in the evaporation system has reached the predetermined negative pressure. Can not do. Therefore, the above step 40
After it is determined in 2 that the intake pressure PM exceeds the predetermined value A, the time T may be subtracted or reset. In this case, the negative pressure introduction time for performing the evaporative system hole determination becomes substantially longer, so that the pressure in the evaporative system can reliably reach a predetermined negative pressure.

Further, in the above embodiment, the time T during which the intake pressure PM exceeds the predetermined value A after the execution condition of the evaporative hole determination is satisfied, and the time T is equal to or longer than the predetermined time B Whether or not to execute the evaporative hole determination is determined based on whether or not the above condition is satisfied. However, after the execution condition of the evaporative hole determination is satisfied, if the intake pressure PM exceeds a predetermined value A, The predetermined time B is extended by that period, and the time after the execution condition of the evaporative hole determination is satisfied is the predetermined time B.
The above determination may be made based on whether or not the above is true. In this case, the engine ECU 24 extends the predetermined time B for a period during which the intake pressure PM exceeds the predetermined value A after the execution condition of the evaporative system hole determination is satisfied. Extension means "is realized.

Next, a fifth embodiment of the present invention will be described with reference to FIG.

By the way, when the pressure in the evaporation system reaches a predetermined negative pressure in order to make a determination on the evaporation system hole, based on the integrated value of the purge flow rate after the introduction of the negative pressure into the evaporation system is started. It may be determined whether or not the pressure in the evaporation system has reached a predetermined negative pressure, that is, whether or not the introduction of the negative pressure into the evaporation system has been completed. However, even in such a method, if there is a time when the negative pressure in the intake passage 70 becomes small after the introduction of the negative pressure into the evaporative system, the internal pressure of the evaporative system is reduced when the integrated value of the purge flow rate reaches a predetermined amount. May not be determined to have reached the predetermined negative pressure even though the pressure has not reached the predetermined negative pressure.

Therefore, the system according to the present embodiment, when the negative pressure in the intake passage 70 becomes small after the introduction of the negative pressure into the evaporative system to perform the evaporative system hole judgment, determines the integrated value of the purge flow rate. Is to be cleared. Hereinafter, features of the present embodiment will be described.

FIG. 12 shows the engine ECU 24 according to this embodiment in order to determine whether or not to execute the evaporative system hole judgment.
3 shows a flowchart of an example of a control routine executed by the computer. In FIG. 12, steps that execute the same processing as the steps shown in FIG. 11 are denoted by the same reference numerals, and description thereof will be omitted. That is, step 40
If an affirmative determination is made in step 2, then step 4
The process of step S <b> 40 is performed, and if a negative determination is made, the process of step 442 is next performed.

At step 440, step 400
After the conditions of 402 and 402 are satisfied, a process of integrating the purge flow rate estimated based on the relationship between the intake air amount Ga and the purge rate indicating the volume ratio of the purge flow amount to the intake air amount Ga is executed. Hereinafter, this integrated value is referred to as an integrated value TOTAL.

In step 442, step 440 is performed.
A process for clearing the integrated value TOTAL of the purge flow rate calculated in the step is executed. After the process of step 442 is performed, the evaporative hole determination is not performed thereafter.

In step 444, it is determined whether the integrated value TOTAL of the purge flow rate is equal to or greater than a predetermined value C.
When TOTAL ≧ C is not satisfied, it can be determined that the gas in the evaporation system has not been sufficiently purged into the intake passage 70. Therefore, if such a determination is made, the current routine ends. On the other hand, when TOTAL ≧ C is satisfied, it can be determined that the gas in the evaporation system has been sufficiently purged into the intake passage 70. Therefore, when such a determination is made, the process of performing the evaporation system hole determination is then performed in step 408, and then the current routine is terminated.

According to the above-described processing, when the negative pressure in the intake passage 70 becomes small after the introduction of the negative pressure to the evaporative system for performing the evaporative system hole determination, the execution of the evaporative system hole determination is performed. It is possible to clear the integrated value of the purge flow rate for judging the availability. For this reason, according to the system of the present embodiment, as in the case of the above-described fourth embodiment, after the introduction of the negative pressure, the pressure in the evaporative system is reduced by the negative pressure necessary for accurately performing the evaporative system hole determination. Can be prevented from being erroneously determined to have arrived even though it has not arrived. As a result,
It is possible to accurately determine whether or not a hole is formed in the evaporation system.

In the fifth embodiment, the "reset means" described in the claims is realized by the engine ECU 24 executing the process of step 442.

In the first to fifth embodiments, the fuel tank 60 having the bladder film 62 is used. However, the present invention is not limited to this. It is also possible to apply to a fuel tank.

[0130]

As described above, according to the first aspect of the present invention, when a negative pressure is introduced into the evaporative fuel treatment mechanism, the internal pressure of the evaporative fuel treatment mechanism can be rapidly reduced.

According to the second aspect of the invention, the internal pressure of the evaporated fuel processing mechanism can be rapidly reduced regardless of the atmospheric pressure.

According to the third aspect of the present invention, even when the opening of the throttle valve is changed to the valve closing side to quickly reduce the internal pressure of the evaporative fuel treatment mechanism, the driving force of the vehicle is prevented from being reduced. Claims 4 to 7 which can be prevented.
According to the described invention, it is possible to accurately determine whether or not the internal pressure of the evaporated fuel processing mechanism has reached the predetermined negative pressure.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a drive mechanism of a vehicle equipped with an evaporative purge system diagnostic device according to an embodiment of the present invention.

FIG. 2 is a system configuration diagram of an evaporative purge system of the present embodiment.

FIG. 3 is a flowchart of an example of a control routine executed by an engine ECU in the embodiment.

FIG. 4 is a diagram illustrating an upper limit value of an opening degree of a throttle valve with respect to an engine speed NE.

FIG. 5 is a flowchart of an example of a control routine executed by an engine ECU to calculate an output of the internal combustion engine reduced by changing the upper limit value of the opening of the throttle valve to the valve closing side in the present embodiment. is there.

FIG. 6 is a flowchart of an example of a control routine executed by a hybrid ECU to compensate for a decrease in the output of the internal combustion engine in the embodiment.

FIG. 7 is a diagram showing a map representing a relationship between a remaining capacity of a battery and an output that can be generated by an electric motor.

FIG. 8 is a flowchart illustrating an example of a control routine executed by an engine ECU according to a second embodiment of the present invention.

FIG. 9 is a diagram showing an upper limit value at the time of determination of a throttle opening determined from a relationship between an engine speed NE and an atmospheric pressure atm.

FIG. 10 shows an engine ECU according to a third embodiment of the present invention.
4 is a flowchart of an example of a control routine executed by the control unit.

FIG. 11 shows an engine ECU according to a fourth embodiment of the present invention.
4 is a flowchart of an example of a control routine executed by the control unit.

FIG. 12 shows an engine ECU according to a fifth embodiment of the present invention.
4 is a flowchart of an example of a control routine executed by the control unit.

[Explanation of symbols]

22 Electronic control unit for hybrid (hybrid ECU) 24 Electronic control unit for engine (engine ECU) 26 Electronic control unit for motor (motor ECU) 40 Internal combustion engine 42 Electric motor 60 Fuel tank 70 Intake passage 74 Throttle valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02M 25/08 F02M 25/08 Z F term (Reference) 3G044 AA10 BA24 DA00 DA09 EA07 EA08 EA17 EA19 EA32 EA36 EA44 EA53 EA55 EA61 FA04 FA05 FA06 FA08 FA20 FA29 FA32 FA39 3G065 AA00 BA06 CA00 DA04 FA02 FA11 GA10 GA11 GA26 GA42 KA36 3G093 AA07 AA16 AB00 BA00 DA01 DA03 DA06 DA08 DB05 DB07 DB08 DB23 EA09 EB00 EC02 FA04 FA11 FA14 FB01 LC03 NA08 NC08 ND01 ND41 NE03 NE08 NE18 NE23 PA07Z PA09Z PA11Z PB00Z PB09A PB09B PB09Z PE01Z PF01Z PF03Z

Claims (7)

[Claims] An evaporative fuel processing mechanism for adsorbing evaporative fuel generated in a fuel tank and purging the adsorbed evaporative fuel toward the intake passage by utilizing a negative pressure generated in the intake passage of the internal combustion engine; After the introduction of the negative pressure of the intake passage to the evaporative fuel processing mechanism is started, the state of the evaporative fuel processing mechanism is changed based on the internal pressure after the internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure. An evaporative purge system diagnostic device comprising: a determination unit configured to determine an upper limit value of an opening degree of a throttle valve provided in the intake passage when the determination is performed by the state determination unit. A diagnostic apparatus for an evaporative purge system, comprising: an opening upper limit value changing unit that changes to a valve closing side as compared with a case where the determination is not performed by the unit. 2. The evaporative purge system diagnostic apparatus according to claim 1, wherein the opening upper limit changing unit changes an upper limit of the opening of the throttle valve in accordance with an atmospheric pressure. Diagnostic device for purge system. 3. A control device for a vehicle equipped with the diagnosis apparatus for an evaporative purge system according to claim 1 or 2, wherein the vehicle is a hybrid vehicle having an internal combustion engine and a power source other than the internal combustion engine. Also, when the output of the internal combustion engine is reduced by changing the upper limit of the opening of the throttle valve to the valve closing side by the opening upper limit changing means, the power other than the internal combustion engine is reduced by the reduced output. 3. A control device for a vehicle equipped with a diagnostic device for an evaporative purge system according to claim 1, further comprising an output changing means for increasing an output of the power source. 4. An evaporative fuel treatment mechanism for adsorbing evaporative fuel generated in a fuel tank and purging the adsorbed evaporative fuel toward the intake passage by utilizing a negative pressure generated in the intake passage of the internal combustion engine. Negative pressure introducing means for introducing a negative pressure generated in the intake passage to the evaporative fuel processing mechanism so as to reach an internal pressure of the evaporative fuel processing mechanism to a predetermined negative pressure, the diagnostic apparatus for an evaporative purge system comprising: After the introduction of the negative pressure by the negative pressure introduction unit is started, a time calculation unit that accumulates a time when the pressure generated in the intake passage is less than a predetermined value, and an accumulation time accumulated by the time calculation unit is a predetermined time. Determining means for determining whether or not the internal pressure of the evaporative fuel processing mechanism has reached the predetermined negative pressure based on whether or not a time has been reached; and a diagnostic device for an evaporative purge system, comprising: 5. The diagnostic apparatus for an evaporative purge system according to claim 4, wherein the time calculating unit is configured to control the pressure generated in the intake passage to be equal to or more than a predetermined value after the introduction of the negative pressure by the negative pressure introduction unit is started. The diagnostic device for an evaporative purge system, wherein the cumulative time is subtracted or reset when the following condition is satisfied. 6. An evaporative fuel processing mechanism for adsorbing evaporative fuel generated in a fuel tank and purging the adsorbed evaporative fuel toward the intake passage by using a negative pressure generated in the intake passage of the internal combustion engine. Negative pressure introducing means for introducing a negative pressure generated in the intake passage to the evaporative fuel processing mechanism so that the internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure, and introduction of the negative pressure by the negative pressure introducing means is started. Determining means for determining whether or not the internal pressure of the evaporative fuel treatment mechanism has reached the predetermined negative pressure based on whether or not the time after the predetermined time has reached a predetermined time. And after the introduction of the negative pressure by the negative pressure introducing means is started,
When the pressure generated in the intake passage becomes a predetermined value or more,
A diagnostic device for an evaporative purge system, comprising a time extending means for extending the predetermined time. 7. An evaporative fuel processing mechanism for adsorbing evaporative fuel generated in a fuel tank and purging the adsorbed evaporative fuel toward the intake passage using a negative pressure generated in the intake passage of the internal combustion engine; Negative pressure introducing means for introducing a negative pressure generated in the intake passage to the evaporative fuel processing mechanism so that the internal pressure of the evaporative fuel processing mechanism reaches a predetermined negative pressure, and introduction of the negative pressure by the negative pressure introducing means is started. Whether the internal pressure of the evaporative fuel treatment mechanism has reached the predetermined negative pressure, based on whether or not the integrated value of the flow rate of the gas flowing from the evaporative fuel treatment mechanism to the intake passage after the elapse of the gas has reached a predetermined value. And a determination unit for determining whether or not the negative pressure is introduced by the negative pressure introduction unit after the introduction of the negative pressure is started.
When the pressure generated in the intake passage becomes a predetermined value or more,
A diagnostic device for an evaporative purge system, comprising: reset means for resetting the integrated value.