JP2013241855A - Evaporated fuel processing device of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporated fuel processing device of a vehicle capable of improving heating efficiency in a canister while effectively using electric energy collected by a regenerative means.SOLUTION: An evaporated fuel processing device includes a canister 30 for adsorbing evaporated fuel generated in a fuel tank 20, a purge valve 36 arranged in a purge passage 34 for communicating the canister 30 with an intake passage 12, a heater 40 for heating the canister 30, an ECU 60 for controlling the purge valve 36 and the heater 40, a vehicle speed sensor 53 and an accelerator opening sensor 55 for detecting a traveling state of the vehicle, and an alternator 66 for collecting kinetic energy of the vehicle as the electric energy. The ECU 60 controls the purge valve 36 so as to stop a purge when in a decelerating travel state, and operates the heater 40 by using the electric energy collected by the alternator 66.

Description

  The present invention relates to a fuel vapor processing apparatus for a vehicle.

  Conventionally, in a hybrid vehicle equipped with an engine (internal combustion engine) and an electric motor as a driving source for traveling, regenerative braking is performed to cause the motor to function as a generator during deceleration traveling, that is, during deceleration, and the electric motor is driven by the regenerative power By charging the capacitor, the kinetic energy of the vehicle body is recovered as electric energy, and when the capacitor cannot be charged, regenerative power is supplied to a heater that heats the canister (see, for example, Patent Document 1). .

JP 11-343890 A

  According to the conventional example (see Patent Document 1), the purge may be executed and the heater may be activated during deceleration. Then, since the heat of the heater is taken away by the purge air flowing through the canister, the heating efficiency of the canister is deteriorated. In addition, when the capacitor cannot be charged (fully charged), the regenerative power (electric energy) generated by the motor during deceleration is supplied to the heater, but the heat of the heater is taken away by the purge air. Electricity cannot be used effectively.

  The problem to be solved by the present invention is to provide an evaporative fuel processing apparatus for a vehicle that can improve the heating efficiency of the canister while effectively using the electric energy recovered by the regenerative means.

The above-mentioned problem can be solved by a fuel vapor processing apparatus for a vehicle having the structure described in the claims.
According to the evaporative fuel processing apparatus for a vehicle according to claim 1, the canister for adsorbing the evaporative fuel generated in the fuel tank mounted on the vehicle, and the purge passage for communicating the canister and the intake passage of the engine are provided. , Purge means for executing and stopping purge for evaporating fuel adsorbed by the canister to the engine, heating means for heating the canister, control means for controlling the purge means and the heating means, and the running state of the vehicle A traveling state detecting means for detecting and a regenerating means for recovering kinetic energy of the vehicle as electric energy are provided, and the control means stops the purge when the traveling state detected by the traveling state detecting means is a decelerating traveling state. Control the purge means and operate the heating means using the electrical energy recovered by the regenerative means. That.
According to this configuration, the purge is stopped and the heating means is operated using the electrical energy recovered by the regenerative means while the vehicle is running at a reduced speed. For this reason, it is possible to prevent the heat of the heating means from being taken away by the purge air. In this state, the canister can be heated by operating the heating means using the electric energy generated by the regenerative means. Therefore, it is possible to improve the heating efficiency of the canister while effectively using the electric energy collected by the regenerative means.

  According to the fuel vapor processing apparatus for a vehicle described in claim 2, the power generation amount control means for controlling the power generation amount generated by the regeneration means is provided, and the power generation amount control means regenerates when the heating means is operated in the deceleration traveling state. Increase the power generation of the means. Therefore, the heating efficiency of the canister can be improved by increasing the power generation amount of the regenerative unit when the heating unit is operated in the deceleration traveling state. Moreover, since the load torque of the regeneration means with respect to an internal combustion engine increases with the increase in the amount of power generated by the regeneration means, it can contribute to braking of the vehicle.

  According to the fuel vapor processing apparatus for a vehicle described in claim 3, the control means determines whether or not the running state is capable of performing the purge. Do not operate means. Accordingly, since the heating means is not operated when the running state is not purgeable, useless power consumption can be suppressed, and deterioration of the fuel consumption of the vehicle due to power consumption can be suppressed.

1 is a configuration diagram illustrating an evaporative fuel processing apparatus for a vehicle according to a first embodiment. It is a flowchart which shows the process sequence of ECU. 6 is a flowchart showing a processing procedure of an ECU according to the second embodiment. 6 is a flowchart illustrating a processing procedure of an ECU according to a third embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

[Embodiment 1]
Embodiment 1 will be described. In the present embodiment, an evaporative fuel processing apparatus applied to a vehicle including an internal combustion engine (engine) as a driving source for traveling is illustrated. FIG. 1 is a block diagram showing an evaporative fuel processing apparatus for a vehicle.
As shown in FIG. 1, an intake passage 12 and an exhaust passage 13 are connected to an engine 10 that is an internal combustion engine. An air cleaner 14 that filters air is provided on the upstream side of the intake passage 12. Air is introduced into the intake passage 12 via the air cleaner 14. An air flow meter 15 for detecting an intake air amount (intake air amount) introduced into the intake passage 12 is disposed on the downstream side of the air cleaner 14. A throttle valve 16 for adjusting the intake amount to the engine 10 is provided on the downstream side of the air flow meter 15. The throttle opening of the throttle valve 16 is adjusted by an electric motor as an actuator that is driven according to an operation amount of an accelerator pedal (not shown). Further, the air that has passed through the throttle valve 16 in the intake passage 12 flows through the surge tank 18 to the intake port 19 of each cylinder of the engine 10.

  Liquid fuel (gasoline) is stored in the fuel tank 20. The fuel in the fuel tank 20 is injected from an injector (fuel injection valve) 21 toward an intake port 19 of each cylinder of the engine 10 through a fuel supply path (not shown). The fuel becomes an air-fuel mixture mixed with the air flowing through the intake port 19 and is supplied to the combustion chamber 24 of each cylinder at the timing when the intake valve 23 is opened.

  The inside of the fuel tank 20 is connected to the inside of the case 31 of the canister 30 through the evaporated fuel passage 26. The case 31 is filled with activated carbon 32 as an adsorbent. Further, the inside of the case 31 is connected to the inside of the surge tank 18 via the purge passage 34. In the purge passage 34, a purge valve 36 controlled by an ECU 60 (described later) is provided. Further, the evaporated fuel passage 26 and the purge passage 34 are connected on one side (upper side) of the case 31, and an atmospheric port 38 that opens the inside of the case 31 to the atmosphere is formed on the other side (lower side) of the case 31. ing. The purge valve 36 executes and stops the purge to be sucked into the engine 10 and corresponds to “purge means” in the present specification.

  The evaporated fuel generated in the fuel tank 20 is adsorbed by the activated carbon 32 of the canister 30 through the evaporated fuel passage 26. When the purge valve 36 is opened according to the operating state of the engine 10, air is sucked into the purge passage 34 from the atmospheric port 38 through the canister 30 by the negative intake pressure. When the air passes through the canister 30, the evaporated fuel adsorbed on the activated carbon 32 is desorbed from the activated carbon 32, and the air containing the evaporated fuel, that is, the evaporated fuel gas, enters the surge tank 18 through the purge passage 34. Purged. This state is the purge on state, that is, the execution state. The state in which the purge valve 36 is closed is the purge off state, that is, the stop state.

  An electric heater (referred to as “heater”) 40 for heating the canister 30 (specifically, activated carbon 32) is disposed in the case 31 of the canister 30. Energization of the heater 40 is turned on / off by a heater switch 41. When the heater switch 41 is turned on, the canister 30 (specifically, activated carbon 32) is heated by energizing the heater 40. When the heater switch 41 is turned off, the power supply to the heater 40 is cut off. The heater 40 corresponds to “heating means” in this specification.

  The air-fuel mixture supplied into the combustion chamber 24 of each cylinder of the engine 10 is ignited and burned at a predetermined combustion timing by a spark plug (not shown). Then, the exhaust gas after combustion is discharged from the combustion chamber 24 to the exhaust passage 13 through the exhaust port 43 of each cylinder of the engine 10 at a timing when the exhaust valve 42 is opened. The engine 10 is provided with a water temperature sensor 45 for detecting the coolant temperature. The intake passage 12 is provided with an intake air temperature sensor 47 for detecting intake air temperature and an intake negative pressure sensor 49 for detecting intake negative pressure. The exhaust passage 13 is provided with an air-fuel ratio (A / F) sensor 51 for detecting the oxygen concentration in the exhaust gas.

  The ECU 60 is an electronic control unit, which is a CPU as a central processing unit that executes various known arithmetic processes, a ROM that stores control programs, a RAM that stores various data, a B / U (backup) RAM, an input / output The circuit is configured as a logic operation circuit including a circuit and a bus line connecting them. The ECU 60 also receives detection signals from the air flow meter 15, the water temperature sensor 45, the intake air temperature sensor 47, the intake air negative pressure sensor 49, the air-fuel ratio sensor 51, the vehicle speed sensor 53, the accelerator opening sensor 55, and other various sensors. Is entered. The vehicle speed sensor 53 detects the vehicle speed based on the number of rotations of the wheels (driven wheels). The accelerator opening sensor 55 detects the accelerator opening (the amount of operation of the accelerator pedal). The ECU 60 corresponds to “control means” in the present specification.

  Based on the control signal calculated by the ECU 60, the injector 21, the purge valve 36, the heater switch 41, the electric motor (not shown) of the throttle valve 16, and the like are controlled. Further, the ECU 60 determines whether or not the vehicle is running, that is, whether the vehicle is in a deceleration state, based on detection signals from the vehicle speed sensor 53 and the accelerator opening sensor 55. For example, it is determined that the vehicle is in a decelerating state when the vehicle speed is equal to or higher than a predetermined value and the accelerator opening is 0 (fully closed), and otherwise, it is determined that the vehicle is not in a decelerating state. The vehicle speed sensor 53 and the accelerator opening sensor 55 correspond to “running state detection means”. The vehicle speed sensor 53 corresponds to a “vehicle speed detection device” in this specification. The accelerator opening sensor 55 corresponds to an “accelerator opening detecting device” in this specification.

  Further, the accelerator opening sensor 55 as the traveling state detecting means can be replaced with the intake negative pressure sensor 49. That is, the ECU 60 determines that the vehicle is in a decelerating state when the vehicle speed is equal to or higher than a predetermined value and the intake negative pressure is equal to or higher than a predetermined value, and otherwise determines that the vehicle is not in a decelerating state. The intake negative pressure sensor 49 corresponds to an “intake negative pressure detection device” in this specification.

  The vehicle is provided with a battery 64 and an alternator 66 for supplying electric power to the electrical load 62. The electrical load 62 is a load of electrical components such as a vehicle headlamp, a rear combination lamp, a power window, a wiper, and an electric fan. The heater 40 is one of the electrical loads 62. The alternator 66 is connected to the crankshaft of the engine 10 via a pulley, a transmission belt, and the like, and generates electric power when the engine 10 is operated. The electric power generated by the alternator 66 is supplied to the electrical load 62 and the battery 64.

  The alternator 66 includes a stator coil wound around the stator as a three-phase coil, and a field coil wound around a rotor located inside the stator coil. The alternator 66 rotates the field coil in an energized state to generate an induced power in the stator coil, converts the induced current (three-phase alternating current) into a direct current by a rectifier, and charges the battery 64. The alternator 66 includes an IC regulator configured by a switching circuit. The IC regulator receives the battery voltage signal and adjusts the energization time of the field coil so that the battery voltage converges to an appropriate range. Specifically, when the battery voltage starts to decrease and the discharge amount tends to become excessive, the ratio of the energizing time to the field coil (field duty) is increased, and the field current flowing through the field coil is increased. . Also, when the battery voltage starts to rise and the amount of charge tends to be excessive, the field duty of the alternator 66 is decreased by reducing the field duty, and the field current flowing through the field coil is reduced. Reduce. By such an operation of the IC regulator, the state of charge of the battery 64 is maintained in an appropriate range. The field duty of the alternator 66 is input to the ECU 60. The alternator 66 collects the kinetic energy of the vehicle as electric energy and corresponds to the “regenerative means” in this specification.

Next, the processing procedure of the ECU 60 will be described. FIG. 2 is a flowchart showing the processing procedure of the ECU. This control routine is repeatedly executed by the ECU 60 every predetermined time.
As shown in FIG. 2, it is determined in step S102 whether or not the vehicle is decelerating. When the vehicle is decelerating, the purge is turned off in step S104. That is, the purge valve 36 (see FIG. 1) is closed. At this time, the purge valve 36 is closed when the valve is opened, and the closed state is continued when the valve is closed. Subsequently, in step S106, the heater 40 is turned on. That is, after the heater switch 41 (see FIG. 1) is turned on, this routine is finished. At this time, the heater switch 41 is turned on when it is off, and the on state is continued when it is on. Thereby, the canister 30 (specifically activated carbon 32) (see FIG. 1) is heated by energizing (actuating) the heater 40 (see FIG. 1). Therefore, since the temperature of the canister 30 can be raised before the next purge, it is possible to increase the amount of desorbed evaporated fuel at the next purge. If it is determined in step S102 that the vehicle is not decelerating, the heater is turned off in step S108, that is, the heater switch 41 is turned off, and then this routine is terminated. At this time, the heater switch 41 is turned off when the heater switch 41 is on, and the off state is continued when the heater switch 41 is off.

  According to the fuel vapor processing apparatus, purge is turned off, that is, stopped while the vehicle is running at a reduced speed, and the heater 40 is turned on, that is, operated using the electrical energy recovered by the alternator 66. For this reason, it is possible to prevent the heat of the heater 40 from being taken away by the purge air. As a result, useless consumption of electrical energy can be suppressed. At the same time, by operating the heater 40 using the electric energy generated by the alternator 66, the canister 30 can be heated without the heat of the heater 40 being taken away by the purge air. Therefore, it is possible to improve the heating efficiency of the canister 30 while effectively using the electrical energy recovered by the alternator 66.

[Embodiment 2]
A second embodiment will be described. Since the present embodiment is a modification of the first embodiment, the changed portion will be described and redundant description will be omitted.
The ECU 60 (see FIG. 1) functions as a power generation amount control means for controlling the power generation amount by controlling the field current of the alternator 66. The ECU 60 increases the amount of power generated by the alternator 66 by increasing the field current flowing in the field coil when the heater 40 (see FIG. 1) is operated in the deceleration traveling state, that is, when the heater switch 41 (see FIG. 1) is turned on. Let For example, the increase in the amount of power generated by the alternator 66 is equivalent to the power used by the heater 40.

Next, the processing procedure of the ECU 60 will be described. FIG. 3 is a flowchart showing a processing procedure of the ECU. In addition, since this control routine adds the change to the control routine (refer FIG. 2) in the said Embodiment 1, the changed part is demonstrated and the overlapping description is abbreviate | omitted.
As shown in FIG. 3, step S105 is added between step S104 and step S106. That is, in step S105, the power generation amount of the alternator 66 (see FIG. 1) is increased, and then the process proceeds to step S106.

  According to the present embodiment, the heating efficiency of the canister 30 can be improved by increasing the power generation amount of the alternator 66 when the heater 40 is operated in the deceleration traveling state. Further, as the amount of power generated by the alternator 66 increases, the load torque of the alternator 66 with respect to the engine 10 increases, which can contribute to braking of the vehicle.

[Embodiment 3]
A third embodiment will be described. Since the present embodiment is a modification of the second embodiment, the changed portion will be described and redundant description will be omitted.
The ECU 60 (see FIG. 1) has a function as a traveling state determination unit that determines whether or not it is a traveling state in which purging can be performed. When the coolant temperature detected by the water temperature sensor 45 (see FIG. 1) is equal to or higher than a predetermined value, or the intake air temperature detected by the intake air temperature sensor 47 (see FIG. 1) is within a predetermined range. On the other hand, it is determined that the running state is such that purging can be performed. That is, the ECU 60 prohibits purging in a traveling state in which drivability and exhaust emission may be significantly deteriorated when purging is performed when the engine 10 is warmed up, extremely hot, extremely hot, or the like. Therefore, in such a case, even when the vehicle is decelerating, turning on the heater 40 (see FIG. 1) consumes power wastefully. For this reason, when it is determined that the ECU 60 is not in a traveling state in which purging can be performed, the ECU 60 turns off the heater switch 41 and stops energization (operation) of the heater 40. The water temperature sensor 45 and the intake air temperature sensor 47 correspond to “running state detection means” in this specification.

Next, the processing procedure of the ECU 60 will be described. FIG. 4 is a flowchart showing the processing procedure of the ECU. Since this control routine is a modification of the control routine (see FIG. 3) in the second embodiment, the changed portion will be described and redundant description will be omitted.
As shown in FIG. 4, step S101 is added before step S102 of this control routine. That is, after the start of this control routine, in step S101, it is determined whether or not the running state is such that purging can be performed. If it is in a traveling state in which purging can be performed, the process proceeds to step S102. On the other hand, when the running state is not capable of purging, the routine is terminated after the heater is turned off, that is, the heater switch 41 is turned off in step S108. At this time, the heater switch 41 is turned off when the heater switch 41 is on, and the off state is continued when the heater switch 41 is off.

  According to the present embodiment, since the heater 40 is not operated when it is not in a running state in which purging can be performed, wasteful power consumption can be suppressed, and deterioration of vehicle fuel consumption due to power consumption can be suppressed. it can. Note that step S101 may be added before step S102 of the control routine (see FIG. 2) in the first embodiment.

  The present invention is not limited to the above-described embodiment, and modifications can be made without departing from the gist of the present invention. For example, the present invention can be applied not only to a vehicle including the engine 10 as a driving source for traveling but also to a hybrid vehicle including the engine 10 and an electric motor as a driving source for traveling. In this case, an electric motor can be used as the regeneration means.

10. Engine (internal combustion engine)
12 ... Intake passage 20 ... Fuel tank 30 ... Canister 34 ... Purge passage 36 ... Purge valve (purge means)
40 ... Heater (heating means)
53 ... Vehicle speed sensor (traveling state detecting means)
55. Accelerator opening sensor (running state detection means)
60 ... ECU (control means, power generation amount control means, travel state determination means)
66: Alternator (regenerative means)

Claims (3)

A canister for adsorbing evaporated fuel generated in a fuel tank mounted on the vehicle;
A purge means provided in a purge passage that communicates the canister and the intake passage of the engine, and performs a purge to perform and stop the purge of the evaporated fuel adsorbed by the canister to the engine;
Heating means for heating the canister;
Control means for controlling the purge means and the heating means;
Traveling state detecting means for detecting the traveling state of the vehicle;
Regenerative means for recovering the kinetic energy of the vehicle as electrical energy,
When the traveling state detected by the traveling state detecting unit is a decelerating traveling state, the control unit controls the purge unit to stop the purge, and uses the electric energy recovered by the regenerating unit. An evaporative fuel processing apparatus for a vehicle, wherein the heating means is operated. The evaporative fuel processing device for a vehicle according to claim 1,
A power generation amount control means for controlling the power generation amount generated by the regeneration means;
The evaporative fuel processing apparatus for a vehicle, wherein the power generation amount control means increases the power generation amount of the regeneration means when the heating means is operated in a decelerating running state. An evaporative fuel processing apparatus for a vehicle according to claim 1 or 2,
The control means determines whether or not the vehicle is in a traveling state in which purging can be performed, and when it is determined that the traveling state is not in a state in which purging can be performed, the heating unit is not operated, apparatus.

Images