JP2007077918A - Fuel changeover control device of dual fuel engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an occupant of a vehicle from feeling a sense of incongruity due to torque shock caused by changeover of used fuel to the greatest possible extent when the used fuel of an engine is automatically changed over, in a vehicle composed by mounting a dual fuel engine capable of changing over the used fuel from a gas fuel to gasoline and vice versa. <P>SOLUTION: When the changeover of the used fuel is determined, the changeover of the used fuel is annunciated to the occupant of the vehicle (step S11); and the changeover of the used fuel is executed after the annunciation (step S15). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention belongs to a technical field related to a fuel switching control device of a dual fuel engine that can switch between gaseous fuel and gasoline as a fuel to be used.

In recent years, from the viewpoint of environmental problems and the like, a dual fuel engine has been actively developed as an engine for vehicles such as automobiles. This dual fuel engine, for example, as shown in Patent Document 1 and Patent Document 2, enables switching between gas fuel such as natural gas and gasoline as the fuel used. It is also known to use hydrogen as a gaseous fuel (see, for example, Patent Document 3).
JP 7-34915 A JP 2001-193511 A JP 2005-155528 A

  In the dual fuel engine as described above, a predetermined condition for switching the used fuel is set in advance, and the used fuel is automatically switched when the predetermined condition is satisfied. Conceivable.

  However, when the fuel to be used is automatically switched, the occupant of the vehicle equipped with the dual fuel engine is uncomfortable at the time of switching. That is, as also shown in Patent Documents 1 and 2 described above, when the fuel used is switched, a torque shock occurs due to a difference in fuel properties, a response delay in the control system, and the like. Unlike, for example, a torque shock that occurs during a speed change operation, it occurs unexpectedly for the vehicle occupant, and the occupant feels a great sense of discomfort.

  The present invention has been made in view of such a point, and an object of the present invention is to provide a vehicle equipped with a dual fuel engine as described above when the fuel used in the engine is automatically switched. It is intended to prevent the passengers from feeling as uncomfortable as possible from the torque shock caused by the switching of the fuel used.

  In order to achieve the above object, according to the present invention, when the decision to switch the fuel to be used is made, the vehicle occupant is notified that the fuel to be used has been switched. Changeover was executed.

  Specifically, the invention of claim 1 is directed to a fuel switching control device for a dual fuel engine that is mounted on a vehicle and that can switch between gaseous fuel and gasoline as the fuel used.

  And when a predetermined condition is satisfied, a decision means for deciding to switch the fuel to be used, and when a decision to switch the fuel to be used is made by the decision means, In addition, it is assumed that there is provided notification means for informing that there is a change in the used fuel, and switching execution means for executing the change in the used fuel after notification by the notification means.

  With the above configuration, when the determination unit determines to switch the fuel to be used, the notification unit notifies the vehicle occupant that the fuel to be used has been switched. Fuel switching is performed. Therefore, since the vehicle occupant is informed in advance that the fuel to be used is switched before the fuel is switched, even if a torque shock occurs due to the fuel switching, the passenger will It can be determined that this is caused by the switching of the fuel used, and it is difficult to feel a sense of incongruity due to the torque shock accompanying the switching of the fuel used.

  According to a second aspect of the present invention, in the first aspect of the invention, the vehicle further comprises a deceleration operation detecting means for detecting that the vehicle occupant has performed a deceleration operation for decelerating the vehicle. After the notification by the notification means, it is assumed that when the deceleration operation detecting means detects the occupant's deceleration operation, the fuel used is switched.

  This makes it possible to synchronize the torque shock that accompanies the switching of the fuel used and the shock due to the deceleration of the vehicle, thereby making it more difficult for the occupant to feel a sense of discomfort due to the torque shock accompanying the switching of the fuel used.

  According to a third aspect of the present invention, in the second aspect of the present invention, the notification by the notification means is a notification that there is a change in the fuel used for the occupant, and prompts the occupant to perform the deceleration operation. The notifying means does not detect the deceleration operation of the occupant by the deceleration operation detecting means after a predetermined time has elapsed since the start of the first notification performed when the decision of switching of the used fuel is made by the determining means. In some cases, the occupant is configured to perform re-notification in a form that is easier to recognize than at the time of the first notification.

  That is, in the invention of claim 2, even if it is determined to switch the used fuel, the switching of the used fuel is not executed unless the deceleration operation is performed by the occupant. However, according to the present invention, when the notification means prompts the occupant to perform a deceleration operation and the deceleration operation is not performed even after a predetermined time has elapsed since the first notification, the occupant is more aware than at the time of the first notification. Since the re-notification is performed in an easy-to-use form, there is no longer a situation where the deceleration operation is not performed for a long time after the decision to switch the fuel used, and the fuel switching can be executed at the earliest possible stage. become.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the notification by the notification means is performed by voice, and the notification means is configured such that when the re-notification is performed, the volume of the voice is higher than that during the first notification. It shall be comprised so that may be enlarged.

  Thus, by increasing the volume at the time of re-notification, the re-notification is easily recognized by the occupant and the deceleration operation is more reliably performed by the occupant.

  According to a fifth aspect of the present invention, in the third aspect of the invention, the notification by the notification means is performed by a switching notification lamp, and the notification means continuously turns on the switching notification lamp at the time of the first notification. On the other hand, it is assumed that the switching notification lamp blinks at the time of the re-notification.

  Accordingly, by blinking the switching notification lamp at the time of re-notification, the re-notification is easily recognized by the occupant, and the occupant can perform the deceleration operation more reliably.

  As described above, according to the fuel switching control device of the dual fuel engine of the present invention, when the determination of the switching of the used fuel is made, the vehicle occupant is notified that there is a switching of the used fuel, By switching the used fuel after this notification, it is possible to prevent the passenger from feeling uncomfortable due to a torque shock accompanying the switching of the used fuel.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 schematically shows the configuration of a fuel switching control device for a dual fuel engine according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a rotary engine. The rotary engine 1 is mounted on a vehicle such as an automobile, and can switch between gaseous fuel (hydrogen in this embodiment) and gasoline as the fuel used. It is considered as a dual fuel engine.

  The rotary engine 1 includes a rotor housing chamber (hereinafter referred to as a cylinder) 11 surrounded by a bowl-shaped rotor housing having a trochoid inner peripheral surface and a side housing, and a substantially triangular rotor 12 accommodated therein. In addition, three working chambers are defined on the outer peripheral side of the rotor 12. Although not shown, the rotary engine 1 is formed by integrating two rotor housings so as to be sandwiched between three side housings, and the rotors 12 and 12 are accommodated in two cylinders 11 and 11 formed therebetween, respectively. In FIG. 1, the two cylinders 11 and 11 are shown in an expanded state.

  Each of the rotors 12 rotates around the eccentric shaft 13 with the seal portions respectively disposed at the three tops of the outer periphery of the rotor 12 in contact with the inner peripheral surface of the trochoid of the rotor housing. Revolves around 13 axes. Then, while the rotor 12 makes one revolution, the working chambers formed between the tops of the rotor 12 move in the circumferential direction to perform intake, compression, expansion (combustion), and exhaust strokes. Is generated from the eccentric shaft 13 via the rotor 12.

  Each cylinder 11 of the rotary engine 1 is provided with two spark plugs 14, 14. The two spark plugs 14, 14 are respectively disposed near the minor axis of the rotor housing, Each cylinder 11 is provided with two hydrogen injection injectors 4 for directly injecting hydrogen as gaseous fuel supplied from a hydrogen tank (not shown) into the cylinder (in FIG. The two injectors 4 provided in each cylinder 11 are arranged side by side in the axial direction of the eccentric shaft 13 in the vicinity of the long axis of the rotor housing.

  In addition, the intake passage 2 communicates with each cylinder 11 so as to communicate with the working chamber in the intake stroke, and the exhaust passage 3 communicates with the working chamber in the exhaust stroke. The intake passage 2 is one on the upstream side, but is divided into two on the downstream side and communicates with the working chambers of the cylinders 11. Further, two exhaust passages 3 are provided on the upstream side so as to communicate with the working chambers of the respective cylinders 11, but are joined together on the downstream side.

  A throttle valve 22 that is driven by an actuator 21 such as a stepping motor and adjusts the cross-sectional area (valve opening) of the passage 2 is disposed upstream of the branch portion of the intake passage 2. Downstream of the section, gasoline injectors 5 and 5 for injecting gasoline supplied from a gasoline tank (not shown) into the intake passage 2 (branched portion) are arranged.

  The ignition plugs 14, the actuators 21 of the throttle valves 22, and the injectors 4 and 5 for hydrogen and gasoline injection are controlled by a power train control module (hereinafter referred to as PCM) 6. That is, each spark plug 14 is ignited at a predetermined timing according to the rotational position of the rotor 12. Further, the actuator 21 of the throttle valve 22 is controlled by the PCM 6 in accordance with an output signal of an accelerator opening sensor 52 described later to adjust the opening of the throttle valve 22. In other words, the opening value of the throttle valve 22 corresponds to the output value of the throttle opening sensor 52 (the actuator 21 also serves as the actuator 21 in this embodiment) that detects the opening. To adjust to a predetermined value. Further, the injector 4 for hydrogen injection injects hydrogen into the cylinder 11 (working chamber) at a predetermined timing according to the rotational position of the rotor 12 when the fuel used is hydrogen, and the injector 5 for gasoline injection. Injects gasoline into the intake passage 2 at a predetermined timing according to the rotational position of the rotor 12 when the fuel used is gasoline.

  The PCM 6 includes at least the brake pedal of the vehicle occupant in addition to signals necessary for controlling the operation of the ignition plugs 14, the actuators 21 of the throttle valves 22, and the injectors 4 and 5 for hydrogen and gasoline injection. A brake sensor 51 for detecting the amount, an accelerator position sensor 52 for detecting the amount of depression of the passenger's accelerator pedal (accelerator position), and a GPS signal transmitted from a GPS satellite to detect the current position of the vehicle Each output signal of the GPS sensor 53 to be input is input.

  The PCM 6 includes the brake sensor 51, the accelerator opening sensor 52, and the GPS sensor 53 in addition to the operation control of the ignition plugs 14, the actuator 21 of the throttle valve 22, and the injectors 4 and 5 for hydrogen and gasoline injection. Based on each output signal, the voice output unit 61 and the switching notification lamp 62 of the navigation device are controlled. The voice output unit 61 of the navigation device generates an output signal to a speaker of the navigation device to perform route voice guidance and the like. The switching notification lamp 62 is provided on the instrument panel of the vehicle together with an instrument such as a speedometer so that a vehicle occupant can visually recognize it.

The fuel used in the rotary engine 1 is hydrogen when the current position of the vehicle is within a predetermined CO ₂ and NO _x emission control area (for example, within a specific city area), and when the vehicle is outside the emission control area. Use gasoline. In other words, when the vehicle goes out of the emission control area from outside the emission control area, the fuel used is automatically switched from hydrogen to gasoline. To automatically switch to. The PCM 6 determines whether or not the vehicle exists within the emission control area based on the output signal of the GPS sensor 53.

  In this embodiment, when the vehicle goes out of the emission control area from outside the emission control area or enters the emission control area from outside the emission control area (that is, when a predetermined condition is satisfied), the fuel used immediately First, the PCM 6 decides to switch the used fuel. Thus, the PCM 6 constitutes a determination unit that determines to switch the fuel to be used when a predetermined condition is satisfied.

  When the decision to switch the fuel used is made, the PCM 6 controls the voice output unit 61 and the switching notification lamp 62 of the navigation device to notify the vehicle occupant that the fuel used is switched. . As a result, the PCM 6, the voice output unit 61 of the navigation device, and the switching notification lamp 62 indicate that there is a switching of the fuel to be used by the vehicle occupant when the switching of the fuel is determined by the determining means. An informing means for informing is configured. By this notification means, for example, the above-mentioned notification is performed and a switching notification lamp 62 is generated by emitting a sound such as “switch fuel to be used from now on, decelerate the vehicle” once from the speaker of the navigation device. Is continuously lit, and the above notification is made, for example, by shining the letters “I will switch the fuel to be used. Please decelerate the vehicle”. If the occupant understands the meaning of lighting of the switching notification lamp 62 in advance, there is no need for such characters.

  The PCM 6 also constitutes a switching execution means, and switches the used fuel after the notification. However, in this embodiment, after the notification, it is detected by the brake sensor 51 or the accelerator opening sensor 52 as the deceleration operation detection means that the vehicle occupant has performed a deceleration operation for decelerating the vehicle. Switch the fuel used. That is, when it is detected that the occupant has performed an operation of depressing the brake pedal or an operation of returning the accelerator pedal from the depressed state, the switching of the fuel to be used is executed. With this configuration, since the occupant's decelerating operation must be detected in order to switch the fuel used, the above notification is a notification that there is a change in the fuel used for the occupant, and to the occupant As shown in the above example, in addition to the voice saying “I will change the fuel to be used” as shown above, a voice like “Please decelerate the vehicle” is emitted from the speaker of the navigation device. I am doing so.

  Further, in the present embodiment, after a predetermined time (for example, 1 to 2 minutes) has elapsed since the start of the first notification performed when the decision to switch the fuel used is made, when the occupant's deceleration operation is not detected, Re-notification is performed to the passenger in a form that is easier to recognize than at the time of the first notification. That is, at the time of re-notification, the volume of the sound is increased from that at the time of the first notification, thereby making it easier for the occupant to recognize that there is a change in the fuel used than at the time of the first notification and strongly urging the deceleration operation. In addition, at the time of the first notification, only the switching notification lamp 62 is lit continuously, but at the time of re-notification, the switching notification lamp 62 blinks, so that there is a change in the fuel used than at the time of the first notification. Makes it easier for the occupant to recognize, and strongly encourages deceleration operation. In the present embodiment, even when the predetermined time has elapsed since the start of the re-notification, when the occupant's deceleration operation is not detected, the volume of the sound is made larger than the re-notification and the switching notification lamp 62 blinks. Increase the speed and notify again. Thus, the notification is repeated every predetermined time until the occupant's deceleration operation is detected, so that the occupant can more easily recognize that there is a change in the fuel used than at the time of the previous notification, and the deceleration operation is strongly urged.

  When the occupant's deceleration operation is detected and fuel switching is performed, if gasoline is injected into the intake passage 2 by the injector 5 for gasoline injection, after the gasoline injection is stopped, When hydrogen is injected into the cylinder 11 by the injector 4 for hydrogen injection and hydrogen is injected by the injector 4 for hydrogen injection, the hydrogen injection is stopped and then the gasoline 5 is injected by the injector 5 for gasoline injection. Will be injected. Further, the switching notification lamp 62 is turned off as the fuel used is switched.

  Next, a specific processing operation regarding the switching of the fuel used in the PCM 6 will be described with reference to FIGS.

First, in the first step S1, the output signal (GPS information) of the GPS sensor 53 and the information on the currently used fuel are input. In the next step S2, the current position of the vehicle is determined based on the GPS information. determines whether the emissions regulations in the area of ₂ and NO _x. When the determination in step S2 is YES, the process proceeds to step S3. When the determination in step S2 is NO, the process proceeds to step S6.

  In step S3, which proceeds when the determination in step S2 is YES, it is determined whether or not the currently used fuel is hydrogen. When the determination in step S3 is YES, the process proceeds to step S4 and hydrogen is supplied. On the other hand, if the determination is NO in step S3, the process proceeds to step S5, where the fuel switching from gasoline to hydrogen is determined, and then the process proceeds to step S11.

  On the other hand, in step S6 that proceeds when the determination in step S2 is NO, it is determined whether or not the currently used fuel is gasoline. When the determination in step S6 is YES, the process proceeds to step S7. On the other hand, if the determination is NO in step S6, the process proceeds to step S8, where fuel switching from hydrogen to gasoline is determined, and then the process proceeds to step S11.

  In step S11 following step S5 or S8, the voice output unit 61 of the navigation device is controlled to notify that there is a change in the fuel to be used by voice from the speaker of the navigation device (to prompt the occupant to perform a deceleration operation). In addition, the switching notification lamp 62 is turned on.

  In the next step S12, a timer is set and started. In the next step S13, output signals (output values) of the brake sensor 51 and the accelerator opening sensor 52 are read. In the next step S14, based on the output values. Then, it is determined whether an occupant deceleration operation has been detected.

  When the determination in step S14 is YES, the process proceeds to step S15 to switch the fuel used, and the switching notification lamp 62 is turned off, and then the process returns.

  On the other hand, when the determination in step S14 is NO, the process proceeds to step S16, where the timer determines whether a predetermined time has elapsed since the start of the previous notification, and when the determination in step S16 is NO. On the other hand, the process returns to step S13, while if the determination in step S16 is YES, the process proceeds to step S17.

  In step S17, the sound volume is increased from the previous notification to notify that there is a change in fuel used (including prompting the occupant to decelerate), and the change notification lamp 62 blinks. (In the third and subsequent notifications, the blinking speed is made faster than in the previous notification), after which the process returns to step S12 to reset the timer, and the processing operations in and after step S13 are repeated.

  As a result of the processing operation of the PCM 6, when the vehicle enters the emission regulation area from outside the emission regulation area where gasoline is used as fuel, it is determined that the fuel to be used is switched from gasoline to hydrogen. In addition, when the vehicle goes out of the emission control area where hydrogen has been used as the fuel, it is determined to switch the fuel used from hydrogen to gasoline.

  When the above determination is made, a sound such as “Switch the fuel to be used from now on, decelerate the vehicle” is emitted once from the speaker of the navigation device, and the switching notification lamp 62 is continuously lit. This notifies the occupant that the fuel to be used is switched and prompts the occupant to perform a deceleration operation. This notification allows the occupant to know in advance that there is a change before the change of the fuel used.

  When the passenger depresses the brake pedal or decelerates the vehicle by performing an operation of returning the accelerator pedal from the depressed state, the fuel to be used is switched in synchronization with the deceleration of the vehicle. As a result, a torque shock associated with the switching of the fuel used and a shock due to the deceleration of the vehicle occur simultaneously. As a result, the occupant knows that there is a switching of the fuel used in advance. The feeling of incongruity due to the torque shock associated with the changeover is hardly felt.

  On the other hand, if a passenger's deceleration operation is not detected after a predetermined time has elapsed since the start of the first notification performed when the decision to switch the fuel used is made, it is re-notified in a form that is easier to recognize than at the time of the first notification. Is done. That is, at the time of re-notification, the volume of the sound emitted from the speaker of the navigation device becomes larger than that at the time of the first notification, and the switching notification lamp 62 blinks. This makes it easier for the occupant to notice that there is a change in the fuel used, and there is no possibility that the deceleration operation will not be performed for a long time after the decision to switch the fuel used.

  Further, even after the predetermined time has elapsed since the start of re-notification, when the occupant's deceleration operation is not detected, re-notification is performed, and at the time of this re-notification, the volume of the sound becomes larger than the re-notification. The blinking speed of the switching notification lamp 62 is increased.

  Therefore, in the present embodiment, when it is determined that the fuel to be used is switched, the vehicle occupant is notified that the fuel to be used is switched, and after this notification, the fuel to be used is switched. Therefore, even if a torque shock occurs due to the switching of the fuel used, the occupant can determine that the torque shock is caused by the switching of the fuel used, and feel uncomfortable due to the torque shock accompanying the switching of the fuel used. It becomes difficult to feel.

  In addition, since the switching of the fuel used is performed when the occupant's deceleration operation is detected, the torque shock accompanying the switching of the fuel used and the shock due to the deceleration of the vehicle occur at the same time. Coupled with knowing that there is a change in the fuel used, there is almost no sense of incongruity due to the torque shock accompanying the change in the fuel used.

  On the other hand, when the occupant's deceleration operation is detected in this way, the change of the fuel to be used is executed. Switching will not be performed. However, in the above embodiment, the notification to the occupant is a notification that there is a change in the fuel used for the occupant, and prompts the occupant to perform a deceleration operation for decelerating the vehicle. When a predetermined time has elapsed since the start of the first notification performed when the fuel switching decision is made, when the occupant's deceleration operation is not detected, the passenger is more easily recognized than the first notification. Since the re-notification is performed at this point, it is no longer possible to decelerate the fuel for a long time after the decision to switch the fuel used, and the fuel switching can be executed at the earliest possible stage.

  In the above embodiment, as a predetermined condition for deciding to switch the fuel to be used, when the vehicle goes out of the emission control area or out of the emission control area, the vehicle enters the emission control area. However, the predetermined condition may be anything. For example, when either one of the fuels is exhausted, or when the temperature of the catalyst is lower than the threshold value from a state higher than a threshold value (temperature at which the catalyst is activated) or from a state lower than the threshold value For example, when the vehicle becomes higher than the threshold value, the driving state of the vehicle becomes a predetermined state.

  Further, in the above embodiment, the change of the used fuel is performed when the occupant's deceleration operation is detected, but the change of the used fuel is performed after the notification to the occupant. Regardless of the deceleration operation, it may be performed at any timing (for example, immediately after the notification or at a set time), and it is not necessary to prompt the occupant to perform the deceleration operation. In particular, when it is determined to switch the used fuel when either one of the fuels is exhausted, it is desirable to execute the switching of the used fuel immediately after notifying the passenger. In this way, even if switching is performed regardless of the occupant's deceleration operation, the occupant knows that there is a change in the fuel used by notifying that there is a change in the fuel used. It becomes difficult to feel.

  Furthermore, in the above-described embodiment, the present invention is applied to the rotary engine 1 that can switch between hydrogen and gasoline as the fuel to be used. However, a dual fuel engine (rotary engine) that can switch between gas fuel such as natural gas and gasoline. The present invention can also be applied to (but not limited to).

  INDUSTRIAL APPLICABILITY The present invention is useful for a fuel switching control device for a dual fuel engine that can switch between gaseous fuel and gasoline as the fuel used.

It is a schematic block diagram which shows the fuel switching control apparatus of the dual fuel engine which concerns on embodiment of this invention. It is a flowchart which shows the first half part of the processing operation regarding the switching of the fuel used in a powertrain control module. It is a flowchart which shows the latter half part of the processing operation regarding the switching of the fuel used in a powertrain control module.

Explanation of symbols

1 Rotary engine (dual fuel engine)
6 Powertrain control module (determination means) (notification means) (switching execution means)
51 Brake sensor (deceleration operation detection means)
52 Accelerator opening sensor (deceleration operation detection means)
61 Voice output unit (notification means) of navigation device
62 Switching notification lamp (notification means)

Claims (5)

A fuel switching control device for a dual fuel engine mounted on a vehicle and capable of switching between gaseous fuel and gasoline as fuel used,
Determining means for determining to switch the used fuel when a predetermined condition is satisfied;
An informing means for informing the occupant of the vehicle that there is a change in the used fuel when the determining means determines the change in the used fuel;
A fuel switching control device for a dual fuel engine, comprising: a switching execution means for switching the used fuel after notification by the notification means. The fuel switching control device for a dual fuel engine according to claim 1,
A deceleration operation detecting means for detecting that the vehicle occupant has performed a deceleration operation for decelerating the vehicle;
The switching execution means is configured to execute switching of the fuel to be used when a deceleration operation of the occupant is detected by the deceleration operation detection means after notification by the notification means. A fuel switching control device for a dual fuel engine. The fuel switching control device for a dual fuel engine according to claim 2,
The notification by the notification means is a notification that there is a change in fuel used for the occupant, and prompts the occupant to perform the deceleration operation.
The notifying means does not detect the deceleration operation of the occupant by the deceleration operation detecting means after a predetermined time has elapsed since the start of the first notification performed when the decision of switching of the used fuel is made by the determining means. In some cases, the fuel change control device for a dual fuel engine is configured to re-notify the occupant in a form that is easier to recognize than at the time of the first notification. The fuel switching control device for a dual fuel engine according to claim 3,
The notification by the notification means is performed by voice,
The fuel switching control device for a dual fuel engine, wherein the notifying means is configured to increase the volume of the sound at the time of the re-notification than at the time of the first notification. The fuel switching control device for a dual fuel engine according to claim 3,
The notification by the notification means is performed by a switching notification lamp,
The notification means is configured to continuously turn on the switching notification lamp at the time of the first notification, and to blink the switching notification lamp at the time of the re-notification. Control device.

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