JP2009209901A - Fuel supply device of engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel supply device of an engine capable of preventing fuel of a desired component from becoming insufficient, by securing a separation speed of the fuel, by generating sufficient differential pressure between the impermeable side and the permeable side of a separation film, by using various on-vehicle devices. <P>SOLUTION: This fuel supply device of the engine is mounted on a vehicle, and supplies respective fuels after separation to the engine via mutually different supply passages, by separating a specific component by permeating through the separation film 9a by the differential pressure between the impermeable side and the permeable side of the separation film 9a, by supplying raw fuel to the impermeable side of the separation film 9a, and includes a pressure accumulating device 3 for generating the differential pressure by releasing a pressure accumulating state in response to a vehicle state, while being put in the pressure accumulating state by torque of the engine. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an engine fuel supply device, and more particularly to a technique for generating a differential pressure between a non-permeation side and a permeation side of a separation membrane when raw fuel is separated by a separation membrane.

  In the fuel supply device described in Patent Document 1, the raw fuel is separated into a high RON fuel having a higher octane number than that of the raw fuel and a low RON fuel having a lower octane number than that of the raw fuel by using a separation membrane. In response, either one or both of high RON fuel and low RON fuel are supplied to the engine.

In this way, the combustion state is improved by changing the octane number of the fuel supplied to the engine according to the operating state, thereby increasing the output of the engine and improving the exhaust properties.
JP 2004-522039 A

  However, in the thing of patent document 1, since the differential pressure is generated between the non-permeation side and the permeation side of the separation membrane only by the driving force of the pump, when the driving force of the pump is small or the pump is driven When this is not possible, the differential pressure between the non-permeate side and the permeate side of the separation membrane is not sufficiently increased, and the fuel separation rate is reduced.

  When one of the high RON fuel and the low RON fuel is insufficient due to such a decrease in the fuel separation speed, the fuel supplied to the engine is biased only to the other fuel, resulting in a decrease in exhaust properties, a decrease in output or fuel consumption. Decrease.

  Therefore, we would like to use various in-vehicle devices other than the pump to generate a sufficient differential pressure between the non-permeate side and the permeate side of the separation membrane to ensure the fuel separation speed. There is no particular description in Document 1.

  The present invention has been made in view of the conventional problems as described above, and generates a sufficient differential pressure between the non-permeation side and the permeation side of the separation membrane using various in-vehicle devices. An object of the present invention is to provide an engine fuel supply device that can secure a fuel separation speed and prevent a shortage of fuel of a desired component.

  For this reason, the present invention is mounted on a vehicle, supplies raw fuel to the non-permeate side of the separation membrane, and allows a specific component to permeate the separation membrane by the differential pressure between the non-permeate side and the permeate side of the separation membrane. A fuel supply device for an engine that supplies the separated fuel to the engine via different supply paths, and is stored in an accumulated state by the rotational force of the engine. A pressure accumulating device that releases the state and generates the differential pressure is included.

  With the above configuration, the pressure accumulating device is brought into a pressure accumulating state by the rotational force of the engine, while releasing the pressure accumulating state according to the state of the vehicle to generate a differential pressure between the non-permeating side and the permeating side of the separation membrane. The fuel can be separated by the separation membrane.

  Here, if an in-vehicle device that is originally used other than fuel separation is used as a pressure accumulator, a differential pressure between the non-permeation side and the permeation side of the separation membrane is generated by the in-vehicle device that is originally used other than fuel separation, The fuel can be separated by the separation membrane.

The first embodiment of the present invention will be described below.
FIG. 1 is a diagram showing a system configuration of the present embodiment.
In FIG. 1, a vehicle engine 1 supplies each fuel separated in a fuel separator 2 to each cylinder through mutually different supply paths, and generates driving force by ignition and combustion of the fuel in each cylinder. And drive the vehicle.

A pressure accumulating device 3 is connected to the engine 1, and the pressure accumulating device 3 is brought into a pressure accumulating state by the rotational force of the engine 1 as will be described in detail later.
Further, the pressure accumulating device 3 is connected to the fuel separator 2 and can release the pressure accumulating state with respect to the fuel separator 2 as will be described in detail later.

A part of the output of the engine 1 can be used for power generation by the generator 5, and the generated power is charged to the battery 4.
The battery 4 supplies power to some devices (such as the heater 8) in the fuel separator 2 described later.

FIG. 2 shows details of the configuration of the fuel separator 2 and the pressure accumulator 3.
In the fuel separation device 2, the raw fuel is supplied to the separation membrane module 9 through the primary tank 6, the pressure feeding mechanism 7, and the heater 8 in this order.

  In the separation membrane module 9, the raw fuel is supplied to the non-permeating side of the separation membrane 9 a, and a specific component (for example, a specific component based on the octane number) in the raw fuel is obtained by a differential pressure between the non-permeating side and the permeating side of the separation membrane 9 a. ) Passes through the separation membrane 9a and is separated.

  The fuel that has passed through the separation membrane 9a is supplied to the gas-liquid separator 12, and as this supply passage, a passage 18 that interposes a vacuum pump (hereinafter simply referred to as a pump) 10 driven by the engine 1, A passage 19 for interposing the negative pressure mechanism 11 is provided in parallel.

The passage 19 is provided with a valve 27 on the upstream side of the negative pressure mechanism 11.
This valve 27 is opened at least when the pump 10 is stopped and when the fuel pressure Plae in the passage 19 downstream from the valve 27 is less than the fuel pressure Pvp in the passage 18 downstream from the pump 10. Controlled to valve.

The fuel from which bubbles are removed by the gas-liquid separator 12 is supplied to the secondary tank 13.
Further, the fuel that has not permeated through the separation membrane 9 a is supplied to the secondary tank 14.
Then, the fuel to be supplied to the engine 1 is selected from the fuel stored in the secondary tank 13 or the fuel stored in the secondary tank 14 according to the operating state of the engine 1.

  The differential pressure between the non-permeate side and the permeate side of the separation membrane 9a can be generated by either the operation of the pressure accumulator 3 or the driving of the pump 10. That is, the source of the differential pressure can be switched between the pressure accumulator 3 and the pump 10.

Hereinafter, a configuration in which the differential pressure between the non-permeation side and the permeation side of the separation membrane 9a is generated by the high pressure storage unit 15 for the air of the pressure accumulator 3 will be described.
The high pressure storage unit 15 for air is connected to the pressure feeding mechanism 7 through a pressure transmission passage 31 having a valve 21 interposed therebetween.

In addition, a cylinder 41 capable of stopping combustion at the time of reduced-cylinder operation is connected to the high-pressure storage unit 15 for air via a pressure transmission passage 34 provided with a valve 24.
The reduced-cylinder operation is performed when the required output of the engine 1 is small, such as during deceleration operation.

  Specifically, the pressure transmission passage 34 may be formed so as to communicate with the upper portion of the combustion chamber 50 of the cylinder 41 as shown in FIG. In FIG. 3, reference numeral 51 denotes an intake port, 52 denotes an exhaust port, 53 denotes an intake valve, 54 denotes an exhaust valve, and 55 denotes a piston.

  Here, the cylinder 41 that has stopped combustion during the reduced-cylinder operation compresses the air in the cylinder by the rotational force of the engine 1, but the pressure Pha of the high-pressure storage 15 for air is lower than the maximum pressure Phav when the cylinder 41 is compressed. By opening the valve 24, a part of the air compressed to the maximum in the cylinder 41 can be taken into the high pressure storage unit 15 for air via the pressure transmission passage 34. Thereby, the high pressure storage unit 15 for air is set in a pressure storage state.

  When the pressure Pha of the high pressure storage unit 15 for air is higher than the minimum pressure Phac necessary for pumping the raw fuel by driving the pumping mechanism 7, the valve 21 is opened to open the high pressure storage unit 15 for the air. The pressure accumulation state can be released to the pressure feeding mechanism 7 via the pressure transmission passage 31.

By releasing the pressure accumulation state, the pressure feeding mechanism 7 is driven by air pressure, so that the non-permeation side of the separation membrane 9a can be set to a higher pressure than the permeation side.
The valve 24 is controlled to be fully closed during the combustion operation of the cylinder 41 to prevent air-fuel mixture and exhaust gas from being taken into the high-pressure storage unit 15 for air, but from the high-pressure storage unit 15 side for air to the cylinder 41. You may comprise also the function of the non-return valve which prevents the movement of the air to the side.

Next, a configuration in which the differential pressure between the non-permeation side and the permeation side of the separation membrane 9a is generated by the high-pressure fuel storage unit 16 of the pressure accumulator 3 will be described.
The high-pressure fuel storage unit 16 is connected to the non-permeation side (upstream side) of the separation membrane 9 a in the separation membrane module 9 via the pressure transmission passage 32 having the valve 22 interposed therebetween.

In addition, a common rail 42 is connected to the high-pressure fuel storage unit 16 via a pressure transmission passage 35 having a valve 25 interposed therebetween.
Specifically, the high-pressure fuel storage unit 16 may be configured by attaching an accumulator 60 including a piston 61 and a spring 62, as shown in FIG.

  The common rail 42 includes a high pressure pump (not shown) driven by the engine 1 in order to keep the fuel at a high pressure. When the high pressure pump is driven, the fuel pressure of the common rail 42 fluctuates, and this is a high pressure storage for fuel. Although it may propagate to the part 16, the spring 62 absorbs the fluctuation of the fuel pressure acting on the piston 61, so that the fuel pressure of the high-pressure fuel storage part 16 can be maintained substantially constant.

  Here, when the fuel pressure Phf of the high-pressure fuel storage unit 16 is lower than the fuel pressure Phfv of the common rail 42, the high fuel pressure in the common rail 42 is increased via the pressure transmission passage 35 by opening the valve 25. It can be led to the high-pressure storage unit 16. As a result, the high-pressure fuel storage unit 16 is in a pressure accumulation state.

  The valve 25 may simply be a check valve that prevents the movement of fuel from the fuel high-pressure storage 16 side to the common rail 42 side, but in order to maintain the fuel pressure of the common rail 42 substantially constant, It is preferable to combine the function of opening the valve at a predetermined pressure or higher and sending the fuel to the high-pressure fuel storage unit 16 side and the function of the check valve.

  When the fuel pressure Phf of the fuel high-pressure storage unit 16 is higher than the pressure Phfs on the non-permeate side of the separation membrane 9a, the valve 22 is opened to change the pressure storage state of the fuel high-pressure storage unit 16 to the pressure transmission path. 32 can be released to the non-permeate side of the separation membrane 9a.

By releasing the pressure accumulation state, the non-permeate side of the separation membrane 9a can be set to a higher pressure than the permeate side.
Hereinafter, a configuration in which the negative pressure storage unit 17 of the pressure accumulator 3 generates a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a will be described.

The negative pressure storage unit 17 is connected to the negative pressure mechanism 11 via a pressure transmission passage 33 with a valve 23 interposed.
In addition, a master back 43 of a brake booster is connected to the negative pressure storage unit 17 through a pressure transmission passage 36 having a valve 26 (the details are also shown in FIG. 5).

  Here, when the pressure Pla of the negative pressure storage unit 17 is higher than the pressure Plav of the master back 43, the intake negative pressure of the master back 43 is transferred via the pressure transmission passage 36 by opening the valve 26. 17 can be led. Thereby, the negative pressure storage part 17 is made into a pressure accumulation state.

The valve 26 may simply be a check valve that prevents the movement of air from the master back 43 side to the negative pressure storage unit 17 side, but may be configured to control opening and closing.
When the pressure Pla of the negative pressure storage unit 17 is lower than the pressure Pfa of the negative pressure mechanism 11 (on the side of the pressure transmission passage 33 from the piston 11b in the cylinder 11a), the negative pressure storage unit 17 is opened by opening the valve 23. This pressure accumulation state can be released to the negative pressure mechanism 11 (from the piston 11b to the pressure transmission passage 33 side) via the pressure transmission passage 33.

By releasing the pressure accumulation state, the piston 11b in the negative pressure mechanism 11 is drawn toward the pressure transmission passage 33, so that the permeation side of the separation membrane 9a can be set to a lower pressure than the non-permeation side.
When the negative pressure storage unit 17 generates a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a, the valve 27 is opened.

  If at least one of the air high-pressure storage unit 15, the fuel high-pressure storage unit 16, and the negative pressure storage unit 17 described above is used, the separation between the non-permeation side and the permeation side of the separation membrane 9a can be achieved without using the pump 10. It is possible to separate a specific component in the raw fuel by generating a sufficient differential pressure. However, for the sake of simplicity, the differential pressure is generated using only the high-pressure storage 15 for air unless otherwise specified. An example will be described.

FIG. 6 shows a flowchart of control according to the present embodiment.
In step S1, it is determined whether the value obtained by subtracting the atmospheric pressure from the pressure Pha of the air high-pressure storage unit 15 (hereinafter referred to as the pressure accumulation amount Pacc) is less than Po.

The Po is the lower limit pressure accumulation amount that enables fuel separation according to the present invention, and is set as the lower limit value of the pressure accumulation amount Pacc that can perform fuel separation by the separation membrane 9a without any trouble.
If it is determined in step S1 that the pressure accumulation amount Pacc is equal to or greater than Po, it is determined that the pressure accumulation amount Pacc is within a range in which fuel separation by the separation membrane 9a can be performed without any trouble, and the process proceeds to step S2.

  On the other hand, if it is determined in step S1 that the pressure accumulation amount Pacc is less than Po, it is determined that the pressure accumulation amount Pacc is insufficient for performing fuel separation by the separation membrane 9a without any trouble, and the process proceeds to step S5. .

In step S2, it is determined whether the pressure accumulation amount Pacc is larger than Pa (Pa> Po).
The Pa is a predetermined pressure accumulation amount according to the present invention, and is set for determining whether the pressure accumulation amount Pacc is a sufficiently high value.

When it is determined in step S2 that the pressure accumulation amount Pacc is larger than Pa, it is determined that the pressure accumulation amount Pacc is a sufficiently high value, and the process proceeds to step S3.
On the other hand, when it is determined in step S2 that the pressure accumulation amount Pacc is equal to or less than Pa, it is determined that the pressure accumulation amount Pacc is within a range in which fuel separation by the separation membrane 9a can be performed without any hindrance, but the value is not sufficiently high. move on.

In step S4, it is determined whether the output We of the engine 1 is less than a predetermined output Wa.
Here, the predetermined output Wa can be set based on, for example, FIG.
FIG. 7 illustrates the relationship between the output of the engine 1 according to the present embodiment, the pressure storage efficiency of the high-pressure storage 15 for air, and the output of the pump 10.

  In FIG. 7, as the engine 1 has a lower output, the opportunity for stopping combustion of some cylinders to improve fuel consumption increases, and the pressure storage efficiency of the high pressure storage unit 15 for air is increased. Further, the higher the output of the engine 1 is, the higher the output of the pump 10 is.

  That is, it is advantageous to generate a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a by using the high pressure storage unit 15 for air whose pressure accumulation is promoted as the engine 1 has a lower output. The higher the output 1 is, the more advantageous it is to generate the differential pressure using the pump 10 whose output increases.

Therefore, the predetermined output Wa is set as a reference for determining which of the high pressure storage unit for air 15 or the pump 10 is advantageous for generating the differential pressure.
If it is determined in step S4 that the output We of the engine 1 is less than the predetermined output Wa, it is determined that it is more advantageous to generate the differential pressure by using the high pressure storage unit 15 for air, and step S3. Proceed to

  On the other hand, if it is determined in step S4 that the output We of the engine 1 is greater than or equal to the predetermined output Wa, it is determined that using the pump 10 is more advantageous for generating the differential pressure, and the process proceeds to step S5. .

In step S3, the specific component in the raw fuel is separated through the separation membrane 9a by generating a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a using the high pressure storage unit 15 for air. To do.
On the other hand, in step S5, the pump 10 is used to generate a differential pressure between the non-permeate side and the permeate side of the separation membrane 9a, thereby separating the specific component in the raw fuel through the separation membrane 9a.

  In FIG. 6, when the differential pressure between the non-permeate side and the permeate side of the separation membrane 9 a is generated using only the fuel high-pressure storage unit 16, the pressure accumulation amount Pacc is the fuel pressure Phf of the fuel high-pressure storage unit 16. Defined by subtracting the fuel pressure under atmospheric pressure from

Further, when the differential pressure is generated using only the negative pressure saving unit 17, the pressure accumulation amount Pacc is defined by a value obtained by subtracting the pressure Pla of the negative pressure saving unit 17 from the atmospheric pressure.
Furthermore, Po, Pa, and Wa are the case where the differential pressure is generated using only the high pressure storage unit 15 for air, the case where the differential pressure is generated using only the high pressure storage unit 16 for fuel, and the negative pressure In the case where the differential pressure is generated using only the storage unit 17, different values can be set.

  As described above, according to the present embodiment, the air compressed by the cylinder 41 that has stopped combustion during the reduced cylinder operation such as deceleration is taken into the high pressure storage unit 15 for air, and the high pressure storage unit 15 for air is accumulated. State.

  Further, by releasing the pressure accumulation state of the high-pressure storage 15 for air and driving the pumping mechanism 7, a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a is generated, and the fuel is separated by the separation membrane 9a. It can be performed.

  As described above, by using the cylinder 41 that is originally used for the operation of the engine 1, a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a can be generated, and the fuel can be separated by the separation membrane 9a. .

  Furthermore, a part of the kinetic energy of the piston of the cylinder 41 whose combustion has been stopped can be effectively used for separating the fuel by the separation membrane 9a without being discarded, and the fuel efficiency can be improved.

  When the fuel high-pressure storage unit 16 is in a pressure accumulation state, the high-pressure pump is generated by guiding the high fuel pressure in the common rail 42 to the fuel high-pressure storage unit 16 via the pressure transmission passage 35. A part of the energy (a part of the output of the engine 1) can be effectively used for fuel separation without being discarded.

Also, when the negative pressure storage unit 17 is in a pressure accumulation state, the intake negative pressure generated during deceleration or the like can be effectively used for fuel separation by guiding the intake negative pressure to the negative pressure storage unit 17.
Furthermore, according to the present embodiment, the separation membrane 9a is not permeated in accordance with the output We of the engine 1 and the pressure accumulation amount Pacc of the high-pressure storage unit 15 for air (or the high-pressure storage unit 16 for fuel, the negative pressure storage unit 17). The source of the differential pressure between the side and the permeate side can be switched between the pressure accumulator 3 and the pump 10.

  Therefore, even when the output of the engine 1 is too small, for example, and the pump 10 cannot sufficiently generate the differential pressure, the pressure accumulation device 3 generates the differential pressure sufficiently, which is sufficient for a wide range of operating conditions. Fuel separation can be performed stably at a speed.

  As a result, it is possible to more reliably avoid the fact that the fuel of one component becomes insufficient due to a decrease in the fuel separation speed, and the fuel supplied to the engine 1 is biased only to the other fuel, resulting in a decrease in exhaust properties and a decrease in output. , It is possible to more reliably prevent a reduction in fuel consumption.

Next, a second embodiment of the present invention will be described.
In the present embodiment, the pump 10 is configured to be electrically driven by being supplied with electric power from the battery 4.

FIG. 8 shows a flowchart of control according to the present embodiment.
In step S11, it is determined whether or not the pressure accumulation amount Pacc of the high pressure storage unit 15 for air is less than Po.

  When it is determined in step S11 that the pressure accumulation amount Pacc is equal to or more than Po, it is determined that the pressure accumulation amount Pacc is within a range in which fuel separation by the separation membrane 9a can be performed without any trouble, and the process proceeds to step S12.

  On the other hand, when it is determined in step S11 that the pressure accumulation amount Pacc is less than Po, it is determined that the pressure accumulation amount Pacc is insufficient for performing fuel separation by the separation membrane 9a without any trouble, and the process proceeds to step S15. .

In step S12, it is determined whether the pressure accumulation amount Pacc is larger than Pa (Pa> Po).
If it is determined in step S12 that the pressure accumulation amount Pacc is greater than Pa, it is determined that the pressure accumulation amount Pacc is a sufficiently high value, and the process proceeds to step S13.

  On the other hand, if it is determined in step S12 that the pressure accumulation amount Pacc is equal to or less than Pa, it is determined that the pressure accumulation amount Pacc is within a range in which fuel separation by the separation membrane 9a can be performed without hindrance, but the value is not sufficiently high, and the process proceeds to step S14 move on.

In step S14, it is determined whether the power generation amount ηe of the generator 5 is less than a predetermined value A.
Here, the predetermined value A can be set based on, for example, FIG.
FIG. 9 illustrates the relationship between the output of the engine 1 according to the present embodiment and the power generation amount ηe of the generator 5.

  In FIG. 9, the higher the engine 1 is, the higher the power generation amount ηe of the generator 5 is, and the charging efficiency of the battery 4 is increased, thereby increasing the power that can be supplied from the battery 4 to the pump 10. . Further, as described in the first embodiment, the pressure accumulation efficiency of the high pressure storage unit 15 for air increases as the engine 1 has a lower output.

  That is, it is advantageous to generate a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a by using the high pressure storage unit 15 for air whose pressure accumulation is promoted as the engine 1 has a lower output. The higher the output 1 is, the more the power generation amount ηe of the generator 5 increases and the remaining charge of the battery 4 can easily be afforded. Therefore, it is advantageous to generate the differential pressure using the pump 10.

Therefore, the predetermined value A is set as a reference for determining which of the high pressure storage unit for air 15 or the pump 10 is advantageous for generating the differential pressure.
When it is determined in step S14 that the power generation amount ηe of the power generator 5 is less than the predetermined value A, the power generation amount ηe of the power generator 5 is not sufficient to perform fuel separation. The use is judged to be advantageous for generating the differential pressure, and the process proceeds to step S13.

  On the other hand, when it is determined in step S14 that the power generation amount ηe of the power generator 5 is equal to or greater than the predetermined value A, the power generation amount ηe of the power generator 5 is sufficient to perform fuel separation, so the pump 10 is used. It is determined that this is more advantageous for generating the differential pressure, and the process proceeds to step S15.

  In step S13, the specific component in the raw fuel is separated through the separation membrane 9a by generating a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a using the high pressure storage unit 15 for air. To do.

On the other hand, in step S15, the pump 10 is used to generate a differential pressure between the non-permeate side and the permeate side of the separation membrane 9a, thereby separating the specific component in the raw fuel through the separation membrane 9a.
The Po, Pa, and A are the negative pressure when the differential pressure is generated using only the high-pressure storage unit 15 for air, the differential pressure is generated using only the high-pressure storage unit 16 for fuel, and the negative pressure. In the case where the differential pressure is generated using only the storage unit 17, different values can be set.

  As described above, according to the present embodiment, the separation membrane depends on the power generation amount ηe of the generator 5 and the pressure accumulation amount Pacc of the high pressure air storage unit 15 (or the fuel high pressure storage unit 16 and the negative pressure storage unit 17). The source of the differential pressure between the non-permeate side and the permeate side of 9a can be switched between the pressure accumulator 3 and the pump 10.

  Accordingly, even when the pump 10 cannot sufficiently generate the differential pressure due to, for example, the power generation amount ηe of the generator 5 being insufficient, the pressure accumulation device 3 can sufficiently generate the differential pressure, so that a wide range of vehicle conditions can be obtained. The fuel can be stably separated at a sufficient speed.

  As a result, it is possible to more reliably avoid the fact that the fuel of one component becomes insufficient due to a decrease in the fuel separation speed, and the fuel supplied to the engine 1 is biased only to the other fuel, resulting in a decrease in exhaust properties and a decrease in output. , It is possible to more reliably prevent a reduction in fuel consumption.

Next, a third embodiment of the present invention will be described.
The vehicle of this embodiment is a hybrid vehicle that travels with the output of at least one of the engine 1 or the motor.

For example, the motor may be configured such that the generator 5 can be driven as a motor and is driven by being supplied with driving power from the battery 4.
Further, the pump 10 is configured to be electrically driven as in the second embodiment.

FIG. 10 shows a flowchart of control according to the present embodiment.
In step S21, it is determined whether or not the pressure accumulation amount Pacc of the high pressure storage unit 15 for air is less than Po.

  When it is determined in step S21 that the pressure accumulation amount Pacc is equal to or greater than Po, it is determined that the pressure accumulation amount Pacc is within a range in which fuel separation by the separation membrane 9a can be performed without any trouble, and the process proceeds to step S22.

In step S22, it is determined whether the pressure accumulation amount Pacc is larger than Pa (Pa> Po).
When it is determined in step S22 that the pressure accumulation amount Pacc is greater than Pa, it is determined that the pressure accumulation amount Pacc is a sufficiently high value, and the process proceeds to step S23.

  On the other hand, when it is determined in step S22 that the pressure accumulation amount Pacc is equal to or less than Pa, it is determined that the pressure accumulation amount Pacc is within a range in which fuel separation by the separation membrane 9a can be performed without any hindrance, but the value is not sufficiently high. move on.

In step S24, it is determined whether the remaining charge SOC of the battery 4 is less than a second predetermined value B.
The second predetermined value B is set within a range in which overdischarge of the battery 4 can be sufficiently avoided even when the pump 10 is driven to sufficiently generate a differential pressure between the non-permeation side and the permeation side of the separation membrane 9a. It is good.

  When it is determined in step S24 that the remaining charge SOC of the battery 4 is less than the second predetermined value B, the remaining charge SOC of the battery 4 is not sufficient to perform fuel separation, so the high pressure storage unit for air 15 is judged to be advantageous for generating the differential pressure, and the process proceeds to step S23.

  On the other hand, when it is determined in step S24 that the remaining charge SOC of the battery 4 is equal to or greater than the second predetermined value B, the remaining charge SOC of the battery 4 is sufficient to perform fuel separation. It is determined that it is more advantageous to generate the differential pressure, and the process proceeds to step S25.

  If it is determined in step S21 that the pressure accumulation amount Pacc is less than the Po, it is determined that the pressure accumulation amount Pacc is insufficient for performing fuel separation by the separation membrane 9a without any trouble, and the process proceeds to step S26. .

In step S26, as in step S24, it is determined whether the remaining charge SOC of the battery 4 is less than the second predetermined value B.
If it is determined in step S26 that the remaining charge SOC of the battery 4 is less than the second predetermined value B, the remaining charge SOC of the battery 4 is not sufficient to perform fuel separation, and the accumulated pressure Pacc However, the fuel is not sufficiently separated by the separation membrane 9a without hindrance, so that the fuel is not separated by the high-pressure storage 15 for the air and the pump 10, and returns.

  On the other hand, when it is determined in step S26 that the remaining charge SOC of the battery 4 is equal to or greater than the second predetermined value B, the remaining charge SOC of the battery 4 is sufficient to perform fuel separation. Is used to determine that the differential pressure can be generated, and the process proceeds to step S25.

  In step S23, the differential component between the non-permeate side and the permeate side of the separation membrane 9a is generated by using the high pressure storage unit 15 for air to separate specific components in the raw fuel through the separation membrane 9a. To do.

On the other hand, in step S25, the pump 10 is used to generate a differential pressure between the non-permeate side and the permeate side of the separation membrane 9a, thereby separating the specific component in the raw fuel through the separation membrane 9a.
Note that Po, Pa, and B are generated when the differential pressure is generated using only the air high-pressure storage unit 15, when the differential pressure is generated only using the fuel high-pressure storage unit 16, and negative pressure. In the case where the differential pressure is generated using only the storage unit 17, different values can be set.

  Thus, according to the present embodiment, in the hybrid vehicle, according to the remaining charge SOC of the battery 4 and the pressure accumulation amount Pacc of the high pressure storage unit 15 for air (or the high pressure storage unit 16 for fuel, the negative pressure storage unit 17). Thus, the source of the differential pressure between the non-permeation side and the permeation side of the separation membrane 9a can be switched between the pressure accumulator 3 and the pump 10.

  Therefore, for example, even when the pump 10 cannot sufficiently generate the differential pressure because the remaining charge SOC of the battery 4 is insufficient, for example, the pressure accumulation device 3 generates the differential pressure sufficiently, so that a wide range of vehicle conditions can be obtained. The fuel can be stably separated at a sufficient speed.

  As a result, in the hybrid vehicle, it is possible to more reliably avoid the fact that the fuel of one component is insufficient due to the decrease in the fuel separation speed and the fuel supplied to the engine 1 is biased only to the other fuel. Further, it is possible to more reliably prevent a decrease in output and a decrease in fuel consumption.

Next, a fourth embodiment of the present invention will be described.
In the present embodiment, the fuel is separated by the pressure accumulating device 3 or the pump 10 when the engine 1 is stopped (including when the hybrid vehicle travels only by the motor).

The pump 10 is configured to be electrically driven as in the second and third embodiments.
FIG. 11 shows a flowchart of control according to the present embodiment.
In step S31, it is determined whether or not the pressure accumulation amount Pacc of the high pressure storage unit 15 for air is less than Po.

  If it is determined in step S31 that the pressure accumulation amount Pacc is equal to or more than Po, it is determined that the pressure accumulation amount Pacc is within a range in which fuel separation by the separation membrane 9a can be performed without any trouble, and the process proceeds to step S32.

  On the other hand, when it is determined in step S31 that the pressure accumulation amount Pacc is less than the Po, it is determined that the pressure accumulation amount Pacc is insufficient for performing fuel separation by the separation membrane 9a without any trouble, and the process proceeds to step S33. .

In step S33, it is determined whether the remaining charge SOC of the battery 4 is less than a third predetermined value C.
The third predetermined value C is set within a range in which overdischarge of the battery 4 can be sufficiently avoided even when the differential pressure between the non-permeation side and the permeation side of the separation membrane 9a is sufficiently generated by driving the pump 10. It is good.

  If it is determined in step S33 that the remaining charge SOC of the battery 4 is less than the third predetermined value C, the remaining charge SOC of the battery 4 is not sufficient to perform fuel separation, and the accumulated pressure Pacc However, the fuel is not sufficiently separated by the separation membrane 9a without hindrance, so that the fuel is not separated by the high-pressure storage 15 for the air and the pump 10, and returns.

  On the other hand, when it is determined in step S33 that the remaining charge SOC of the battery 4 is equal to or greater than the third predetermined value C, the remaining charge SOC of the battery 4 is sufficient to perform fuel separation. Is determined that the differential pressure can be generated, and the process proceeds to step S34.

  In step S32, the air high pressure storage unit 15 is used to generate a differential pressure between the non-permeate side and the permeate side of the separation membrane 9a, thereby separating the specific component in the raw fuel through the separation membrane 9a. To do.

On the other hand, in step S34, the pump 10 is used to generate a differential pressure between the non-permeate side and the permeate side of the separation membrane 9a, thereby separating the specific component in the raw fuel through the separation membrane 9a.
In addition, Po and C are the case where the differential pressure is generated using only the high pressure storage unit 15 for air, the case where the differential pressure is generated using only the high pressure storage unit 16 for fuel, and the negative pressure storage unit. In the case where the differential pressure is generated using only 17, different values can be set.

  As described above, according to the present embodiment, even when the engine 1 is stopped, the remaining charge SOC of the battery 4 and the high-pressure storage unit 15 for air (or the high-pressure storage unit 16 for fuel, the negative-pressure storage unit 17). The source of the differential pressure between the non-permeate side and the permeate side of the separation membrane 9a can be switched between the pressure accumulator 3 and the pump 10 according to the pressure accumulation amount Pacc.

  Therefore, for example, even when the pump 10 cannot sufficiently generate the differential pressure because the remaining charge SOC of the battery 4 is insufficient, the pressure accumulation device 3 generates the differential pressure sufficiently. Fuel separation can be performed stably at a sufficient speed in a wide range of vehicle conditions during a stop.

  In particular, since fuel separation is performed while the engine 1 is stopped, it is possible to more reliably prevent a shortage of fuel of a desired component when the engine 1 is restarted.

1 is a system configuration diagram according to the first embodiment of the present invention. Detailed view of fuel separator and pressure accumulator according to FIG. 2 is a detailed view of a pressure transmission path connecting the pressure accumulating device and the cylinder according to FIG. Detailed view of pressure transmission path connecting pressure accumulator and common rail according to FIG. Detailed view of pressure transmission path connecting pressure accumulator and master back according to FIG. The figure which shows the flowchart of the control which concerns on 1st Embodiment of this invention. The figure which shows the example of the relationship between an engine output, the pressure accumulation efficiency, and the output of a pump based on 1st Embodiment of this invention. The figure which shows the flowchart of the control which concerns on 2nd Embodiment of this invention. The figure which shows the example of the relationship between the output of an engine and the electric power generation amount of a generator based on 2nd Embodiment of this invention. The figure which shows the flowchart of the control which concerns on 3rd Embodiment of this invention. The figure which shows the flowchart of the control which concerns on 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 3 Pressure accumulator 5 Generator 4 Battery 9a Separation membrane 10 Pump 15 High pressure storage part 16 for air High pressure storage part 17 for fuel Negative pressure storage part 41 Cylinder 42 Common rail 43 Master back

Claims (15)

Mounted on the vehicle,
The raw fuel is supplied to the non-permeate side of the separation membrane, and a specific component is separated through the separation membrane by the differential pressure between the non-permeate side and the permeate side of the separation membrane. An engine fuel supply device that supplies an engine through different supply paths,
A fuel supply device for an engine, comprising: a pressure accumulating device that generates a differential pressure by releasing the pressure accumulating state according to a state of a vehicle while being accumulated by a rotational force of the engine. A pump capable of generating the differential pressure by driving;
Switching means for switching the source of the differential pressure between the pressure accumulator and the pump according to the state of the vehicle;
The fuel supply device for an engine according to claim 1, comprising: The pump is configured to be driven by an engine;
The switching means is
When the pressure accumulation amount of the pressure accumulator is higher than a predetermined pressure accumulation amount that is higher than the lower limit pressure accumulation amount capable of fuel separation, or the engine output is a predetermined output when the pressure accumulation amount of the pressure accumulator is not less than the lower limit pressure accumulation amount and not more than the predetermined pressure accumulation amount If lower,
The engine fuel supply device according to claim 2, wherein the pressure accumulator is a source of the differential pressure. The pump is configured electrically,
A generator that is driven by an engine to generate electric power, and an electric storage means that can charge the electric power generated by the generator and supplies electric power for driving to the pump,
The engine fuel supply device according to claim 2, wherein the switching unit switches a source of the differential pressure based on a power generation amount of the generator. The switching means is
When the pressure accumulation amount of the pressure accumulator is higher than a predetermined pressure accumulation amount higher than a lower limit pressure accumulation amount that allows fuel separation, or when the pressure accumulation amount of the pressure accumulator is greater than or equal to the lower limit pressure accumulation amount and less than or equal to the predetermined pressure accumulation amount Is less than the predetermined value,
The engine fuel supply device according to claim 4, wherein the pressure accumulator is a source of the differential pressure. The vehicle is a hybrid vehicle that runs with the output of at least one of an engine or a motor,
The pump is configured electrically,
A generator that is driven by an engine to generate electric power, and a power storage means that is capable of charging the electric power generated by the generator and supplies driving electric power to the pump and the motor,
The engine fuel supply device according to claim 2, wherein the switching means switches the source of the differential pressure based on a remaining charge amount of the power storage means. The switching means is
When the pressure accumulation amount of the pressure accumulator is higher than a predetermined pressure accumulation amount higher than a lower limit pressure accumulation amount that allows fuel separation, or when the pressure accumulation amount of the pressure accumulator is not less than the lower limit pressure accumulation amount and not more than the predetermined pressure accumulation amount, If the amount is less than the second predetermined value,
The engine fuel supply device according to claim 6, wherein the pressure accumulator is a source of the differential pressure.   The engine fuel supply device according to any one of claims 4 to 7, wherein at least one of the pressure accumulator and the pump can generate the differential pressure when the engine is stopped. Both the pressure accumulator and the pump can generate the differential pressure when the engine is stopped,
The switching means is when the engine is stopped.
When the pressure accumulation amount of the pressure accumulator is equal to or greater than the lower limit accumulator amount capable of fuel separation, the pressure accumulator is used as the source of the differential pressure,
9. The pump according to claim 8, wherein when the pressure accumulation amount of the pressure accumulator is lower than the lower limit pressure accumulation amount and the remaining charge amount of the power storage unit is equal to or greater than a third predetermined value, the pump is used as a source of the differential pressure. The fuel supply device for the engine described.   9. The switching device according to claim 2, wherein when the pressure accumulation amount of the pressure accumulating device is lower than a lower limit pressure accumulation amount at which fuel can be separated, the pump is used as a source of the differential pressure. The fuel supply device for an engine according to one.   The said pressure accumulator takes in the air compressed by the cylinder which stopped combustion in the reduced cylinder driving | running | working of an engine, and is made into a pressure accumulation state, It is any one of Claims 1-10 characterized by the above-mentioned. Engine fuel supply device.   12. The engine fuel supply device according to claim 1, wherein the pressure accumulating device is brought into a pressure accumulating state by guiding a pressure of fuel in a common rail.   The fuel supply device for an engine according to any one of claims 1 to 12, wherein the pressure accumulating device is brought into a pressure accumulating state by introducing an intake negative pressure.   14. The fuel supply device for an engine according to any one of claims 1 to 13, wherein a fuel to be supplied to the engine is selected from the separated fuels according to the operating state of the engine. .   The fuel supply device for an engine according to any one of claims 1 to 14, wherein the separation membrane transmits a specific component based on an octane number.

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