JP3960051B2 - Accumulated fuel injection system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an accumulator fuel injection system including a high-pressure supply pump that pressurizes fuel sucked into a pressurizing chamber through a pump control valve such as a fuel pressure feed amount control valve or a fuel injection pressure control valve and pumps the fuel to a pressure accumulating container. The present invention relates to a device, and particularly relates to improvement in reliability of interior parts of an electric pump control valve such as an electromagnetic type or an electric type.
[0002]
[Prior art]
Conventionally, in a common rail type fuel injection device known as a fuel injection device for a diesel engine, for example, a high pressure fuel is stored in a pressure storage container (common rail) common to each cylinder of the engine, and a fuel injection valve communicating with the common rail is used. High pressure fuel is injected and supplied to each cylinder at a predetermined timing. In addition, it is necessary for the common rail to continuously accumulate a common rail pressure corresponding to the fuel injection pressure. For this reason, high pressure fuel is pumped from a variable discharge amount type high pressure supply pump, and this fuel pumping amount is controlled. Thus, feedback control is performed on the fuel pressure (fuel injection pressure) in the common rail. Such a high-pressure supply pump is a fuel that is sucked into the pressurizing chamber in accordance with the pressurizing chamber that pressurizes the fuel by the reciprocating motion of the plunger and the opening degree (valve opening) of the fuel flow path to the pressurizing chamber A pump control valve (suction metering valve) capable of determining the amount.
[0003]
[Problems to be solved by the invention]
However, in the common rail fuel injection device having the pump control valve as described above, an engine key is inserted into a key cylinder in the vehicle compartment in the solenoid coil of the intake metering valve in order to improve engine startability. At the same time as turning the engine key from the OFF position to the IG position, that is, when the ignition switch is turned on (IG / ON) and energization is started, it is necessary to start the engine immediately when energizing the starter that starts the engine. The valve opening was set so that the fuel amount and the fuel injection pressure were obtained.
[0004]
However, in the control method of the valve opening degree of the intake metering valve at the time of starting the engine as described above, if the starter is not energized in the IG / ON state and left for a long time, the intake metering valve The solenoid coil temperature rises to a temperature above the guaranteed limit value (inhalation metering valve reliability limit value) that can guarantee the reliability of the interior components of the intake metering valve. The life of the rubber parts and the resin parts such as the insulating film of the solenoid coil) is greatly shortened.
[0005]
OBJECT OF THE INVENTION
An object of the present invention is to provide a pressure accumulation type fuel injection device capable of extending the life of internal components of a pump control valve so that the temperature of the pump control valve before starting the engine does not exceed a guaranteed limit value. There is.
[0006]
[Means for Solving the Problems]
According to the first aspect of the present invention, when energization is started to the pump control valve that adjusts the fuel injection pressure or the fuel pumping amount discharged from the high-pressure supply pump when energized, until a predetermined condition is satisfied, When the engine speed does not rise above a predetermined value (for example, cranking speed), the pump control valve temperature before starting the engine does not exceed the guaranteed limit value by prohibiting energization of the pump control valve. Therefore, the reliability of the internal parts of the pump control valve can be improved, and the life of the internal parts of the pump control valve can be extended.
[0007]
According to the second aspect of the present invention, the pump control valve is energized when the engine key is inserted into the key cylinder or when the engine key is turned from the OFF position to the IG position or the ACC position in the key cylinder. Or when the door lock equipped on the vehicle is unlocked from outside the vehicle. Thus, immediately after the driver or the occupant gets into the vehicle, the engine key is turned to the ST position to start energization of the starter, and the engine can be cranked, so that the engine can be started quickly.
[0008]
Further, according to the invention described in claim 1, the predetermined condition described above, the method comprising the predetermined time, the predetermined time from the start of the energization of the pump control valve before the start of the engine it is characterized in that a time until before the pump control valve temperature reaches assurance limit. Thereby, the conditions for starting energization of the pump control valve and the conditions for prohibiting energization of the pump control valve are clarified.
[0009]
Further, according to the invention described in claim 1, and if the rotational speed of the engine does not rise above a predetermined value, when the energization of the starter is not made, or the rotational speed of the engine is more than cranking speed This is characterized in that the engine does not rise or the engine is not started. As a result, a condition for prohibiting energization of the pump control valve for preventing the temperature of the pump control valve before starting the engine from exceeding the guaranteed limit value becomes clear.
[0010]
According to the invention described in claim 3 , the pump control valve is an intake metering valve that adjusts the amount of fuel sucked into the pressurizing chamber of the high-pressure supply pump, and the intake metering valve is energized. It is a normally open type (normally open type) electromagnetic valve whose valve opening is fully opened when stopped. As a result, in order to improve engine startability, energization of the intake metering valve is started at the same time as the engine key is turned on, and when the starter is energized, the fuel amount and fuel injection pressure required for starting the engine immediately The valve opening is set so as to be obtained. Therefore, immediately after the driver or the occupant gets into the vehicle, the engine key is turned to the ST position to start energization of the starter, and the engine is cranked, so that the engine can be started quickly.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
[Configuration of Example]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the invention will be described based on examples with reference to the drawings. Here, FIG. 1 is a diagram showing the overall structure of the common rail fuel injection system.
[0012]
A common rail fuel injection system according to this embodiment includes a common rail 2 as a pressure accumulating container for accumulating high-pressure fuel corresponding to fuel injection pressure supplied to each cylinder of an internal combustion engine (hereinafter referred to as an engine) 1 such as a multi-cylinder diesel engine. Then, a plurality of (four in this example) injectors 3 mounted on each cylinder of the engine 1 and a fuel to be sucked into the pressurizing chamber through a suction metering valve 6 described later are pressurized to the common rail 2. A supply pump 4 for pumping and an electronic control unit (corresponding to a fuel injection control device of the present invention: hereinafter referred to as ECU) 10 for electronically controlling a plurality of injectors 3 and the supply pump 4 are provided.
[0013]
The common rail 2 needs to continuously accumulate a common rail pressure corresponding to the fuel injection pressure, and for this purpose, a discharge port of a supply pump 4 that discharges high-pressure fuel through a fuel pipe (high-pressure fuel flow path) 11 and It is connected. The leaked fuel from the injector 3 and the leaked fuel from the supply pump 4 are returned to the fuel tank 5 through leak pipes (fuel return paths) 12, 13, and 14. A pressure limiter 16 is attached to a relief pipe (fuel return path) 15 from the common rail 2 to the fuel tank 5. The pressure limiter 16 is a pressure safety valve that opens when the fuel pressure in the common rail 2 exceeds the limit set pressure to keep the fuel pressure below the limit set pressure.
[0014]
The injector 3 of each cylinder is connected to the downstream ends of a plurality of branch pipes 17 branched from the common rail 2, and a fuel injection nozzle that injects high-pressure fuel accumulated in the common rail 2 into each cylinder of the engine 1, and this fuel An electromagnetic fuel injection valve including an electromagnetic valve or the like as an electromagnetic actuator that performs back pressure control of a nozzle needle accommodated in an injection nozzle. The fuel injection from the injector 3 of each cylinder to each cylinder of the engine 1 is electronically controlled by energizing the solenoid valve and stopping energization (ON / OFF). That is, the high-pressure fuel accumulated in the common rail 2 is injected into the cylinder of the engine 1 while the solenoid valve of the injector 3 is open.
[0015]
The supply pump 4 is a well-known feed pump (low-pressure supply pump: not shown) that pumps up fuel in the fuel tank 5 by rotating the pump drive shaft 22 as the crankshaft (crankshaft) 21 of the engine 1 rotates. Built in. Here, in this embodiment, a power transmission device 25 such as a belt is stretched between a crank pulley 23 assembled at the tip of the crankshaft 21 and a pump pulley 24 assembled at the tip of the pump drive shaft 22. ing. For this reason, the pump drive shaft 22 of the supply pump 4 rotates in synchronization with the crankshaft 21 of the engine 1.
[0016]
The supply pump 4 pressurizes fuel by a pump chamber into which fuel pumped up by a feed pump flows through a fuel pipe 19, a plunger (not shown) driven by a pump drive shaft 22, and a reciprocating motion of the plunger. It has a pressurizing chamber (plunger chamber). The supply pump 4 is a high-pressure supply pump (fuel supply pump) that pressurizes fuel sucked into the pressurizing chamber from the pump chamber via the suction metering valve 6 and pumps high-pressure fuel from the discharge port to the common rail 2. . A suction metering valve (SCV) 6 for adjusting the degree of opening of the fuel flow path is attached to the fuel flow path from the pump chamber to the pressurizing chamber of the supply pump 4.
[0017]
The suction metering valve 6 corresponds to the pump control valve of the present invention, and is pressurized from the pump chamber of the supply pump 4 by being electronically controlled by a pump drive signal from the ECU 10 via a pump drive circuit (not shown). A common rail pressure corresponding to the fuel injection pressure (fuel pressure) supplied from each injector 3 to the engine 1 is changed by a pump pressure control valve (a solenoid valve for adjusting the intake amount) that adjusts the intake amount of fuel sucked into the room. To do.
[0018]
The intake metering valve 6 of the present embodiment includes a valve (valve element) that changes the opening degree of the fuel flow path from the pump chamber of the supply pump 4 to the pressurizing chamber, and a pump drive signal (suction metering valve command value). Normally open type solenoid valve (pump) that has a solenoid coil (electromagnetic coil) for adjusting the valve opening according to the valve, and when the energization to the solenoid coil is stopped, the valve opening is fully opened Control valve). In this embodiment, in order to improve the startability of the engine 1, an engine key is inserted into the key cylinder in the vehicle compartment and the engine key is turned from the OFF position to the IG position in the solenoid coil of the intake metering valve 6. At the same time, that is, energization is started simultaneously with turning on the ignition switch (IG / ON). As a result, when the starter for starting the engine 1 is energized, the valve opening is set so that the fuel amount and fuel injection pressure necessary for starting the engine 1 can be obtained immediately.
[0019]
The ECU 10 includes a CPU that performs control processing and arithmetic processing, a memory such as a ROM and a RAM, an input circuit, an output circuit, a power supply circuit, an injector drive circuit (EDU), and a pump drive circuit. A microcomputer having a structure is provided. And the sensor signal from various sensors is comprised so that it may input into a microcomputer, after A / D-converting with an A / D converter.
[0020]
The ECU 10 includes an injection timing / injection amount determining means for determining an optimal injection timing (main injection start timing: θt) and a target injection amount (= injection period: Q) according to the operating conditions of the engine 1, an engine An injection pulse width determining means for calculating an injection pulse time (injection pulse width) corresponding to the operating condition 1 or fuel injection pressure (that is, common rail pressure) and target injection amount (Q), and an injector drive circuit (EDU) Injector drive means for applying a pulsed injector drive current (injection pulse) to the solenoid valve of the injector 3 of each cylinder.
[0021]
That is, the ECU 10 is based on engine operation information such as the engine rotation speed (hereinafter referred to as engine speed: NE) detected by the rotation speed sensor 31 and the accelerator opening (ACCP) detected by the accelerator opening sensor 32. A target injection amount (Q) is calculated and applied to the solenoid valve of the injector 3 of each cylinder according to the operating condition of the engine 1 or the injection pulse width calculated from the fuel injection pressure (that is, common rail pressure) and the target injection amount (Q). An injector driving current (injection pulse) is applied. As a result, the engine 1 is operated.
[0022]
Further, the ECU 10 calculates an optimal fuel injection pressure (that is, a target common rail pressure) according to the operating conditions of the engine 1 and drives the intake metering valve 6 of the supply pump 4 via the pump drive circuit. (SCV control means). That is, the ECU 10 is detected by engine operation information such as the engine speed (NE) detected by the rotational speed sensor 31 and the accelerator opening (ACCP) detected by the accelerator opening sensor 32, and further by the cooling water temperature sensor 33. The target common rail pressure (Pct) is calculated by taking into account the correction of the engine cooling water temperature (THW) or the fuel temperature (THF) detected by the fuel temperature sensor 34, and in order to achieve this target common rail pressure, the intake adjustment A pump drive signal (suction metering valve command value) is output to the solenoid coil of the valve 6.
[0023]
More preferably, a common rail pressure sensor (fuel injection pressure detecting means, fuel pressure detecting means) 35 for detecting a common rail pressure corresponding to the fuel injection pressure is attached to the common rail 2, and the common rail detected by the common rail pressure sensor 35 is detected. A pump drive signal (suction metering valve command value) to the suction metering valve 6 of the supply pump 4 is fed back so that the pressure (Pcr) substantially matches the target common rail pressure (Pct) determined by the operating conditions of the engine 1. It is desirable to control. It is desirable to control the intake metering valve command value (drive current value) to the intake metering valve 6 by duty control. Adjusting the on / off ratio (energization time ratio / duty ratio) of the pump drive signal per unit time according to the target common rail pressure (or target pump pumping amount) to change the valve opening of the intake metering valve 6 By using the duty control, high-precision digital control becomes possible.
[0024]
Here, in this embodiment, the target injection amount (Q) is obtained by using the rotation speed sensor 31, the accelerator opening sensor 32, the coolant temperature sensor 33, or the fuel temperature sensor 34 as the operation condition detecting means for detecting the operation condition of the engine 1. The injection timing (θt) and the target common rail pressure (Pct) are calculated, but other sensors (for example, an intake air temperature sensor, an intake pressure sensor, a cylinder discrimination sensor, an injection timing sensor, etc.) as operating condition detection means ), The target injection amount (Q), the injection timing (θt), and the target common rail pressure (Pct) may be corrected in consideration of the detection signal (engine operation information).
[0025]
[Control method of embodiment]
Next, a control method of the common rail fuel injection system of this embodiment will be briefly described with reference to FIGS. Here, FIG. 2 and FIG. 3 are flowcharts showing a control method of the common rail fuel injection system.
[0026]
First, it is determined whether or not the ignition switch is turned on (IG / ON) (step S1). When the determination result is YES, the engine speed (NE), the accelerator opening (ACCP), the engine coolant temperature (THW), the fuel temperature (THF), and the common rail pressure, which are engine parameters (engine 1 operating conditions). (Pcr) and the like are taken in (step S2).
[0027]
Next, it is determined whether or not an operation flag (fNE) for determining that the engine has been started is set (step S3). If this determination is YES, the process proceeds directly to step S5. When the determination result in step S3 is NO, that is, when the engine 1 is not started, whether or not the starter energization flag (fSTA) for determining that the starter is energized is turned on. Is determined (step S4). If this determination is NO, the process directly proceeds to step S15.
[0028]
If the determination result in step S4 is YES, that is, if the starter is energized, it is determined whether or not the engine speed (NE) is lower than the cranking speed (A). (Step S5). If this determination is YES, the process proceeds directly to step S15. If the determination result in step S5 is NO, that is, if the engine speed (NE) is higher than the cranking speed (A), the counter that counts the time after IG · ON is cleared ( Step S6). Next, the operation flag (fNE) of the engine 1 is set (step S7).
[0029]
Next, it is determined whether or not the engine 1 has been started. Specifically, it is determined whether or not the engine speed (NE) is higher than the idle speed (B) (step S8). If the determination result is NO, that is, if the engine 1 has not been started, it is determined that the engine 1 is being cranked, and the SCV control amount (ΣDscv: intake metering valve command value) is It is set to the second fixed value (D2) during energization of the starter (during cranking) (step S9).
[0030]
Next, the target injection amount (Q) and the injector injection pulse width (Tq), which are INJ control amounts, are calculated based on the engine parameters. Further, the injection timing (θt) is calculated based on the engine parameter. Specifically, the target injection amount (Q) is obtained from the aforementioned engine speed (NE) and the aforementioned accelerator opening (ACCP). Further, the injector injection pulse width (Tq) is obtained from the aforementioned target injection amount (Q) and the aforementioned common rail pressure (Pcr). Further, an injection timing (θt) is obtained from the engine speed (NE) and the target injection amount (Q) (step S10).
[0031]
Next, the INJ control amount, the injection timing, and the SCV control amount are set in the output stage of the ECU 10. Specifically, the injector (INJ) injection pulse width (Tq) and the injection timing (θt) are set in the output stage of the ECU 10. Further, the SCV control amount (intake metering valve control command value: ΣDscv) is set in the output stage of the ECU 10 (step S11). Thereafter, the process returns to step S1, and the above control is repeated.
[0032]
If the determination result in step S8 is YES, that is, if the engine 1 has been started, the target common rail pressure (Pct) is calculated based on the engine parameters. Specifically, the target common rail pressure (Pct) is obtained from the engine speed (NE) and the target injection amount (Q) (step S12). Next, the SCV correction amount (Di) is calculated according to the pressure deviation (Pcr−Pct) between the common rail pressure (Pcr) and the target common rail pressure (Pct) (step S13). Next, the SCV correction amount (Di) is added to the previous SCV control amount (ΣDscv) to calculate the current SCV control amount (suction adjustment valve control command value: ΣDscv) (step S14). Thereafter, the process proceeds to step S10.
[0033]
If the determination result in step S4 is NO or if the determination result in step S5 is YES, the operation flag (fNE) of the engine 1 is canceled (step S15). Next, the elapsed time after IG · ON is counted up as CIGon = CIGon + 1 (step S16). Next, it is determined whether or not a predetermined time (T0) has passed since turning on the ignition switch (CIGon> T0) (step S17). If the determination result is NO, that is, if the predetermined time (T0) has not elapsed since the ignition switch was turned on, the intake metering valve 6 of the supply pump 4 is energized before the engine 1 is started. It is determined that the predetermined time (T0) has not elapsed since the start, and the SCV control amount (ΣDscv: intake metering valve command value) is set to the first fixed value (D1) before the start of energization to the starter (Step S18). Next, thereafter, the injector injection pulse width (Tq) that is the INJ control amount is cleared (step S19). Thereafter, the process proceeds to step S11.
[0034]
If the determination result in step S17 is YES, that is, if a predetermined time (T0) has elapsed since the ignition switch was turned on, the intake pump 4 performs the intake metering before the engine 1 is started. It is determined that a predetermined time (T0) has elapsed since the start of energization of the valve 6, and the SCV control amount (ΣDscv: intake metering valve command value) is reset (step S20). Thereafter, the process proceeds to step S19.
[0035]
If the determination result in step S1 is NO, the operation flag (fNE) of the engine 1 is canceled (step S21). Next, the counter (CIGon) for counting the time after IG · ON is cleared (step S22). Thereafter, the process proceeds to step S20.
[0036]
[Features of Example]
Next, the operation of the common rail fuel injection system according to this embodiment will be briefly described with reference to FIGS. Here, FIG. 4 is a timing chart showing the operation of the common rail fuel injection system.
[0037]
When an occupant gets into the vehicle, inserts an engine key into the key cylinder in the passenger compartment, and turns the engine key from the OFF position to the IG position in the key cylinder, the ignition switch is turned on (IG / ON), and the ECU 10 changes to FIG. And the routine of FIG. 3 is started (ECU • ON). Here, the solenoid coil of the suction metering valve 6 of the supply pump 4 starts energization with the first fixed value (D1) simultaneously with IG · ON, and the fuel necessary for starting the engine 1 immediately when the starter is energized. The valve opening is set so that the amount and the fuel injection pressure can be obtained.
[0038]
When the occupant turns the engine key from the IG position to the ST position in the key cylinder, energization (STA / ON) to the starter is started and the engine 1 is cranked. The solenoid coil of the suction metering valve 6 of the supply pump 4 starts energization with a second fixed value (D2) that is larger than the first fixed value (D1) simultaneously with STA · ON. Become. Since the supply pump 4 is driven at the cranking speed, fuel is pumped into the common rail 2 and the common rail pressure rises from the atmospheric pressure. At this time, since the fuel injection from the injector 3 of each cylinder to each cylinder of the engine 1 is performed, the engine 1 is started and the engine 1 is operated at an engine speed equal to or higher than the idle speed.
[0039]
However, when the starter is not energized in the IG / ON state and left for a long time, the drive current value to the solenoid coil of the suction metering valve 6 of the supply pump 4 is one point in the timing chart of FIG. As indicated by the chain line, when the first fixed value (D1) is maintained so as to maintain the predetermined valve opening, the solenoid coil temperature of the intake metering valve 6 of the supply pump 4 is changed to the timing shown in FIG. As indicated by the alternate long and short dash line in the chart, the temperature may rise to a temperature equal to or higher than a guarantee limit value (suction metering valve reliability limit value) that can guarantee the reliability of the interior parts of the supply pump 4. In this case, there is a problem that the service life of the interior parts of the intake metering valve 6 (for example, rubber parts such as sealing materials and resin parts such as solenoid coil insulating films) is significantly shortened.
[0040]
Therefore, in this embodiment, even when the starter is not energized in the IG / ON state and left for a long time, the suction pump of the supply pump 4 is temporarily adjusted after a predetermined time has elapsed since the IG / ON. The energization of the solenoid coil of the quantity valve 6 is prohibited (stopped). Thereafter, when the occupant turns the engine key from the IG position to the ST position in the key cylinder, that is, at the same time as STA / ON, the first fixed value (D1) is applied to the solenoid coil of the suction metering valve 6 of the supply pump 4 The startability of the engine 1 is compensated for by starting energization with a second fixed value (D2) that is larger than that.
[0041]
[Effect of Example]
As described above, the common rail fuel injection system according to the present embodiment does not start energization of the starter in the IG / ON state, but is left for a long time, when a predetermined time has elapsed since the IG / ON. Once, the energization of the solenoid coil of the suction metering valve 6 of the supply pump 4 is prohibited (stopped). That is, when the energization time to the solenoid coil of the intake metering valve 6 before the start of the engine 1 is longer than a predetermined time, the energization to the solenoid coil of the intake metering valve 6 is cut off so that the energization is more than necessary. The rise in the solenoid coil temperature of the intake metering valve 6 due to the above can be suppressed.
[0042]
As a result, the solenoid coil temperature of the suction metering valve 6 of the supply pump 4 does not exceed the guaranteed limit value (suction metering valve reliability limit value) as shown by the solid line in the timing chart of FIG. Therefore, the reliability of the interior parts of the suction metering valve 6 can be improved, and the lifetime of the interior parts of the suction metering valve 6 (for example, rubber parts such as sealing materials and resin parts such as solenoid coil insulation films) is improved. Becomes longer.
[0043]
Here, the energization time to the solenoid coil of the intake metering valve 6 before starting the engine 1 includes the outside air temperature, the engine cooling water temperature, the engine lubricating oil temperature, the fuel temperature sucked into the pressurized chamber of the supply pump 3, the supply It includes at least one of the leak fuel temperature of the pump 4, the battery voltage, the solenoid coil temperature of the suction metering valve 6, the drive current value to the solenoid coil of the suction metering valve 6, and the energization time of the glow plug. It should be noted that the lower the outside air temperature, the engine coolant temperature, the engine lubricating oil temperature, the fuel temperature, the lower the battery voltage, the lower the solenoid coil temperature of the intake metering valve 6, or the lower of the intake metering valve 6. As the drive current value to the solenoid coil is smaller, the energization time (predetermined time) to the solenoid coil of the intake metering valve 6 before starting the engine 1 may be lengthened.
[0044]
[Modification]
In this embodiment, the example in which the intake metering valve (suction amount adjusting electromagnetic valve) 6 for changing (adjusting) the amount of fuel sucked into the pressurizing chamber of the supply pump 4 has been described. A discharge amount adjusting electromagnetic valve for changing (adjusting) the fuel amount from the pressurizing chamber to the common rail 2 may be provided. In addition, a motor-driven (electric) suction metering valve may be provided instead of the electromagnetic valve.
[0045]
In this embodiment, a normally open type (normally open type) intake metering valve (inhalation amount adjusting electromagnetic valve) 6 that is fully opened when the energization of the solenoid valve is stopped is used. A normally open type (normally open type) discharge amount adjusting electromagnetic valve that is fully open when the valve opening degree stops energizing the electromagnetic valve may be used. Also, a normally closed type (normally closed type) solenoid valve that is fully closed when the valve opening of the discharge amount adjusting solenoid valve or the suction amount adjusting solenoid valve stops energizing the solenoid valve may be used. good.
[Brief description of the drawings]
FIG. 1 is a schematic view showing the overall structure of a common rail fuel injection system (Example).
FIG. 2 is a flowchart showing a control method of the common rail fuel injection system (Example).
FIG. 3 is a flowchart showing a control method of the common rail fuel injection system (Example).
FIG. 4 is a timing chart showing the operation of the common rail fuel injection system (Example).
[Explanation of symbols]
1 Engine 2 Common rail (accumulation vessel)
3 Injector (fuel injection valve)
4 Supply pump (high pressure supply pump)
6 Suction metering valve (pump control valve)
10 ECU (fuel injection control device)

Claims (3)

(A) a pressure accumulating container for accumulating high-pressure fuel corresponding to the fuel injection pressure;
(B) a fuel injection valve that injects and supplies the high-pressure fuel stored in the pressure storage container to each cylinder of the engine;
(C) a high-pressure supply pump that pressurizes and sucks the fuel to be sucked into the pressure accumulating container;
(D) a pump control valve that adjusts a fuel injection pressure or a fuel pumping amount discharged from the high-pressure supply pump when energized;
(E) a fuel injection control device that controls a valve opening of the pump control valve so as to obtain a fuel injection pressure or a fuel pumping amount that is set according to an operating condition of the engine ;
The fuel injection control device prohibits the energization of the pump control valve when the engine speed does not increase above a predetermined value until the predetermined condition is satisfied after the energization of the pump control valve is started. An accumulator fuel injection device,
The case where the rotational speed of the engine does not increase above a predetermined value means that the starter that starts the engine is not energized, the rotational speed of the engine does not increase above the cranking speed, or the engine If no start is made,
The predetermined condition is a predetermined time,
The predetermined time is a time from when energization of the pump control valve is started to before the temperature of the pump control valve before starting the engine reaches a guaranteed limit value. . The pressure accumulation type fuel injection device according to claim 1,
When the engine key for starting the engine is inserted into the key cylinder, or when the engine key is turned from the OFF position to the IG position or the ACC position in the key cylinder, Alternatively, the pressure accumulation type fuel injection device is started when the door lock provided in the vehicle is unlocked from outside the vehicle. In the pressure accumulation type fuel injection device according to claim 1 or 2 ,
The pump control valve is an intake metering valve that adjusts an amount of fuel sucked into a pressurizing chamber of the high-pressure supply pump;
The pressure-accumulating fuel injection device, wherein the intake metering valve is a normally-open electromagnetic valve whose valve opening is fully opened when energization is stopped.

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