JPH1061468A - Control method of accumulator type fuel supply system for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control method of an accumulator type fuel supply system for an engine which can perform a first explosion quickly after an engine starts. SOLUTION: A fuel is supplied from a high pressure fuel supply pump 104 to a common rail 105, and the fuel is supplied from the common rail 105 for storing a high pressure fuel to an injector 106. At the time of engine start, a duty control is performed to the high pressure fuel supply pump 104 when a start signal is input, and thereafter the high pressure fuel supply pump 104 is then subjected to a normal operation control when a cylinder discrimination is terminated. The fuel in the injector 106 is infected at plural times per one cycle for a period from an input of an engine starting signal to an input of an engine start termination signal. Accordingly, a pressure in the common rail after engine start is early started up to improve an fuel infection characteristic, resulting in that a startability of the engine is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply system for an engine for supplying high-pressure fuel from a high-pressure fuel supply pump to an injector via a pressure-accumulating common rail.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Utility Model Laid-Open No. 5-1854 and Japanese Unexamined Patent Publication No. Hei 7-158536, fuel supply for supplying high-pressure fuel from a high-pressure fuel supply pump to an injector via a pressure-accumulating common rail. In a system, a fuel supply device that connects a pressure control valve to a common rail is known. In such a fuel supply device, when the fuel pressure in the common rail rises above a predetermined pressure, the pressure control valve opens to discharge fuel from the common rail and regulate the fuel pressure of the common rail to a predetermined pressure or less. .

[0003] The pressure control valve for controlling the common rail pressure of the accumulator type fuel supply device is conventionally a mechanical type, and there is no known device for opening and closing control by an electric signal.

[0004]

According to the present applicant, a fuel supply device for electrically controlling the pressure in a common rail in order to remove air and fuel vapor generated in a fuel supply system when the engine is restarted at a high temperature. Has been proposed. In this type of accumulator fuel supply device for an engine, the start of the engine is completed when the internal pressure of the common rail is sufficiently high after the start of the engine. Therefore, the engine enters a stable normal operation state with the common rail internal pressure sufficiently high. For this reason, if the time when the internal pressure of the common rail reaches a predetermined value is defined as the time of completion of engine start, in the pressure accumulating type fuel supply device for the engine, compared to a normal fuel supply device without the common rail, the engine starts after the start of the engine. Until completion, the unstable operation state of the engine continues for a relatively long time. In an engine equipped with this kind of accumulator type fuel supply device, the period until the start of the engine tends to be long, and there is a great demand for shortening the period until the engine becomes stable.

In a conventional pressure-accumulation fuel supply system equipped with a high-pressure fuel injection pump, a drive pulse for opening and closing the injector after the start of the engine, for example, after the starter is turned on, is applied to each cylinder for intake, compression and combustion of the engine. And once every cycle consisting of exhaust and exhaust. For this reason, from the viewpoint of the easiness of combustion of the air-fuel mixture in the combustion chamber, it is not possible to form an air-fuel mixture that is uniform and easy to burn in a short period of time. It took a long time to complete the start until the internal pressure of the common rail was sufficiently increased, and it was not possible to avoid instability in the operating state until the start of the engine. It was not done enough.

An object of the present invention is to provide a method of controlling an accumulator type fuel supply system for an engine, in which the first explosion is performed immediately after the start of the engine to complete the start. Another object of the present invention is to provide a control method of an accumulator fuel supply device for an engine, which shortens a period from the start of engine start to completion of engine start, prolongs life by reducing load on a starter, and improves fuel efficiency. is there.

Another object of the present invention is to provide a method for controlling a pressure-accumulating fuel supply system for an engine, in which the pressure in a common rail is raised at an early stage after the engine is started, fuel injection characteristics are improved, and engine startability is improved. To provide.

[0008]

According to a control method of an accumulator type fuel supply system for an engine, the injector performs one cycle of fuel injection during a period from the input of an engine start start signal to the input of an engine start completion signal. Inject multiple times per shot. Therefore, in order to shorten the cranking period from the start of the engine to the first explosion or the period from the first explosion to the completion of the start until the internal pressure of the common rail is sufficiently increased, a stable normal operation state is established early after the start of the engine. Can be migrated.

According to a second aspect of the present invention, the low pressure fuel supply pump is driven when the engine start prediction signal is inputted prior to the input of the engine start start signal. Can be completed even earlier. According to the control method of the accumulator-type fuel supply device for an engine according to the third aspect, the engine start start signal is one of a starter-on signal, a low-pressure fuel supply pump-on signal, and an ignition key-on signal. Can be controlled electronically.

According to the control method of the accumulator type fuel supply device for an engine, the engine start completion signal is a predetermined value detection signal of a common rail pressure of a pressure sensor for detecting the pressure of the fuel supply system, and a predetermined engine speed. Since it is one of the value signals, the completion of the start of the engine can be accurately detected, and the subsequent normal operation can be appropriately shifted. According to the control method of the accumulator-type fuel supply device for an engine according to the fifth aspect, even when the phase of the starting cam cannot be calculated, the pressure of the accumulator in the common rail can be effectively increased quickly.

According to the control method of an accumulator fuel supply system for an engine according to the present invention, the start of the engine can be completed earlier in combination with the shortening of the starting period due to the promotion of fuel and the early rise of the pressure of the accumulator. Can be.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIGS. 1 to 5 show a first embodiment of the present invention. FIG. 1 is a system configuration diagram in which the fuel supply device of the present invention is applied to a fuel supply system for a gasoline engine.
The pressure of the fuel pumped from the fuel tank 100 by the low-pressure fuel supply pump 101 and supplied to the high-pressure fuel supply pump 104 via the filter 102 is adjusted to 0.2 to 0.5 MPa by the low-pressure pressure regulator 103. . High pressure fuel supply pump 104 from suction valve 104a
The fuel sucked into the pump is boosted to several MPa to several tens MPa and sent out from the delivery valve 230 to the common rail 105. The valve opening pressure of the suction valve 104a and the discharge valve 104b is set lower than the fuel supply pressure of the low-pressure fuel supply pump 101.

The high-pressure fuel supplied under pressure by the high-pressure fuel supply pump 104 and supplied to the common rail 105 is accumulated in a pressure accumulating chamber (not shown) formed in the common rail 105 and is supplied to an injector 106 provided in each cylinder of the engine. Supplied. The fuel pressure in the accumulator is detected by a pressure sensor 107 attached to the common rail 105, and the ECU detects the fuel pressure.
A pressure signal is sent to 110. The common rail 105 is further provided with a high pressure regulator 10 as a pressure control valve.

When the high pressure regulator 10 opens, the fuel in the accumulator is discharged to the fuel tank 100, and the fuel pressure in the accumulator is adjusted. The ECU 110 receives an ignition (Ig) signal, a starter (STA) signal, and an engine speed (NE) signal from various sensors, in addition to the pressure signal from the pressure sensor 107, and grasps the engine operating state.

Next, the high pressure regulator 10 will be described in detail with reference to FIG. The high-pressure pressure regulator 10 can be mechanically opened according to the pressure difference between the inlet and the outlet, or can be forcibly opened by inputting an electric signal electromagnetically regardless of the pressure difference between the inlet and the outlet. Housing 1 for high pressure regulator 10
One end of the housing 11 is caulked and fixed to the valve body 12, and the other end of the housing 11 is caulked and fixed to the fixed core 21. A filter case 13 is inserted into the fuel suction side of the valve body 12, and a fuel filter 14 is accommodated in the filter case 13. Male screw portion 11a provided on the outer peripheral wall at the center of housing 11
Is screw-connected to a female screw portion (not shown) of the common rail 105 so that the high-pressure pressure regulator 10 is attached to the common rail 105.

The needle valve 15 is accommodated in the valve body 12 so as to be able to reciprocate. A contact portion 15a, which is one end of the needle valve 15, can be seated on a valve seat 12a provided on the nozzle body 12. . A fixed portion 15b which is the other end of the needle valve 15 is fixed to the movable core 22 by laser welding or the like. A spacer 16 is provided between the nozzle body 12 and the housing 11, and the thickness of the spacer 16 is adjusted to control the needle valve 1
5 can be adjusted.

The fixed core 21 is fixed to the housing 11 by caulking, and a connector 40 is molded on the outer peripheral wall of the fixed core 21 including the caulked portion. The adjusting pipe 31 is caulked and fixed to the fixed core 21 by being pressed into the fixed core 21. By adjusting the pushing amount of the adjusting pipe 31, the urging force of the compression coil spring 34 can be adjusted. The urging force of the compression coil spring 34 is set to be larger than the force that the needle valve 15 receives in the valve opening direction from the fuel supply pressure of the high-pressure fuel supply pump 104.

Fixed core 21, movable core 22, coil 35
Constitutes an electromagnetic drive unit. A coil 35 wound around a spool 36 is provided on the outer periphery of the fixed core 21, and power is supplied to the coil 35 from a terminal 41 provided on the connector 40. The movable core 22 is supported by the housing 11 so as to be reciprocally movable, and is urged by a compression coil spring 34 in the valve seating direction of the needle valve 15.

Next, the operation of the electromagnetic pressure regulator will be described with reference to FIGS. When the coil 35 is energized, as shown in FIG. 3, the movable core 22 abuts on the fixed core 21 so that the contact portion 1
5a are separated, and the high-pressure fuel on the common rail side is
4 through the inside of the adjusting pipe 31 to the low pressure side. Thereby, the pressure inside the common rail 105 drops.

When the coil 35 is de-energized, the position of the needle valve 15 is determined according to the balance between the pressure on the common rail side, the pressure inside the adjusting pipe 31, and the set pressure of the compression coil spring 34. If the pressure on the common rail side is lower than the set pressure of the compression coil spring 34, the contact portion 15a of the contact portion 15 of the needle valve 15 contacts the valve seat 12a. When the pressure on the common rail side exceeds the set pressure of the compression coil spring 34, the needle valve 15
As shown in FIG. 4, the high-pressure fuel on the common rail side passes through the fuel passage 24 and the fuel passage 25 in the gap between the periphery of the movable core 22 and the inner wall of the housing 11 as shown in FIG. Street, escape to the low pressure side. Thus, when the common rail pressure rises excessively, the common rail pressure is maintained at the set pressure.

The opening area of the seat 15a of the needle valve 15 and the opening of the valve seat 12a of the nozzle body 12 due to the lift of the valve 15 change after the opening due to the common rail pressure. The sum of the flow path areas of the flow paths 24 and 25 is set to be larger than the area between the seat 15a and the valve seat 12a. As a result, the needle valve 15 is lifted when the common rail pressure rises abnormally, so that the amount of pressure relief increases in accordance with the lift amount.

As shown in FIG. 5, the high-pressure fuel supply pump 1
04 is a cylinder 211 containing an inlet 212, an electromagnetic valve 220 as a metering valve, and a delivery valve 230.
Is fixed to a head cover 200 which is a part of the engine housing. The other part of the high-pressure fuel supply pump 104 housed in the head cover 200 is housed in a sleeve housing hole 276 of the head cover 200 surrounded by a cylindrical sleeve 240. Sleeve 24
0 is fixed to the cylinder 211 by a screw screw 260. The pump cam 111 is attached to a valve cam shaft that opens and closes an intake valve or an exhaust valve of the engine, and drives a plunger 243.

An annular fuel reservoir 211 is provided on the inner wall of a cylinder 211 for supporting the plunger 243 in a reciprocating manner.
b and 211c are formed. Fuel pool 211
b communicates with the suction passage 212a via the return passage 217, and the fuel reservoir 211c communicates with a return passage (not shown). A suction passage 212a is formed in the suction port 212, and fuel is supplied from the low-pressure fuel supply pump 101. The intake passage 212a communicates with the fuel passage 213, and communicates with the fuel reservoir 211b via the return passage 217.

The solenoid valve 220 is vertically inserted into the cylinder 211, and a valve body 222 having a fuel supply passage is inserted inside the solenoid valve 220. The valve body 223 is disposed on the valve body 222 so as to be able to contact and separate from the valve seat 221. Further, the valve element 223 is urged downward by a spring as an urging means (not shown).
When the power is supplied, the valve body 223 moves upward against the spring force, so that the solenoid valve is closed by contacting the valve seat 221. The spring is set to a biasing force for closing the valve seat 221 by the valve body 223 when the plunger 243 rises and the pressure in the fuel pressurizing chamber 216 described later rises. The −Z-axis end face of the valve body 222 is a plate 224, the −Z-axis end face of the plate 224 is a washer 225, and the −Z of the washer 225.
The axial end face is in surface contact with the cylinder 211. An annular fuel gallery 214 is formed on the inner wall of the cylinder 211 around the solenoid valve 220, and the fuel gallery 214 communicates with the fuel passage 213 and the fuel pressurizing chamber 216.

The delivery valve 230 is fixed to the cylinder 211 by screw connection, and the discharge valve body 231 is urged to a valve seat 233 by a compression coil spring 232. When the pressure in the fuel pressurizing chamber 216 exceeds a predetermined pressure, the discharge valve body 231 lifts against the urging force of the compression coil spring 232, and the discharge passage 215 and the discharge port 234 communicate with each other.
Discharge the fuel. The delivery valve 230 is connected to the common rail 105 by a fuel pipe (not shown).

The tappet 241 is formed in a cylindrical shape with a bottom.
The bottom surface 241a is in contact with the pump cam 111. The tappet 241 is slidably supported on the inner wall 240b of the sleeve 240. A cylindrical oil reservoir 242 is provided between the inner wall 240b of the sleeve 240 and the outer wall of the tappet 241.
Are formed, an oil passage 201 formed in the head cover 200, and an oil through hole 240 formed in the sleeve 240.
The lubricating oil is supplied through the line a to prevent seizure with the sleeve 240 due to the reciprocation of the tappet 241. The tappet 241 does not lock on the pin 261 even at the bottom dead center position of the plunger 243 shown in FIG. 5, but is prevented from dropping by the pin 261 when assembled to the head cover 200.

The plunger 243 is slidably supported in the axial direction on the inner wall of the cylinder 211 forming the sliding hole 211a. The spring seat 244 is urged in the −Z-axis direction in FIG. 5 by the compression coil spring 245 and is in contact with the inner bottom surface of the tappet 241. Plunger 243
The head portion 243a is sandwiched between the inner bottom surface of the tappet 241 and the spring seat 244, and is urged by the spring seat 244 in the −Z-axis direction in FIG. A fuel pressurizing chamber 216 is formed by the end face of the plunger 243 in the + Z axis direction in FIG. 5, the inner wall of the cylinder 211, and the end face of the solenoid valve 220.

The ECU 110 determines the energization timing of the solenoid valve 220 so that the fuel injection pressure becomes an optimum value according to the pressure signal detected by the pressure sensor 107 and the engine operation state such as the engine speed and load. By controlling, the amount of fuel discharged to the common rail 105 is controlled. That is, by energizing at some point during the time when the plunger 243 moves from the bottom dead center to the top dead center, the solenoid valve is closed and the fuel pressurizing chamber 216 is closed. Then plunger 24
3 continues to rise, and when the delivery valve 230 reaches a predetermined pressure, the discharge valve body 231 lifts and the fuel is supplied to the common rail 1.
Start discharging at 05. Until the plunger 243 reaches the top dead center, the fuel in the fuel pressurizing chamber 216
5, the longer the time from the start of discharge to the common rail 105 until the plunger 243 reaches the top dead center, the more the amount of fuel is sent to the common rail 105. Therefore, by controlling the energization timing, the amount of fuel sent to the common rail 105 can be controlled, and the pressure in the common rail can be controlled.

The ECU 110 includes sensors 108.
, An engine operating state such as an engine speed and a load state is detected, and a control signal for controlling a fuel injection timing and an injection period is output to the injector 106 in accordance with the detected operating state. Here, the sensors include, for example, an accelerator opening signal or an upshift signal of an automatic transmission. Based on such a detection signal, a request to reduce the pressure in the common rail from the engine is determined, and the closing timing of the solenoid valve 220 of the high-pressure fuel pump 104 and the opening and closing of the electromagnetic pressure regulator 112 are controlled to control the opening and closing of the common rail. Controlling pressure.

Next, the control of the high-pressure pump and the control of the injector during the start control of the engine according to the present embodiment will be described with reference to FIG.
It will be described based on. (1) Start prediction When a start prediction signal for predicting start of engine start is input, the low-pressure fuel supply pump 101 is turned on. That is, before the engine key switch is turned on, the low-pressure fuel supply pump 101 is quickly turned on to supply the low-pressure fuel to the pressure accumulating type common rail 105 at an early stage, and then to quickly shift to a normal operation state after the starter is turned on. That's why. Here, the start prediction signal is a time when a behavior pattern of a driver with a high probability of starting the engine is detected. For example, switching of the vehicle driver's seat from the door closed mode to the door open mode, detection of door key insertion, and the like.

(2) Starter motor start When the starter motor is started by turning on the engine key switch, the duty control of the high-pressure fuel supply pump 104 is started. This duty control is to increase the common rail pressure at an early stage by the duty control of the solenoid valve 220 which is a metering valve for the discharge amount of the high-pressure fuel supply pump 104, and is executed at a stage where the cylinder discrimination of the engine is not established. The process is continued until the cylinder discrimination is established. Here, the establishment of the cylinder discrimination means that the phase of the pump cam 111 is calculated thereby, and the discharge amount of the pump is controlled by controlling the metering valve. That is, in a state where the cylinder discrimination is not established, that is, in a state where the phase of the cam cannot be calculated, the phase of the pump cam 111 is unknown, and the discharge amount cannot be controlled. Increase pressure early. That is, if duty control is performed to open and close the electromagnetic valve 220 at minute intervals regardless of the phase of the pump cam 111, when the plunger rises due to the rotation of the pump cam, the electromagnetic valve 220
Even when no power is supplied to the valve, the valve body 223 abuts on the valve seat 221 against the urging means due to the pressure increase in the fuel pressurizing chamber 216 and remains closed. Can be. When the pump cam further rotates and the plunger descends, when the solenoid valve is not energized, the urging force of the urging means exceeds the pressure in the fuel pressurizing chamber 216, so that the valve body 223 is separated from the valve seat 221. Therefore, the fuel is supplied from the fuel passage 213 to the fuel pressurizing chamber 216. By this repetition, it is possible to increase the common rail internal pressure even in a state where the cylinder discrimination is not established. Then, the driving force of the starter motor is transmitted to the crankshaft to perform cranking rotation.

(3) Engine cylinder discrimination While the crankshaft is rotating, the valve camshaft on which the pump cam is mounted is interlocked with the crankshaft, so that the cylinder discrimination is established by input of a crank angle signal. After the cylinder discrimination is established, the high-pressure fuel supply pump 104 shifts to pump control during normal operation. In other words, the phase of the pump cam 111 is determined by the cylinder determination, whereby the control of the energization timing of the solenoid valve 220 as the metering valve, that is, the opening / closing timing control of the metering valve can be easily performed. After the cylinder discrimination is established, the injector 106 continues the injection two or more times during one cycle of intake, compression, combustion and exhaust, in this example. This is for cold start
By controlling the air-fuel ratio to the rich side, the ignition of the air-fuel mixture is accelerated, the first explosion is performed early, and the start mode is completed.

(4) Initial Explosion of Engine The rotation of the crankshaft by the starter motor eventually completes the initial explosion after the cylinder discrimination is established. After the first explosion, combustion is realized in other cylinders, and the engine speed increases early. Until the engine speed reaches a predetermined value, that is, until the start is completed, the injector continues to execute the injection multiple times.

(5) Completion of Engine Start When the engine speed reaches a predetermined value or more, the injector control is switched to ordinary single injection. One fuel injection period (fuel injection amount) is a period of a processing result calculated based on signals such as an engine load signal and an engine rotation signal. In the present embodiment, the completion of the engine start is detected by the predetermined rotation value of the engine speed, but in the present invention, the completion of the engine start may be detected by the predetermined value of the common rail internal pressure.

Next, a control method of the high-pressure pump control and the injector control in the engine start mode will be described. FIG. 7 illustrates high pressure pump control. First, the engine start state is read (step 201), the starter is turned on (step 202), and duty driving of the solenoid valve 220, which is a high-pressure fuel supply pump metering valve, is started (step 20).
3) It is determined whether the determination of the engine cylinder has been confirmed (step 204).

If the determination of the engine cylinder has not been confirmed, the crank angle signal is input (step 20).
7) If the crank angle signal is less than the predetermined number of times (step 206), the duty driving of the metering valve of the high-pressure fuel supply pump 104 is continued (step 203). If the crank angle signal has not been input (step 207), the starter is stopped (step 208). This is to switch off the starter when the crank angle sensor is out of order. After the cylinder discrimination of the engine has been confirmed (step 204), the basic drive timing of the metering valve of the high-pressure fuel supply pump 104 is calculated (step 205).
The control is switched to normal high-pressure pump timing control (step 209).

On the other hand, regarding the injector control, FIG.
As shown in (1), first, the engine operating state is read (step 301), the engine cylinder discrimination is read (step 302), and the common rail pressure is read (step 30).
3). If it is less than the common rail pressure P _c is a predetermined pressure P _SG (step 304), the engine coolant temperature T _EW is the set temperature T _EW
Is less than _G (step 305), instructs the multiple injection injector (step 306), as long as the engine speed N _E is lower than the predetermined engine speed N _ESG (step 309), a plurality of times injection of the injector continue.
At this time, the engine rotational speed N _E is predetermined engine speed N
_If it exceeds _SG (step 309), then the injector is switched to normal operation control (step 310).

If the common rail pressure _Pc is equal to or higher than the set pressure _PSG (step 304), it is determined that the common rail is high, and
A single injection start increase command of the injector is output (step 308). This is because the starting state is ended early and the normal operating state is started by increasing the starting amount at the time of starting. The engine speed N _E is the predetermined rotational speed N
_{If it is equal to} or higher than _ESG , the injector is switched to normal operation control (step 310).

Common rail pressure P_cIs the predetermined pressure P_SGLess than d
Engine water temperature T_EWIs the predetermined temperature T_EWGIs determined to be more than
(Step 305), the engine speed N_EIs prescribed
Revolution N_SGIf less than (Step 307), inject
A plurality of injection commands are output from the injector (step 306).
At this time, the engine speed N_EIs the predetermined rotation speed N_SGIs over
If it is determined that the first explosion has been completed,
A single injection start increase amount is commanded (step 308).
Unstable start control by instructing the injector to increase the single injection start
The state is shifted to the normal operation control early. D
Engine rotation speed N _EIs the predetermined rotation speed N_ESGOnce this is reached,
Switching to normal injector operation control (step 31)
0).

As described above, according to this embodiment,
Even in a state where the cylinder discrimination is not established, the pressure in the fuel pressurizing chamber can be increased, and the internal pressure of the common rail can be increased at an early stage. In addition, when the engine is started, the injector 106 performs the pulse injection a plurality of times per cycle, so that an air-fuel mixture that easily burns to an unstable state with a relatively low rotation speed is generated in the combustion chamber, and the combustion is performed. Promote and shorten the startup period. That is, the unstable operating state at the time of starting is completed early, and the comfort of the engine operating performance and the reduction of the exhaust gas emission are realized.

According to the present embodiment, when the engine is started, a plurality of injections by the injector 106 are executed from the initial stage of the start, and the low-pressure fuel supply pump pressure is started immediately after the start notice signal is input, thereby completing the engine start. There is an effect that the process is terminated early and the starter load is reduced. Therefore, there is an effect that the power source mounted on the vehicle can be saved, the fuel efficiency can be improved due to the early completion of the start, and the life of the starter can be prolonged.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a fuel supply device of the present invention.

FIG. 2 is a cross-sectional view of a high-pressure pressure regulator according to an embodiment of the present invention.

FIG. 3 is a sectional view of a main part when the solenoid valve of FIG. 2 is turned on.

FIG. 4 is a sectional view of a main part of the high-pressure pressure regulator shown in FIG. 2 when an electromagnetic valve is turned off.

FIG. 5 is a sectional view of a high-pressure fuel supply pump according to an embodiment of the present invention.

FIG. 6 is a time chart of engine start control according to the embodiment of the present invention.

FIG. 7 is a control flow of the high-pressure pump control according to the embodiment of the present invention.

FIG. 8 is a control flow of injector control according to the embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 10 high-pressure pressure regulator 11 housing 12 valve body 15 needle valve 21 fixed core 22 movable core 100 fuel tank 101 low-pressure fuel supply pump 102 filter 103 low-pressure pressure regulator 104 high-pressure fuel supply pump 105 common rail 106 injector 107 pressure sensor 110 ECU 112 electromagnetic pressure Regulator (high pressure type pressure regulator) 113 Mechanical pressure regulator (high pressure type pressure regulator)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location F02M 37/08 F02M 37/08 A 47/02 47/02 F02N 17/08 F02N 17/08 F

Claims (6)

[Claims] An accumulator fuel for an engine comprising: a high-pressure fuel supply pump capable of pressurizing fuel; a common rail having an accumulator for accumulating high-pressure fuel; and an injector for supplying fuel accumulated in the accumulator to the engine. In the supply device, during the period from the input of the engine start start signal to the input of the engine start completion signal, the fuel injection of the injector is performed a plurality of times per cycle. 2. The method according to claim 1, wherein a low-pressure fuel supply pump is driven when an engine start prediction signal is input prior to inputting the engine start start signal. . 3. The accumulator fuel supply device for an engine according to claim 1, wherein the engine start start signal is any one of a starter-on signal, a low-pressure fuel supply pump-on signal, and an ignition key-on signal. Control method. 4. The engine start completion signal is one of a common rail pressure predetermined value detection signal of a pressure sensor for detecting a pressure of a fuel supply system and an engine speed predetermined value signal. 5. A control method for an accumulator fuel supply device for an engine according to claim 4. 5. A high-pressure fuel supply pump for reciprocating a plunger by cam driving to pressurize fuel in a fuel pressurizing chamber and controlling a discharge amount by controlling opening / closing timing of a metering valve provided in the pressurizing chamber. A normal rail having an accumulator for storing high-pressure fuel pumped from the high-pressure fuel supply pump; and an injector for supplying fuel accumulated in the accumulator to the engine. A pressure accumulating fuel for an engine, comprising controlling opening / closing timing of the metering valve based on calculation of a cam phase, and performing duty control on opening / closing of the metering valve when the cam phase cannot be calculated at the time of starting. A control method of the supply device. 6. The pressure-accumulating fuel supply for an engine according to claim 5, wherein the fuel injection of the injector is performed a plurality of times per cycle during a period from an input of an engine start start signal to an input of an engine start completion signal. How to control the device.