JP5991192B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device for a hybrid vehicle equipped with an in-cylinder injection type engine.

  Conventionally, in a hybrid vehicle having a spark ignition type in-cylinder injection type engine that directly injects fuel into a cylinder and an electric motor that is driven by electric power from a battery as a drive source, after the engine is stopped, The pressure of the remaining high-pressure fuel decreases with the stop of the high-pressure pump, and the high-pressure fuel remaining in the delivery pipe is heated by the engine heat to become high temperature and low pressure, so fuel vapor is generated in the delivery pipe. The restartability of the engine sometimes deteriorated.

  In order to solve this problem, when the engine stops at a high temperature, the motor is rotated to drive the high-pressure pump to maintain the pressure of the fuel in the delivery pipe, so that the fuel remaining in the delivery pipe is heated by the engine. A technique is known in which generation of fuel vapor is suppressed even when heated by an engine so that the restartability of the engine can be improved (see, for example, Patent Document 1).

JP 2010-137596 A

  However, in a hybrid vehicle, when the start operation of the system is performed by an ignition switch, the temperature of the engine cooling water is lower than a predetermined temperature, or the remaining capacity of the battery is lower than a limit value, the warm vehicle is heated. Engine self-starting for machine operation and battery charging is performed, but if the engine cooling water temperature is higher than the specified temperature and the remaining battery capacity is higher than the limit value, engine self-starting is performed. Is not done.

  For this reason, in the conventional technique described in Patent Document 1, when an in-cylinder injection type engine that raises the fuel pressure of the fuel by the rotation of the engine is provided, the engine starts a load request in response to a request for driving force. Until the fuel pressure of the fuel is maintained at the holding fuel pressure, and the fuel does not always rise to the required fuel pressure to start the engine load demand, so normal driving is not possible and drivability deteriorates There was a problem of doing.

  The present invention has been made to solve such a problem, and provides a control device for a hybrid vehicle that can generate an engine output corresponding to a required driving force when a load request is started and can improve drivability. For the purpose.

  In order to solve the above problems, a control device for a hybrid vehicle according to the present invention includes (1) an internal combustion engine having an internal combustion engine body and a fuel supply device that supplies fuel to the internal combustion engine body, and electric power supplied from a battery. And the fuel supply device has a high-pressure side fuel supply mechanism that raises the fuel pressure of the fuel using the internal combustion engine body as a drive source and injects the fuel into the cylinder of the internal combustion engine body. A control device for a hybrid vehicle capable of traveling by at least one of a driving force generated by the internal combustion engine body and a driving force generated by the electric motor, wherein the hybrid vehicle can travel when the internal combustion engine is in a high temperature state. When an activation operation for bringing the engine into a state is performed, the internal combustion engine body is started in response to the activation operation, and intermittent stop of the internal combustion engine body is prohibited. It is constructed from.

  With this configuration, when a starting operation for bringing the hybrid vehicle into a travelable state is performed, the internal combustion engine body is started in response to the starting operation, whereby a high-pressure side fuel supply using the internal combustion engine body as a drive source is performed. Since the mechanism increases the fuel pressure of the fuel, the fuel vapor can be quickly eliminated, and the fuel can be boosted to the fuel pressure required when starting the internal combustion engine body in response to a request for driving force.

  Further, by prohibiting the internal combustion engine body from being intermittently stopped, it is possible to prevent the internal combustion engine body from being intermittently stopped and the increase in fuel pressure being interrupted. For this reason, the fuel pressure of the fuel can be raised and stabilized prior to the load request start for starting the internal combustion engine body in response to the drive force request. Therefore, engine output corresponding to the required driving force can be generated at the time of starting the load request, and drivability can be improved.

  In the hybrid vehicle control device described in (1) above, (2) the internal combustion engine body is started in response to the start-up operation, and the fuel pressure of the fuel supplied by the fuel supply device to the internal combustion engine body is It is preferable to prohibit intermittent stop of the internal combustion engine body until the fuel pressure is increased to a required fuel pressure required for starting the load request of the internal combustion engine body and is stabilized.

  With this configuration, since the internal combustion engine main body is prohibited from being intermittently stopped until the fuel pressure rises to the required fuel pressure and stabilizes, the fuel pressure can be quickly increased and stabilized to the required fuel pressure.

An apparatus as claimed in above SL (2), (3) when the shift selector is a parking range, while starting the internal combustion engine main body in response to the starting operation, the internal combustion engine is a high temperature state If it is, once the shift selector to lock so that it can not move from the parking range to another range, the fuel supply system is stabilized by boosting the fuel pressure the request fuel pressure of fuel supplied to the internal combustion engine body, It is preferable to unlock the shift selector.

  With this configuration, until the fuel pressure rises to the required fuel pressure and stabilizes, the shift selector is locked to the parking range, so the driver's ability before the fuel fuel pressure rises to the required fuel pressure and stabilizes is not sufficient. It is possible to prevent the hybrid vehicle from traveling in the state.

  In the hybrid vehicle control device according to any one of (1) to (3), (4) the fuel supply device increases the fuel pressure of the fuel by the electric power supplied from the battery, and the internal combustion engine body It is preferable to further have a low-pressure side fuel supply mechanism for injecting fuel into the intake port of the engine.

  This configuration improves the knocking effect by injecting the fuel into the cylinder of the internal combustion engine body and the volumetric efficiency of the intake air, and improves the homogeneity of the air-fuel mixture by injecting the fuel into the intake port of the internal combustion engine body. Can be achieved at the same time.

  According to the present invention, it is possible to provide a control device for a hybrid vehicle that can generate an engine output corresponding to a required driving force when a load request is started and can improve drivability.

It is the schematic which shows the hybrid vehicle carrying the control apparatus of the hybrid vehicle which concerns on embodiment of this invention. It is the schematic which shows the engine carrying the control apparatus of the hybrid vehicle which concerns on embodiment of this invention. It is the schematic which shows the intake device and engine main body which concern on embodiment of this invention. It is a flowchart which shows operation | movement of the control apparatus of the hybrid vehicle which concerns on embodiment of this invention. It is a timing chart which shows operation | movement of the control apparatus of the hybrid vehicle which concerns on embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the present embodiment, the hybrid vehicle to which the present invention is applied is a hybrid vehicle employing a dual injection type internal combustion engine that uses both in-cylinder injection and port injection, for example, an in-line four-cylinder gasoline engine.

  First, the configuration will be described.

  As shown in FIG. 1, hybrid vehicle 100 includes an engine 1 as an internal combustion engine, motors MG1 and MG2 as electric motors, power split mechanism 101, reduction mechanism 107, differential gear 102, and drive wheels 103. Inverter 104, battery 105, and control unit 106 are provided.

  The hybrid vehicle 100 is a series / parallel type hybrid vehicle that can run using at least one of the engine 1 and the motor MG2 as a drive source and starts the engine 1 by the motor MG1. .

  Engine 1, motor MG <b> 1, and motor MG <b> 2 are connected to each other via power split mechanism 101. A reduction mechanism 107 is connected to the rotation shaft 108 of the motor MG2 coupled to the power split mechanism 101.

  The rotating shaft 108 of the motor MG2 is connected to the drive wheel 103 via the reduction mechanism 107 and the differential gear 102, and is connected to the crankshaft 14 of the engine 1 via the power split mechanism 101.

  The power split mechanism 101 can split the driving force of the engine 1 into the motor MG1 and the reduction mechanism 107. The distribution of the driving force by the power split mechanism 101 can be arbitrarily changed. The motor MG1 can function as a starter that starts the engine 1 by rotating the crankshaft 14 of the engine 1 via the power split mechanism 101.

  The power split mechanism 101 includes a planetary gear mechanism, and includes a sun gear 110, a ring gear 111, a plurality of planetary pinion gears 112, and a planetary carrier 113. The sun gear 110 is connected to a hollow sun gear shaft 115 penetrating the center of a carrier shaft 114 coaxial with the crankshaft 14.

  The ring gear 111 is connected to the rotating shaft 108 of the motor MG2 which is a ring gear shaft coaxial with the carrier shaft 114. The planetary pinion gear 112 is disposed between the sun gear 110 and the ring gear 111, and revolves while rotating on the outer periphery of the sun gear 110.

  The planetary carrier 113 is connected to the carrier shaft 114 and pivotally supports the rotation shaft of each planetary pinion gear 112.

  In power split device 101, three shafts of sun gear 110, ring gear 111 and planetary carrier 113, sun gear shaft 115, rotation shaft 108 of motor MG2 and carrier shaft 114 are used as power input / output shafts. When the power input / output to / from the two axes is determined, the power input / output to the remaining one axis is determined based on the determined power input / output to the two axes.

  The reduction mechanism 107 includes a power take-out gear 120, a chain belt 121, and a power transmission gear train 122. The power take-out gear 120 is connected to a power transmission gear train 122 via a chain belt 121.

  The power take-out gear 120 is coupled to the ring gear 111 of the power split mechanism 101 and transmits power received from the ring gear 111 to the power transmission gear train 122 via the chain belt 121. The power transmission gear train 122 is configured to transmit power to the drive wheels 103 via the differential gear 102.

  Each of the motor MG1 and the motor MG2 includes a known synchronous generator motor that can be driven as a generator and can be driven as a motor. Motor MG1 and motor MG2 are connected to inverter 104, respectively. Each inverter 104 is connected to a battery 105.

  The battery 105 charges and discharges the motors MG1 and MG2. The motor MG1 includes an output shaft 109 as an output shaft of the electric motor.

  The control unit 106 includes a hybrid electronic control unit (hereinafter referred to as ECU) 140, an engine electronic control unit (hereinafter referred to as engine ECU) 141, and a motor electronic control unit (hereinafter referred to as motor ECU). 142 and a battery electronic control unit (hereinafter referred to as a battery ECU) 143. ECU 140 in the present embodiment constitutes a hybrid vehicle control device in the present invention.

  ECU 140 is connected to engine ECU 141, motor ECU 142, and battery ECU 143 via a communication port (not shown). The ECU 140 exchanges various control signals and data with the engine ECU 141, the motor ECU 142, and the battery ECU 143.

  Engine ECU 141 is connected to engine 1 and ECU 140. The engine ECU 141 receives signals from various sensors that detect the operating state of the engine 1 and performs operation control such as fuel injection control, ignition control, and intake air amount adjustment control in accordance with the input signals. .

  Motor ECU 142 is connected to inverter 104 and ECU 140. The motor ECU 142 drives and controls the motor MG1 and the motor MG2.

  Battery ECU 143 is connected to battery 105 and ECU 140. The battery ECU 143 calculates a remaining capacity (hereinafter referred to as SOC (State of Charge)) based on the integrated value of the charge / discharge current of the battery 105.

  The hybrid vehicle includes a shift selector 954, and the control unit 106 includes a shift lock control unit (hereinafter referred to as shift lock ECU) 952.

  The shift selector 954 is for selecting the travel range of the hybrid vehicle 100, and is selected from the P (parking) range, N (neutral) range, D (drive) range, and R (reverse) range by the driver. An operation lever 955 operated to the position is provided.

  The shift selector 954 outputs a signal corresponding to the position of the operation lever 955 to the ECU 140.

  The shift lock ECU 952 is configured to lock or unlock the operation lever 955 of the shift selector 954 in accordance with a control signal from the ECU 140.

  Specifically, the shift selector 954 includes a lock mechanism (not shown) that mechanically locks the operation lever 955 disposed in the P range so that it cannot be moved to another range such as the D range or the N range. .

  The shift lock ECU 952 locks the lock mechanism of the shift selector 954 when a control signal for prohibiting the operation of the operation lever 955 from the P range to another range is input from the ECU 140.

  In this state, the operation lever 955 of the shift selector 954 is locked to the P range, and the operation lever 955 cannot be moved to the D range, so that the driver cannot travel the hybrid vehicle 100.

  Further, the shift lock ECU 952 unlocks the lock mechanism of the shift selector 954 when a control signal permitting operation of the operation lever 955 from the P range to another range is input from the ECU 140.

  In this state, since the operation lever 955 can move from the P range to the D range, the driver can travel the hybrid vehicle 100.

  As shown in FIGS. 2 and 3, the engine 1 includes an engine body 2 as an internal combustion engine body, an intake device 3, an exhaust device 4, a fuel supply device 5, and a cooling device 6.

  The engine body 2 includes a cylinder block 10 and a cylinder head 20. The cylinder block 10 and the cylinder head 20 include cylinders 11 as four cylinders. The cylinder 11 is provided with the vertical direction as the longitudinal direction.

  The cylinder block 10 includes a piston 12, a connecting rod 13, a crankshaft 14 as an output shaft of the internal combustion engine body, and a crank angle sensor 15. The piston 12 is provided so as to reciprocate within the cylinder 11.

  The piston 12 is rotatably connected to the connecting rod 13. The connecting rod 13 is rotatably connected to the crankshaft 14. The crank angle sensor 15 detects the rotational speed of the crankshaft 14 and inputs it to the ECU 140.

  In the engine body 2, a combustion chamber 16 is formed by the cylinder block 10, the cylinder head 20, and the piston 12. The engine body 2 is configured to reciprocate the piston 12 by burning a mixture of fuel and air in the combustion chamber 16 at a desired timing, and to rotate the crankshaft 14 via the connecting rod 13.

  The cylinder head 20 includes an intake port 21, an intake valve 22, an intake camshaft (not shown), an exhaust port 23, an exhaust valve 24, an exhaust camshaft (not shown), and an ignition plug 25.

  The intake port 21 communicates the intake passage of the intake device 3 and the combustion chamber 16. The intake valve 22 opens and closes between the intake port 21 and the combustion chamber 16 by moving up and down, and controls the introduction of the intake air A from the intake passage of the intake device 3 to the combustion chamber 16. The intake camshaft is configured to raise and lower the intake valve 22.

  The exhaust port 23 communicates the combustion chamber 16 and the exhaust passage of the exhaust device 4. The exhaust valve 24 opens and closes the combustion chamber 16 and the exhaust port 23 by raising and lowering, and controls the discharge of the exhaust gas G from the combustion chamber 16 to the exhaust passage of the exhaust device 4. The exhaust camshaft moves the exhaust valve 24 up and down.

  The intake valve 22 communicates the combustion chamber 16 with the intake passage when the valve is opened, and the exhaust valve 24 communicates the combustion chamber 16 with the exhaust passage when the valve is opened. When the piston 12 descends with the combustion chamber 16 communicating with the intake passage by opening the intake valve 22, the combustion chamber 16 can suck the intake air A through the intake passage.

  Further, when the piston 12 rises in a state where the combustion chamber 16 communicates with the exhaust passage by opening the exhaust valve 24, the combustion chamber 16 can exhaust the exhaust gas G through the exhaust passage.

  The spark plug 25 is provided in the combustion chamber 16 so as to be capable of spark ignition. The ignition plug 25 is configured so that the ignition timing is controlled by the ECU 140.

  The intake device 3 includes an intake port pipe 30, an air cleaner 31, an intake pipe 32, an aero flow meter 33, an intake temperature sensor 956, a throttle valve 34, a surge tank 35, and an intake manifold 36. . The air cleaner 31 is cleaned by removing dust and the like from the intake air A by a built-in filter at an upstream portion of the intake device 3.

  The aero flow meter 33 detects the intake flow rate of the intake air A. The intake air temperature sensor 956 detects the temperature of the intake air A (hereinafter referred to as intake air temperature). The aero flow meter 33 and the intake air temperature sensor 956 are provided between the air cleaner 31 and the throttle valve.

  The throttle valve 34 is provided between the air cleaner 31 and the surge tank 35 and adjusts the intake flow rate of the intake air A supplied to each cylinder 11 by electronic control. The intake manifold 36 connects the intake pipe 32 and each cylinder 11.

  The intake air A is distributed from the intake pipe 30 in the order of air cleaner 31 → throttle valve 34 → surge tank 35 → intake manifold 36 and flows into each cylinder 11. Further, the engine body 2 and the intake device 3 are connected by the connection between the intake manifold 36 and each cylinder 11.

  The exhaust device 4 includes an exhaust manifold 40, an exhaust gas pipe 41, and an exhaust after-treatment device (not shown).

  The exhaust manifold 40 circulates the exhaust gas G discharged from each cylinder 11. By connecting the exhaust manifold 40 and each cylinder 11, the engine body 2 and the exhaust device 4 are connected. The exhaust gas pipe 41 connects the exhaust manifold 40 and the exhaust aftertreatment device.

  The fuel supply device 5 includes a low-pressure side fuel supply mechanism 50 and a high-pressure side fuel supply mechanism 80. The fuel supply device 5 injects fuel into the intake port 21 and the combustion chamber 16 of the engine body 2. That is, the engine 1 includes a dual injection type fuel supply device 5 that uses both in-cylinder injection and port injection.

  The low-pressure side fuel supply mechanism 50 and the high-pressure side fuel supply mechanism 80 pressurize the fuel and inject it into the intake port 21 and the combustion chamber 16 of the engine body 2, respectively.

  For this reason, the engine 1 includes a dual injection type fuel supply device 5 that uses both in-cylinder injection and port injection, and thereby the knocking improvement effect by injecting the fuel into the combustion chamber 16 of the engine body 2. In addition, the volumetric efficiency of the intake air and the homogeneity of the air-fuel mixture by injecting fuel into the intake port 21 of the engine body 2 can be achieved at the same time.

  The low-pressure side fuel supply mechanism 50 is for injecting fuel into the intake port 21 of the engine body 2, and includes a fuel pressure sending part 51, a low-pressure side fuel pipe 52, a low-pressure side delivery pipe 53, and a low-pressure side injector. 54.

  The fuel pressure feeding unit 51 includes a fuel tank 511, a feed pump unit 512, a suction filter 513, a fuel filter 514, a fuel pressure control valve 515, and a fuel pipe 516 connecting them.

  The fuel tank 511 stores fuel consumed by the engine body 2, for example, gasoline. The feed pump unit 512 incorporates a feed pump (not shown), and is driven and stopped based on an on / off command signal transmitted from the ECU 140.

The feed pump unit 512 can pump up fuel from the fuel tank 511 using a motor (not shown) as a drive source, and pressurize the pumped fuel to a pressure within a constant variable range of, for example, less than 1 [MPa] and discharge the fuel. ing. Furthermore, the feed pump unit 512 can change the discharge amount [m ³ / sec] per unit time and the discharge pressure [MPa] under the control of the ECU 140.

  That is, the feed pump unit 512 can be variably controlled in the discharge amount and discharge pressure per unit time by the on / off drive and the rotation speed control by the ECU 140.

  The feed pump unit 512 is a variable fuel pump or a variable fuel pressure pump capable of increasing at least one of the fuel supply flow rate and the supply pressure through the supply pipes of the low pressure side fuel supply mechanism 50 and the high pressure side fuel supply mechanism 80. It has become.

  The suction filter 513 is provided at the suction port of the feed pump unit 512, and prevents suction of foreign matter. The fuel filter 514 is provided at the discharge port of the feed pump unit 512 and removes foreign matters in the discharged fuel.

  The fuel pressure control valve 515 includes a diaphragm (not shown) that receives the pressure of the fuel discharged from the feed pump unit 512 in the valve opening direction, and a compression coil spring (not shown) that urges the diaphragm in the valve closing direction.

  The fuel pressure control valve 515 opens when the pressure of the fuel received by the diaphragm exceeds the set pressure, and maintains the closed state while the pressure of the fuel received by the diaphragm does not reach the set pressure. Thereby, the fuel pressure control valve 515 adjusts the pressure of the fuel discharged into the low pressure side fuel pipe 52 to a preset low pressure side supply pressure, for example, 400 [kPa].

  The low-pressure fuel pipe 52 is a pipe that connects the fuel pump 51 to the low-pressure delivery pipe 53. However, the low-pressure side fuel pipe 52 is an arbitrary member that forms a fuel passage, and is not limited to a fuel pipe. One member through which the fuel passage is formed or a fuel passage between the members is formed. A plurality of members may be formed.

  The low-pressure delivery pipe 53 is connected to the low-pressure fuel pipe 52 at one end of the cylinder 11 in the series arrangement direction. A low-pressure injector 54 is connected to the low-pressure delivery pipe 53 at the same interval as the cylinder 11 in the series arrangement direction of the cylinders 11.

  The low-pressure delivery pipe 53 distributes the fuel from the fuel pumping unit 51 to each low-pressure injector 54 at an equivalent pressure. The low pressure delivery pipe 53 is equipped with a low pressure fuel pressure sensor 53a that detects the internal fuel pressure.

  The low pressure side injector 54 is provided as a port injection injector with the injection hole portion 54 a exposed in the intake port 21 corresponding to each cylinder 11. The low pressure side injector 54 is opened by an electromagnetic valve portion (not shown) driven by an injection command signal from the ECU 140 and a valve opening operation to inject fuel into the intake port 21 from the injection hole portion 54a when the electromagnetic valve portion is energized. It consists of a fuel injection valve provided with a nozzle part that does not.

  When any one of the plurality of low-pressure injectors 54 opens, the pressurized fuel in the low-pressure delivery pipe 53 is injected into the intake port 21 from the injection hole portion 54a of the low-pressure injector 54. It has become.

  The high-pressure side fuel supply mechanism 80 is for injecting fuel into the combustion chamber 16 of the engine body 2, and includes a high-pressure pump portion 81 as a high-pressure pump, a high-pressure side fuel pipe 82 as a pipe, and a high-pressure side delivery. A pipe 83 and a high-pressure injector 84 as an injector are provided.

  The high-pressure pump unit 81 includes an upstream pipe 90, a downstream pipe 91, a pulsation damper 92, a high-pressure pump main body 93, and an electromagnetic spill valve 94. The high pressure pump unit 81 is attached to the upper side of the cylinder head 20 and is connected between the low pressure side fuel pipe 52 and the high pressure side fuel pipe 82. The upstream side pipe 90 is connected to the branch pipe 52 a of the low pressure side fuel pipe 52. The downstream pipe 91 is connected to the high-pressure fuel pipe 82.

  The pulsation damper 92 is provided in the upstream pipe 90, and has an elastic diaphragm (not shown) that receives the fuel pressure, and a compression coil spring (not shown). The pulsation damper 92 changes the internal volume by elastic deformation of the diaphragm, and suppresses pressure pulsation of fuel in the upstream side pipe 90.

  The high-pressure pump main body 93 includes a pump housing 931, a plunger 932, a camshaft 933, a follower lifter 934, and a return spring 935.

  The pump housing 931 includes a columnar pressurizing chamber 931a formed inside. The plunger 932 has a cylindrical shape and is slidably provided in the pump housing 931. The plunger 932 is configured to change the volume of the pressurizing chamber 931a by sliding. The camshaft 933 is provided at one end of the exhaust camshaft of the engine body 2 and has a cam 933a at the end.

  The follower lifter 934 is integrated with the plunger 932, and the plunger 932 is slid by being pressed by the cam 933a. The return spring 935 is composed of a compression coil spring provided between the pump housing 931 and the follower lifter 934, and biases the follower lifter 934 toward the cam 933a.

  For this reason, since the camshaft 933 is always rotating while the engine 1 is being driven, the high-pressure pump main body 93 is always operated. Even when the engine 1 is stopped, the high-pressure pump main body 93 operates when the engine main body 2 is pushed by the MG 1.

  In the high-pressure pump main body 93, the pressurizing chamber 931a changes the volume by the reciprocating movement of the plunger 932, thereby performing the suction, pressurization, and discharge operations of the fuel from the feed pump unit 512.

  The high-pressure pump main body 93 pressurizes the fuel introduced into the pressurizing chamber 931a from the low-pressure side fuel pipe 52 from, for example, about 400 [kPa] to, for example, about 4 [MPa] to 13 [MPa], and thereby high-pressure side fuel. It discharges to the piping 82.

  The electromagnetic spill valve 94 includes a valve body 941, an electromagnetic drive coil 942, and a pressing spring 943.

  The valve body 941 is slidably provided with respect to the pump housing 931 and can open and close between the upstream pipe 90 and the pressurizing chamber 931a. The electromagnetic drive coil 942 is energized by the ECU 140 to electromagnetically drive the valve body 941. The pressing spring 943 is formed of a compression coil spring and urges the valve body 941 in the valve opening direction at all times.

  The valve body 941 opens so as to introduce the fuel fed from the feed pump unit 512 into the pressurizing chamber 931a when the electromagnetic drive coil 942 is in a non-excited state. Further, the valve body 941 is configured to perform a valve closing operation so as to enable pressurization and discharge operations of the high-pressure pump main body 93 at the time of driving in which the electromagnetic drive coil 942 is excited.

  When the electromagnetic spill valve 94 is closed in response to an input signal from the ECU 140, the electromagnetic spill valve 94 has a check valve function for preventing high-pressure backflow. Further, when the electromagnetic spill valve 94 is opened in response to an input signal from the ECU 140, the intake of fuel into the pressurizing chamber 931 a or the low pressure side fuel piping 52 of the fuel in the pressurizing chamber 931 a according to the displacement of the plunger 932. It is designed to allow leakage into

  The electromagnetic spill valve 94 closes the pressurizing chamber 931a by the valve body 941 when the electromagnetic drive coil 942 is excited. The electromagnetic spill valve 94 sucks fuel into the pressurizing chamber 931a, pressurizes the fuel in the pressurizing chamber 931a, and pressurizes by the volume change of the pressurizing chamber 931a due to the reciprocating movement of the plunger 932. The fuel is discharged from the chamber 931a.

  The high-pressure side fuel pipe 82 is composed of a pipe connecting the high-pressure pump unit 81 to the high-pressure side delivery pipe 83, and is provided with a check valve 82a on the way. The high-pressure side fuel pipe 82 is an arbitrary member that forms a fuel passage, and is not limited to a fuel pipe. One member through which the fuel passage is formed or a fuel passage is formed between them. A plurality of members may be used.

  The check valve 82 a is provided in the vicinity of the high-pressure pump unit 81. The check valve 82a opens when the fuel pressure on the high-pressure pump unit 81 side becomes larger than the fuel pressure on the high-pressure injector 84 side with a significant differential pressure of about 100 [kPa], for example. When the pressure on the side is substantially equal to or smaller than the pressure on the high-pressure side injector 84 side, the valve is closed.

  The high-pressure delivery pipe 83 is connected to the high-pressure fuel pipe 82 on one end side in the series arrangement direction of the cylinders 11. A high pressure side injector 84 is connected to the high pressure side delivery pipe 83 at the same interval as the cylinder 11 in the series arrangement direction of the cylinders 11.

  As a result, the high-pressure delivery pipe 83 distributes the fuel from the high-pressure pump unit 81 to each high-pressure injector 84 at an equivalent pressure. The high-pressure delivery pipe 83 is equipped with a high-pressure fuel pressure sensor 83a that detects the internal fuel pressure.

  The high pressure side injector 84 is provided as an in-cylinder injector with the injection hole portion 84a exposed in the combustion chamber 16 of each cylinder 11. The high pressure side injector 84 is opened by an electromagnetic valve portion (not shown) driven by an injection command signal from the ECU 140 and a valve opening operation to inject fuel into the combustion chamber 16 from the injection hole portion 84a when energizing the electromagnetic valve portion. It consists of a fuel injection valve provided with a nozzle part that does not.

  When any one of the plurality of high pressure side injectors 84 opens, the pressurized fuel in the high pressure side delivery pipe 83 is injected into the combustion chamber 16 from the injection hole portion 84a of the high pressure side injector 84. It has become.

  The cooling device 6 includes a water jacket 61, a water pump (not shown), and a radiator (not shown). The cooling water W is circulated in the order of the water pump → the water jacket 61 → the radiator → the water pump.

  The water jacket 61 includes a cylinder block water jacket 61a formed on the cylinder block 10, a cylinder head water jacket 61b formed on the cylinder head 20, and a cooling water temperature sensor 61c.

  The cylinder block water jacket 61 a and the cylinder head water jacket 61 b are connected to each other and provided around each cylinder 11. The water jacket 61 cools the engine body 2 by circulating the cooling water W therein.

  The ECU 140 includes a CPU (Central Processing Unit) 140a, a ROM (Read Only Memory) 140b that stores fixed data, a RAM (Random Access Memory) 140c that temporarily stores data, and a rewritable nonvolatile memory. A backup memory (not shown) composed of a volatile memory, an input interface circuit (not shown) having an A / D converter and a buffer, and an output interface circuit (not shown) having a drive circuit and the like.

  The ECU 140 includes an aero flow meter 33, an ignition switch 950 that activates the system of the hybrid vehicle 100, a crank angle sensor 15, a low-pressure fuel pressure sensor 53a, a high-pressure fuel pressure sensor 83a, and a coolant temperature. The sensor 61c is connected.

  The ECU 140 also includes an accelerator sensor 72 that detects the accelerator opening from the depression angle of the accelerator pedal 71, a vehicle speed sensor 73 that detects the speed of the hybrid vehicle 100, an intake air temperature sensor 956 that detects the intake air temperature, and a hybrid vehicle. A travelable indicator 960 is connected to notify that 100 is in a travelable state by lighting.

  The ECU 140 performs a startup check to determine whether or not the system of the hybrid vehicle 100 is normal when the driver performs a startup operation of the system.

  Specifically, the ECU 140 receives the on / off signal from the ignition switch 950, the shift selector 954 is in the P range, and the signal from the ignition switch 950 is turned off when the foot brake (not shown) is operated. When it is turned on, a startup check is performed.

  In this activation check, it is determined whether there is no abnormality in the system and the traveling condition of the hybrid vehicle 100 is satisfied.

  The ECU 140 is lit on the runnable indicator 960 on the condition that the result of the start check is normal, and informs the driver that the hybrid vehicle 100 is in a runnable state. The travelable indicator 960 is configured as a lamp labeled “READY”, for example.

  Further, the ECU 140 is configured to set a driving force required by the driver based on the accelerator opening of the accelerator pedal 71 detected by the accelerator sensor 72.

  The ECU 140 follows the control program stored in the ROM 140b in advance, the accelerator opening detected by the accelerator sensor 72, the intake air amount detected by the aero flow meter 33, and the engine detected by the crank angle sensor 15. The basic injection amount required for each combustion is calculated based on the rotational speed and the like.

  Further, the ECU 140 refers to the set value information stored in the backup memory in advance based on the intake air temperature detected by the intake air temperature sensor 956, and sets the operating state of the engine 1 with respect to the basic injection amount. The fuel injection amount is calculated by performing various corrections and air-fuel ratio feedback corrections.

  Further, the ECU 140 outputs an injection command signal to the low-pressure injector 54 and the high-pressure injector 84, a valve drive instruction signal for driving the electromagnetic spill valve 94, etc. in a timely manner based on the calculated fuel injection amount. It has become.

  The ECU 140 adjusts the amount of fuel leakage from the pressurizing chamber 931a by the electromagnetic spill valve 94 to the low-pressure side fuel pipe 52. The ECU 140 can control the pressure of the fuel supplied from the high-pressure pump main body 93 to the high-pressure delivery pipe 83 to an optimum fuel pressure according to the operating state of the engine 1 and the injection characteristics of the high-pressure injector 84 by at least this adjustment. It has become.

  For example, the ECU 140 can set an on time during which the electromagnetic drive coil 942 of the electromagnetic spill valve 94 is in an excited state and an off time during which the excited state is released within a certain signal period.

  The ECU 140 adjusts the amount of fuel leaked from the pressurizing chamber 931a by the electromagnetic spill valve 94 by changing the ratio of on-time (0% to 100%; hereinafter referred to as duty ratio) within the signal period. be able to.

  Further, the ECU 140 is based on in-cylinder injection from the high-pressure side injector 84, for example, but the air-fuel mixture formation is insufficient only with in-cylinder injection such as when the engine 1 is warmed up or under a low rotation and high load. Under specific operating conditions, port injection from the low-pressure injector 54 is used together.

  Further, the ECU 140 stops energization of the electromagnetic drive coil 942 of the electromagnetic spill valve 94 and pressurizes the high-pressure pump unit 81 when the accelerator pedal 71 is turned off, for example, while the hybrid vehicle 100 is traveling at high speed. The fuel cut is impossible.

  In the present embodiment, when the hybrid vehicle 100 is stopped and the engine body 2 is in a high temperature state, the ECU 140 performs a system start-up operation by turning on the ignition switch 950. The engine body 2 is started and intermittent stop is prohibited.

  Specifically, the ECU 140 determines whether or not the engine 1 is in a high temperature state when it is determined that the system activation operation is performed and the result of the system activation check is normal. The ECU 140 determines whether or not the temperature of the cooling water detected by the cooling water temperature sensor 61c is equal to or higher than a predetermined value, or the intake air temperature detected by the intake air temperature sensor 956 is equal to or higher than a predetermined value. Or by referring to the history of the previous driving of the hybrid vehicle 100, whether or not the engine 1 is in an operating state where the temperature becomes high is determined.

  A fuel temperature sensor that detects the temperature of the fuel may be provided in the hybrid vehicle 100, and the ECU 140 may determine whether or not the engine 1 is in a high temperature state based on a detection signal of the fuel temperature sensor.

  If the ECU 140 determines that the engine 1 is in a high temperature state, the ECU 140 starts the engine body 2 and prohibits the engine body 2 from being intermittently stopped. Further, the operation lever 955 cannot move from the P range to another range. The shift selector 954 is locked.

  Here, as a mode of starting the engine 2 body, a load request start in which the engine body 2 is started in response to a request for driving force, and a self-supporting in which the engine body 2 is started in response to a request other than a request for driving force. There is a start.

  The start of the engine body 2 by the load request start is, for example, when the driving force required for the hybrid vehicle 100 is insufficient due to the output of the motor MG2 (that is, the output of the engine body 2 is necessary to satisfy the requested driving force) In the case where the engine body 2 is started, and the engine body 2 is started with the throttle valve 34 having a large opening.

  For example, the ECU 140 starts the engine body 2 by a load request start when the depression amount of the accelerator pedal 71 is a predetermined value or more, or when the change amount of the depression amount of the accelerator pedal 71 is a predetermined value or more. It has become.

  On the other hand, the independent start is a case where the engine body 2 is started to warm up the engine 1 or charge the battery 105. In this self-starting, the engine body 2 is started with the throttle valve 34 having a small opening.

  As described above, when the hybrid vehicle 100 is stopped and the engine main body 2 is in a high temperature state, the ECU 140 starts the engine main body 2 by a self-sustained start and performs an engine start operation. The intermittent stop of the main body 2 is prohibited, and the shift selector 954 is locked through the shift lock ECU 952 so that the operation lever 955 cannot move from the P range to another range.

  Further, the ECU 140 determines that the high-pressure side fuel pressure, that is, the fuel pressure in the high-pressure side delivery pipe 83 detected by the high-pressure side fuel pressure sensor 83a rises to the required fuel pressure for the load demand start of the engine body 2 and becomes stable. The shift selector 954 is unlocked in the P range, the runnable indicator is lit, and intermittent stop of the engine body 2 is permitted.

  Next, the operation of ECU 140 of hybrid vehicle 100 configured as described above will be described with reference to the flowchart of FIG. 4 and the timing chart of FIG.

  4 is a control program for the hybrid vehicle 100 that is executed by the CPU 140a of the ECU 140 using the RAM 140c as a work area. The control program for the hybrid vehicle 100 is stored in the ROM 140b of the ECU 140.

  In the control apparatus for hybrid vehicle 100 of the present embodiment configured as described above, the control process for hybrid vehicle 100 is executed at predetermined time intervals (for example, 10 ms) by ECU 140. ing.

  Here, in hybrid vehicle 100, the system is in an off state, the fuel pressure in high-pressure delivery pipe 83 is maintained at a predetermined holding pressure, and the SOC of battery 105 is greater than the limit value.

  First, ECU 140 determines whether or not a system activation operation of hybrid vehicle 100 has been performed (step S11). Whether or not the system activation operation has been performed is determined by whether or not the driver has operated the ignition switch 950 to the ON position.

  Then, if the determination in step S11 is NO (ignition switch 950 is off), ECU 140 returns the process to the main routine, and if the determination in step S11 is YES (ignition switch 950 is on), the ECU 140 checks the system startup. It performs (step S12). In the system activation check, the ECU 140 confirms whether or not the traveling condition for the hybrid vehicle 100 to travel is in a normal state based on signals from various sensors.

  Next, the ECU 140 determines whether or not the result of the activation check is normal (step S13). If the determination in step S13 is NO (abnormal), the process returns to the main routine.

  Next, when the determination in step S13 is YES (normal), the ECU 140 determines whether or not the engine 1 is in a high temperature state (step S14).

  Whether or not the engine 1 is in a high temperature state is whether the temperature of the cooling water detected by the cooling water temperature sensor 61c is a predetermined value or more, or the intake air temperature detected by the intake air temperature sensor 956 is a predetermined value or more. Alternatively, the determination is made based on at least one of whether or not the engine 1 is in an operating state in which the temperature of the engine 1 becomes high with reference to the previous driving history of the hybrid vehicle 100.

  If the determination in step S14 is NO (not in a high temperature state), the ECU 140 proceeds to step S19. If the determination in step S14 is YES (in a high temperature state), the ECU 140 starts the engine body 2 by a self-sustained start. The intermittent stop of the engine body 2 is prohibited (step S15), and the shift selector 954 is locked so that the operation lever 955 cannot move from the P range to another range (step S16).

  If the determination in step S14 is NO (not in a high temperature state), the ECU 140 detects the temperature of the cooling water, the SOC of the battery 105, and the like, and starts the engine body 2 by self-starting as necessary. Control goes to step S19.

  Steps S11 to S15 are executed at time T0 in FIG. That is, the ECU 140 starts the engine main body 2 by a self-sustained start when the driver performs the system start operation by the ignition switch 950 and the result of the system start check is normal and the engine 1 is in a high temperature state. Disable intermittent stop.

  5, when the engine body 2 is started at time T0, the high-pressure pump body 93 of the high-pressure side fuel supply mechanism 80 is driven by the engine body 2, so that the high-pressure side fuel pressure starts to rise.

  Further, at time T1, the rotation of the engine reaches the idle rotation speed, and at time T2, the high-pressure side fuel pressure reaches the required fuel pressure for starting the load request of the engine body 2.

  Next, the ECU 140 determines whether or not the fuel pressure of the fuel has risen and stabilized (step S17). Specifically, the ECU 140 determines whether or not the high-pressure side fuel pressure has risen to the required fuel pressure for the load request start of the engine body 2 and has stabilized.

  In step S17, as shown in FIG. 5, it is determined that the high-pressure side fuel pressure has risen to the required fuel pressure and is stable at time T3, which is 2 seconds after the high-pressure side fuel pressure has reached the required fuel pressure at time T2. . At time T, the following steps S18 to S20 are performed.

  ECU 140 continues the operation of prohibiting intermittent stop of engine body 2 and locking the P range of shift selector 954 until the determination in step S17 becomes YES (fuel pressure increase and stability).

  Next, when the determination in step S17 is YES (fuel pressure increase and stability), the ECU 140 unlocks the shift selector 954 in the P range (step S18), and lights the runnable indicator (step S19). The intermittent stop of the engine body 2 is permitted (step S20), and the flowchart of FIG.

  In step S18, since the lock of the shift selector 954 in the P range is released, the driver can move the operation lever 955 of the shift selector 954 from the P range to another range.

  In step S19, since the runnable indicator is turned on, the driver is informed that the hybrid vehicle 100 can run.

  In step S20, since the engine body 2 is allowed to be intermittently stopped, the engine ECU 141 intermittently stops the engine body 2 as necessary.

  As described above, when the engine 1 is in a high temperature state when the system activation operation is performed by the driver, the ECU 140 starts the engine body 2 by self-starting and prohibits intermittent stop, thereby preventing the engine body. When the fuel pressure in the high-pressure delivery pipe 83 is increased by the rotation of 2 and the fuel pressure in the high-pressure delivery pipe 83 rises to the required fuel pressure and is stabilized, the shift selector 954 is unlocked in the P range and is The operation lever 955 can be operated.

  For this reason, when the engine main body 2 starts a load request by the driver's accelerator operation while the hybrid vehicle 100 is traveling, the engine main body 2 can generate an engine output corresponding to the required driving force.

  FIG. 5 illustrates a case where the high-pressure side fuel pressure reaches the required fuel pressure at time T2 after the engine rotation reaches the idle rotation speed at time T1, but conversely, the engine rotation It is possible that the high-pressure side fuel pressure reaches the required fuel pressure before the engine reaches the idle speed.

  4 and 5, the ECU 140 determines in step S17 that the high-pressure side fuel pressure has increased to the required fuel pressure and is stable after 2 seconds since the high-pressure side fuel pressure has reached the required fuel pressure. The time until it is determined that the high-pressure side fuel pressure has stabilized after reaching the required fuel pressure is not limited to 2 seconds. The fuel boosting capability of the high-pressure pump body 93, the fuel boosting characteristic of the high-pressure side fuel supply mechanism 80, etc. It can be set according to.

  In FIG. 4, the shift selector 954 is unlocked in the P range in step S18, the runnable indicator is lit in step S19, and the engine body 2 is allowed to be intermittently stopped in step S20. Since these processes are performed at substantially the same timing, the order of the processes in steps S18 to S20 by the ECU 140 may be changed.

  In hybrid vehicle 100 described above, the operation when ECU 140 executes the flowchart of FIG. 4 will be described along the time chart shown in FIG.

  As shown in FIG. 5, before the time T0, the ignition switch 950 is in the OFF position, the system activation operation is not performed, the rotation speed of the engine body 2 is 0, and the high-pressure side fuel pressure, that is, the high-pressure side delivery The fuel pressure of the pipe 83 is kept at the holding pressure. Further, before T0, intermittent stop of the engine body 2 is permitted, and the shift selector 954 is unlocked.

  At time T0, the ignition switch 950 is turned on by the driver, the start-up check is performed by the ECU 140, and when the result is determined to be normal, the engine body 2 is started.

  When the engine body 2 is started at time T0, the high-pressure pump body 93 of the high-pressure side fuel supply mechanism 80 is driven by the engine body 2, so that the high-pressure side fuel pressure starts to rise from the retained fuel pressure.

  By increasing the high-pressure side fuel pressure, fuel vapor in the high-pressure side fuel supply mechanism 80 is eliminated. Further, the high-pressure side fuel pressure further rises and reaches the required fuel pressure for the load demand start and stabilizes.

  When the high-pressure side fuel pressure reaches the required fuel pressure and stabilizes, misfire (rotation stop) and rough idle (fluctuation of the idling speed) of the engine body 2 are prevented.

  At time T0, the ECU 140 prohibits the engine body 2 from being intermittently stopped and the operation lever 955 of the shift selector 954 is locked in the P range in accordance with the start of the engine body 2.

  This prevents the engine main body 2 from stopping intermittently while the high-pressure side fuel pressure is increasing. Further, the hybrid vehicle 100 is prevented from traveling before the operation lever 955 of the shift selector 954 is operated to the D range and the high-pressure side fuel pressure rises and stabilizes.

  At time T1, the engine body 2 reaches the idle speed, and at time T2, the high-pressure side fuel pressure reaches the required fuel pressure. The ECU 140 determines that the high-pressure side fuel pressure has risen to the required fuel pressure and is stable at time T3, which is 2 seconds after the high-pressure side fuel pressure reaches the required fuel pressure at time T2.

  At time T3, the ECU 140 permits the intermittent prohibition of the engine body 2 and unlocks the shift selector 954. Although omitted in FIG. 5, the runnable indicator is lit at time T3.

  Accordingly, at time T3, the shift selector 954 is unlocked, so that the driver can move the operation lever 955 to the D range and start running the hybrid vehicle 100.

  After time T3, since the high-pressure side fuel pressure rises to the required fuel pressure and is in a stable state, when the ECU 140 starts the load request of the engine body 2 with the required driving force according to the driver's accelerator operation. Moreover, the engine body 2 can generate an engine output corresponding to the required driving force.

  In addition, when the ECU 140 starts a load request for the engine main body 2, the engine main body 2 can generate an engine output corresponding to the required driving force, so that drivability can be improved.

  As described above, according to the control device for hybrid vehicle 100 in accordance with the present embodiment, when the startup operation for making hybrid vehicle 100 travelable is performed when engine 1 is in a high temperature state, Since the engine body 2 is started in response to the start operation and the engine body 2 is not intermittently stopped, the engine body 2 is started in response to the start operation, so that the high pressure using the engine body 2 as a drive source Since the side fuel supply mechanism 80 increases the fuel pressure of the fuel, the fuel vapor can be quickly eliminated, and the fuel can be boosted to the fuel pressure required when starting the engine body 2 in response to a request for driving force. it can.

  Moreover, by prohibiting the intermittent stop of the engine body 2, it is possible to prevent the engine body 2 from being intermittently stopped and the increase in fuel pressure being interrupted. For this reason, the fuel pressure of the fuel can be increased and stabilized prior to the load request start for starting the engine body 2 in response to the request for the driving force. Therefore, engine output corresponding to the required driving force can be generated at the time of starting the load request, and drivability can be improved.

  Further, according to the control device for hybrid vehicle 100 according to the present embodiment, engine body 2 is started in response to the start operation, and the fuel pressure of the fuel supplied to engine body 2 by high-pressure side fuel supply mechanism 80 is the engine body. Since the engine main body 2 is prohibited from being intermittently stopped until the fuel pressure is increased to the required fuel pressure required for the load demand start of 2 and stabilized, the intermittent operation of the engine main body 2 is continued until the fuel fuel pressure rises to the required fuel pressure and stabilizes. Stopping is prohibited, and the fuel pressure of the fuel can be quickly raised and stabilized to the required fuel pressure.

  In addition, according to the control device for hybrid vehicle 100 according to the present embodiment, engine body 2 is started in response to the start operation, and shift selector 954 is locked so that it cannot move from the parking range to another range. When the fuel pressure of the fuel supplied to the engine body 2 by the fuel supply mechanism 80 increases to the required fuel pressure and stabilizes, the shift selector 954 is unlocked. Therefore, the shift is continued until the fuel pressure of the fuel rises to the required fuel pressure and stabilizes. Since the selector 954 is locked to the parking range, it is possible to prevent the hybrid vehicle 100 from traveling in a state where the driver's body before the fuel pressure rises to the required fuel pressure and stabilizes is not sufficient.

  Further, according to the control device for hybrid vehicle 100 according to the present embodiment, fuel supply device 5 raises the fuel pressure of the fuel by the electric power supplied from the battery and injects the fuel into intake port 21 of engine body 2. Since the low pressure side fuel supply mechanism 50 is further provided, the knocking improvement effect and the volumetric efficiency of the intake air are improved by injecting the fuel into the combustion chamber 16 of the engine body 2, and the fuel is injected into the intake port 21 of the engine body 2. Thus, the homogeneity of the air-fuel mixture can be improved at the same time.

  As described above, the control device for a hybrid vehicle according to the present invention produces an engine output corresponding to the required driving force when the load request is started, and has the effect of improving drivability. This is useful for a control device of a hybrid vehicle equipped with an injection type engine.

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Engine main body, 5 ... Fuel supply device, 16 ... Combustion chamber, 21 ... Intake port, 50 ... Low-pressure side fuel supply mechanism, 61c ... Cooling water temperature sensor, 80 ... High-pressure side fuel supply mechanism, 81 ... High pressure pump unit, 83 ... High pressure side delivery pipe, 84 ... High pressure side injector, 100 ... Hybrid vehicle, 140 ... ECU (control device), 950 ... Ignition switch, 952 ... Shift lock ECU, 954 ... Shift selector, 955 ... Operating lever , 956 ... Intake air temperature sensor, 960 ... Running indicator

Claims (4)

An internal combustion engine having an internal combustion engine body and a fuel supply device for supplying fuel to the internal combustion engine body, and an electric motor driven by electric power supplied from a battery,
The fuel supply device has a high-pressure side fuel supply mechanism that uses the internal combustion engine body as a drive source to increase the fuel pressure of the fuel and injects the fuel into the cylinder of the internal combustion engine body;
A control device for a hybrid vehicle capable of traveling by at least one of a driving force generated by the internal combustion engine body and a driving force generated by the electric motor,
When the internal combustion engine is in a high temperature state and a start operation for making the hybrid vehicle ready to run is performed, the internal combustion engine body is started in response to the start operation, and the internal combustion engine body is intermittently operated. A control apparatus for a hybrid vehicle, which prohibits stoppage.   The internal combustion engine main body is started in response to the starting operation, and the fuel pressure of the fuel supplied to the internal combustion engine main body by the fuel supply device is increased to a required fuel pressure required for the load request start of the internal combustion engine main body and stabilized. 2. The hybrid vehicle control device according to claim 1, wherein the internal combustion engine main body is prohibited from being intermittently stopped until the operation is completed. Moving when the shift selector is a parking range, while starting the internal combustion engine main body in response to the starting operation, when the internal combustion engine is high state, the shift selector to another range from the parking range lock so that it can not, when the fuel supply system is stabilized by boosting the fuel pressure the request fuel pressure of fuel supplied to the internal combustion engine body, the 請 Motomeko 2 you and cancels the lock of the shift selector The hybrid vehicle control apparatus described.   2. The fuel supply apparatus according to claim 1, further comprising a low-pressure side fuel supply mechanism that increases fuel pressure of fuel by electric power supplied from the battery and injects fuel into an intake port of the internal combustion engine body. The control apparatus of the hybrid vehicle in any one of Claim 3.

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