Engine equipment

Abstract

To achieve both a torque requirement to an engine and favorable explosion combustion of the engine even before the complete engagement of a clutch by starting the engine.SOLUTION: A control device starts injecting fuel to an engine and igniting the engine while increasing a rotation number of the engine by bringing a clutch into a semi-engagement state, and after that, when the rotation number of the engine coincide with a rotation number of a motor, the control device brings the clutch into a complete engagement state. At this time, at the throttling and the ignition of the engine, a torque requirement to the engine is performed even before the complete engagement of the clutch. When the rotation number of the engine is equal to or larger than a prescribed rotation number, control is shifted to torque control from start-time control, and at the fuel injection of the engine, the control is shifted to the torque control from the start-time control after the transition to the torque control with respect to the throttling and ignition timing.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an engine device, and more particularly to an engine device including an engine having a direct injection valve and a motor connected to an output shaft of the engine via a clutch. [Background technology]

[0002] Conventionally, as this type of engine device, a hybrid vehicle equipped with an engine, a motor connected to the output shaft of the engine via a clutch, and an automatic transmission connected to the rotating shaft of the motor and an axle has been proposed (see, for example, Patent Document 1). In this hybrid vehicle, the engine is started with the clutch in slip engagement, and when the engine speed reaches or exceeds a predetermined speed, engine control is shifted to torque control, and then the torque is suppressed by retarding the ignition timing to fully engage the slip engagement clutch. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-028304 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the engine device mounted on the above-mentioned hybrid vehicle, there are cases where the explosive combustion of the engine 22 becomes unstable simply by retarding the ignition timing. Since priority is given to fuel efficiency in the torque control of fuel injection, retarding the ignition timing may result in poor explosive combustion.

[0005] The engine device of the present invention is an engine device having an engine and a motor connected to the output shaft of the engine via a clutch, and its main object is to achieve both the torque requirements for the engine and good explosive combustion in the engine even before the engine is started and the clutch is fully engaged. [Means for solving the problem]

[0006] In order to achieve the above-mentioned main object, the engine device of the present invention employs the following means.

[0007] The engine device of the present invention comprises: An engine device including an engine having an in-cylinder injection valve, a motor connected to an output shaft of the engine via a clutch, and a control device that controls the engine, the motor, and the clutch, the control device controls the engine, the motor, and the clutch so that, when the engine is stopped due to a fuel cut or has a lower rotation speed than the motor, the control device half-engages the clutch and starts fuel injection and ignition while increasing the rotation speed of the engine by the motor, and then, while maintaining the half-engagement of the clutch or releasing the half-engagement of the clutch, the engine rotation speed matches the motor rotation speed, and fully engages the clutch when the engine rotation speed approximately matches the motor rotation speed; The control device includes: With regard to the throttle and ignition of the engine, when a torque request is made to the engine even before the clutch is fully engaged and the engine speed is equal to or higher than a predetermined speed, a transition is made from a start-up control at the time of start-up to a torque control corresponding to the torque request of the engine; Regarding fuel injection of the engine, the control is shifted from the start-up control to the torque control after the throttle and ignition timing are shifted to the torque control. It is characterized by:

[0008] The engine device of the present invention includes an engine having an in-cylinder injection valve, a motor connected to an output shaft of the engine via a clutch, and a control device that controls the engine, the motor, and the clutch. The control device controls the engine, the motor, and the clutch so that, when the engine is stopped due to a fuel cut or is at a lower rotation speed than the motor's rotation speed, the control device half-engages the clutch and starts fuel injection and ignition while increasing the engine rotation speed by the motor, and then controls the engine, the motor, and the clutch so that the engine rotation speed matches the motor rotation speed with the clutch kept half-engaged or with the clutch half-engaged released, and fully engages the clutch when the engine rotation speed approximately matches the motor rotation speed. The control device also transitions from start-up control at the time of starting the engine throttle and ignition to torque control corresponding to the torque request of the engine when a torque request to the engine is being made even before the clutch is fully engaged and the engine rotation speed is equal to or higher than a predetermined rotation speed, and transitions from start-up control to torque control for the engine fuel injection after transitioning to torque control for the throttle and ignition timing. The start-up control basically controls the throttle opening, ignition timing, fuel injection amount, and fuel injection timing so that stable explosive combustion occurs in each cylinder, while the torque control basically controls the throttle opening, ignition timing, fuel injection amount, and fuel injection timing so that the required torque is output from the engine. Even before the clutch is fully engaged, when a torque request is made to the engine and the engine speed is equal to or higher than a predetermined speed, the throttle and ignition control are switched from the start-up control to the torque control, but the fuel injection is maintained at the start-up control, thereby making it possible to achieve both the torque request to the engine and good explosive combustion in the engine. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing an outline of the configuration of a hybrid vehicle 20 according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an outline of the configuration of an engine 22. [Diagram 3]4 is a flowchart showing an example of a startup process executed by the HVECU 70, the engine ECU 24, etc. [Figure 4] This is an explanatory diagram showing an example of the time changes in the engine 22 rotation speed Ne at the start of the engine 22, permission to transition to torque control, the presence or absence of a torque request, the state of whether the clutch K0 is fully engaged, and the control state of the throttle, ignition, and fuel injection. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Next, an embodiment of the present invention will be described with reference to the accompanying drawings. EXAMPLES

[0011] Fig. 1 is a schematic diagram showing the configuration of a hybrid vehicle 20 equipped with an engine device according to an embodiment of the present invention. Fig. 2 is a schematic diagram showing the configuration of an engine 22 equipped in the hybrid vehicle 20. As shown in Fig. 1, the hybrid vehicle 20 of the embodiment includes the engine 22, a motor 30, an inverter 32, a clutch K0, an automatic transmission 40, a high-voltage battery 60, a low-voltage battery 62, a DC / DC converter 64, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70.

[0012] The engine 22 is configured as a six-cylinder internal combustion engine that uses fuel such as gasoline or diesel to output power through four strokes: intake, compression, expansion (explosive combustion), and exhaust. As shown in FIG. 2, the engine 22 has a port injection valve 126 that injects fuel into an intake port, and an in-cylinder injection valve 127 that injects fuel into a cylinder. The engine 22 can be operated in any one of a port injection mode, an in-cylinder injection mode, and a common injection mode by having the port injection valve 126 and the in-cylinder injection valve 127. In the port injection mode, air purified by the air cleaner 122 is sucked into the intake pipe 123 and passes through the throttle valve 124 and the surge tank 125, and fuel is injected from the port injection valve 126 downstream of the surge tank 125 of the intake pipe 123, and the air and fuel are mixed. This mixture is then drawn into the combustion chamber 129 via the intake valve 128, where it is explosively combusted by an electric spark from the spark plug 130, and the reciprocating motion of the piston 132, which is pushed down in the cylinder bore by the energy of the mixture, is converted into the rotational motion of the crankshaft 23. In the in-cylinder injection mode, air is drawn into the combustion chamber 129 in the same manner as in the port injection mode, and fuel is injected from the in-cylinder injection valve 127 during the intake stroke and compression stroke, and is explosively combusted by an electric spark from the spark plug 130, to obtain the rotational motion of the crankshaft 23. In the shared injection mode, fuel is injected from the port injection valve 126 when air is drawn into the combustion chamber 129, and fuel is injected from the in-cylinder injection valve 127 during the intake stroke and compression stroke, and is explosively combusted by an electric spark from the spark plug 130, to obtain the rotational motion of the crankshaft 23. These injection modes are switched based on the operating state of the engine 22. Exhaust discharged from the combustion chamber 129 to an exhaust pipe 134 via an exhaust valve 133 is discharged into the outside air via a purification device 135 and a PM filter 136. The purification device 135 has a purification catalyst (three-way catalyst) 135a that purifies harmful components in the exhaust such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). The PM filter 136 is formed as a porous filter from ceramics, stainless steel, or the like, and collects particulate matter (PM) such as soot in the exhaust.In place of the PM filter 136, a four-way catalyst that combines the purification function of a three-way catalyst with the function of trapping particulate matter may be used.

[0013] The operation of the engine 22 is controlled by the engine ECU 24. The engine ECU 24 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, not shown. Signals from various sensors required for controlling the operation of the engine 22 are input to the engine ECU 24 via input ports. Examples of signals input to the engine ECU 24 include a crank angle θcr from a crank position sensor 140 that detects the rotational position of the crankshaft 23 of the engine 22, and a cooling water temperature Tw from a water temperature sensor 142 that detects the temperature of the cooling water of the engine 22. Other examples of signals input to the engine ECU 24 include cam angles θci and θco from a cam position sensor 144 that detects the rotational position of an intake camshaft that opens and closes the intake valve 128 and the rotational position of an exhaust camshaft that opens and closes the exhaust valve 133. Other examples of the above include the throttle opening TH from a throttle valve position sensor 124a that detects the position of the throttle valve 124, the intake air amount Qa from an air flow meter 123a attached upstream of the throttle valve 124 of the intake pipe 123, the intake air temperature Ta from a temperature sensor 123t attached upstream of the throttle valve 124 of the intake pipe 123, and the surge pressure Ps from a pressure sensor 125a attached to the surge tank 125. Other examples of the above include a front air-fuel ratio AF1 from a front air-fuel ratio sensor 137 attached upstream of the purification device 135 of the exhaust pipe 134, a rear air-fuel ratio AF2 from a rear air-fuel ratio sensor 138 attached between the purification device 135 of the exhaust pipe 134 and the PM filter 136, and a differential pressure ΔP from a differential pressure sensor 136a that detects a differential pressure before and after the PM filter 136 (a differential pressure between the upstream side and the downstream side).

[0014] From the engine ECU 24, various control signals for controlling the operation of the engine 22 are output via an output port. Examples of signals output from the engine ECU 24 include a control signal to a throttle valve 124, a control signal to a port injection valve 126, a control signal to an in-cylinder injection valve 127, and a control signal to an ignition plug 130.

[0015] The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr of the engine 22 from the crank position sensor 140. The engine ECU 24 also calculates a load factor KL (the ratio of the volume of air actually taken in one cycle to the stroke volume per cycle of the engine 22) based on the intake air amount Qa from the air flow meter 123a and the rotation speed Ne of the engine 22. Furthermore, the engine ECU 24 calculates a PM accumulation amount Qpm as the accumulation amount of particulate matter accumulated on the PM filter 136 based on a differential pressure ΔP from the differential pressure sensor 136a, and calculates a filter temperature Tf as the temperature of the PM filter 136 based on the rotation speed Ne of the engine 22 and the load factor KL.

[0016] 1, a starter motor 25 for cranking the engine 22 and an alternator 26 for generating power using power from the engine 22 are connected to the crankshaft 23 of the engine 22. The starter motor 25 and the alternator 26 are connected to a low-voltage power line 63 together with a low-voltage battery 62, and are controlled by the HVECU 70.

[0017] The motor 30 is configured as a synchronous generator motor, and has a rotor in which a permanent magnet is embedded in a rotor core, and a stator in which a three-phase coil is wound around a stator core. A rotating shaft 31 to which the rotor of the motor 30 is fixed is connected to the crankshaft 23 of the engine 22 via a clutch K0, and is also connected to an input shaft 41 of an automatic transmission 45. The inverter 32 is used to drive the motor 30, and is connected to a high-voltage power line 61. The motor 30 is rotationally driven by a motor electronic control unit (hereinafter referred to as "motor ECU") 34 controlling the switching of multiple switching elements of the inverter 32.

[0018] The motor ECU 34 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, not shown. Signals from various sensors are input to the motor ECU 34 via the input ports. Examples of signals input to the motor ECU 34 include a rotational position θm from a rotational position sensor 30a that detects the rotational position of the rotor (rotating shaft 31) of the motor 30, and phase currents Iu and Iv from current sensors that detect the phase currents of the respective phases of the motor 30. A control signal to the inverter 32 and the like are output from the motor ECU 34 via the output port. The motor ECU 34 is connected to the HVECU 70 via a communication port. The motor ECU 34 calculates the rotational speed Nm of the motor 30 based on the rotational position θm of the rotor (rotating shaft 31) of the motor 30 from the rotational position sensor 30a.

[0019] The clutch K0 is configured as, for example, a hydraulically driven friction clutch, and is controlled by the HVECU 70 to connect and disconnect the crankshaft 23 of the engine 22 and the rotating shaft 31 of the motor 30.

[0020] The automatic transmission 40 has a torque converter 43 and an automatic transmission 45 with, for example, six speeds. The torque converter 43 is configured as a general fluid transmission device, and transmits the power of an input shaft 41 connected to a rotating shaft 31 of the motor 30 to a transmission input shaft 44 which is an input shaft of the automatic transmission 45 with amplified torque, or transmits the torque as is without amplifying it. The automatic transmission 45 has the transmission input shaft 44, an output shaft 42 connected to driving wheels 49 via a differential gear 48, a plurality of planetary gears, and a plurality of hydraulically driven friction engagement elements (clutches, brakes). Each of the plurality of friction engagement elements has a hydraulic servo configured of a piston, a plurality of friction engagement plates (friction plates and separator plates), an oil chamber to which hydraulic oil is supplied, and the like. The automatic transmission 45 forms forward gears from 1st gear to 6th gear and reverse gears by engaging and disengaging a plurality of friction engagement elements, and transmits power between the transmission input shaft 44 and the output shaft 42. The hydraulic pressure of hydraulic oil from a mechanical oil pump or an electric oil pump is adjusted and supplied to the clutch K0 and the automatic transmission 45 by a hydraulic control device (not shown). The hydraulic control device has a valve body with a plurality of oil passages formed therein, a plurality of regulator valves, a plurality of linear solenoid valves, etc. This hydraulic control device is controlled by the HVECU 70.

[0021] High-voltage battery 60 is configured as, for example, a lithium-ion secondary battery or a nickel-hydrogen secondary battery with a rated voltage of several hundred volts, and is connected to high-voltage power line 61 together with inverter 32. Low-voltage battery 62 is configured as, for example, a lead-acid battery with a rated voltage of about 12 V or 14 V, and is connected to low-voltage power line 63 together with starter motor 25 and alternator 26. DC / DC converter 64 is connected to high-voltage power line 61 and low-voltage power line 63. This DC / DC converter 64 supplies power from high-voltage power line 61 to low-voltage power line 63 with a voltage step-down.

[0022] Although not shown, the HVECU 70 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port. Signals from various sensors are input to the HVECU 70 via the input port. Examples of signals input to the HVECU 70 include the rotation speed Nin from the rotation speed sensor 41a attached to the input shaft 41 of the automatic transmission 40, the rotation speed Nmi from the rotation speed sensor 44a attached to the transmission input shaft 44 of the automatic transmission 40, and the rotation speed Nout from the rotation speed sensor 42a attached to the output shaft 42 of the automatic transmission 40. Examples of signals input to the HVECU 70 include the voltage Vbh of the high-voltage battery 60 from a voltage sensor attached between the terminals of the high-voltage battery 60, the current Ibh of the high-voltage battery 60 from a current sensor attached to the output terminal of the high-voltage battery 60, and the voltage Vbl from a voltage sensor attached between the terminals of the low-voltage battery 62. Other examples of such signals include an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operating position of a shift lever 81, an accelerator opening Acc from an accelerator pedal position sensor 84 that detects the amount of depression of an accelerator pedal 83, a brake pedal position BP from a brake pedal position sensor 86 that detects the amount of depression of a brake pedal 85, and a vehicle speed V from a vehicle speed sensor 87.

[0023] Various control signals are output from the HVECU 70 via an output port. Examples of signals output from the HVECU 70 include a control signal to the starter motor 25 and a control signal to the alternator 26. Examples of signals output from the HVECU 70 include a control signal to the clutch K0 and the automatic transmission 40 (hydraulic control device), and a control signal to the DC / DC converter 64. The HVECU 70 is connected to the engine ECU 24 and the motor ECU 34 via a communication port. The HVECU 70 calculates a rotation speed ratio Gt of the automatic transmission 40 by dividing the rotation speed Nin of the input shaft 41 of the automatic transmission 40 from the rotation speed sensor 41a by the rotation speed Nout of the output shaft 42 of the automatic transmission 40 from the rotation speed sensor 42a.

[0024] In the hybrid vehicle 20 of the embodiment thus configured, the engine 22, the clutch K0, the motor 30, and the automatic transmission 40 are controlled by cooperative control between the HVECU 70, the engine ECU 24, and the motor ECU 34 so as to travel in a hybrid driving mode (HV driving mode) or an electric driving mode (EV driving mode). Here, the HV driving mode is a mode in which the clutch K0 is in an engaged state and the vehicle travels using the power of the engine 22, and the EV driving mode is a mode in which the clutch K0 is in a released state and the vehicle travels without using the power of the engine 22.

[0025] In controlling the automatic transmission 40 in the HV driving mode or the EV driving mode, the HVECU 70 first sets a target gear M* of the automatic transmission 45 based on the accelerator opening Acc and the vehicle speed V. Then, when the gear M of the automatic transmission 45 matches the target gear M*, the HVECU 70 controls the automatic transmission 45 so that the gear M is maintained. On the other hand, when the gear M and the target gear M* differ, the HVECU 70 controls the automatic transmission 45 so that the gear M matches the target gear M*.

[0026] In controlling the engine 22 and the motor 30 in the HV driving mode, the HVECU 70 first sets a required torque Tout* required for driving (required of the output shaft 42 of the automatic transmission 40) based on the accelerator opening Acc and the vehicle speed V. Next, the required torque Tout* of the output shaft 42 is divided by the rotation speed ratio Gt of the automatic transmission 40, and the value is set as the required torque Tin* of the input shaft 41. After setting the required torque Tin* of the input shaft 41 in this manner, the HVECU 70 sets a target torque Te* of the engine 22 and a torque command Tm* of the motor 30 so that the required torque Tin* is output to the input shaft 41, and transmits the target torque Te* of the engine 22 to the engine ECU 24 and transmits the torque command Tm* of the motor 30 to the motor ECU 34. Upon receiving the target torque Te*, the engine ECU 24 performs operation control of the engine 22 (intake air amount control, fuel injection control, ignition control, etc.) so that the engine 22 is operated at the target torque Te*. When the motor ECU 34 receives the torque command Tm*, it performs switching control of a plurality of switching elements of the inverter 32 so that the motor 30 is driven by the torque command Tm*.

[0027] In controlling the motor 30 in the EV driving mode, the HVECU 70 sets a required torque Tin* of the input shaft 41 in the same manner as in the HV driving mode, sets a torque command Tm* of the motor 30 so that the required torque Tin* is output to the input shaft 41, and transmits the torque command Tm* to the motor ECU 34. Upon receiving the torque command Tm*, the motor ECU 34 performs switching control of a plurality of switching elements of the inverter 32 so that the motor 30 is driven by the torque command Tm*.

[0028] In this embodiment, the engine device corresponds to the engine 22, the clutch K0, the motor 30, the HVECU 70, the engine ECU 24, and the motor ECU .

[0029] Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly the start of the engine 22 when the engine 22 is intermittently operated, will be described. The start of the intermittently stopped engine 22 can be considered as starting the engine 22 that is completely stopped, or starting the engine 22 while the engine speed Ne of the engine 22 is decreasing due to fuel cut in order to intermittently stop the engine 22. Fig. 3 is a flowchart showing an example of a start-time process executed by the engine ECU 24 and the HVECU 70 when starting the intermittently stopped engine 22.

[0030] When the start-up process is executed, first, the clutch K0 is half-engaged (slip-engaged) to output the target cranking torque Tcr* from the motor 30 to start cranking the engine 22 (step S100). This process is performed by transmitting a control signal from the HVECU 70 to a hydraulic control device (not shown) so that the clutch K0 is half-engaged (slip-engaged), and transmitting the sum of the required torque Tin* required for the input shaft 41 and the target cranking torque Tcr* to the motor ECU 34 as a torque command Tm* for the motor 30. The hydraulic control device that has received the control signal adjusts the hydraulic pressure to a predetermined level so that the clutch K0 can transmit the target cranking torque Tcr* while slipping. The motor ECU 34 that has received the torque command Tm* controls the switching of a switching element (not shown) of the inverter 32 so that the torque command Tm* is output from the motor 30. When starting the engine 22 that is completely stopped, the target cranking torque Tcr* is set to a torque sufficient to cause the cylinder stopped in the compression stroke to exceed the compression top dead center, and is set based on the stop crank angle θstop and the elapsed time since the engine 22 was stopped. The reason for setting the target cranking torque Tcr* based on the stop crank angle θstop is to take into account the pressure in the cylinder stopped in the compression stroke, and the reason for setting the target cranking torque Tcr* based on the elapsed time since the engine 22 was stopped is to take into account the pressure in the cylinder stopped in the compression stroke decreasing over time. On the other hand, when starting the engine 22 whose rotation speed has been reduced by fuel cut, the target cranking torque Tcr* is set to a torque sufficient to increase the rotation speed Ne of the engine 22, and is determined based on the rotation speed Ne of the engine 22, etc.

[0031] At the same time as cranking of the engine 22, start-up control of fuel injection and throttle / ignition is started (step S110). The start-up control of fuel injection corresponds to, for example, control for setting a fuel injection amount and a fuel injection timing in a compression stroke such that good explosive combustion occurs for an estimated amount of air in the cylinder from the first explosive combustion (initial explosion) to a first predetermined number of explosive combustions (e.g., 10, 12, 15, etc.), and control for setting a fuel injection amount and a fuel injection timing in an intake stroke and a compression stroke such that good explosive combustion occurs for an estimated amount of air in the cylinder for a second predetermined number of explosive combustions thereafter (e.g., 10, 12, 15, etc.). The start-up control of the throttle corresponds to, for example, control for setting a throttle opening based on the rotation speed Ne of the engine 22 and the rotation speed Nmg of the motor 30 so that the rotation speed Ne of the engine 22 approaches the rotation speed Nmg of the motor 30. An example of ignition start-up control is a control in which a retarded ignition timing is set to suppress shock for the initial explosive combustion (initial explosion), and then the ignition timing is set based on the rotation speed Ne of the engine 22 and the rotation speed Nmg of the motor 30 so that the rotation speed Ne of the engine 22 approaches the rotation speed Nmg of the motor 30.

[0032] Next, the hydraulic control device waits until the condition for releasing the clutch K0 is satisfied (step S120), and the clutch K0 is released by controlling the hydraulic control device to wait at a hydraulic pressure that does not cause the clutch K0 to slip (step S130). Examples of the condition for releasing the clutch K0 include a condition that the compression top dead center has been passed a predetermined number of times (e.g., 2 or 3 times), a condition that the rotation speed Ne of the engine 22 is increasing, and a condition that the rotation speed Ne of the engine 22 is equal to or higher than a threshold value based on the rotation speed Nmg of the motor 30. In the embodiment, it is determined that the condition for releasing the clutch K0 is satisfied when all of the above three conditions are satisfied.

[0033] When the clutch K0 is released, it is determined whether or not the control for the throttle and ignition has shifted from the start-up control to the torque control for outputting the requested torque from the engine 22 (step S140). When it is determined that the control for the throttle and ignition has not shifted from the start-up control to the torque control, it is determined whether or not both of the conditions that the torque request to the engine 22 is made and that the rotation speed Ne of the engine 22 is equal to or higher than a predetermined rotation speed Nref (for example, 1000 rpm or 1200 rpn) are satisfied as the conditions for shifting from the start-up control to the torque control for the throttle and ignition (step S150, S160), and when the conditions for shifting from the start-up control to the torque control for the throttle and ignition are satisfied, the control for the throttle and ignition is shifted from the start-up control to the torque control for the throttle and ignition (step S170). The torque control for the throttle is a control for controlling the throttle opening so as to output the torque requested from the engine 22 in response to the torque request, and the torque control for the ignition is a control for setting the ignition timing so as to output the torque requested from the engine 22 in response to the torque request. If it is determined in steps S150 and S160 that the conditions for transitioning from start-up control to torque control for the throttle and ignition are not satisfied, the transition to torque control in step S170 is not performed. Also, if it is determined in step S140 that the transition from start-up control to torque control for the throttle and ignition is being performed, the processing of steps S150 to S170 is not performed. Then, it is determined whether the conditions for engaging the clutch K0 are satisfied (step S180), and if it is determined that the conditions for engaging the clutch K0 are not satisfied, the processing returns to step S140. Therefore, steps S140 to S180 are processing for transitioning from start-up control to torque control for the throttle and ignition when the conditions for transitioning from start-up control to torque control for the throttle and ignition are satisfied before the conditions for engaging the clutch K0 are satisfied.There may be cases where the conditions for shifting from start-up control to torque control for the throttle and ignition are not satisfied before the conditions for engaging the clutch K0 are satisfied, but in that case, when the conditions for engaging the clutch K0 are satisfied, it is assumed that the conditions for shifting from start-up control to torque control for the throttle and ignition are also satisfied, and the control shifts from start-up control to torque control. Note that, as the conditions for engaging the clutch K0, for example, a condition that the differential rotation speed ΔN between the rotation speed Ne of the engine 22 and the rotation speed Nmg of the motor 30 is less than a threshold value (e.g., 50 rpm, 100 rpm, 150 rpm, etc.) and the number of ignitions is equal to or greater than a predetermined number (e.g., 5 times, 6 times, 8 times, etc.) can be used.

[0034] When it is determined in step S180 that the condition for engaging the clutch K0 is satisfied, the clutch K0 is engaged (step S190), and the process waits for the condition for transitioning from start-up control to torque control for fuel injection to be satisfied (step S200), and the fuel injection is also transitioned to torque control (step S210), and ends this process. The condition for transitioning from start-up control to torque control for fuel injection can be, for example, a condition that the number of explosive combustions since the start of engine 22 startup is equal to or greater than a predetermined number (e.g., 20, 25, 30, etc.). The torque control of fuel injection includes not only fuel injection from in-cylinder injection valve 127 during the intake stroke and compression stroke, but also injection from port injection valve 126 in consideration of fuel economy.

[0035] 4 is an explanatory diagram showing an example of the rotation speed Ne of the engine 22 at the start of the engine 22, permission to shift to torque control, presence or absence of torque request, state of whether the clutch K0 is fully engaged, and time change in the control state of the throttle, ignition, and fuel injection. In the figure, the dashed line at the rotation speed Ne of the engine 22 indicates the rotation speed Nmg of the motor 30. At time T1, cranking of the engine 22 is started with the throttle, ignition, and fuel injection all in the start-up control state, and at time T2 when the rotation speed Ne of the engine 22 has increased to a certain degree, torque control is permitted. The permission of torque control can be performed, for example, when the rotation speed Ne of the engine 22, which is a condition for shifting from the start-up control to the torque control, reaches or exceeds a predetermined rotation speed Nref (for example, 1000 rpm or 1200 rpn) or reaches or exceeds a rotation speed slightly smaller than the predetermined rotation speed Nref. Thereafter, when the engine 22 speed Ne is equal to or higher than a predetermined speed at time T3 when the torque request is made, the throttle and ignition are shifted from start-up control to torque control, but the fuel injection is maintained at start-up control. This satisfies the torque request for the engine 22 and ensures good explosive combustion in the engine 22. The clutch K0 is fully engaged at time T4 when the engine 22 speed Ne approximately matches the motor 30 speed Nmg, and then, at time T5 when the condition for shifting to torque control for fuel injection is met, the fuel injection also shifts to torque control.

[0036] In the engine device mounted on the hybrid vehicle 20 of the embodiment described above, the clutch K0 is half-engaged (slip-engaged) to output the target cranking torque Tcr* from the motor 30 to start cranking of the engine 22, and start-up control of fuel injection, throttle, and ignition is started to start the engine 22, and the clutch K0 is released by controlling the clutch K0 to wait at a hydraulic pressure that does not slip when a condition for releasing the clutch K0 is satisfied. The clutch K0 is then fully engaged when a condition for engaging the clutch K0 is satisfied, such as the differential rotation speed ΔN between the rotation speed Ne of the engine 22 and the rotation speed Nmg of the motor 30 being less than a threshold value. When both a condition that a torque request is made to the engine 22 and a condition that the rotation speed Ne of the engine 22 is equal to or greater than a predetermined rotation speed Nref are satisfied as conditions for transitioning from the start-up control to the torque control for the throttle and ignition between the release of the clutch K0 and the complete engagement of the clutch K0, the throttle and ignition transition from the start-up control to the torque control, but the fuel injection is maintained as the start-up control. This makes it possible to satisfy both the torque demand for the engine and good explosive combustion in the engine.

[0037] In the hybrid vehicle 20 of the embodiment, when starting the engine 22 that has been intermittently stopped, the clutch K0 is half-engaged (slip engaged) to crank the engine 22 to start the engine 22, and then the clutch K0 is released to bring the rotation speed Ne of the engine 22 closer to the rotation speed Nmg of the motor 30, and the clutch K0 is fully engaged when the rotation speed Ne of the engine 22 approximately matches the rotation speed Nmg of the motor 30. However, the clutch K0 may be kept half-engaged (slip engaged) even after the engine 22 is started to bring the rotation speed Ne of the engine 22 closer to the rotation speed Nmg of the motor 30, and the clutch K0 may be fully engaged when the rotation speed Ne of the engine 22 approximately matches the rotation speed Nmg of the motor 30.

[0038] The hybrid vehicle 20 of the embodiment is equipped with a six-speed automatic transmission 45. However, it may be equipped with a four-speed, five-speed, eight-speed, or other automatic transmission.

[0039] The hybrid vehicle 20 of the embodiment includes the engine ECU 24, the motor ECU 34, and the HVECU 70. However, at least two of these may be integrated into one unit.

[0040] Although the engine device of the embodiment is mounted on the hybrid vehicle 20, it may be mounted on a moving body other than a vehicle, or may be incorporated into equipment.

[0041] The relationship between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem will be described below. In the embodiment, the engine 22 corresponds to the "engine", the clutch K0 corresponds to the "clutch", the motor 30 corresponds to the "motor", and the HVECU 70, the engine ECU 24, and the motor ECU 34 correspond to the "control device".

[0042] The correspondence between the main elements of the Examples and the main elements of the invention described in the Summary of the Problem column does not limit the elements of the invention described in the Summary of the Problem column, since the Examples are examples for specifically explaining the mode for implementing the invention described in the Summary of the Problem column. In other words, the interpretation of the invention described in the Summary of the Problem column should be based on the description in that column, and the Examples are merely a specific example of the invention described in the Summary of the Problem column.

[0043] Although the form for carrying out the present invention has been described above using examples, the present invention is not limited to these examples in any way, and it goes without saying that the present invention can be carried out in various forms without departing from the scope of the gist of the present invention. [Industrial Applicability]

[0044] The present invention can be used in the engine device manufacturing industry and the like. [Explanation of symbols]

[0045] 20 hybrid vehicle, 22 engine, 23 crankshaft, 24 engine ECU, 25 starter motor, 26 alternator, 30 motor, 30a rotational position sensor, 31 rotating shaft, 32 inverter, 34 motor ECU, 40 automatic transmission, 41 input shaft, 41a rotational speed sensor, 42 output shaft, 42a rotational speed sensor, 43 torque converter, 44 transmission input shaft, 44a rotational speed sensor, 45 automatic transmission, 48 differential gear, 49 drive wheel, 60 high voltage battery, 61 high voltage side power line, 62 low voltage battery, 63 low voltage side power line, 64 DC / DC converter, 70 HVECU, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 Brake pedal position sensor, 87 vehicle speed sensor, 122 air cleaner, 123 intake pipe, 123a air flow meter, 123t temperature sensor, 124 throttle valve, 124a throttle valve position sensor, 125 surge tank, 125a pressure sensor, 126 port injection valve, 127 in-cylinder injection valve, 128 intake valve, 129 combustion chamber, 130 spark plug, 132 piston, 133 exhaust valve, 134 exhaust pipe, 135 purification device, 135a purification catalyst, 136 PM filter, 136a differential pressure sensor, 137 front air-fuel ratio sensor, 138 rear air-fuel ratio sensor, 140 crank position sensor, 142 water temperature sensor, 144 cam position sensor, K0 clutch.

Claims

[Claim 1] An engine device including an engine having an in-cylinder injection valve, a motor connected to an output shaft of the engine via a clutch, and a control device that controls the engine, the motor, and the clutch, the control device controls the engine, the motor, and the clutch so that, when the engine is stopped due to a fuel cut or has a lower rotation speed than the motor, the control device half-engages the clutch and starts fuel injection and ignition while increasing the rotation speed of the engine by the motor, and then, while maintaining the half-engagement of the clutch or releasing the half-engagement of the clutch, the engine rotation speed matches the motor rotation speed, and fully engages the clutch when the engine rotation speed approximately matches the motor rotation speed; The control device includes: With regard to the throttle and ignition of the engine, when a torque request is made to the engine even before the clutch is fully engaged and the engine speed is equal to or higher than a predetermined speed, a transition is made from a start-up control at the time of start-up to a torque control corresponding to the torque request of the engine; Regarding fuel injection of the engine, the control is shifted from the start-up control to the torque control after the throttle and ignition timing are shifted to the torque control. An engine device characterized by:

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