JP3991882B2 - POWER OUTPUT DEVICE, ITS CONTROL METHOD, AND VEHICLE - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to a technical field of a power output device including an engine and the like, a control method thereof, and a vehicle equipped with the power output device.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, hybrid type power output devices that are suitably mounted on so-called hybrid vehicles have been developed. This type of hybrid power output apparatus typically includes an engine, a motor generator apparatus, a clutch, a transmission, a drive shaft, and the like. Among these, the motor generator device is used as a generator for charging a battery, or supplied with power from a battery and used as an electric motor according to an operation state required for the power output device. The transmission is used to change the speed when transmitting the output of the engine or motor generator device to the drive shaft. Specifically, the transmission is disclosed in, for example, Patent Document 1. As described above, a fully-automatic synchronous mesh transmission device or the like is used. The motor generator device may be used by being connected to such a transmission. Further, the clutch is used to connect or disconnect the engine and the transmission. The transmission is provided with an input shaft that directly receives power from the engine in the clutch engaged state.
[0003]
In such a hybrid type power output apparatus, intermittent operation of the engine may be performed. Here, “intermittent operation” means that after a certain period of operation, there is a pause period for a while, and then the operation period is entered again. This is because the hybrid type power output apparatus can realize the traveling of the vehicle and the like by the cooperation of the engine and the motor generator apparatus as described above, so that it is not necessary to always operate the engine. . In this case, no fuel is consumed in the engine and no exhaust gas is exhausted from the engine during the suspension period, so the fuel consumption is reduced or the concentration of harmful substances in the exhaust gas is reduced. The remarkable effect can be obtained. The case where the engine is allowed to stop is specifically determined based on, for example, the degree of accelerator opening, the state of charge of the battery, or the like.
[0004]
[Patent Document 1]
JP-A-11-141665
[0005]
[Problems to be solved by the invention]
However, the power output apparatus as described above has the following problems. That is, when shifting from a state where the engine is stopped and the vehicle is traveling only by the motor generator device to a state where the engine is traveling alone, the engine speed (hereinafter simply referred to as “Ne”) is usually used. )) Exceeds the rotational speed of the input shaft (hereinafter sometimes simply referred to as “Ni”), the clutch is engaged. This is because if the clutch is engaged when Ne <Ni, the rotation of the input shaft is dragged by the rotation of the engine, giving the user a feeling of deceleration.
[0006]
However, when engaging the clutch after Ne> Ni, if the engine fails to start due to, for example, a small amount of fuel injection, the starter motor must be started again after the failure. I must. Then, not only is the time until then wasted, but the use of the starter motor again wastes power, and also gives the user a sense of discomfort such as starting the starter motor and subsequent vibration of the engine. It will be.
[0007]
In order to deal with such a problem, for example, when starting the engine, it is conceivable to make the fuel injection amount relatively large. According to this, since the engine can be started more reliably, a situation in which the starter motor is used again or again as described above can be avoided. However, according to such a means, the engine is blown up by a relatively large amount of fuel injection, which causes a problem that the user feels uncomfortable such as vibration. Also, this means uses a relatively large amount of fuel each time the engine is started, which is not preferable from the viewpoint of fuel efficiency, and also causes a deterioration in emissions.
[0008]
The present invention has been made in view of the above problems, and in a power output apparatus having two power sources, the other operation is executed from the state in which the operation of only one of them is performed. It is an object of the present invention to provide a power output apparatus and a control method therefor, and a vehicle including the power output apparatus that can smoothly perform this without switching the mode when the mode is switched. It is another object of the present invention to prevent waste of fuel consumption and deterioration of emissions during mode switching as described above.
[0009]
[Means for Solving the Problems]
  In order to solve the above problems, a power output device of the present invention includes an engine that outputs rotational power, and the engine.Connected to the crankshaft of the engineA starter motor to help startCrankshaftConnected or disconnected via a clutchAnd an input shaft directly connected to the clutchTransmissionWhen,A drive shaft to which the rotational power is transmitted via the transmission, and a motor generator device connected to the transmission so as to be able to drive the drive shaftAnd beforeThe engine in which the drive shaft is driven by the motor generator device and is in a stopped stateIs started by the starter motorOn the occasionStart the engine by the starter motor,Before the engine speed becomes higher than the input shaft speed, the clutch is controlled to engage the clutch, and the output of the motor generator device is output before the clutch is engaged. And a control means for controlling the motor generator device so that the motor generator device is further raised.
[0010]
  According to the power output device of the present invention,The starter motor can help to start it,For example, the output of an ignition combustion type or self-ignition combustion type engine is transmitted in the order of a clutch, a transmission, and a drive shaft. Here, the “clutch” includes, for example, a wet multi-plate hydraulic friction engagement device that is frictionally engaged by a hydraulic actuator, and the “transmission device” includes a stepped gear type such as a planetary gear type or a twin-shaft type. A transmission or a continuously variable transmission (CVT) is included. ThisengineIt is possible to take out the power generated by the above (appropriate elements may be further connected to the drive shaft).
[0011]
  In the power output device of the present invention, the drive shaft is connected to the transmission so as to be driven.Motor generator deviceIt has. thisMotor generator deviceAnd the aboveengineIs provided in the drive shaft according to the present invention.engineOnly output,Motor generator deviceOnly output, orengineas well asMotor generator deviceBoth of these outputs can be transmitted, and the drive shaft can be driven by these three methods.Here, in addition to the motor (electric motor), the motor generator device may include a generator (generator), or may include a motor generator having both functions.
[0012]
  And especially in this invention, it is a case where a drive shaft is driven by the motor generator apparatus, Comprising: The engine in the stopped stateIs started by the starter motorOn the occasionStart the engine by the starter motor,Control means is provided for controlling the clutch so that the clutch is engaged before the rotational speed of the engine becomes higher than the rotational speed of the input shaft.
[0013]
  Here, in the case where the transmission includes, for example, the input shaft, in addition to the output shaft, and a stepped transmission including each speed gear that communicates between the two shafts, the drive The shaft can be assumed as the output shaft or a shaft connected thereto. in this case,Motor generator deviceWhen the drive shaft is driven by the above, usually, the input shaft is also rotated through one of the respective speed gears. And in this invention, it is such a case,engineWhen the drive shaft is to be driven by the rotation speed of the input shaft rotating as described above,engineThe clutch is engaged in a state higher than the rotational speed of the clutch. Looking at this in reverse,engineAlthough the rotational speed of the engine is lower than the rotational speed of the input shaft,engineIs connected to the transmission, and thus to the drive shaft, the elements connected after the input shaft areengineIt will be dragged by the rotation of and will decelerate.
[0014]
  Here, in the present invention, the control means further includes the control unit.Motor generator deviceSo that the output of the engine is higher than the output before the clutch is engaged.Motor generator deviceTo control. Therefore, as mentioned above, the rotational speed is low.engineThe occurrence of a situation where the elements connected after the input shaft are decelerated by connectingMotor generator deviceThis assistance can be avoided in advance.
[0015]
  Thus, according to the present invention,engineEven if the rotational speed is still relatively low, since it is connected to the transmission and the drive shaft via the clutch, time is not wasted as in the prior art. In this case,Motor generator deviceAppropriate assistance from the vehicle is expected, so that the user does not feel uncomfortable such as a feeling of deceleration.In the present invention, in particular, in addition to the above-described effects, even if the start of the engine using the starter motor fails, the clutch is already in an engaged state. Can be maintained. Therefore, it is not necessary to try restarting the engine using the starter motor as in the prior art. As described above, according to the present invention, the necessity of executing the engine start again using the starter motor is greatly reduced, so that there is hardly any sense of incongruity such as vibration due to this. Furthermore, according to the present invention, when starting the engine, there is no need to carry out the control of increasing the fuel injection amount so much that there is a fear of the failure, so there is no possibility that the fuel consumption will be deteriorated or that the blow-up will occur. There is also no risk of worsening emissions from the engine.
[0016]
  In one aspect of the power output apparatus of the present invention, the control means includes:When engaging the clutch,According to the difference between the rotational speed of the engine and the rotational speed of the input shaft,Motor generator deviceTo increase the output ofMotor generator deviceTo control.
[0017]
  According to this aspect,Motor generator deviceOutput control ofengineThe degree of deceleration shock that would have occurred based on the difference between the number of rotations and the number of rotations of the input shaft, in other words, if the control of this aspect was not performed Will be done according toMotor generator deviceThe above-described assist can be more suitably implemented.
[0018]
  Note that “depending on” specifically refers to, for example, “from the rotational speed of the input shaft.engineThis means that the value is proportional to the value obtained by subtracting the number of rotations of "."
[0019]
  In this aspect, the control means includes the clutch.Increases torque capacityAfter the time point, the motor generator device may be controlled to reduce the output of the motor generator device.
[0020]
  According to such a configuration, the assist by the motor generator device can be more suitably performed. This is because even if the output of the motor generator device is reduced, the clutchIncreases torque capacityFrom that point on, it is possible to increase the output from the engine to meet this, and by doing so, the balance of the force applied to the drive shaft from both the engine and the motor generator device can be balanced. It is because it can take better. Furthermore, in this aspect, since the output of the motor generator device is reduced, waste of power consumption can be avoided.
[0025]
In another aspect of the power output apparatus of the present invention, when the clutch is engaged, the control unit controls the clutch so that the half-clutch state of the clutch passes for a certain period.
[0026]
  According to this aspect,engineIn the engagement of the clutch that is performed in a state where the rotational speed is lower than the rotational speed of the input shaft, a half-clutch state is realized for a certain period. Therefore, first, a series of operations can be smoothly executed despite the clutch engagement having a difference in the rotational speed as described above. Moreover, according to maintaining the half-clutch state for a predetermined period,Motor generator deviceIt is possible to suppress the degree of deceleration shock that would have occurred if there was no assist due to. In this respect, in the present invention,Motor generator deviceSince the occurrence of deceleration shock itself is not scheduled, but the degree is suppressed by the half-clutch state as described above,Motor generator deviceThe degree of assistance by can be estimated small. Therefore, according to this aspect, power consumption can be suppressed.
[0027]
  In another aspect of the power output apparatus of the present invention, a flywheel interposed between the engine and the clutch is further provided, and the control means includes the clutchIncreases torque capacityAfter the time point, after the engine speed exceeds the input shaft speed, the motor generator device is operated for a certain period of time.
[0028]
  According to this aspect, even after the clutch is completely engaged,Motor generator deviceIs for a certain periodWorking. With thisengineFrom the relationship with the flywheel provided between the clutch and the clutch, according to this aspect, the following operational effects can be obtained.
[0029]
  That is, the flywheel is provided, for example, around a crankshaft extending from the engine and rotatable with the rotation of the crankshaft. For example, the flywheel receives the power of the starter motor and transmits it to the crankshaft. . By the way, since such a flywheel generally has a relatively large radius, the power generated by the rotation of the engine generates an inertial force on the flywheel (inertia torque). By generating such inertial force,engineIt is conceivable that a situation occurs in which the rotation of the input shaft or the rotation of the input shaft is dragged by the rotation of the flywheel.
[0030]
  However, according to this aspect, even after the clutch is engaged.Motor generator deviceIs for a certain periodOperateFrom thatOf motor generator equipmentThe output can be used for absorption of inertia torque as described above. Therefore, according to this aspect,Motor generator deviceFrom driving byengineThe transition to it can be made more smoothly.
[0031]
  In this aspectThe control means is the time when the rotational speed of the engine exceeds the rotational speed of the input shaft or fromSaidA certain period of timelaterStop the motor generator deviceMay.
[0032]
  If configured in this wayThe control means performs the control for the motor generator device as described above, which is performed when the rotational power is transmitted from the engine in a stopped state to the drive shaft, for a predetermined period. Therefore, according to this aspect, it is possible to suitably perform a transition from an initial state where the drive shaft is driven only by the motor generator device to a state where the drive shaft is driven only by the engine. That is, it can be said that the “motor travel mode” is shifted to the “engine travel mode”.
[0033]
  In addition, in order to absorb the amount of inertia torque of the flywheel during the “certain period” in this aspect,Motor generator deviceOf course, the above "fixed period" is to be maintained. However, the “predetermined period” referred to in this embodiment can be set longer or shorter than the “determined period” for absorbing the inertia torque in some cases.
[0036]
In order to solve the above problems, a vehicle according to the present invention includes the power output device according to the present invention (including various aspects thereof), a vehicle main body on which the power output device is mounted, and the vehicle main body. And a wheel driven by a driving force output through the drive shaft.
[0037]
  Since the vehicle of the present invention comprises the power output device of the present invention, for example,Motor generator deviceFrom the driving mode byengineAt the time of switching to the travel mode by, wasteful time is not generated and the user does not feel uncomfortable such as vibration.
[0038]
Such an operation and other advantages of the present invention will become apparent from the embodiments described below.
[0039]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0040]
(Direct injection gasoline engine)
FIG. 1 is a diagram showing a configuration example of an engine 150 and its peripheral devices constituting a power output apparatus according to an embodiment of the present invention.
[0041]
As shown in FIG. 1, the engine 150 is a so-called direct injection gasoline engine that directly injects fuel into the fuel chamber. The engine 150 is provided with a cylinder block (not shown), a cylinder arranged inside the cylinder block, and a piston arranged so as to be slidable inside the cylinder.
[0042]
A crankshaft not shown in FIG. 1 is connected to the piston, and a flywheel is connected to the crankshaft (refer to reference numerals “151” and “FW” in FIG. 2, respectively)). A ring gear is provided on the outer periphery of the flywheel, and a pinion gear attached to the starter motor SM is engaged with the ring gear as shown in FIG. When the engine 150 is normally started, the power generated by the rotation of the starter motor SM is transmitted to the flywheel FW and the crankshaft 151 via the pinion gear and the ring gear, so that the engine 150 It will be cranked. 1 is connected to the crankshaft of engine 150, which will be described in detail later with reference to FIG.
[0043]
A combustion chamber 20 is formed in the space inside the cylinder and facing the top surface of the piston. In the combustion chamber 20, the injection port of the fuel injection valve 22 is exposed. During operation of the engine 150, fuel is pumped to the fuel injection valve 22 from a fuel pump (not shown). The combustion chamber 20 is provided with an ignition plug (not shown). When this ignition plug is ignited, an explosion occurs in the combustion chamber 20 and power is transmitted to the piston in the cylinder.
[0044]
In addition to the above, an exhaust manifold 30 communicates with the combustion chamber 20 via an exhaust valve (not shown). An exhaust pipe 31 is connected to the exhaust manifold 30 via a turbocharger 39. Among these, an exhaust purification device 35 made of, for example, a PM (exhaust particulate) filter or the like is provided in the middle of the exhaust pipe 31. The PM filter is a seamless tubular filter (liquid microfiltration filter) obtained by sintering stainless steel powder. The exhaust gas purification device 35 is provided with a temperature sensor 35T.
[0045]
On the other hand, each branch pipe of the intake manifold 32 communicates with the combustion chamber 20 via an intake valve (not shown). An intake pipe 33 is connected to the intake manifold 32 via an intercooler 39C. Among these, in the intake manifold 32, a throttle valve 32V is disposed.
[0046]
As devices related to both the exhaust system and the intake system, the engine 150 is provided with a turbocharger 39 and an exhaust gas recirculation (EGR) device 38.
[0047]
First, the turbocharger 39 includes, for example, a turbine and a compressor (both not shown). When the turbine is rotated by the energy of exhaust gas flowing in the exhaust manifold 30, the compressor transmits the power of the turbine to the shaft. To receive through. As a result, the air in the intake pipe 33 can be compressed and supplied to the combustion chamber 20 side. That is, the turbocharger 39 has a function of controlling the intake air amount with respect to the combustion chamber 20. Incidentally, an intercooler 39C is provided between the turbocharger 39 and the throttle valve 32V in the air intake direction of the intake pipe 33. The intercooler 39C is compressed by the turbocharger 39 and the temperature rises. For cooling the air. The turbocharger 39 may be a so-called variable displacement turbocharger that can control the discharge amount corresponding to the rotation speed of the compressor.
[0048]
On the other hand, the exhaust gas recirculation device 38 is provided in the middle of the pipe 38 connecting the exhaust manifold 30 and the intake manifold 32, and controls the flow rate of the gas returned from the exhaust manifold 30 to the intake manifold 32. EGR valve 38V. Thereby, a part of the gas discharged from the combustion chamber 20 to the exhaust manifold 30 can be returned to the intake system. According to this, the combustion temperature in the combustion chamber 20 decreases, and generation of nitrogen oxides and generation of exhaust particulates due to an increase in the intake air amount can be suppressed.
[0049]
Various mechanical elements including the engine 150 as described above are controlled by the control device 170. The control device 170 is a one-chip microcomputer having a CPU, a ROM, a RAM, and the like inside, and the CPU executes control of the fuel injection amount, the rotational speed, and the like of the engine 150 according to a program recorded in the ROM. Although illustration is omitted as appropriate, various sensors that indicate the operating state of the engine 150 are connected to the controller 170 in order to enable these controls.
[0050]
Specifically, it is as follows. For example, among the above elements, the throttle valve 32V is connected to a throttle motor (not shown), and the throttle motor is connected to the control device 170 and is under its control. Thereby, the throttle motor changes the opening degree of the throttle valve 32 </ b> V according to the control signal supplied from the control device 170. A throttle opening sensor (not shown) may be provided in the vicinity of the throttle valve 32V, and an electric signal corresponding to the opening of the throttle valve 32V generated by the sensor may be output to the control device 170. . The fuel injection valve 22 and the fuel pump are also connected to and under control of the control device 170. Thereby, the fuel pump pressure-feeds the fuel to the fuel injection valve 22 side according to the control signal supplied from the control device 170. The fuel injection valve 22 injects fuel into the combustion chamber 20 in accordance with a control signal supplied from the control device 170.
[0051]
In addition to the above, the turbocharger 39, the exhaust gas recirculation device 38, and the like are also connected to the control device 170, and under the control, the supercharging pressure, the recirculation exhaust gas amount, and the like can be appropriately adjusted. Yes.
[0052]
On the other hand, in addition to the various mechanical elements described above, an ignition switch 76 (hereinafter referred to as “IG switch 76”) is connected to the control device 170. Control device 170 detects the on / off state of IG switch 76 based on the output signal of IG switch 76. When the IG switch 76 is changed from the on state to the off state, the fuel injection by the fuel injection valve 22 is stopped, and the operation of the engine 150 is stopped. Further, an accelerator opening sensor 80 provided in the vicinity of the accelerator pedal 78 is connected to the control device 170. The accelerator opening sensor 80 outputs an electric signal corresponding to the depression amount of the accelerator pedal 78 to the control device 170.
[0053]
(Transmission device)
FIG. 2 is a diagram illustrating a configuration example of the transmission 160 illustrated in FIG. 1. In FIG. 2, the engine 150 is connected to a crankshaft 151 via a flywheel FW. A starter motor SM is connected to the flywheel FW via a pinion gear. The starter motor SM is mainly used when the engine 150 is started.
[0054]
The crankshaft 151 is connected to the input shaft 152 through the clutch C. The input shaft 152 is provided with input gears 1IN to 5IN (hereinafter referred to as “first-speed input gear 1IN”, etc.) for each speed from the first speed to the fifth speed around the axis, and the reverse gear. An input gear RIN is provided. Among these, the 3rd speed input gear 3IN, the 4th speed input gear 4IN and the 5th speed input gear 5IN are provided so as to be able to rotate relatively freely in relation to the input shaft 152. Further, a sleeve S1 is provided between the third speed input gear 3IN and the fourth speed input gear 4IN, and a sleeve S2 is provided corresponding to the fifth speed input gear 5IN. The sleeve S1 can be connected to the input shaft 152 and the third-speed or fourth-speed input gear 3IN or 4IN by moving in either the left or right direction in the figure. Similarly to the sleeve S1, the sleeve S5 can also connect the fifth-speed input gear 4IN and the input shaft 152 by moving in the right direction in the figure. A synchronizer (not shown) is provided between each of the sleeves S1 and S2 and the 3rd to 5th input gears 3IN to 5IN that can be connected to the sleeves so that the meshing between them is performed smoothly. It has been.
[0055]
On the other hand, the output shaft 153 has output gears 1OUT to 5OUT and ROUT (hereinafter referred to as “first speed output gear 1OUT”) corresponding to the input gears 1IN to 5IN of the respective speeds with the shaft as a center. Etc.) are provided. Among these, the first-speed output gear 1OUT, the second-speed output gear 2OUT, and the third-speed output gear 3OUT are provided so as to be relatively free to rotate in relation to the output shaft 153. A sleeve S3 is provided between the first-speed output gear 1OUT and the second-speed output gear 2OUT, and a sleeve S4 is provided so as to correspond to the third-speed output gear 3OUT. Both the sleeves S3 and S4 perform substantially the same function as the sleeves S1 and S2. That is, the sleeve S3 is configured to be movable so as to connect the output shaft 153 and the first-speed output gear 1OUT or the second-speed output gear 2OUT, and the sleeve S4 is configured to move the output shaft 153 and the third-speed output gear 3OUT. It is comprised so that movement is possible so that it may connect. However, the sleeve S3 serves to connect the output shaft 153 and the reverse gear output gear ROUT between the first speed output gear 1OUT and the second speed output gear 2OUT in the middle of the figure, and the reverse gear input gear. Power transmission from the RIN to the output shaft 153 is enabled. In addition, between the sleeves S3 and S4, and the 1st to 3rd speed output gears 1OUT to 3OUT and the reverse speed output gear ROUT that can be connected to the sleeves S3 and S4, respectively, the meshing between the two is performed smoothly. A synchronization device (not shown) is provided.
[0056]
Furthermore, a motor generator MG is connected to the third speed output gear 3OUT via a gear MGG. A battery V is connected to the motor generator MG. As a result, the motor generator MG supplied with power from the battery V functions as an electric motor so that power is transmitted to the output shaft 153 via, for example, the gear MGG, the third-speed output gear 3OUT, and the sleeve S4. (Powering operation). On the other hand, when the motor generator MG is rotated in the reverse order to the force received from the wheels TF1 and TF2, etc., the motor generator MG functions as a generator so that the battery V is charged. (Regenerative operation).
[0057]
A differential gear (hereinafter abbreviated as “DEF”) 154 is provided at one end of the output shaft 153 having such a configuration, and the DEF 154 is connected to a wheel not shown in FIG.
[0058]
The transmission 160 having the above configuration typically operates as follows. The operation of the transmission device 160 is performed by the control device 170 shown in FIG.
[0059]
Now, for example, the operation of the transmission 160 at the time of shifting from the first speed to the second speed using the engine 150 as a power source will be described. First, in the first speed traveling stage, the sleeve S3 moves rightward in the drawing so as to connect the first speed output gear 1OUT to the output shaft 153. On the other hand, the remaining sleeves S3 to S5 are all in a neutral state, so that power is not transmitted from the 2nd to 5th input gears 2IN to 5IN to the output shaft 153. As a result, the output from the engine 150 is transmitted to the DEF 154 via the clutch C via the input shaft 152, the first speed input gear 1IN, the first speed output gear 1OUT, the sleeve S1 and the output shaft 153.
[0060]
Subsequently, when shifting from this state to the second speed, the clutch C is once disconnected, and then the sleeve S3 is connected to the first speed output gear 1OUT to the second speed output gear 2OUT. Change to state. Thereafter, when the clutch C is engaged again, the output from the engine 150 is transmitted via the clutch C via the input shaft 152, the second speed input gear 2IN, the high speed output gear 2OUT, the sleeve S1 and the output shaft 153. Is transmitted to DEF 154.
[0061]
Even after the remaining third speed travel, the same speed change action is realized by appropriately moving the sleeves S1 to S4. Note that the shifting operation as described above is governed by the control device 170 shown in FIG. In this case, when the control device 170 actually performs the shift operation, there are both a case where it is based on a user command (semi-auto type) and a case where it is automatically performed (full-auto type). In the embodiment, the latter case is assumed.
[0062]
(vehicle)
A power output apparatus including the engine 150, the transmission 160, or the like as described above constitutes a part of the four-wheeled vehicle MV as shown in FIG. 3, in addition to the engine 150, the transmission 160, the motor generator MG and the like shown in FIG. 1, the four-wheeled vehicle MV is attached to the vehicle main body MVS, the vehicle main body MVS, and connected to the DEF 154. Wheels TF1 and TF2 and wheels TR1 and TR2 and the like. Of these, the wheels TF1 and TF2 are driven by the driving force output via the output shaft 153 and DEF154.
[0063]
(Control related to clutch when switching modes)
In the following description, the control device 170 constituting the control means according to the present invention controls the travel mode, particularly from the “motor travel mode” in which the output shaft 153 is driven only by the motor generator MG. The control performed at the time of switching to the “engine running mode” will be described with reference to FIGS. 4 and 5. FIG. 4 is a flow chart showing the flow of the control process, and FIG. 5 is a flow chart of the process according to the flow chart of FIG. 4 is a timing chart showing how output torques of motor generator MG and engine 150 change.
[0064]
In FIG. 4, first, in the initial stage, the power output apparatus is in a motor travel mode in which the output shaft 153 is driven only by the motor generator MG (step S1). That is, in FIG. 2, for example, the sleeve S4 is moving toward the third speed output gear 3OUT, and the output of the motor generator MG is sent to the output shaft 153 via the sleeve S4 and the third speed output gear 3OUT. It has come to be communicated. Incidentally, such a motor travel mode is employed, for example, when the vehicle travels at a low speed as shown in FIG.
[0065]
In FIG. 4, in such an initial stage, control device 170 checks the time point of transition to the engine travel mode (from step S2 to step S3 and subsequent steps). Specifically, for example, when the user depresses the accelerator pedal 78, there is an output increase request to the power output device, and when this is above a certain level, traveling by the conventional motor generator MG is performed. Since the torque shortage occurs only with the control unit 170, the control device 170 determines to shift to the “engine running mode” in which the output shaft 153 is driven by the engine 150. In addition, the transition from the motor travel mode to the engine travel mode can be performed due to various circumstances.
[0066]
If the transition to the engine running mode is determined, the engine 150 is then started (step S3). This is realized by starting the starter motor SM in FIG. 2, cranking the engine 150, injecting fuel into the combustion chamber 20 of the engine 150, and further igniting a spark plug. Will be. In FIG. 5, the time from t1 to t2 corresponds to the time for performing the above processing. Incidentally, it means that cranking by the starter motor SM is performed at time t1, and fuel injection and ignition are performed at time t2. After the time t2, it is shown that the rotational speed of the engine 150 (hereinafter sometimes referred to as “Ne”) gradually increases. In FIG. 5, the rotational speed of the input shaft 152 (hereinafter also referred to as “Ni”) is indicated by a broken line along with the graph of the engine rotational speed. Further, the decision to shift to the engine travel mode in step S2 in FIG. 4 is made before time t1, but at this time, the output shaft 153 is still driven only by the motor generator MG. As described above, the fact that “motor travel” is shown in FIG. 5 until time t3 in spite of the transition to the engine travel mode as the “mode” represents such a purpose. .
[0067]
After starting the engine 150 in this way, the control device 170 next checks the current rotational speed Ni of the input shaft 152 and the rotational speed Ne of the engine 150 and calculates the difference ΔN = Ni−Ne. (Step S4). However, the calculation of ΔN is not necessarily performed in such a way as to divide the execution time, and may be performed at any time as described later.
[0068]
Subsequently, the control device 170 starts the engagement of the clutch C (step S5). In this case, the clutch C is engaged in a state where the engine speed Ne is lower than the speed Ni of the input shaft 152, that is, in a state immediately after the engine 150 is started. FIG. 5 shows that the engagement of the clutch C is started at the time t3 in the state, that is, Ne <Ni. Further, in FIG. 5, it is shown that the torque capacity of the clutch C increases, and the output of the engine 150 is transmitted to the input shaft 152 so as to match the torque capacity of the clutch C. The graph is shown to rise.
[0069]
However, when the engagement of the clutch C is started in such a state of Ni> Ne, various elements connected after the input shaft 152 are dragged by the rotation of the engine 150 and decelerated. As a result, the user of the power output apparatus is given an uncomfortable feeling such as a feeling of deceleration.
[0070]
Therefore, in the present embodiment, in addition to starting the engagement of the clutch C in a state of Ni> Ne, the motor generator MG assists so as to prevent the deceleration. Specifically, the “assist” in this case is performed according to a graph drawn as “basic motor torque” and “assist torque” shown in FIG.
[0071]
In FIG. 5, the net torque output from the motor generator MG is represented by the sum of the basic motor torque graph (dashed line in the figure) and the assist torque graph (dashed line in the figure). Medium thick solid line). Here, the basic motor torque represents a basic torque output by the motor generator MG. This basic motor torque coincides with the net output torque of motor generator MG before time t3, that is, before the start of engagement of clutch C. On the other hand, the assist torque is torque that is specially added in the present embodiment in order to prevent the deceleration.
[0072]
Then, the control device 170 according to the present embodiment first increases the output of the motor generator MG as shown in the assist torque graph at time t3 almost in time with the start of engagement of the clutch C. (Step S6). That is, in this state, the output of engine 150 is transmitted to output shaft 153 by the engagement of clutch C, and at the same time, the output of motor generator MG is also transmitted.
[0073]
Incidentally, the degree of the steep increase of the assist torque at the time point t3 is the viewpoint of how much the output of the motor generator MG is suitable for sufficiently rotating the flywheel FW having a relatively large radius (see FIG. 2). Is preferably determined from
[0074]
In this case, the degree of increase in the output of motor generator MG is determined according to ΔN calculated in step S4 in FIG. 4, or more specifically, determined to be proportional to ΔN. Good. In this way, it is possible to perform appropriate assist that is commensurate with the degree of deceleration shock that would have occurred when there was no assist of the motor generator MG. Moreover, according to this, since there is no possibility that the motor generator MG consumes more power than necessary, energy saving can be achieved.
[0075]
As described above, when the assist at the time t3 is completed, the controller 170 continues to reduce both the basic motor torque and the assist torque related to the motor generator MG as shown in FIG. The output is controlled so as to reduce the net torque of the generator MG. This is a measure that keeps pace with the gradual increase in the engine torque obtained from the engine 150. As described above, it is preferable that the degree of the assist after the start of the assist by the motor generator MG takes into account changes in the engine speed Ne of the engine 150 or the engine torque with time (step S8). In FIG. 5, as time advances, the input from the engine 150 to the input shaft 152 gradually increases, so the degree of increase in the output of the motor generator MG or the degree of assist is gradually reduced. It is preferable. Therefore, in the above description, ΔN = Ni−Ne is calculated in step S4 of FIG. 4. However, this calculation is executed as needed or appropriately as long as the motor generator MG needs assistance. (If it says in FIG. 4, it can be considered that it is implemented together with the process of step S8.). It is preferable that the degree of increase in the output of motor generator MG or the degree of assist is determined each time or based on ΔN obtained as needed.
[0076]
By the way, in the present embodiment, in particular, during the execution of the assist as described above, the control device 170 keeps the clutch C in a half-clutch state for a predetermined period (in FIG. 5, it is represented by the symbol P). , The torque capacity takes a constant value). According to this, the following effects can be obtained. That is, first, a series of operations can be smoothly executed despite the clutch engagement having the difference in rotational speed as described above. Further, by maintaining the half-clutch state for a predetermined period, the degree of deceleration shock that would have occurred if there was no assist by the motor generator MG would be suppressed. The degree of assist by the generator MG can be estimated small. Therefore, power consumption in the motor generator MG can be suppressed.
[0077]
The assistance by the motor generator MG as described above is basically performed until the rotational speed Ne of the engine 150 exceeds the rotational speed Ni of the input shaft 152 (step S7). That is, after step S7 in FIG. 4, as long as Ne ≦ Ni, the assist by the motor generator MG as described above is performed (a loop in which steps S7 and S8 are repeated). Exit (from step S7 to step S9). In FIG. 5, this time point Ne> Ni is shown as time t4.
[0078]
Then, after Ne> Ni is established and the process exits the loop, in the present embodiment, the assist by the motor generator MG is continued for a while after this (step S9). The assist torque in this case takes a negative value as shown after time t4 in FIG. According to the assist by the motor generator MG that is continued even after Ne> Ni, the following operational effects can be obtained. That is, the engine 150 according to the present embodiment is provided with a flywheel FW having a relatively large radius as shown in FIG. 2, and when the engine 150 rotates, the flywheel FW has an inertial force. To be given (inertia torque). The presence of such inertia torque is not preferable in order to stabilize the entire system. However, in the present embodiment, even after Ne> Ni, since the negative assist torque as described above is applied, the inertia torque can be absorbed.
[0079]
FIG. 5 shows how inertia torque is absorbed. First, the graph of the engine torque or the graph of the rotational speed Ne of the engine 150 shows that the engine torque or the rotational speed Ne has increased more than a certain amount after the time t4. On the other hand, before the time t4, the motor generator MG is subjected to the output control according to ΔN as described above, so that its output is monotonously decreased. At the time t4, the “assist torque” is It is “0”. However, in this embodiment, the assist by the motor generator MG is continued even after the time t4. This is a negative assist as described above. By executing such negative assist, the inertia torque is absorbed. Thereby, in this embodiment, the transition from the motor travel mode to the engine travel mode can be performed extremely smoothly.
[0080]
As described above, after Ne> Ni, the assist of the motor generator MG is continued for a certain period. At the time when the above-described object is achieved, the control device 170 stops the motor generator MG (step S1). S10). In FIG. 5, the physical stop point of this motor generator MG is shown by time t5. In this case, the rotational speed Ni of the input shaft 152 takes substantially the same value as the rotational speed Ne of the engine 150.
[0081]
In addition to or after the above process, the control device 170 causes the clutch C in the half-clutch state to be completely engaged (step S11). As a result, the “torque capacity” of the clutch C increases as shown in FIG. When the torque capacity takes a constant value, it means that the transition from the motor travel mode to the engine travel mode is completely completed in the power output apparatus according to this embodiment.
[0082]
In the power output apparatus of the present embodiment that performs the control as described above, the following operational effects can be obtained. That is, first, since the engagement of the clutch C is already executed when the rotational speed Ne of the engine 150 is lower than the rotational speed Ni of the input shaft 153, Ne> Ni as in the conventional case. Compared with refraining from engaging the clutch until it becomes, it can earn time corresponding to. That is, useless time is not consumed.
[0083]
Second, when Ne <Ni, the clutch C is engaged so that a deceleration shock may occur. In the present embodiment, at the same time as the clutch C is engaged, the motor generator Since the control for increasing the output of the MG is executed, the deceleration shock can be prevented from being generated. Further, the degree of the output increase or the degree of assist by the motor generator MG is performed according to ΔN = Ni−Ne, and thus the assist is appropriately executed.
[0084]
Thirdly, in this embodiment, even if the engine start in step S3 in FIG. 4 fails, there is no need to attempt to restart the engine 150 using the starter motor SM. This is because the clutch C is brought into the engaged state soon after the engine 150 is started, so that the rotational speed of the engine 150 can be maintained by the inertial force of the output shaft 153. As described above, according to the present embodiment, the necessity of executing the engine 150 restart using the starter motor SM is reduced, so that there is almost no sense of discomfort such as vibration due to this. . Furthermore, according to the present embodiment, when starting the engine 150, it is not necessary to carry out the control of increasing the fuel injection amount so much that there is a fear of the failure. In addition, there is no possibility of deteriorating emissions from the engine 150.
[0085]
The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. The control method and the vehicle are also included in the technical scope of the present invention.
[0086]
【The invention's effect】
As described above, according to the power output apparatus of the present invention, even when the rotational speed of the first drive source is lower than the rotational speed of the input shaft, the first drive source is connected to the clutch. Since the transmission and the drive shaft are connected to each other, time is not wasted unlike the conventional case. In this case, since appropriate assistance from the second drive source is expected, the user does not feel uncomfortable such as a feeling of deceleration.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration example of an engine and its peripheral devices constituting a power output apparatus according to an embodiment of the present invention.
2 is a diagram showing a configuration example of a transmission shown in FIG.
FIG. 3 is a diagram illustrating an example of a vehicle according to an embodiment of the present invention.
FIG. 4 is a flowchart showing a flow of control processing executed when switching from the motor travel mode to the engine travel mode, and in particular, when the engine speed is lower than the input shaft speed, the clutch is engaged. It shows what will start.
5 is a timing chart showing how the engine speed, the torque capacity of the clutch, or the output torque of the motor generator MG and the engine changes in the processing flow according to the flowchart of FIG. 4; .
[Explanation of symbols]
150 ... Engine
153 ... Output shaft
160 ... transmission
170 ... Control means
C ... Clutch
22 ... Fuel injection valve
35. Exhaust purification device
MG ... motor generator

Claims (7)

An engine that outputs rotational power;
A starter motor connected to the crankshaft of the engine and helping to start the engine ;
A transmission having an input shaft connected to or disconnected from the crankshaft via a clutch and directly connected to the clutch ;
A drive shaft to which the rotational power is transmitted via the transmission,
A motor generator device connected to the transmission so as to drive the drive shaft ;
In a case where the previous SL drive shaft is driven by the motor-generator device, in time of starting the engine in a state of being stopped by the starter motor, the starting of the engine was started by the starter motor, the engine Before the rotational speed of the input shaft becomes higher than the rotational speed of the input shaft, the clutch is controlled to engage the clutch, and the output of the motor generator device is set higher than the output before the clutch is engaged A power output device comprising: control means for controlling the motor generator device so as to be raised. The control means includes
When the clutch is engaged, the motor generator device is controlled so as to increase the output of the motor generator device in accordance with the difference between the engine speed and the drive shaft speed. The power output device according to claim 1. The control means includes
3. The power output apparatus according to claim 2, wherein the motor generator apparatus is controlled to decrease the output of the motor generator apparatus after the time point when the torque capacity of the clutch increases . The control means includes
4. The power output apparatus according to claim 1, wherein when the clutch is engaged, the clutch is controlled so that a half-clutch state of the clutch is allowed to pass for a certain period. 5. A flywheel interposed between the engine and the clutch;
The control means includes
The motor generator device is operated for a certain period after the engine speed exceeds the input shaft speed after the torque capacity of the clutch increases . The power output device according to one item. The control means includes
Power output apparatus according to claim 5 in which the rotational speed of the engine after a time, or it than the certain period exceeds the rotational speed of the input shaft, characterized by stopping the motor-generator device. The power output apparatus according to any one of claims 1 to 6,
A vehicle body on which the power output device is mounted;
A vehicle comprising: a wheel attached to the vehicle main body and driven by a driving force output through the drive shaft.

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