JP2012166575A - Vehicle drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable shift control to an optimum driving gear position corresponding to the required driving force in high response at pushing start of the engine at motor traveling.SOLUTION: When performing push start of the engine, a control device selects a shift position where the engine rotation speed in performing push start becomes more than a necessary rotation speed that the engine speed set beforehand as a shift position to be used for the push start, and controls to perform push start of the engine using the selected shift position (SR1). When performing the push start of the engine, the control device obtains the predicted target driving force predicted after the predetermined time of the engine start based on a present target driving force and decides the predicted driving gear position based on the predicted target driving force (SR2). Control is carried out to achieve the decided prediction drive gear position, as a shift position for running the engine travel after the push start of the engine (SR3).

Description

  The present invention relates to a drive device used for a vehicle (so-called hybrid vehicle) including an internal combustion engine and an electric motor as a prime mover, and more particularly, to a state where the engine is started from a single motor traveling state and travels using the internal combustion engine. The present invention relates to an improvement in shift control when switching.

  2. Description of the Related Art In recent years, a transmission for a vehicle has an input shaft (hereinafter referred to as a first input shaft) of a first transmission mechanism configured with an odd number of shift stages in order to eliminate the interruption of transmission of mechanical power during a shift. ) And the output shaft of the internal combustion engine (hereinafter referred to as the engine output shaft or the engine output shaft), and the input shaft (hereinafter referred to as the input shaft of the second transmission mechanism) composed of an even number of shift stages. There is known a so-called dual clutch type transmission that includes a second clutch capable of engaging an engine output shaft and a second clutch capable of engaging with the engine output shaft and performing a shift by alternately switching these two clutches. Yes. For example, when shifting from an odd-numbered gear to an even-numbered gear, the dual-clutch transmission has meshed an even-numbered gear pair in advance and disengages the first clutch that transmits mechanical power to the odd-numbered gear. At the same time, by disengaging the second clutch that transmits the mechanical power to the even stages, the transmission of power during the shift is suppressed.

  Patent Document 1 below shows a hybrid type vehicle drive device that includes two transmission mechanisms as described above, and further includes an electric motor that engages with the input shaft of one transmission mechanism. . There are three forms of power supply in such a hybrid type vehicle drive device: engine traveling alone, motor traveling alone, and hybrid traveling using a combination of the engine and motor. Which power supply mode should be adopted is appropriately controlled according to the driving state of the vehicle.

  By the way, since the engine is stopped in the motor independent traveling state, it is necessary to start the engine when shifting from motor independent traveling to engine traveling during vehicle traveling. For this purpose, the engine is pushed and started (cranking) using the rotation of the motor used for running the vehicle, and after the engine is started, the engine is run by setting an appropriate gear position. For example, assuming that the motor is engaged with the input shaft of the first transmission mechanism, the engine travels when the motor is traveling alone using the gear position (odd gear position) of the first transmission mechanism. In order to shift, while maintaining the selection of the shift speed of the first transmission mechanism (odd shift speed) (connection to the shift output shaft), an appropriate one of the shift speeds of the second speed change mechanism (even shift speed) is selected. The gear stage is selected and the second clutch is engaged, and the power of the motor is transmitted to the engine output shaft of the engine via the selected gear stage and the second clutch of the second transmission mechanism. Thus, the engine is pushed and started (cranking). In this case, as the gear stage used for pushing start, the engine rotational speed when the gear stage is connected to the engine output shaft is equal to or higher than a preset required rotational speed (rotational speed necessary for pushing start) and The gear position is selected so as to be the lowest. As a result, pressing is performed at a high gear (speed) at which the engine can be instantly started, and the energy loss of the motor during pressing is reduced.

Japanese Patent No. 4285571

  In such a conventional push start control of the engine, the target drive gear stage (target shift stage) after the engine start is determined according to a normal shift stage selection criterion, and the shift control is performed. Therefore, there is a problem that the response to reaching the final driving force is not good. The reason for this is that the engine pushing start from the motor traveling alone is often carried out while the accelerator pedal is depressed, and the accelerator pedal opening at the time of pushing start or when the engine ignition is completed (that is, the accelerator pedal opening during the depression) If the target drive gear stage (target gear stage) for driving the engine is determined according to), it becomes necessary to immediately change the drive gear stage (shift stage) by further depression of the accelerator pedal opening. It is. As a result, the number of times the drive gear stage (shift stage) is changed during the pushing start control is increased, and the response to reaching the final driving force is deteriorated. For example, when the motor is traveling alone at the 3rd speed, the 4th speed is selected as the gear position for pushing start and the pushing start is performed, and the accelerator pedal opening at the time of pushing start or completion of the engine ignition (that is, during the depression) When the target drive gear stage (target shift stage) for engine driving determined according to the accelerator pedal opening) is the third speed, the gear is temporarily shifted to the determined third speed. In response to the further stepping in, the gear-down control mode in which the gear shift to the second speed is finally made by easily giving a kick-down instruction to the second speed.

  The present invention has been made in view of the above-described points. When the engine is started from the motor-only traveling state and switched to the state of traveling using the engine, the optimum driving gear stage according to the required driving force is increased. It is an object of the present invention to provide a vehicle drive device that can perform speed change control in response.

  A vehicle drive device according to the present invention is used in a vehicle including an internal combustion engine (2) and a motor (3) as a prime mover, and shifts mechanical power from the internal combustion engine and the motor to drive wheels. A vehicle drive device capable of transmitting to an engaged vehicle propulsion shaft, wherein mechanical power from an engine output shaft and the motor is received by a first input shaft (IMS), and any one of a plurality of shift stages The first speed change mechanism that can be shifted by the transmission propulsion shaft and mechanical power from the engine output shaft is received by the second input shaft (SS), and the speed is changed by any one of the plurality of speed stages. A second transmission mechanism capable of transmitting to the vehicle propulsion shaft, a first clutch (C1) capable of engaging the engine output shaft and the first input shaft, the engine output shaft and the second input shaft. A second clutch (C2) capable of engaging The control means (10) comprises control means (10) capable of controlling the selection of the shift speed in the first transmission mechanism and the second transmission mechanism and the engagement state of the first clutch and the second clutch. In addition, when the engine is pushed and started while the vehicle is running using only a motor as a prime mover, the engine speed at the time of pushing and starting is preset as a shift stage used for the pushing and starting. A first means (SR1) for controlling the engine to start pushing the engine using the selected gear, and a current speed when the engine is pushed to start is selected. Second means for obtaining a predicted target driving force predicted after a predetermined time of engine start based on the target driving force and determining a predicted driving gear stage based on the predicted target driving force And SR2), as the shift stage of the engine traveling after starting stormed of the engine, characterized in that it comprises a third means (SR3) which controls so as to achieve the predicted driving gear stage the determined. The numbers in parentheses above indicate the corresponding drawing reference numbers in the examples described later for reference.

  According to the present invention, when the engine is pushed and started, a predicted target driving force predicted after a predetermined time of engine starting is obtained based on the current target driving force, and the predicted driving gear stage is set based on the predicted target driving force. Control is performed so that the determined predicted drive gear stage is realized as a shift stage for engine travel after the engine is pushed and started. Thus, at the time of engine pushing start, since the predicted drive gear stage is determined based on the predicted target driving force predicted from the current target driving force, when the engine pushing start is performed during the depression of the accelerator pedal, It is possible to determine the predicted drive gear stage that reflects the driver's final required drive force as accurately as possible, and when switching from the motor independent running state to the state running using the engine Therefore, it becomes possible to control the shift with high response to the optimum driving gear according to the required driving force.

  In one embodiment, the first means needs to be set in advance in the shift stage of the second transmission mechanism when using the first transmission mechanism in which the predicted drive gear stage is different from the current shift stage. A gear stage that is equal to or higher than the rotational speed is selected, and the second clutch having the selected gear stage is engaged and controlled to start pushing the engine, and the third means is during the pushing start of the engine. In addition, control may be performed so that the gear stage selected in the first transmission mechanism is switched to the predicted drive gear stage. In this way, a quick shift can be achieved by switching the shift stage selected in the first transmission mechanism to the predicted drive gear stage (for example, switching the synchro so that the predicted drive gear stage is selected) while the engine is pushed and started. Is possible.

  In one embodiment, the first means engages the first or second clutch having a gear selected for starting the engine and engages the engine, and the third means includes Further, during the pushing start of the engine, control may be performed so as to switch the shift speed selected in the first or second speed change mechanism having the predicted drive gear stage to the predicted drive gear stage. In this case as well, the gear stage selected in the first or second transmission mechanism having the predicted drive gear stage is switched to the predicted drive gear stage during the pushing start of the engine (for example, the predicted drive gear stage is selected). By changing the synchro to (1), quick shifting can be achieved.

  In one embodiment, the third means disengages the first or second clutch used to push the engine to achieve the determined predicted drive gear stage, and You may control to engage the said 1st or 2nd clutch corresponding to the said 1st or 2nd transmission mechanism with a drive gear stage. By such clutch switching, the speed change mechanism connected to the engine output shaft can be smoothly and quickly switched from the pushing start type to the engine running type. Stable shift control can be performed without being transmitted to the drive output shaft.

  In one embodiment, when the third means determines that the engine has undergone an initial explosion or complete explosion by the pushing to realize the determined predicted drive gear stage, the first means is used for the pushing. Alternatively, the engagement of the second clutch is once released, and then the first or second clutch corresponding to the first or second transmission mechanism that has selected the shift stage corresponding to the predicted drive gear stage is engaged. You may control. By such clutch switching, the speed change mechanism connected to the engine output shaft can be smoothly switched from the push start type to the engine running type, and the unstable behavior at the time of engine start is the drive output of the transmission. Stable shift control can be performed without being transmitted to the shaft.

  In one embodiment, the third means is used for the pushing when the gear stage used for the pushing start and the gear stage corresponding to the predicted drive gear stage are different gear stages of the second transmission mechanism. When the engagement of the second clutch is once released, the gear selected in the second speed change mechanism is switched to a gear corresponding to the predicted drive gear, and then the gear corresponding to the predicted drive gear Control may be performed so that the second clutch corresponding to the second transmission mechanism selected is engaged. Thus, when different gear stages of the same second speed change mechanism are used as the gear stage for pushing start and the drive gear stage for engine running, the engagement of the second clutch is once released at the end of pushing start, Sometimes, the shift stage selected in the second transmission mechanism is switched to a shift stage corresponding to the predicted drive gear stage (for example, the synchro is replaced), and then the second clutch is engaged again. A smooth and stable gear change can be performed from the gear to the engine gear.

  In one embodiment, the third means controls to switch the shift stage selected in the first or second transmission mechanism having the predicted drive gear stage to the predicted drive gear stage during the pushing start of the engine. The determined predicted drive gear stage may be realized by engaging the first or second clutch corresponding to the first or second transmission mechanism having the predicted drive gear stage after the engine is started. As a result, a quick shift is possible, and the engine can be moved when the engine rotation is stabilized.

  In one embodiment, when the predicted drive gear stage is a shift stage using the first transmission mechanism different from the current shift stage, the first means starts the engine in the shift stage of the second transmission mechanism. Selecting a shift speed that is greater than or equal to the possible number of rotations, and engaging the second clutch with the selected shift speed to perform pushing start of the engine, and the third means in the first speed change mechanism The determined predicted drive gear stage may be realized by switching the selected gear position to the predicted drive gear stage and simultaneously engaging the first clutch. As a result, a quick shift can be achieved, and the engine can be moved to the engine quickly.

The schematic connection block diagram of the vehicle in one Embodiment of this invention. The skeleton figure of the transmission shown in FIG. The conceptual diagram which shows the engagement relationship of each shaft of the transmission shown in FIG. The flowchart which shows the outline of the engine pushing start process performed by the electronic control unit shown in FIG. 5 is a flowchart showing an example of a predicted drive gear stage determination subroutine in FIG. 4. The figure for demonstrating an example of the prediction target driving force calculation method in the prediction target driving force calculation step in FIG. The time chart which shows the operation example of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  The vehicle drive device according to the present invention is applied to a vehicle driven by battery power and fuel, such as a hybrid vehicle. The control device (control means) included in the vehicle drive device according to the present invention is realized by, for example, an electronic control unit (ECU) 10 mounted on the vehicle to control the entire vehicle. In the following embodiments, the electronic control unit 10 will be described as controlling an engine and controlling a transmission, a battery, and an electric motor (motor).

  First, the configuration of the vehicle in the present embodiment will be described. FIG. 1 is a schematic connection configuration diagram of a vehicle according to an embodiment of the present invention. The vehicle 1 of the present embodiment is a so-called hybrid vehicle, and as shown in FIG. 1, an engine 2, a motor 3, motor control means 20 for controlling the motor 3, a battery 30, and a transmission 4. A differential mechanism 5, left and right drive shafts 6R and 6L, and left and right drive wheels 7R and 7L are provided. The rotational driving force of the engine 2 and the motor generator 3 is transmitted to the left and right drive wheels 7R, 7L via the transmission 4, the differential mechanism 5, and the drive shafts 6R, 6L.

  The vehicle 1 also includes an electronic control unit (ECU) 10 for controlling the engine 2, the motor 3, the transmission 4, the differential mechanism 5, the motor control means 20, and the battery 30, respectively. The electronic control unit 10 is not only configured as one unit, but includes, for example, an engine ECU for controlling the engine 2, a motor generator ECU for controlling the motor generator 3 and the motor generator control means 20, and a battery 30. A plurality of ECUs such as a battery ECU for controlling and an ATECU for controlling the transmission 4 may be included.

  The electronic control unit 10 performs control so that the motor alone travels (EV travel) using only the motor 3 as a power source according to various operating conditions, or performs the engine alone travel using only the engine 2 as a power source. Control is performed in such a way that the engine 2 and the motor 3 are used in combination as power sources. Further, the electronic control unit 10 performs shift control according to the accelerator pedal opening detected by the accelerator pedal opening detector 40 and other known operation parameters, and performs control necessary for other various operations. Do.

  The engine 2 is an internal combustion engine that generates driving force for running the vehicle 1 by mixing fuel with air and burning it. The motor 3 functions as a motor that generates a driving force for running the vehicle 1 using the electric energy of the battery 30 when the engine 2 and the motor 3 are collaboratively run or when the EV 3 is driven only by the motor 3. In addition, when the vehicle 1 decelerates, it also functions as a generator that generates electric power by regeneration of the motor 3. During regeneration of the motor 3, the battery 30 is charged with electric power (regenerative energy) generated by the motor 3.

  In the present embodiment, the engine 2, the motor 3, and the like are only required to have a known configuration, and are not a characteristic part of the present invention. Therefore, detailed description thereof is omitted.

  Next, the configuration of the transmission 4 according to the present embodiment will be described. FIG. 2 is a skeleton diagram of the transmission 4 shown in FIG. FIG. 3 is a conceptual diagram showing the engagement relationship of the shafts of the transmission 4 shown in FIG. The transmission 4 shown in FIG. 1 is a parallel shaft transmission of 7 forward speeds and 1 reverse speed, and is a dry twin clutch transmission (DCT: dual clutch transmission).

  The transmission 4 includes a crankshaft (not shown) forming an engine output shaft of the engine 2 and an inner main shaft IMS (first input shaft) connected to the motor 3 and an outer cylinder of the inner main shaft IMS. The outer main shaft OMS (second input shaft), the secondary shaft SS (second input shaft) parallel to the inner main shaft IMS, the idle shaft IDS, the reverse shaft RVS, and the counter that forms an output shaft parallel to these shafts A shaft CS is provided.

  Out of these shafts, the outer main shaft OMS is always engaged with the reverse shaft RVS and the secondary shaft SS via the idle shaft IDS, and the counter shaft CS is further always engaged with the differential mechanism 5 (not shown in FIG. 2). Be placed.

  Further, the transmission 4 includes a first clutch C1 for odd-numbered stages and a second clutch C2 for even-numbered stages. The first and second clutches C1 and C2 are dry clutches. The first clutch C1 is coupled to the inner main shaft IMS (first input shaft). The second clutch C2 is coupled to the outer main shaft OMS (a part of the second input shaft) and is connected to the reverse shaft RVS and the secondary shaft SS (first shaft) from the gear 48 fixed on the outer main shaft OMS via the idle shaft IDS. 2 part of the input shaft).

  A sun gear 71 of the planetary gear mechanism 70 is fixedly disposed at a predetermined position from the motor 3 of the inner main shaft IMS (first input shaft). Further, on the outer periphery of the inner main shaft IMS (first input shaft), the carrier 73 of the planetary gear mechanism 70 serving as the first speed drive gear, the third speed drive gear 43, and the seventh speed drive gear 47 are arranged in order from the left side in FIG. And the 5-speed drive gear 45 is arrange | positioned. The third speed drive gear 43, the seventh speed drive gear 47, and the fifth speed drive gear 45 are rotatable relative to the inner main shaft IMS, and the gear 43 is connected to the carrier 73 of the planetary gear mechanism 70. Further, on the inner main shaft IMS, a 3-7 speed synchromesh mechanism (selector mechanism) 81 is provided between the 3rd speed drive gear 43 and the 7th speed drive gear 47 so as to be slidable in the axial direction. Corresponding to the high-speed drive gear 45, a 5-speed synchromesh mechanism (selector mechanism) 82 is provided to be slidable in the axial direction. By sliding a synchromesh mechanism (selector mechanism) corresponding to a desired gear stage and inserting the gear stage, the gear stage is connected to the inner main shaft IMS (first input shaft). These gears and synchromesh mechanisms provided in association with the main shaft IMS (first input shaft) constitute a first transmission mechanism for realizing an odd number of shift stages. Each drive gear of the first speed change mechanism meshes with a corresponding driven gear provided on the countershaft CS to rotationally drive the countershaft CS.

  On the outer periphery of the secondary shaft SS (second input shaft), a second speed drive gear 42, a sixth speed drive gear 46, and a fourth speed drive gear 44 are relatively rotatably arranged in order from the left side in FIG. . Further, on the secondary shaft SS, a 2-6 speed synchromesh mechanism 83 is provided between the 2nd speed drive gear 42 and the 6th speed drive gear 46 so as to be slidable in the axial direction. Correspondingly, a 4-speed synchromesh mechanism (selector mechanism) 84 is provided to be slidable in the axial direction. Also in this case, the gear stage is connected to the secondary shaft SS (second input shaft) by sliding the synchromesh mechanism (selector mechanism) corresponding to the desired gear stage and inserting the gear stage. These gears and synchromesh mechanisms provided in association with the secondary shaft SS (second input shaft) constitute a second transmission mechanism for realizing an even number of shift stages. Each drive gear of the second speed change mechanism also meshes with a corresponding driven gear provided on the countershaft CS to rotate the countershaft CS. The gear 49 fixed to the secondary shaft SS is coupled to the idle shaft IDS, and is coupled from the idle shaft IDS to the second clutch C2 via the outer main shaft OMS.

  In the first speed change mechanism, selecting an arbitrary gear position means that the gear corresponding to the gear position is synchronized and the gear is connected to the inner main shaft IMS (first input shaft). Means. Further, in the first speed change mechanism, to realize a speed stage (or drive gear stage) for running the engine means that the speed stage (or drive gear stage) is selected as described above (with synchronization). This means that the corresponding first clutch C1 is engaged to connect the inner main shaft IMS (first input shaft) to the engine output shaft.

  Similarly, in the second speed change mechanism, when an arbitrary certain speed is selected, the gear corresponding to the speed is synchronized and the gear is connected to the secondary shaft SS (second input shaft). Means. Further, in this second speed change mechanism, to realize a speed stage (or drive gear stage) for running the engine means that the speed stage (or drive gear stage) is selected as described above (with synchronization). This means that the corresponding second clutch C2 is engaged to connect the secondary shaft SS (second input shaft) to the engine output shaft.

  A reverse drive gear 46 is disposed on the outer periphery of the reverse shaft RVS so as to be relatively rotatable. On the reverse shaft RVS, a reverse synchromesh mechanism 85 corresponding to the reverse drive gear 46 is slidable in the axial direction, and a gear 50 that engages with the idle shaft IDS is fixed. When traveling in reverse, the synchromesh mechanism 85 is synchronized and the second clutch C2 is engaged to transmit the rotation of the second clutch C2 to the reverse shaft RVS via the outer main shaft OMS and the idle shaft IDS. Then, the reverse drive gear 46 is rotated. The reverse drive gear 46 meshes with the gear 56 on the inner main shaft IMS, and when the reverse drive gear 46 rotates, the inner main shaft IMS rotates in the direction opposite to that during forward movement. The reverse rotation of the inner main shaft IMS is transmitted to the countershaft CS via the gear 43 connected to the planetary gear mechanism 70.

  On the countershaft CS, in order from the left side in FIG. 2, the 2-3 speed driven gear 51, the 6-7 speed driven gear 52, the 4-5 speed driven gear 53, the parking gear 54, and the final drive gear are arranged. 55 is fixedly arranged. The final drive gear 55 meshes with a differential ring gear (not shown) of the differential mechanism 5, whereby the rotation of the output shaft of the countershaft CS becomes the input shaft (that is, the vehicle propulsion shaft) of the differential mechanism 5. Communicated.

  A one-way clutch 41 is provided so as to engage with the ring gear 75 and the planetary gear 72 of the planetary gear mechanism 70.

  When the synchromesh of the 2-6 speed synchromesh mechanism 83 is slid leftward, the 2nd speed drive gear 42 is coupled to the secondary shaft SS, and when slid rightward, the 6th speed drive gear 46 is coupled to the secondary shaft SS. . When the synchromesh of the 4-speed synchromesh mechanism 84 is slid rightward, the 4-speed drive gear 44 is coupled to the secondary shaft SS. By engaging the second clutch C2 with the even-numbered drive gear stage selected in this way, the transmission 4 is set to an even-numbered gear stage (second speed, fourth speed, or sixth speed).

  When the synchromesh of the 3-7 speed synchromesh mechanism 81 is slid to the left, the 3rd speed drive gear 43 is coupled to the inner main shaft IMS to select the 3rd speed, and when it is slid to the right, the 7th speed is driven. The gear 47 is coupled to the inner main shaft IMS to select the seventh speed. When the synchromesh of the 5-speed synchromesh mechanism 82 is slid to the right, the 5-speed drive gear 45 is coupled to the inner main shaft IMS, and the 5-speed gear stage is selected. In a state where none of the synchromesh mechanisms 81, 82 has selected any gears 43, 47, 45, the rotation of the planetary gear mechanism 70 is transmitted to the countershaft CS via the gear 43 connected thereto, so that the first gear stage is changed. Will be selected. By engaging the first clutch C1 with the odd number of drive gears selected in this way, the transmission 4 is set to an odd number of gears (first speed, third speed, fifth speed, or seventh speed). The

  Determination of the shift speed to be realized by the transmission 4 and control for realizing the shift speed (selection of the shift speed in the first transmission mechanism and the second transmission mechanism, that is, synchro switching control, first clutch and second clutch) The control of the engagement and the disengagement is performed by the electronic control unit 10 according to the driving situation as is well known.

  Next, an example of control at the time of engine pushing start executed by the electronic control unit 10 will be described with reference to FIG.

  It is determined that the engine pushing start routine shown in FIG. 4 should be switched to engine running (engine alone running or cooperative running) during motor running (motor alone running) that is a vehicle running using only a motor as a prime mover. When it is done. This engine pushing start routine is roughly divided into a pushing execution subroutine SR1 (first means), a predicted drive gear stage determining subroutine SR2 (second means), and a predicted drive gear stage realizing subroutine SR3 (third means). Note that the execution order of the push execution subroutine SR1 (first means) and the predicted drive gear stage determination subroutine SR2 (second means) may be either first or simultaneously.

  In the pushing execution subroutine SR1 (first means), as a gear stage used for pushing start, a gear stage at which the engine speed at the time of pushing start is equal to or higher than a preset required rotation speed (predetermined engine start speed). Is selected, and the engine is controlled to be pushed and started using the selected gear position. This push execution subroutine SR1 may appropriately use a method known in Patent Document 1 or the like. For example, in this embodiment, since the motor travel is performed at odd gears, the gears that can be used for pushing the engine are all the even gears and the current gears (used for motor travel). Odd-numbered gears). Of the gears that can be used for pushing the engine, the required engine speed (the number of revolutions of the engine crankshaft) when pushing the engine is set in advance (the minimum crankshaft required for pushing and starting the engine). It is determined based on the calculation of the current motor speed and the gear ratio of each gear. If there are multiple gears that exceed the preset required rotational speed, the gear that has the lowest rotational speed (crankshaft speed) (that is, the highest gear) is used for pushing start. Select the gear to be used. The reason why the gear position having the lowest rotation speed out of the required rotation speed (that is, the gear position on the highest speed side) is used for pushing start is to minimize the energy loss of the motor at the time of pushing.

  In the predicted drive gear determination subroutine SR2 (second means), a predicted target drive force predicted after a predetermined time of engine start is obtained based on the current target drive force, and the predicted drive gear stage is determined based on the predicted target drive force. To do. FIG. 5 shows a specific example of the predicted drive gear stage determination subroutine SR2.

  In step S1, the current target driving force Nm is acquired. For example, the current target driving force Nm corresponding to the current accelerator pedal opening AP is acquired by searching a predetermined map by the current accelerator pedal opening AP.

Next, in step S2, a differential value (or amount of change per unit time) ΔNm of the target driving force Nm is calculated, multiplied by a predetermined gain value Gain, and the product is added to the current target driving force Nm. Thus, the predicted target driving force (= Nm + ΔNm × Gain) is calculated. As the gain value Gain, data of the time difference T from the current time point t _c to the predicted time point t _d is used. In this case, the predicted time point t _d is set to a time point after a predetermined time of engine start (ignition). For example, the predicted time point at which the engine travel can be started when the engine start is stably performed. It is. FIG. 6 is a diagram schematically illustrating calculation of the predicted target driving force in step S2. In this example, the predicted target driving force is calculated using a linear function. However, the predicted target driving force may be calculated using any other appropriate non-linear function, or an appropriate table or map. Etc., the predicted target driving force may be obtained (drawn).

  Next, in step S3, a predicted drive gear stage is determined based on the calculated predicted target drive force. This determination may be performed in accordance with a known shift speed determination process. For example, the predicted drive gear position is determined by referring to a predetermined shift map based on the predicted target drive force and the vehicle speed. Note that the determined predicted drive gear stage is the first gear stage for engine running after engine startup.

Note that the predicted drive gear stage determination subroutine SR2 is not limited to a single process, and may be performed many times until the predicted drive gear stage is finally determined. For example, it may be started simultaneously with the start of the pushing execution subroutine SR1 and repeatedly performed in parallel therewith. In that case, the optimal predicted drive gear stage may be determined each time at the current time point t _c that changes from moment to moment, and the final predicted drive gear stage is determined (determined) at the time of engine ignition (first to complete explosion). ) Alternatively, as another embodiment, the predicted drive gear stage subroutine SR2 may be executed once or several times only during engine ignition (initial explosion or complete explosion) to determine (determine) the predicted drive gear stage. .

  Returning to FIG. 4, the predicted drive gear stage realization subroutine SR3 (third means) controls the transmission 4 to realize the determined (determined) predicted drive gear stage. Specifically, a sync used for selecting the predicted drive gear stage is connected, and the first or second clutch C1, C2 is engaged in correspondence with the odd / even number of the predicted drive gear stage. .

  Next, an operation example of the present invention will be described with reference to FIG. FIG. 7 shows an example of a temporal change in the operating state of each device at the time of starting the engine. (A) shows an example of a temporal change in the torque of the motor 3, and (b) shows the first clutch C1 ( (C) shows a temporal change example of the torque of the odd-numbered clutch), (c) shows a temporal change example of the torque of the second clutch C2 (even-numbered clutch), (d) shows the torque of the engine 2 A time change example is shown, and (e) shows a time change example of the rotational speed Ne of the engine 2. Further, (f) shows an example of a gear stage for motor traveling, (g) shows an example of a pushing gear stage, and (h) shows an example of a predicted drive gear stage and a gear stage used for engine traveling. .

  In this example, it is assumed that the motor is traveling alone at the third speed until time t0 (FIG. 7 (f)).

  Time t0 is a time when it is determined that the engine pushing start process should be executed. At this time t0, the process of the pushing execution subroutine SR1 is started. In this example, it is assumed that the fourth speed is selected as the gear position used for pushing start (FIG. 7 (g)). The torque of the second clutch C2 for coupling the even-numbered stages to the engine gradually increases between time points t0 and t1 (FIG. 7 (c)). In addition, since the driving force of the engine is provided while the motor travel is ensured, the torque of the motor 3 gradually increases from the time t0 to the time t1 (FIG. 7A). On the other hand, the first clutch C1 for coupling the odd-numbered gears to the engine remains off (torque 0) (FIG. 7B).

  The engine 2 starts to rotate at time t1 (FIG. 7 (e)). It is detected that the engine 2 has been ignited (initial explosion) at time t2, and it is detected that the engine 2 has been completely exploded at time t3. Between the time points t1 and t3, the torque of the motor 3 and the torque of the second clutch C2 are gradually reduced (FIGS. 7A and 7C). Further, the torque of the engine 2 is generated from the time point t2 (FIG. 7 (d)).

The predicted drive gear stage determination subroutine SR2 starts and executes processing between time points t0 and t3, and at time point t3, it is assumed that the predicted drive gear stage is finally determined (determined). In this example, the second speed is determined as the predicted drive gear stage (FIG. 7 (h)). Incidentally, around the time t4 may be considered generally equivalent to the prediction time t _d of the above.

  Between time t3 and t4, the torque of the second clutch C2 is set to 0 (disengaged), the gear stage (fourth speed) used for pushing is disconnected from the engine 2 (FIG. 7 (c)), and the second The selection of the gear position (fourth speed) used for pushing in the speed change mechanism is canceled (the corresponding synchro is turned off) (FIG. 7 (g)). The predictive drive gear stage realization subroutine SR3 (third means) connects the sync for selecting the predictive drive gear stage during this period (that is, during pushing start), and selects it in the first or second speed change mechanism. Control is performed so as to switch the gear position to the predicted drive gear stage. In this example, a synchromesh mechanism 83 for second speed is connected to the gear 42. In this way, preparation is made so that the predicted drive gear stage can be realized promptly. Further, during the period from the time point t3 to t4, the torque of the motor 3 is maintained at a constant level necessary for motor traveling, and traveling performance is ensured. In this example, the engine speed Ne is increased during this period by further depression of the accelerator pedal (FIG. 7 (e)).

  At time t4, the engagement of the second clutch C2 is started and the torque is gradually increased (FIG. 7 (c)). As a result, the shift speed (second speed) corresponding to the predicted drive gear stage is quickly and smoothly coupled to the engine, and engine travel at the shift speed (second speed) corresponding to the predicted drive gear stage is realized. At this time, the torque of the motor 3 is gradually reduced (FIG. 7A), and the switching from the motor running to the engine running is performed smoothly. Note that at time t4, the engine speed Ne increases due to further depression of the accelerator pedal, and it is determined that the second speed traveling is optimal even in the normal shift map. According to the present invention, according to the above-described prediction, The second gear has already been properly selected. Between time t4 and t5, the change of torque from the motor 3 to the engine 2 is performed, and at time t5, the engine shifts to independent traveling.

  Compared with the prior art, the prior art does not perform the predictive control as in the present invention. For example, at the time t3 when the complete explosion is confirmed, the third gear is selected as the drive gear stage according to the normal shift map. Shift control is implemented such that the third speed is temporarily realized, but the further depression of the accelerator pedal is followed by a kickdown from the third speed to the second speed and a further downshift to the second speed. It was. Therefore, in the embodiment of the present invention, the optimal shift control to the second speed is realized at the time point t4, whereas in the prior art, the control to the third speed is still performed at such a time point. Therefore, there is a response delay such as shifting to the shift control to the second speed. For this reason, in the prior art, there is a delay until the gear stage (for example, the second speed) corresponding to the final required driving force by the driver is realized, and the response is not good. On the other hand, in the present invention, since the predicted drive gear stage is determined based on the predicted target drive force, the gear stage (for example, the second speed) corresponding to the final required drive force by the driver is realized with high responsiveness. Can do.

Furthermore, various embodiments of the present invention are described.
[Aspect 1]
In this aspect, when it is determined that the engine pushing start process should be executed (time t0 in FIG. 7), the process of the predicted drive gear stage determination subroutine SR2 is started to tentatively determine the predicted drive gear stage. In the pushing execution subroutine SR1 (first means) executed in parallel, the tentatively determined predicted drive gear is the current gear (the gear used for motor travel, for example, the third gear). Is a gear position (for example, 5th gear) using a different first speed change mechanism, the speed is equal to or greater than the preset required rotational speed (engine startable speed) in the speed change speed (even speed) of the second speed change mechanism. Is selected, and the second clutch C2 having the selected shift speed is engaged to control the engine 2 to be pushed and started. In the predicted drive gear stage subroutine SR3 (third means), the predicted drive gear stage is switched so as to switch the shift stage selected in the first transmission mechanism to the predicted drive gear stage (for example, the fifth speed) during the pushing start of the engine. A synchromesh mechanism (for example, 82) corresponding to (for example, the fifth speed) is controlled. This control is the same as the processing performed between time points t3 and t4 in FIG. That is, the synchronization control for selecting the predicted drive gear stage is performed separately from the engagement of the first clutch C1 for coupling the first transmission mechanism to the engine (prior to the clutch engagement). In the first speed change mechanism, synchronization to the current shift speed (for example, third speed) is performed in accordance with the synchronization to the predicted drive gear speed (for example, fifth speed). In this way, a quick shift is possible by switching the gear stage selected in the first transmission mechanism to the predicted drive gear stage (for example, switching the synchro so that the predicted drive gear stage is selected) while the engine is pushed and started. It becomes.

[Aspect 2]
In this aspect, in the pushing execution subroutine SR1 (first means), the engine 2 is pushed and started by engaging the first or second clutch having the gear stage selected for the pushing start of the engine 2. Then, in the predicted drive gear stage realization subroutine SR3 (third means), the shift stage to be selected in the first or second transmission mechanism with the predicted drive gear stage during engine pushing start is set as the predicted drive gear stage. Control to switch. This control is also the same as the processing performed between time points t3 and t4 in FIG. That is, the synchronization control for selecting the predicted drive gear stage is performed separately from the engagement of the first or second clutch C1 or C2 for coupling the predicted drive gear stage to the engine (prior to the clutch engagement). Do. In this case as well, the gear stage selected in the first or second transmission mechanism having the predicted drive gear stage is switched to the predicted drive gear stage during the pushing start of the engine (for example, the predicted drive gear stage is selected). By changing the synchro to (1), quick shifting can be achieved.

[Aspect 3]
In this aspect, in the predicted drive gear stage realization subroutine SR3 (third means), in order to realize the determined predicted drive gear stage, the first or second clutch used for pushing the engine is started. The engagement is released and the first or second clutch corresponding to the first or second transmission mechanism having the predicted drive gear stage is controlled to be engaged. When the pushing start clutch and the predicted drive gear stage clutch are the same, the control is as shown in FIG. 7C (temporarily turned off at time points t3 to t4). When the push start clutch and the predicted drive gear stage clutch are different, a clutch different from the disengaged clutch is engaged. By such clutch switching, the speed change mechanism connected to the engine output shaft can be smoothly switched from the push start type to the engine running type, and the unstable behavior at the time of engine start is the drive output of the transmission. Stable shift control can be performed without being transmitted to the shaft.

[Aspect 4]
In this aspect, in the predicted drive gear stage realizing subroutine SR3 (third means), in order to realize the determined predicted drive gear stage, if it is determined that the engine has undergone initial or complete explosion by the pushing, the pushing is performed. The first or second clutch corresponding to the first or second speed change mechanism that has temporarily disengaged the first or second clutch used in the operation and then selected a gear position corresponding to the predicted drive gear speed. Control to engage the second clutch. In the example of FIG. 7, this corresponds to confirming engine ignition (initial explosion or complete explosion) at time t3 and releasing the engagement of the pushing start clutch and engaging the clutch for the predicted drive gear stage. ing. By such clutch switching, the speed change mechanism connected to the engine output shaft can be smoothly switched from the push start type to the engine running type, and the unstable behavior at the time of engine start is the drive output of the transmission. Stable shift control can be performed without being transmitted to the shaft.

[Aspect 5]
In this aspect, in the predicted drive gear stage realizing subroutine SR3 (third means), the shift stage used for the pushing start and the shift stage corresponding to the predicted drive gear stage are different from each other in the shift stage (for example, the second shift mechanism). When the pushing start is the fourth speed and the predicted drive gear stage is the second speed), the gear stage selected by the second speed change mechanism when the engagement of the second clutch C2 used for pushing is once released. Is switched to a gear position (for example, second gear) corresponding to the predicted drive gear stage, and then the second clutch C2 corresponding to the second speed change mechanism that has selected the gear position corresponding to the predicted drive gear stage is engaged. Control to do. This is the same as the example described in FIG. Thus, when different gear stages of the same second speed change mechanism are used as the gear stage for pushing start and the drive gear stage for engine running, the engagement of the second clutch is once released at the end of pushing start, Sometimes, the shift stage selected in the second transmission mechanism is switched to a shift stage corresponding to the predicted drive gear stage (for example, the synchro is replaced), and then the second clutch is engaged again. A smooth and stable gear change can be performed from the gear to the engine gear.

[Aspect 6]
In this aspect, in the predicted drive gear stage realization subroutine SR3 (third means), the shift stage to be selected by the first or second transmission mechanism having the predicted drive gear stage during the pushing start of the engine is the predicted drive. The determined predicted drive gear stage is controlled by engaging the first or second clutch corresponding to the first or second transmission mechanism having the predicted drive gear stage after the engine is started. Is realized. This control is also the same as the processing performed between time points t3 and t4 in FIG. That is, the synchronization control for selecting the predicted drive gear stage is performed prior to the engagement of the first or second clutch C1 or C2 for coupling the predicted drive gear stage to the engine, and then the clutch C1 or C2 is engaged. Engage. As a result, a quick shift is possible, and the engine can be moved when the engine rotation is stabilized.

[Aspect 7]
In this aspect, in the pushing execution subroutine SR1 (first means), the gear stage using the first transmission mechanism in which the predicted drive gear stage is different from the current gear stage (speed stage for motor travel; for example, third speed). (For example, 5th speed), a speed stage (for example, 4th speed) equal to or higher than the engine startable rotation speed is selected from the speed stages of the second speed change mechanism, and the second clutch C2 having the selected speed stage is selected. To engage and start the engine. In the predicted drive gear stage realization subroutine SR3 (third means), the first clutch C1 is engaged simultaneously with switching the shift stage selected in the first speed change mechanism to the predicted drive gear stage (for example, fifth speed). Thus, the determined predicted drive gear stage is realized. For example, at a time point t3 to t4 in FIG. 7, a control that turns on the synchromesh mechanism (for example, 82) corresponding to the predicted drive gear stage (for example, fifth gear) and gradually increases the torque of the first clutch C1 at the same time. I do. As a result, a quick shift can be achieved, and the engine can be moved to the engine quickly. In the first speed change mechanism, synchronization to the current shift speed (for example, third speed) is performed in accordance with the synchronization to the predicted drive gear speed (for example, fifth speed).

1 Vehicle 2 Engine 3 Motor 4 Transmission 5 Differential Mechanism 10 Electronic Control Unit

Claims (8)

A vehicle drive device that is used in a vehicle that includes an internal combustion engine and a motor as a prime mover, and that can shift mechanical power from the internal combustion engine and motor to a vehicle propulsion shaft that engages with drive wheels. And
A first speed change mechanism capable of receiving mechanical power from the engine output shaft and the motor by the first input shaft, shifting the speed by any one of a plurality of shift speeds, and transmitting it to the vehicle propulsion shaft;
A second speed change mechanism capable of receiving mechanical power from the engine output shaft by a second input shaft, shifting the speed by any one of a plurality of shift stages, and transmitting it to the vehicle propulsion shaft;
A first clutch capable of engaging the engine output shaft and the first input shaft;
A second clutch capable of engaging the engine output shaft and the second input shaft;
Control means capable of controlling selection of a gear position in the first transmission mechanism and the second transmission mechanism and an engagement state of the first clutch and the second clutch;
The control means includes
The engine rotational speed at the time of pushing start needs to be set in advance as a shift stage used for the pushing start when the engine is pushed during motor running which is a vehicle running using only a motor as a prime mover A first means for selecting a shift speed that is equal to or higher than the rotation speed and controlling the engine to be pushed and started using the selected shift speed;
Second means for obtaining a predicted target driving force predicted after a predetermined time of engine starting based on a current target driving force and determining a predicted driving gear stage based on the predicted target driving force when the engine is pushed and started. When,
A vehicle drive device comprising: third means for controlling to realize the determined predicted drive gear stage as a shift stage for running the engine after the engine is pushed and started. When using the first speed change mechanism in which the predicted drive gear stage is different from the current speed stage, the first means is equal to or higher than the preset required rotational speed in the speed stage of the second speed change mechanism. Selecting a gear stage, engaging the second clutch with the selected gear stage and controlling the engine to start pushing,
2. The vehicle drive device according to claim 1, wherein the third means performs control so that a shift speed selected in the first speed change mechanism is switched to the predicted drive gear speed during the pushing start of the engine. 3. The first means engages the first or second clutch having a gear selected for starting the engine and engages and starts the engine.
The third means controls to switch the selected gear stage to the predicted drive gear stage in the first or second transmission mechanism with the predicted drive gear stage during the pushing start of the engine. Item 2. The vehicle drive device according to Item 1.   The third means disengages the first or second clutch used for pushing start of the engine in order to realize the determined predicted drive gear stage, and has the predicted drive gear stage. 4. The vehicle drive device according to claim 1, wherein control is performed so that the first or second clutch corresponding to the first or second speed change mechanism is engaged. 5.   In order to realize the determined predicted drive gear stage, the third means determines the first or second explosion of the first or second clutch used for the pushing when it is determined that the engine is first or completely exploded by the pushing. Control is performed so as to engage the first or second clutch corresponding to the first or second speed change mechanism that has once been disengaged and then selected the gear position corresponding to the predicted drive gear stage. The vehicle drive device according to any one of claims 1 to 3.   The third means includes the second clutch used for pushing when the gear stage used for the pushing start and the gear stage corresponding to the predicted drive gear stage are different gear stages of the second transmission mechanism. The gear position selected in the second speed change mechanism when releasing the engagement is switched to the gear position corresponding to the predicted drive gear stage, and then the speed stage corresponding to the predicted drive gear stage is selected. The vehicle drive device according to claim 5, wherein the second clutch corresponding to the two speed change mechanism is controlled to be engaged.   The third means controls to switch the shift stage selected in the first or second transmission mechanism having the predicted drive gear stage to the predicted drive gear stage during the pushing start of the engine, and after the engine starts, 7. The determined predicted drive gear stage is realized by engaging the first or second clutch corresponding to the first or second transmission mechanism having a drive gear stage. The vehicle drive device according to any one of the above. When the predicted drive gear stage is a shift stage using the first transmission mechanism different from the current shift stage, the first means has a speed greater than or equal to the engine startable rotation speed in the shift stage of the second transmission mechanism. Selecting a gear stage, engaging the second clutch with the selected gear stage and controlling the engine to start pushing,
The third means realizes the determined predicted drive gear stage by switching the gear stage selected in the first transmission mechanism to the predicted drive gear stage and simultaneously engaging the first clutch. A vehicle drive device according to any one of claims 1 to 6.

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