JP2013086612A - Speed change control device of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the speed change control device of a hybrid vehicle capable of quickly applying torque of an electric motor to an input shaft, and reducing the load of a synchronizing mechanism provided to a transmission.SOLUTION: In the speed change control device applied to a hybrid vehicle 1 provided with a manual transmission 10, when switching of a gear position is requested to the transmission 10, first, a highest position is set to a target gear position and a target rotation speed is set based on the transmission gear ratio of the highest position. Next, a second clutch 31 is switched to an input shaft-engaged state to perform torque applying processing of applying the torque to an input shaft 11. Then the determination processing is performed for determining whether or not the target gear position matches the requested gear position. In case of determining mismatch in the determination processing, the second clutch 31 is hold in the input shaft-engaged state, and a re-set processing is performed for re-setting the target gear position and target rotation speed. The torque applying processing, determination processing and re-set processing are repeatedly performed until the target gear position matches the requested gear position.

Description

  The present invention relates to a shift control device for a hybrid vehicle including an electric motor capable of adding torque to an input shaft of a transmission.

  A manual transmission that is provided in a power transmission path between the internal combustion engine and the drive wheel, is connected to the input shaft via a clutch, and the transmission ratio is manually changed, and the input of the transmission A vehicle equipped with an electric motor capable of applying torque to a shaft is known. As a shift control device for such a vehicle, when a shift operation is performed, first, a target rotation speed is set based on the predicted gear ratio, and then the actual rotation speed of the input shaft becomes the target rotation speed. An apparatus is known that controls an electric motor and then releases a clutch between the electric motor and an input shaft when the predicted gear ratio does not coincide with the actually changed gear ratio (see Patent Document 1). In addition, Patent Documents 2 and 3 exist as prior art documents related to the present invention.

JP 2001-221330 A JP 2003-274510 A JP 09-0665513 A

  In the device of Patent Document 1, when the predicted gear ratio does not match the actual gear ratio, the input shaft of the transmission and the electric motor are disconnected. Therefore, if it is necessary to add the torque of the electric motor to the input shaft after that, it is necessary to reconnect the input shaft and the electric motor. Therefore, it may take time until the addition of torque to the input shaft is started. is there. Further, in the apparatus of Patent Document 1, when the predicted gear ratio does not match the actual gear ratio, the rotation speed difference is compensated for by a synchro mechanism provided in the transmission. Therefore, a large load may be applied to the synchro mechanism.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a shift control device for a hybrid vehicle that can quickly add torque of an electric motor to an input shaft and can reduce the load on a synchro mechanism provided in the transmission.

  A shift control apparatus for a hybrid vehicle according to the present invention includes a manual transmission that has a plurality of gear stages having different gear ratios set to different sizes, and that can be switched by operating a shift lever. An electric motor connected to the input shaft of the machine via clutch means, and drive wheels connected to the output shaft of the transmission so as to be able to transmit power, the transmission after switching at the time of gear stage switching In a shift control device applied to a hybrid vehicle provided with a synchro mechanism that synchronizes a gear used and a shaft provided with the gear by using a frictional force, the gear stage is switched with respect to the transmission. First, the gear stage having the smallest gear ratio among the plurality of gear stages is set as the target gear stage, and based on the set gear ratio of the target gear stage and the rotation speed of the output shaft. An initial value setting process for setting a target rotational speed is executed, and then the clutch means is switched to an engaged state in which the input shaft and the electric motor are engaged, and the rotational speed of the input shaft is set to the target rotational speed. A torque addition process for adding torque from the electric motor to the input shaft so as to be adjusted, and then the target gear stage matches a requested gear stage that is a required gear stage for the transmission A determination process for determining whether or not the target gear and the required gear are inconsistent in the determination process, the clutch means is maintained in the engaged state, and the plurality of gears Of the stages, the gear stage having the next smallest gear ratio is reset to the target gear stage after the gear stage that has been set to the target gear stage when the determination process is executed, and the reset target gear stage and the output shaft rotation A reset process for resetting the target rotational speed based on the torque, and the torque adding process and the determination until it is determined in the determination process that the target gear stage and the requested gear stage match. And a control means for repeatedly executing the process and the resetting process (claim 1).

  According to the speed change control device of the present invention, when the target gear stage and the required gear stage do not match, the clutch means is maintained in the engaged state, so that it becomes necessary to add the torque of the motor to the input shaft again. Torque can be quickly applied to the. Further, according to the present invention, since the torque of the electric motor is applied to the input shaft until the target gear stage matches the required gear stage, the load on the synchronization mechanism can be reduced.

  In one form of the speed change control device according to the present invention, the control means applies to the input shaft by the electric motor when the rotation speed of the input shaft becomes equal to or higher than a predetermined determination value lower than the target rotation speed in the determination process. And the time differential value of the rotational speed difference, which is the difference between the rotational speed of the input shaft and the target rotational speed, is determined to be less than or equal to a predetermined inclination determination value. When it is determined in the determination process that the time differential value of the rotation speed difference is equal to or less than the inclination determination value, the target gear stage and the target rotation speed may be reset (claim 2). As is well known, when the gear stage is switched, the rotation of the output shaft is transmitted to the input shaft via the synchro mechanism, and the rotation speed of the input shaft is synchronized. At this time, if the target gear stage and the required gear stage do not match, the rotational speed of the input shaft further increases beyond the target rotational speed. In this case, even if the rotational speed of the input shaft is close to the target rotational speed, the change amount of the rotational speed difference per unit time, that is, the gradient of the so-called rotational speed difference remains large. As is well known, the gradient of the rotational speed difference is a time differential value of the rotational speed difference. On the other hand, when the target gear stage and the required gear stage match, the rotational speed of the input shaft is substantially the same as the target rotational speed. Therefore, the time differential value of the rotational speed difference becomes small. Therefore, it is possible to determine whether or not the target gear stage and the required gear stage match based on the time differential value of the rotational speed difference.

  In this embodiment, the control means determines whether the time differential value of the rotation speed difference is equal to or less than the inclination determination value in the determination process, and determines whether the second-order time differential value of the rotation speed difference is less than 0. In the resetting process, when the time differential value of the rotation speed difference is determined to be equal to or less than the inclination determination value and the second-order time differential value of the rotation speed difference is determined to be less than 0, the target gear stage and Each of the target rotational speeds may be reset (claim 3). As is well known, in the rotational speed control, it is known that the rotational speed vibrates across the target rotational speed for a while after the rotational speed reaches the target rotational speed. When the rotational speed vibrates in this way, an inflection point occurs at which the rotational speed difference between the rotational speed and the target rotational speed turns from increasing to decreasing. At this inflection point, the second-order time differential value of the rotational speed difference becomes zero. When the rotational speed difference decreases, the second-order time differential value of the rotational speed difference becomes greater than zero. Therefore, when the target gear stage and the required gear stage match, the rotational speed of the input shaft vibrates across the target rotational speed, and the second-order time differential value of the rotational speed difference becomes 0 or more. On the other hand, when the target gear stage and the required gear stage do not match, the rotational speed of the input shaft further increases beyond the target rotational speed as described above, so the second-order time differential value of the rotational speed difference is It becomes less than 0. In this way, it is possible to determine whether or not the target gear stage and the required gear stage match even using the second-order time differential value of the rotational speed difference. In this embodiment, since it is determined whether or not the target gear stage and the required gear stage match using both the time differential value of the rotational speed difference and the second-order time differential value of the rotational speed difference, the determination accuracy is improved. be able to.

  As described above, according to the speed change control device of the present invention, when the target gear stage and the required gear stage do not match, the clutch means is maintained in the engaged state, so that the torque can be quickly applied. it can. Further, since torque is applied to the input shaft until the target gear stage matches the required gear stage, the load on the synchro mechanism can be reduced.

The figure which shows typically the vehicle incorporating the speed-change control apparatus which concerns on one form of this invention. The figure which shows the shift pattern of the shift lever of a transmission. The flowchart which shows the shift auxiliary | assistant control routine which a control apparatus performs. The flowchart following FIG. The figure which shows an example of the time change of the rotation speed difference when performing the speed change auxiliary control routine and performing speed change. The flowchart which shows the modification of a shift assistance control routine. The figure which shows an example of the time change of the rotation speed of the input shaft at the time of gear shifting. The figure which expands and shows the range A of FIG.

  FIG. 1 schematically shows a vehicle in which a shift control device according to an embodiment of the present invention is incorporated. The vehicle 1 includes an internal combustion engine (hereinafter sometimes referred to as an engine) 2 as a driving power source and a motor generator (hereinafter also abbreviated as MG) 3 as an electric motor. That is, the vehicle 1 is configured as a hybrid vehicle. The engine 2 is a well-known spark ignition type internal combustion engine having four cylinders. The engine 2 is provided with a starter 2a for starting the engine 2. The MG 3 is a well-known device that is mounted on a hybrid vehicle and functions as an electric motor and a generator. The MG 3 is electrically connected to the battery 4. A transmission 10 is mounted on the vehicle 1, and the engine 2 and the MG 3 are connected to the transmission 10. The transmission 10 is also connected to an output unit 6 for outputting power to the drive wheels 5 of the vehicle 1. The output unit 6 includes an output gear 7 and a differential mechanism 8 connected to the drive wheel 5. The output gear 7 is attached to the output shaft 12 of the transmission 10 so as to rotate integrally. Further, the output gear 7 meshes with a ring gear 8 a provided in the case of the differential mechanism 8. The differential mechanism 8 is a known mechanism that distributes the transmitted power to the left and right drive wheels 5.

  The transmission 10 includes an input shaft 11 and an output shaft 12. Between the input shaft 11 and the output shaft 12, first to fifth transmission gear pairs G1 to G5 and a reverse gear group GR are provided. The first transmission gear pair G1 is composed of a first drive gear 13 and a first driven gear 14 that mesh with each other, and the second transmission gear pair G2 is composed of a second drive gear 15 and a second driven gear 16 that mesh with each other. Yes. The third transmission gear pair G3 is composed of a third drive gear 17 and a third driven gear 18 that mesh with each other, and the fourth transmission gear pair G4 is composed of a fourth drive gear 19 and a fourth driven gear 20 that mesh with each other. Yes. The fifth transmission gear pair G5 includes a fifth drive gear 21 and a fifth driven gear 22 that mesh with each other. The first to fifth transmission gear pairs G1 to G5 are provided so that the drive gear and the driven gear are always meshed. Different gear ratios are set for the respective transmission gear pairs G1 to G5. The gear ratio is set so as to decrease in the order of the first transmission gear pair G1, the second transmission gear pair G2, the third transmission gear pair G3, the fourth transmission gear pair G4, and the fifth transmission gear pair G5. The reverse gear group GR includes a reverse drive gear 23, an intermediate gear 24, and a reverse driven gear 25.

  The first to fifth drive gears 13, 15, 17, 19, and 21 are supported on the input shaft 11 so as to be rotatable relative to the input shaft 11. The reverse drive gear 23 is fixed to the input shaft 11 so as to rotate integrally with the input shaft 11. As shown in this figure, these gears are arranged in the order of the reverse drive gear 23, the first drive gear 13, the second drive gear 15, the third drive gear 17, the fourth drive gear 19, and the fifth drive gear 21 in this order. It is arranged to line up in the direction. The first to fifth driven gears 14, 16, 18, 20, 22 and the reverse driven gear 25 are fixed to the output shaft 12 so as to rotate integrally with the output shaft 12.

  The input shaft 11 is provided with first to fourth sleeves 26 to 29. The first to third sleeves 26 to 28 are supported by the input shaft 11 so as to rotate integrally with the input shaft 11 and be movable in the axial direction. The fourth sleeve 29 is supported on the input shaft 11 so as to be rotatable relative to the input shaft 11 and movable in the axial direction. The first sleeve 26 and the fourth sleeve 29 are provided between the first drive gear 13 and the reverse drive gear 23. The second sleeve 27 is provided between the second drive gear 15 and the third drive gear 17. The third sleeve 28 is provided between the fourth drive gear 19 and the fifth drive gear 21.

  The first sleeve 26 is provided so as to be switchable between a first speed position where the input shaft 11 and the first drive gear 13 rotate together, and a release position where the engagement is released. ing. The second sleeve 27 has a second speed position at which the input shaft 11 and the second drive gear 15 mesh with the second drive gear 15 so that the input shaft 11 and the second drive gear 15 rotate integrally, and the input shaft 11 and the third drive gear 17 rotate integrally. Thus, the third speed gear position that meshes with the third drive gear 17 and the release position that does not mesh with any of the second drive gear 15 and the third drive gear 17 can be switched. The third sleeve 28 has a fourth speed position at which the input shaft 11 and the fourth drive gear 19 mesh with the fourth drive gear 19 so that the input shaft 11 and the fourth drive gear 19 rotate integrally, and the input shaft 11 and the fifth drive gear 21 rotate integrally. Thus, it is provided so as to be switchable between a fifth speed position that meshes with the fifth drive gear 21 and a release position that does not mesh with either the fourth drive gear 19 or the fifth drive gear 21. Although not shown in the figure, the rotation of the input shaft 11 is synchronized when the first to third sleeves 26 to 28 and the first to fifth drive gears 13, 15, 17, 19, and 21 are meshed. A plurality of synchronization mechanisms are provided. For these synchro mechanisms, a synchro mechanism that synchronizes rotation by friction engagement, for example, a known key-type synchromesh mechanism may be used. Therefore, detailed description of the synchro mechanism is omitted.

  The fourth sleeve 29 supports the intermediate gear 24 rotatably. The intermediate gear 24 moves in the axial direction together with the fourth sleeve 29. The fourth sleeve 29 can be switched between a reverse position where the intermediate gear 24 meshes with each of the reverse drive gear 23 and the reverse driven gear 25 and a release position where the mesh between the intermediate gear 24 and each of the gears 23 and 25 is released. Is provided.

  As shown in this figure, the engine 2 is connected to the input shaft 11 via the first clutch 30. The first clutch 30 is a known clutch that can be switched between an engaged state in which power is transmitted between the engine 2 and the input shaft 11 and a released state in which the power transmission is interrupted. The first clutch 30 is operated by the clutch pedal 9. The first clutch 30 switches to a released state when the clutch pedal 9 is depressed, and switches to an engaged state when the depression is released.

  The rotor shaft 3a of the MG 3 is provided with a second clutch 31 as a clutch means and an intermediate member 32. The intermediate member 32 is supported by the rotor shaft 3a so as to be relatively rotatable. A constantly meshing gear pair 33 is provided between the intermediate member 32 and the output shaft 12. The gear pair 33 includes a first gear 34 that is fixed to the output shaft 12, and a second gear 35 that is fixed to the intermediate member 32 and meshes with the first gear 34. The second clutch 31 has an input shaft engagement state in which the rotor shaft 3a and the input shaft 11 are engaged with each other so that the rotor shaft 3a and the input shaft 11 rotate integrally, and the rotor shaft 3a and the intermediate member 32 are integrally rotated. It is configured to be switchable between an engaged output shaft engagement state and a released state in which the rotor shaft 3a is not engaged with either the input shaft 11 or the output shaft 12. As the second clutch 31, for example, a well-known clutch may be used in which a sleeve that rotates integrally with the rotor shaft 3a is provided and the position of the sleeve is switched to switch the engagement destination.

  Each sleeve 26 to 29 of the transmission 10 is connected to a shift lever 36 operated by a driver. FIG. 2 shows a shift pattern 37 of the shift lever 36. The shift pattern 37 includes a select path 38 extending in the left-right direction in the figure and seven shift paths 39 extending from the select path 38 in the vertical direction in the figure. The shift lever 36 is provided so as to be movable along the select path 38 and the shift paths 39. As shown in this figure, the seven shift paths 39 are set with 1st to 5th speed, reverse R, and EV travel EV. For the 1st to 5th speeds, only numbers are shown as in the known shift pattern. Neutral N is set in the select path 38.

  In the shift pattern 37, when the shift lever 36 is operated to the first speed, the first sleeve 26 is switched to the first speed position, and the second to fourth sleeves 27 to 29 are switched to the release position. When the shift lever 36 is operated to the second speed, the second sleeve 27 is switched to the second speed position, and the first, third, and fourth sleeves 26, 28, and 29 are switched to the release position. When the shift lever 36 is operated to the third speed, the second sleeve 27 is switched to the third speed position, and the first, third, and fourth sleeves 26, 28, and 29 are switched to the release position. When the shift lever 36 is operated to the fourth speed, the third sleeve 28 is switched to the fourth speed position, and the first, second, and fourth sleeves 26, 27, and 29 are switched to the release position. When the shift lever 36 is operated to the fifth speed, the third sleeve 28 is switched to the fifth speed position, and the first, second, and fourth sleeves 26, 27, and 29 are switched to the release position. When the shift lever 36 is operated to reverse R, the fourth sleeve 29 is switched to the reverse position, and the first to third sleeves 26 to 28 are switched to the release position. When the shift lever 36 is operated to EV traveling EV or neutral N, the first to fourth sleeves 26 to 29 are switched to the release position. As described above, the shift lever 36 and the sleeves 26 to 29 are connected to each other. Therefore, the transmission 10 is configured as a so-called manual transmission in which a driver operates the shift lever 36 to change speed.

  In the vehicle 1, a plurality of travel modes are realized by controlling the operations of the engine 2, the MG 3, and the second clutch 31. As the plurality of travel modes, an engine travel mode that travels using the power of the engine 2, an HV travel mode that travels using the power of both the engine 2 and the MG3, and an EV travel mode that travels using only the power of the MG3 are set. The engine travel mode and the HV travel mode are executed when the shift lever 36 is operated from the first speed to the fifth speed or reverse R. Note that switching between the engine travel mode and the HV travel mode is appropriately performed according to the speed, torque, and the like required for the vehicle 1. The EV traveling mode is executed when the shift lever 36 is operated to the EV traveling EV position.

  In the engine travel mode, the engine 2 is switched to the operating state, and the second clutch 31 is switched to the released state. Then, the transmission 10 is appropriately switched from the first speed to the fifth speed or reverse R by the driver. In the HV travel mode, the second clutch 31 is switched from the engine travel mode state to the input shaft engagement state or the output shaft engagement state. And let MG3 function as an electric motor. In the EV traveling mode, since the shift lever 36 is operated to the EV traveling EV, the first to fourth sleeves 26 to 29 are switched to the release position as described above. Further, the engine 2 is stopped. The second clutch 31 is switched to the output shaft engaged state, and causes the MG 3 to function as an electric motor.

  Operations of the engine 2, the MG 3, and the second clutch 31 are controlled by the control device 50. The control device 50 is configured as a computer unit including a microprocessor and peripheral devices such as RAM and ROM necessary for its operation. The control device 50 holds various control programs for causing the vehicle 1 to travel appropriately. The control device 50 controls these control objects such as the engine 2 and the MG 3 by executing these programs. Various sensors for acquiring information related to the vehicle 1 are connected to the control device 50. For example, a clutch pedal sensor 51 that outputs a signal when the clutch pedal 9 is depressed, a vehicle speed sensor 52 that outputs a signal corresponding to the speed of the vehicle 1, and a signal corresponding to the rotational speed of the input shaft 11 are output. An input shaft rotational speed sensor 53 and the like are connected. Further, as shown in FIG. 2, the control device 50 corresponds to whether or not the neutral sensor 54 that outputs a signal corresponding to whether or not the shift lever 36 is in the neutral N, and whether or not the shift lever 36 is in the EV traveling EV. An EV travel sensor 55 that outputs the signal and a reverse sensor 56 that outputs a signal corresponding to whether or not the shift lever 36 is in the reverse R are also connected. In addition to this, various sensors are connected to the control device 50, but they are not shown.

  The control device 50 executes control for assisting the gear shift when the gear shift is requested to the transmission 10. As is well known, the synchronizing mechanism synchronizes the rotational speed of the input shaft 11 with the rotational speed of the drive gear used after the speed change. In this control, torque is applied from the MG 3 to the input shaft 11 at the time of shifting to assist the synchronization of the rotational speed. 3 and 4 show a shift assist control routine executed by the control device 50 to assist the shift in this way. FIG. 4 is a flowchart following FIG. This control routine is repeatedly executed at a predetermined cycle while the vehicle 1 is traveling. In addition, this control routine is executed in parallel with other routines executed by the control device 50.

  In this control routine, the control device 50 first acquires the traveling state of the vehicle 1 in step S11. As the running state of the vehicle 1, for example, the rotational speed of the input shaft 11 and the speed of the vehicle 1 are acquired. In the next step S12, the control device 50 determines whether or not the vehicle 1 is traveling free-running. In the free-run traveling, the sleeves 26 to 29 of the transmission 10 are in the disengaged position and the second clutch 31 is in the input shaft connected state or in the disengaged state, and the drive wheels 5 are disconnected from the engine 2 and the MG 3. Indicates a traveling state where the vehicle is traveling by inertia. If it is determined that the vehicle is not free-running, the current control routine is terminated.

  On the other hand, if it is determined that the vehicle is in free-running, the process proceeds to step S13, and the control device 50 determines whether or not a clutch disengagement operation in which the clutch pedal 9 is depressed is performed. This determination may be made with reference to the output signal of the clutch pedal sensor 51. If it is determined that the clutch disengagement operation has not been performed, the current control routine is terminated. On the other hand, when it is determined that the clutch disengagement operation has been performed, the process proceeds to step S14, and the control device 50 determines whether or not a predetermined input shaft connection condition is satisfied. For example, it is determined that the input shaft connection condition is satisfied when the MG 3 cannot be connected to the output shaft 12 and the shift lever 36 is not in the neutral N, EV traveling EV, or reverse R position. The case where the MG 3 cannot be connected to the output shaft 12 is set, for example, when the vehicle 1 is traveling at a high speed. The case where the shift lever 36 is not in the neutral N, EV traveling EV, or reverse R position indicates that the shift lever 36 has been moved to any one of the first to fifth shift paths 39. That is, it is indicated that the transmission 10 is requested to shift to any one of the first speed to the fifth speed. If it is determined that the input shaft connection condition is not satisfied, the current control routine is terminated.

  On the other hand, if it is determined that the input shaft connection condition is satisfied, the process proceeds to step S15, and the control device 50 switches the second clutch 31 to the input shaft engaged state to connect the MG 3 and the input shaft 11. In subsequent step S16, the control device 50 sets initial values of the target gear stage Gear_t and the target rotational speed Nin_t. The target rotational speed Nin_t is the rotational speed of the input shaft 11 to be controlled by the MG 3 at the time of shifting. In the target gear stage Gear_t, the highest stage of the transmission 10, that is, the fifth speed is set as an initial value. Further, the target rotation speed Nin_t is calculated based on the rotation speed of the output shaft 12 and the fifth gear ratio.

  In the next step S17, the control device 50 determines whether or not the input shaft rotational speed Nin is less than a value obtained by subtracting the target correction value N1 from the target rotational speed Nin_t (hereinafter, this value may be referred to as a determination value). . The target correction value N1 is a value set for stopping the application of torque from the MG 3 to the input shaft 11 before the input shaft rotational speed Nin reaches the target rotational speed Nin_t. The target correction value N1 is set based on the current vehicle speed and the target gear stage Gear_t. Note that the target correction value N1 is obtained in advance as a map in the ROM of the control device 50 by obtaining the relationship between the vehicle speed and the target gear stage Gear_t and the target correction value N1 in advance by experiments or numerical calculations, for example. Can be set. If it is determined that the input shaft rotational speed Nin is greater than or equal to the determination value, steps S18 and S19 are skipped and the process proceeds to step S20. On the other hand, if it is determined that the input shaft rotational speed Nin is less than the determination value, the process proceeds to step S18, and the control device 50 executes MG positive torque addition control. In this MG positive torque addition control, a positive torque is applied from the MG 3 to the input shaft 11 so that the input shaft rotational speed Nin becomes the above-described determination value. The positive torque is torque that rotates the input shaft 11 in the rotational direction of the engine 2. In the next step S19, the control device 50 determines whether or not the input shaft rotational speed Nin is greater than or equal to a determination value. If it is determined that the input shaft speed Nin is less than the determination value, the process returns to step S17.

  On the other hand, if it is determined that the input shaft rotational speed Nin is greater than or equal to the determination value, the process proceeds to step S20, and the control device 50 stops applying torque from the MG 3 to the input shaft 11. In the next step S21, the control device 50 determines whether or not the time differential value of the rotational speed difference sub (Nin), which is a value obtained by subtracting the current input shaft rotational speed Nin from the target rotational speed Nin_t, is equal to or smaller than the inclination determination value N2. . FIG. 5 shows an example of a change over time in the rotational speed difference sub (Nin) when the shift assist control routine is executed to perform a shift. This figure shows the time change of the rotational speed difference sub (Nin) when the transmission 10 is shifted to the fifth speed and when the transmission 10 is shifted to the fourth speed. The solid line indicates the time change when the gear is shifted to the fifth speed, and the broken line indicates the time change when the gear is shifted to the fourth speed. In this figure, the transmission 10 is shifted at time T1. As described above, in this control, the fifth gear is set as the initial value for the target gear stage. Therefore, when the speed is actually changed to the fifth speed, the change amount per unit time of the rotational speed difference sub (Nin) becomes small as shown by the solid line when the input shaft rotational speed Nin becomes less than the determination value. . On the other hand, when the speed is actually changed to the fourth speed, the change amount per unit time of the rotational speed difference sub (Nin) as shown by the broken line even if the input shaft rotational speed Nin becomes less than the determination value. Remains large. The time differential value of the rotational speed difference sub (Nin) is the slope of the rotational speed difference sub (Nin). Therefore, as is clear from this figure, when the actual gear stage and the target gear stage coincide with each other, the differential value of the rotational speed difference sub (Nin) becomes small, and the actual gear stage and the target gear stage become smaller. If they are different, the differential value of the rotational speed difference sub (Nin) becomes large. The inclination determination value N2 is set to determine whether or not the actual gear stage matches the target gear stage. The inclination determination value N2 is set based on the current vehicle speed and the target gear stage Gear_t. Note that the inclination determination value N2 is obtained in advance as a map in the ROM of the control device 50 by obtaining the relationship between the vehicle speed and the target gear stage Gear_t and the inclination determination value N2 in advance by, for example, experiment or numerical calculation. Can be set.

  If it is determined that the time differential value of the rotational speed difference sub (Nin) is greater than the inclination determination value N2, step S22 is skipped and the process proceeds to step S23. On the other hand, when it is determined that the time differential value of the rotation speed difference sub (Nin) is equal to or smaller than the inclination determination value N2, the process proceeds to step S22, and the control device 50 changes the target gear stage Gear_t and the target rotation speed Nin_t. In this process, the target gear stage Gear_t is changed to a gear stage that is one smaller than the previously set gear stage. For example, if the fifth speed has been set until then, the speed is changed to the fourth speed. The target rotational speed Nin_t is set based on the changed target gear stage Gear_t and the rotational speed of the output shaft 12.

  In the next step S23, the control device 50 determines whether or not a clutch engagement operation for releasing the depression of the clutch pedal 9 has been performed. If it is determined that the clutch engagement operation is not performed, the process returns to step S17, and the processes of steps S17 to S23 are repeatedly executed until the clutch engagement operation is performed. On the other hand, if it is determined that the clutch engagement operation has been performed, the current control routine is terminated.

  As described above, according to the present invention, since the fifth gear is first set as the target gear stage, the torque to be applied from the MG 3 to the input shaft 11 can be reduced. When the actual gear stage is different from the target gear stage Gear_t, the second clutch 31 is not released, and the target gear stage Gear_t is changed to apply more torque to the input shaft 11. Therefore, torque can be quickly applied to the input shaft 11. Further, the rotation speed synchronization of the input shaft 11 can be assisted until the target gear stage Gear_t matches the actual gear stage. Accordingly, it is possible to reduce the load applied to the synchronization mechanism.

  As is well known, if torque is applied until the rotational speed of the input shaft 11 reaches the target rotational speed Nin_t, the rotational speed of the input shaft 11 may further increase after reaching the target rotational speed Nin_t. In this case, the rotational speed vibrates so as to match the rotational speed of the input shaft 11 with the target rotational speed Nin_t. On the other hand, in the present invention, the application of torque to the input shaft 11 is stopped before the rotational speed of the input shaft 11 reaches the target rotational speed Nin_t. Therefore, it is possible to reduce the vibration of the rotation speed after the rotation speed of the input shaft 11 reaches the target rotation speed Nin_t.

  The control device 50 functions as the control means of the present invention by executing the shift assist control routine. Step S16 corresponds to the initial value setting process of the present invention, and step S18 corresponds to the torque addition process of the present invention. Further, steps S19 to S21 correspond to the determination process of the present invention, and step S22 corresponds to the resetting process.

  A modification of the shift assist control routine will be described with reference to FIG. FIG. 6 shows a part of the control routine of this modification. This modification is different from the above-described shift assist control routine in that steps S30 and S31 are added between step S21 and step S22, and the rest is the same. For this reason, the same processes are denoted by the same reference numerals and description thereof is omitted. In this figure, the process after step S20 is shown. Also in this modification, FIG. 3 is referred to for the process before step S20.

  As described above, the sleeves 26 to 29 of the transmission 10 are connected so as to interlock with the shift lever 36. Therefore, the speed at which each of the sleeves 26 to 29 moves may be referred to as the magnitude of the force with which the driver operates the shift lever 36 (hereinafter also referred to as shift operation force) or the speed at which the driver operates (hereinafter referred to as shift operation speed). .) To change. FIG. 7 shows an example of a temporal change in the rotational speed of the input shaft 11 at the time of shifting. In this figure, solid lines SL1 to SL3 indicate time variations of the rotational speed of the input shaft 11 when the shift operation force is small, and broken lines BL1 to BL3 indicate time variations of the rotational speed of the input shaft 11 when the shift operation force is large. Is shown. Further, in this figure, the rotational speed Nin_5th is the target rotational speed when the target gear stage is the fifth speed, the rotational speed Nin_4th is the target rotational speed when the target gear stage is the fourth speed, and the rotational speed Nin_3rd is the target gear stage 3 The target rotational speed at the time of speed is shown respectively.

  When the shift operation force is large, the force (hereinafter sometimes referred to as pressing force) by which the synchro ring of the synchro mechanism is pressed against the cone portion of the drive gear is large. As a result, the input shaft speed rapidly increases as indicated by broken lines BL1 to BL3 in this figure. On the other hand, when the shift operation force is small, the pressing force is small, so that the input shaft rotational speed slowly increases as indicated by solid lines SL1 to SL3 in the figure. Thus, the time change of the input shaft rotation speed at the time of shifting changes according to the shift operation force. When the shift operation force is large and the rotation speed of the input shaft 11 rapidly increases, the inclination of the rotation speed difference sub (Nin) may increase even if the target gear stage Gear_t matches the actual gear stage. . For this reason, if it is determined only by the time differential value of the rotational speed difference sub (Nin) whether or not the target gear stage Gear_t and the actual gear stage coincide with each other, there is a risk of erroneous determination. Therefore, in this modification, it is determined whether or not the target gear stage should be changed in consideration of the shift operation force and the shift operation speed.

  In the shift assist control routine of this modification, the control device 50 proceeds with the process up to step S21 as in the control routine shown in FIG. When it is determined in step S21 that the time differential value of the rotational speed difference sub (Nin) is equal to or smaller than the inclination determination value N2, the process proceeds to step S30, and the control device 50 determines whether or not the input shaft rotational speed Nin is equal to or greater than the target rotational speed Nin_t. To do. When the input shaft speed Nin is less than the target speed Nin_t, this process is repeatedly executed until the input shaft speed Nin becomes equal to or higher than the target speed Nin_t. When the input shaft speed Nin is equal to or higher than the target speed Nin_t, the process proceeds to step S31, and the control device 50 determines whether or not the input shaft speed Nin is oscillating. FIG. 8 shows the range A of FIG. 7 in an enlarged manner. In this figure, the solid line SL3 is not shown. As shown in this figure, when the target gear stage matches the actual gear stage, the input shaft rotational speed Nin vibrates after reaching the target rotational speed Nin_t. This vibration similarly occurs in any gear stage from 1st gear to 5th gear. Therefore, when this vibration is detected, it can be determined that the target gear stage matches the actual gear stage. When the input shaft rotational speed Nin vibrates, an inflection point occurs at which the input shaft rotational speed Nin turns from increasing to decreasing. Therefore, in this process, when the input shaft rotational speed Nin is within a predetermined rotational speed range equal to or larger than the target rotational speed Nin_t, it is determined whether or not the input shaft rotational speed Nin is oscillating using the following equation (1). .

  As shown in this equation (1), when the second-order time differential value of the rotation speed difference sub (Nin) is less than 0, no inflection point has occurred. Therefore, it can be determined that the input shaft speed Nin is not vibrating. As the predetermined rotation speed range, for example, as shown in FIG. 8, a range between a target rotation speed Nin_t and a range upper limit value Nin_t + α obtained by adding a predetermined value α to the target rotation speed Nin_t is set. The predetermined value α may be set appropriately so that the range upper limit value Nin_t + α is slightly higher than the upper limit value during vibration of the input shaft rotational speed Nin.

  If it is determined that the input shaft speed Nin is vibrating, the process proceeds to step S23. On the other hand, when it determines with the input rotation speed Nin not vibrating, it progresses to step S22. After step S22 or S23, the process proceeds in the same manner as the shift assist control routine shown in FIGS.

  In this modification, it is also determined using the second-order time differential value of the rotational speed difference sub (Nin) whether or not the target gear stage matches the actual gear stage. Therefore, it is possible to prevent erroneous determination of the target gear stage based on the variation in the shift operation force of the driver. Thus, by improving the determination accuracy, the load on the synchro mechanism can be further reduced.

  In this modification, steps S19 to S21, S30, and S31 correspond to the determination process of the present invention.

  The present invention is not limited to the above-described form and can be implemented in various forms. For example, the transmission to which the present invention is applied is not limited to a transmission having a maximum speed of 5 speeds. The present invention may be applied to a transmission in which the fourth speed or the sixth speed is the highest. In this case, the highest stage of these transmissions is set as the initial value of the target gear stage. That is, if the highest gear is a six-speed transmission, the initial value of the target gear is set to sixth.

  The synchromesh mechanism of the transmission provided in the present invention is not limited to the key type synchromesh mechanism. The transmission provided in the present invention may be provided with various synchro mechanisms that synchronize the rotating shaft and the gear by using frictional force during shifting. Further, the transmission is not limited to a transmission in which a synchronization mechanism is provided on the input shaft. For example, a transmission in which each drive gear is provided to rotate integrally with an input shaft, each driven gear is supported so as to be relatively rotatable with respect to an output shaft, and a synchro mechanism is provided between the output shaft and the driven gear. There may be.

1 Vehicle 3 Motor generator (electric motor)
5 Drive Wheel 10 Transmission 11 Input Shaft 12 Output Shaft 31 Second Clutch (Clutch Means)
36 Shift lever 50 Control device (control means)
N2 inclination judgment value

Claims (3)

A manual type transmission having a plurality of gear stages with different speed ratios set to each other, the gear stage being switched by operating a shift lever, and a clutch means connected to the input shaft of the transmission A drive wheel connected to the output shaft of the transmission so as to be able to transmit power,
Shift control applied to a hybrid vehicle provided with a synchro mechanism that synchronizes a gear used after switching at the time of switching of a gear stage and a shaft provided with the gear by using frictional force in the transmission. In the device
When the transmission is requested to change gear positions, the gear stage having the smallest gear ratio among the plurality of gear stages is first set as the target gear stage, and the gear ratio of the set target gear stage and the An initial value setting process for setting a target rotational speed based on the rotational speed of the output shaft is performed, and then the clutch means is switched to an engaged state in which the input shaft and the electric motor are engaged, and the input shaft Torque addition processing for adding torque from the electric motor to the input shaft is executed so that the rotation speed is adjusted to the target rotation speed, and then the target gear stage is a gear stage requested for the transmission. A determination process is performed to determine whether or not the required gear stage matches, and if the target gear stage and the required gear stage are determined to be inconsistent in the determination process, the clutch means is brought into the engaged state. Wei And, among the plurality of gear stages, the gear stage having the next smallest gear ratio after the gear stage that has been set as the target gear stage at the time of execution of the determination process is reset to the target gear stage and reset. A reset process for resetting the target rotational speed is executed based on the gear speed and the rotational speed of the output shaft, and it is determined in the determination process that the target gear speed and the required gear speed are the same. A shift control apparatus comprising control means for repeatedly executing the torque addition process, the determination process, and the resetting process until a predetermined time is reached.   The control means stops addition of torque to the input shaft by the electric motor when the rotational speed of the input shaft becomes equal to or higher than a predetermined determination value lower than the target rotational speed in the determination process, and the input shaft It is determined whether the time differential value of the rotational speed difference, which is the difference between the rotational speed of the engine and the target rotational speed, is equal to or smaller than a predetermined inclination determination value. In the resetting process, the time differential of the rotational speed difference is determined in the determining process The shift control apparatus according to claim 1, wherein when the value is determined to be equal to or less than the inclination determination value, the target gear stage and the target rotation speed are reset.   The control means determines whether the time differential value of the rotation speed difference is equal to or less than the inclination determination value in the determination process, determines whether the second-order time differential value of the rotation speed difference is less than 0, and In the setting process, when the time differential value of the rotation speed difference is determined to be equal to or less than the inclination determination value, and the second-order time differential value of the rotation speed difference is determined to be less than 0, the target gear stage and the target rotation speed The shift control device according to claim 2, wherein each of the gears is reset.

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