JP2012030727A - Control device of vehicle transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of vehicle transmission system that can reduce load applied to an engagement clutch while being able to suppress shock generated when connecting the engagement clutch.SOLUTION: Since connection of a synchronization clutch 42 during vehicle traveling is carried out while the torque Tm of an electric motor 30 is nearly zero, torque transmission of an electric motor 30 to a front wheel shaft 26 does not occur when connecting the clutch, and shock occurs when connecting can be suppressed. Since the torque Tm of the electric motor 30 is zero when connecting the synchronization clutch, if the rotation speeds before and after the synchronization clutch 42 are synchronized, the synchronization clutch 42 is smoothly connected, and load concerning the synchronization clutch 42 is reduced and deterioration of durability of the synchronization clutch 42 is suppressed.

Description

  The present invention relates to a control device for a vehicle power transmission device, and more particularly to a control device for a vehicle power transmission device having a configuration in which an electric motor is connected to a drive shaft via a clutch so that power can be transmitted.

  2. Description of the Related Art A vehicle power transmission device having a configuration in which a driving force of an electric motor is transmitted to driving wheels via a clutch is well known. For example, the power transmission device described in Patent Document 1 is an example. The power transmission device of Patent Document 1 is configured to travel with the driving force of an electric motor by connecting a clutch in a low vehicle speed range. Further, the clutch is kept connected even in the parking state where the ignition is turned off, so that the vehicle can be started by the driving force of the electric motor.

JP 2007-192336 A

  By the way, in the power transmission device of Patent Document 1, when the vehicle speed is equal to or lower than a predetermined value, the driving state is exclusively switched from the driving state using the engine as the driving source to the driving state by connecting the clutch. When the clutch is connected, rotation control by the electric motor is performed so that the differential rotation between the rotational speed on the motor side of the clutch and the rotational speed on the drive shaft side is reduced. At this time, since the clutch is connected while performing the rotation control by the electric motor, there is a problem in that the torque (driving force) generated by the rotation control of the electric motor causes the vehicle occupant to be pushed out or pulled in when the clutch is connected. In addition, it is difficult to connect the clutch while completely synchronizing the differential rotation before and after the clutch, that is, the rotational speed on the electric motor side and the rotational speed on the drive shaft side. By engaging the clutch, there is a problem that a load is applied to the clutch and the durability of the clutch is lowered.

  The present invention has been made against the background of the above circumstances, and an object thereof is a vehicle power transmission device including a meshing clutch capable of intermittently connecting a power transmission path between an electric motor and a drive wheel. In addition, it is possible to suppress a shock (a feeling of being pushed out or pulled in) that is generated when the meshing clutch is connected, and it is possible to reduce a load applied to the meshing clutch and suppress a decrease in durability of the meshing clutch. It is to provide a control device for a transmission device.

  In order to achieve the above object, the gist of the invention according to claim 1 is that: (a) a power transmission path between the electric motor and the drive shaft, the motor-side meshing member driven by the motor and the driving thereof; A control device for a vehicle power transmission device having a meshing clutch that is connected to or disengaged from each other by being connected to or disengaged from a drive shaft side meshing member coupled to a shaft, and (b) The engagement clutch is connected in a state where the torque of the electric motor is zero or substantially zero.

  According to a second aspect of the present invention, there is provided a control device for a vehicle power transmission device according to the first aspect, wherein the motor side meshing is performed by the motor when the meshing clutch is connected while the vehicle is running. After raising the rotational speed of the member to a rotational speed greater than the rotational speed of the drive shaft side meshing member, the motor side meshing member and the drive shaft side of the meshing clutch in a state where the torque of the motor is zero or substantially zero A predetermined pressing force for urging the coupling member for meshing with the meshing member toward the clutch connection side is applied to the meshing clutch.

  The gist of the invention according to claim 3 is that, in the control device for a vehicle power transmission device according to claim 2, the point of time when the rotational speed of the electric motor is increased is increased as the rate of change of the vehicle speed increases. It is characterized by.

  The gist of the invention according to claim 4 is that, in the control device for a vehicle power transmission device according to claim 2 or 3, the rate of change in rotational speed when the rotational speed of the electric motor is increased is the rate of change in vehicle speed. It is characterized in that it increases as the value increases.

  According to a fifth aspect of the present invention, there is provided a control device for a vehicle power transmission device according to any one of the second to fourth aspects, wherein the rotational speed of the motor-side meshing member by the motor is the driving speed. When the motor is pulled up to a first rotational speed that is higher than the rotational speed of the shaft-side meshing member, the motor is maintained at the first rotational speed until the torque of the electric motor is zero or substantially zero.

  According to a sixth aspect of the present invention, in the control device for a vehicle power transmission device according to any one of the second to fifth aspects, the torque of the motor is a rotational speed of the drive shaft side meshing member. Is set to zero or substantially zero when reaching a preset second rotational speed lower than the first rotational speed, and the second rotational speed increases as the rate of change of the vehicle speed increases. It is set to a value.

  According to a seventh aspect of the present invention, in the control device for a vehicle power transmission device according to any one of the first to sixth aspects, the engagement / disengagement of the meshing clutch is switched via an actuator. Features.

  A gist of the invention according to claim 8 is that, in the control device for a vehicle power transmission device according to any one of claims 1 to 7, the meshing clutch is a meshing clutch provided with a synchronization mechanism. Features.

  According to the control device for a vehicle power transmission device of the first aspect of the present invention, since the engagement of the meshing clutch while the vehicle is running is performed in a state where the torque of the electric motor is zero or substantially zero, As the torque transmission of the electric motor to the drive shaft does not occur at the time of connection, the shock that occurs at the time of connection can be suppressed. Further, since the torque of the motor is zero or substantially zero when the meshing clutch is connected, the meshing clutch is smoothly connected when the rotation speed of the motor-side meshing member and the rotation speed of the drive shaft-side meshing member are synchronized. Accordingly, the load applied to the meshing clutch is reduced, and as a result, a decrease in the durability of the meshing clutch is suppressed.

  According to the control device for a vehicle power transmission device of the invention according to claim 2, when the meshing clutch is connected while the vehicle is running, the motor drives the rotational speed of the motor-side meshing member by the motor. When the torque of the motor is reduced to zero or substantially zero after the rotational speed is increased to a rotational speed greater than the rotational speed of the side meshing member, the rotational speed of the motor side meshing member automatically decreases, and the drive shaft It corresponds to the rotational speed of the side meshing member. At this time, the meshing clutch is given a predetermined pressing force that biases the coupling member for meshing with the motor-side meshing member and the drive shaft-side meshing member toward the clutch connection side. When the two coincide, the meshing clutch is smoothly connected. Accordingly, as the load applied to the meshing clutch is suppressed, the decrease in the durability of the meshing clutch is suppressed. Further, since the torque of the electric motor is connected in a state of zero to substantially zero, the shock that occurs when the meshing clutch is connected is also suppressed. Accordingly, the meshing clutch can be smoothly connected without performing complicated rotation control of the electric motor, and a shock at the time of engagement of the meshing clutch can be suppressed.

  According to the control device for a vehicle power transmission device according to the third aspect of the invention, the time point at which the rotational speed of the electric motor is increased becomes earlier as the rate of change of the vehicle speed increases. In this way, as the rate of change of the vehicle speed increases, the change in the rotational speed of the drive shaft side meshing member also increases accordingly, so that it is necessary to start the control quickly. By increasing the time at which the rotational speed is increased, control delay can be prevented as the rotational speed of the motor-side meshing member is rapidly increased.

  According to the control device for a vehicle power transmission device of the invention according to claim 4, the rotational speed change rate when the rotational speed of the electric motor is raised increases as the vehicle speed change rate increases. In this way, as the rate of change of the vehicle speed increases, the change in the rotational speed of the drive shaft side meshing member also increases accordingly, so it is necessary to start the control quickly. By increasing the speed change rate, it is possible to prevent a delay in control as the rotational speed of the motor-side meshing member is quickly increased.

  According to the control device for a vehicle power transmission device of the invention according to claim 5, the first rotational speed in which the rotational speed of the motor-side meshing member by the electric motor is larger than the rotational speed of the drive shaft-side meshing member. When the torque of the motor is zero or substantially zero, the first rotation speed is maintained until the torque of the motor becomes zero or substantially zero. The rotation speed can be reduced from the state of the first rotation speed.

  According to the control device for a vehicle power transmission device of the sixth aspect of the invention, the second rotational speed at which the torque of the electric motor is zero to substantially zero increases as the change rate of the vehicle speed increases. Is set. In this way, for example, when the rate of change of the vehicle speed increases, the rotational speed of the drive shaft side meshing member decreases correspondingly. Torque is set to zero or substantially zero. That is, as the rotation speed of the motor side meshing member starts to decrease from a state where the rotation speed of the drive shaft side meshing member is high, the rotation speed of the motor side meshing member and the rotation speed of the drive shaft side meshing member are optimally rotated. Can be synchronized.

  Further, according to the control device for a vehicle power transmission device of the seventh aspect of the invention, since the engagement / disengagement of the meshing clutch is switched via the actuator, the pressing force acting on the side where the meshing clutch is engaged by the actuator. Is granted. Further, since the meshing clutch is connected even when the pressing force is small when the rotation is synchronized, the actuator can be downsized.

  According to the control device for a vehicle power transmission device of the eighth aspect of the invention, since the meshing clutch is a meshing clutch provided with a synchronization mechanism, the rotation synchronization of the meshing clutch is executed more smoothly.

1 is a skeleton diagram illustrating a configuration of a vehicle power transmission device to which the present invention is applied. It is a functional block diagram explaining the principal part of the control function of the electronic control apparatus of FIG. It is an example of the relationship map which shows the relationship between the change rate of a vehicle speed, and 2nd rotation speed. It is an example of the relationship map which shows the relationship between the change rate of a vehicle speed, and the start time which raises the rotational speed of an electric motor. It is an example of the relationship map which shows the relationship between the change rate of a vehicle speed, and the raise rate of the rotational speed of an electric motor. FIG. 2 illustrates a control operation of the electronic control unit of FIG. 2, that is, a control operation that can suppress a shock that occurs when the synchro clutch is connected during travel and can suppress a decrease in durability of the synchro clutch. It is a flowchart of. It is a time chart which shows the action | operation based on the control action shown by the flowchart of FIG.

  Here, preferably, in the power transmission device for a vehicle, a plurality of gear stages (shift stages) are alternatively achieved by selectively connecting rotating elements of a plurality of sets of planetary gear devices by an engagement device. For example, various planetary gear type automatic transmissions having four forward speeds, five forward speeds, six forward speeds, and more, and a plurality of pairs of gear speed gears that are always meshed with each other are provided between two shafts. A synchronous mesh type parallel twin-shaft transmission or a synchronous mesh type parallel twin-shaft transmission, in which one of the pair of shift gears is selectively transmitted by a synchronizer, but has two input shafts. A so-called DCT (Dual Clutch Transmission), which is a type of transmission in which clutches are connected to the input shafts of each system and further connected to even and odd stages, respectively, and the effective diameter of a transmission belt that functions as a power transmission member is variable. A pair of variable pulleys A so-called belt-type continuously variable transmission in which the gear ratio is continuously and continuously changed, or a pair of cones rotated around a common axis and a plurality of rotation centers that can rotate around the axis A so-called traction-type transmission in which the speed ratio is variable by changing the crossing angle between the rotation center of the roller and the shaft center by narrowing the pressure between the pair of cones. ing.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a skeleton diagram illustrating the configuration of a vehicle power transmission device 10 to which the present invention is applied. In FIG. 1, a vehicle power transmission device 10 is, for example, a front engine front wheel drive type (FF) type power transmission device, and includes a torque converter 14 coupled to an engine 12 functioning as a main drive source, and a torque converter 14. A front gear differential gear device 24 that also functions as a final reduction gear including an automatic transmission 18 connected to a turbine shaft 16 as an output shaft of the motor, a ring gear 22 that meshes with an output gear 20 of the automatic transmission 18, and a front wheel. A pair of front wheel axles 26L, 26R connected to the differential gear device 24 and a pair of front wheels 28L, 28R connected to the pair of front wheel axles 26L, 26R are provided. Further, the vehicle power transmission device 10 meshes with an electric motor 30 as a sub drive source, a motor drive gear 32 that also functions as an output shaft of the electric motor, an idler gear 34 that meshes with the motor drive gear 32, and an idler gear 34. In addition, a driven gear 38 disposed so as to be relatively rotatable around the axis of the countershaft 36, a final drive gear 40 fixed to the countershaft 36 and rotating integrally with the countershaft 36, an electric motor 30, and a counter A synchro clutch 42 is provided for intermittently connecting a power transmission path to the shaft 36.

  The engine 12 is, for example, an internal combustion engine such as a gasoline engine or a diesel engine that generates a driving force by combustion of fuel injected in a cylinder. Further, the torque converter 14 is fixed to a non-rotating member via a one-way clutch, for example, a pump impeller connected to a crankshaft of the engine 12, a turbine impeller connected to an input shaft of the automatic transmission 18, and the like. A hydrodynamic power transmission device that transmits power between the pump impeller and the turbine impeller via a fluid. The automatic transmission 18 includes a plurality of friction engagement elements, for example, and selectively inputs a plurality of transmission ratios according to a combination of engagement or release of the friction engagement elements and is input from the input shaft. It is an automatic transmission that shifts and outputs the driving force. The front wheel differential gear device 24 is a known differential mechanism that imparts differential rotation to the left and right front wheel axles 26 in accordance with the traveling state of the vehicle. With the configuration described above, the power of the engine 12 is transmitted to the left and right front wheels 28 via the torque converter 14, the automatic transmission 18, the front wheel differential gear device 24, and the front wheel axle 26.

  The synchro clutch 42 corresponding to the meshing clutch of the present invention is a meshing clutch provided with a known synchronization mechanism (synchronizing mechanism), and a clutch gear 46 driven by the electric motor 30 and a clutch hub 46 connected to the counter shaft 36. Are connected to each other or released from each other. The synchro clutch 42 is provided with a clutch hub 46 that is not rotatable relative to the countershaft 36, and is spline-fitted to the clutch hub 46 so that it cannot rotate relative to the clutch hub 46. A cylindrical sleeve 48 that is movable in the center direction and a driven gear 38 that is formed with outer peripheral teeth that can mesh with inner peripheral teeth formed on the inner peripheral surface of the sleeve 48 cannot be relatively rotated. A fixed clutch gear 50 and a synchronizer ring 52 that prevents the sleeve 48 from moving in the axial direction toward the clutch gear 50 when the rotation of the sleeve 48 and the clutch gear 50 is asynchronous. Yes. The clutch gear 50 corresponds to the motor-side meshing member driven by the motor of the present invention, the counter shaft 36 corresponds to the drive shaft of the present invention, and the clutch hub 46 corresponds to the drive shaft-side meshing member of the present invention. The sleeve 48 corresponds to the connecting member of the present invention.

  In the synchro clutch 42 of FIG. 1, the upper side of the counter shaft 36 shows a state where the synchro clutch 42 is disconnected. At this time, the sleeve 48 does not mesh with the clutch gear 50, and the clutch hub 46 and the clutch gear 50 are released, so that the connection between the counter shaft 36 and the driven gear 38 is cut, and the power of the motor 30 is supplied to the counter shaft 36. Not transmitted to. That is, the power transmission path between the electric motor 30 and the counter shaft 36 is interrupted.

  On the other hand, in the synchro clutch 42 of FIG. 1, the lower side of the counter shaft 36 shows a state where the synchro clutch 42 is connected. When the sleeve 48 is moved toward the driven gear 38 in the axial direction, the cone portion formed on the synchronizer ring 52 is pressed against the cone portion formed on the clutch gear 50, thereby causing friction between them. And the differential rotation between the clutch hub 46 and the clutch gear 50 gradually decreases. When the differential rotation between the clutch hub 46 and the clutch gear 50 is eliminated, the sleeve 48 is further moved to the driven gear 38 side, and the inner peripheral teeth of the sleeve 48 are engaged with the outer peripheral teeth of the clutch gear 50. Thus, the clutch hub 46 and the clutch gear 50 are connected, and a power transmission path between the electric motor 30 and the counter shaft 36 is formed.

  The synchro clutch 42 is switched between intermittent states via an actuator 54. The actuator 54 is constituted by an electric motor, for example, and moves a shift fork shaft 60 parallel to the axis of the counter shaft 36 via the worm gear 58 in the axial direction. A shift fork 62 that is engaged with a sleeve 48 of the synchro clutch 42 so as to be relatively rotatable is fixed to an end portion of the shift fork shaft 60. Therefore, when the actuator 54 is driven, the shift fork shaft 60 is moved in the axial direction and the position of the sleeve 48 in the axial direction is moved, so that the intermittent state of the synchro clutch 42 is switched. The actuator 54 only needs to be configured to move the shift fork shaft 60 in the axial direction. In addition to the electric motor, the actuator 54 may be configured to move the shift fork shaft 60 in the axial direction by an electromagnetic solenoid. I do not care. Further, the shift fork shaft 60 may be moved in the axial direction by a hydraulic actuator.

  In the vehicle power transmission device 10 configured as described above, in the high-speed traveling state, the vehicle V is traveled solely by the driving force of the engine 12, and the electric motor 30 is stopped. At this time, in order to eliminate the loss due to dragging of the electric motor 30, the synchro clutch 42 is disconnected. On the other hand, when the vehicle speed V of the vehicle decreases and becomes equal to or lower than a predetermined vehicle speed Vcr, the traveling by the engine 12 is stopped and the traveling by the electric motor 30 is switched. Specifically, when the synchro clutch 42 is connected, a power transmission path between the electric motor 30 and the front wheel 28 is formed, and the driving force of the electric motor 30 is transmitted to the front wheel 28.

  Here, when the vehicle speed V becomes equal to or lower than the predetermined vehicle speed Vcr, the synchro clutch 42 is switched from the disconnected state to the connected state during traveling. Conventionally, when the synchro clutch 42 is connected, the rotational speed control by the electric motor 30 is conventionally performed. Has been implemented. Specifically, the rotational speed Nm of the electric motor 30 is controlled so that the differential rotation between the rotational speed of the driven gear 38, that is, the rotational speed of the clutch gear 50 and the rotational speed of the clutch hub 46 (that is, the counter shaft 36) is reduced. It was. At this time, since the synchro clutch 42 is connected in a state in which the rotational speed control of the electric motor 30 is performed, the torque Tm of the electric motor 30 is transmitted to the front wheels 28, and when the clutch is connected, the vehicle occupant is pushed or pulled in. There was a shocking problem. In addition, it is difficult to sufficiently reduce the differential rotation by controlling the rotational speed by the electric motor 30. By connecting the synchro clutch 42 forcibly with the differential rotation, the load on the synchro clutch 42 increases. There is a problem that the durability of the synchro clutch 42 is lowered. On the other hand, in the present embodiment, by performing the control described below, it is possible to suppress a shock when the synchro clutch 42 is connected and to suppress a load applied to the synchro clutch 42.

  Returning to FIG. 1, the vehicle is provided with an electronic control device 80 including a control device for switching, for example, an engine running state by the engine 12 and an electric running state by the electric motor 30. The electronic control unit 80 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and follows a program stored in the ROM in advance. By performing signal processing, output control of the engine 12, shift control of the automatic transmission 12, and intermittent control of the sync clutch 42 are executed.

  The electronic control unit 80 includes, for example, a signal indicating the engine rotational speed Ne detected by the engine rotational speed sensor 82, and the output shaft rotational speed Nout of the output gear 20 of the automatic transmission 18 detected by the output shaft rotational speed sensor 84. A signal representing the corresponding vehicle speed V, a signal representing the motor rotation speed Nm of the electric motor 30 detected by a resolver 86 built in the electric motor 30, and the like are supplied.

  Further, the electronic control unit 80 receives, for example, an engine output control command signal Se for output control of the engine 12, a shift control command signal St for shift control of the automatic transmission 18, and the actuator 54 via the shift fork shaft 60. Then, a clutch on / off command signal Sc for switching on / off of the synchro clutch 42, a rotation command signal Sm for controlling the rotation state of the electric motor 30, and the like are output.

  FIG. 2 is a functional block diagram illustrating the main part of the control function of the electronic control unit 80. In FIG. 2, a portion indicated by a broken line corresponds to the electronic control device 80. In FIG. 2, the clutch switching determination unit 88 determines whether or not to switch the synchro clutch 42 from the disconnected state to the connected state. Specifically, the clutch switching determination unit 88 detects the vehicle speed V detected based on the output shaft rotational speed sensor 84, and if the detected vehicle speed V is equal to or lower than a preset vehicle speed Vcr, the synchronization is determined. It is determined that the clutch 42 is switched to the connected state. The vehicle speed Vcr is obtained by experiments and calculations, and is set to an optimal speed for switching the driving force source of the vehicle from the engine 12 to the electric motor 30.

  When the clutch switching determining means 88 determines that the synchro clutch 42 is switched to the connected state, the motor control means 90 increases the rotational speed Nm of the electric motor 30 and the rotational speed of the clutch gear 50 that is rotationally driven by the electric motor 30. N50 (rpm) is set to a state higher than the rotational speed of the counter shaft 36 serving as the drive shaft, that is, the drive shaft synchronous rotational speed Nsyn. The rotational speed N50 of the clutch gear 50 corresponds to the rotational speed of the motor side meshing member of the present invention, and the drive shaft synchronous rotational speed Nsyn corresponds to the rotational speed of the drive shaft side meshing member.

  The motor control means 90 raises the rotational speed N50 of the clutch gear 50 driven by the electric motor 30 to a preset first rotational speed Nm1 larger than the drive shaft synchronous rotational speed Nsyn, for example, the drive shaft synchronous rotational speed. The first rotation speed Nm1 is maintained for a predetermined time until Nsyn is lowered to the preset second rotation speed Nm2. When the drive shaft synchronous rotation speed Nsyn reaches the second rotation speed Nm2, the motor control unit 90 sets the torque Tm of the motor 30 to zero by setting the drive current supplied to the motor 30 to zero, and the rotation thereof. And the rotation of the clutch gear 50 driven thereby is reduced. Although it is desirable that the torque Tm of the electric motor 30 is zero, it is not necessarily completely zero. Even if a minute torque Tm is output from the electric motor 30, the rotational speed N50 of the clutch gear 50 is reduced (substantially). Zero).

  Simultaneously or substantially simultaneously with the torque Tm of the electric motor 30 being made zero, the clutch switching means 92 operates the actuator 54 to engage the clutch 48 with the sleeve 48 for engaging the clutch hub 46 and the clutch gear 50 with each other. A pressing force F urging the side is applied to the synchro clutch 42. That is, the synchronizing clutch 42 generates a pressing force F that urges the sleeve 48 in the direction in which the sleeve 48 is moved toward the clutch gear 50. The pressing force F is sufficient to allow the sleeve 48 to move in the axial direction, and does not require a large pressing force F. This is because if the rotational speed N50 of the clutch gear 50 driven by the electric motor 30 is synchronized with the drive shaft synchronous rotational speed Nsyn, the pressing force required to connect the synchro clutch 42 can be reduced.

  By controlling as described above, a shock generated when the synchro clutch 42 is connected is suppressed, and a load applied to the synchro clutch 42 is suppressed. More specifically, after the rotation speed N50 of the clutch gear 50 driven by the electric motor 30 is maintained at a first rotation speed Nm1 larger than the drive shaft synchronous rotation speed Nsyn for a predetermined time, the torque Tm of the electric motor 30 becomes zero. Then, the rotation of the electric motor 30 and the rotation of the clutch gear 50 driven by the electric motor 30 are reduced by the rotational resistance due to friction or the like. As a result, when a predetermined time elapses, the rotational speed N50 of the clutch gear 50 catches up with the drive shaft synchronous rotational speed Nsyn in the process of decreasing the rotational speed of the clutch gear 50. That is, the rotational speed N50 of the clutch gear 50 is synchronized with the drive shaft synchronous rotational speed Nsyn. At this time, the clutch switching means 92 applies a pressing force F applied in advance to the synchro clutch 42 in advance to the synchro clutch 42, so that the rotational speed N50 of the clutch gear 50 becomes the drive shaft synchronous rotational speed Nsyn. When synchronized, the synchro clutch 42 is smoothly connected with almost no resistance. Since the rotational speed N50 of the clutch gear 50 decreases at a rate of change greater than the drive shaft synchronous rotational speed Nsyn, it is synchronized with the drive shaft synchronous rotational speed Nsyn. This is because the inertia of the power transmission system from the electric motor 30 to the clutch gear 50 is very small compared to the inertia of the vehicle.

  Thus, the rotational speed N50 of the clutch gear 50 driven by the electric motor 30 decreases from the state of the first rotational speed Nm1 that is larger than the drive shaft synchronous rotational speed Nsyn. N50 is synchronized with the drive shaft synchronous rotation speed Nsyn, and the synchro clutch 42 is smoothly connected without imposing a large load on the synchro clutch 42. Further, since the torque Tm of the electric motor 30 is zero when the synchro clutch 42 is connected, a shock such as a push-out feeling or a pull-in feeling generated when the torque Tm of the electric motor 30 is transmitted to the front wheels 28. Does not occur.

  Here, predetermined values such as the first rotation speed Nm1 that is a target when the rotation speed N50 of the clutch gear 50 is increased and the second rotation speed Nm2 that is a threshold value that makes the torque Tm of the electric motor 30 zero are experimentally calculated. Is set to the optimum value obtained by. For example, when setting each of the predetermined values, a target rotational speed Nm3 at which the rotational speed N50 of the clutch gear 50 and the drive shaft synchronous rotational speed Nsyn coincide with each other when the synchro clutch 42 is connected is set as a reference value in advance. Optimum predetermined values at which the clutch 42 is connected in the vicinity of the target rotational speed Nm3 are obtained by experiments and calculations and stored.

  For example, the second rotational speed Nm2 serving as a threshold value for reducing the torque Tm of the electric motor 30 to zero is determined based on a relationship map between the change rate α of the vehicle speed V and the second rotational speed Nm2 obtained in advance through experiments and calculations. The As shown in FIG. 3, the relationship map is set so that the second rotational speed Nm2 increases as the change rate α of the vehicle speed V increases. For example, when the change rate α of the vehicle speed V is large, the time until the drive shaft synchronous rotational speed Nsyn reaches the target rotational speed Nm3 is shortened. In such a case, by setting the second rotational speed Nm2 to a large value, the torque Tm of the electric motor 30 is made zero at an early timing, that is, the rotation of the clutch gear 50 that is rotationally driven by the electric motor 30 at an early timing. Since the speed reduction starts, the rotation of the clutch gear 50 and the rotation of the counter shaft 36 coincide with each other in the vicinity of the preset target rotational speed Nm3 even when the drive shaft synchronous rotational speed Nsyn suddenly decreases. The synchro clutch 42 is connected. On the other hand, when the change rate α of the vehicle speed is small, the time until the drive shaft synchronous rotational speed Nsyn reaches the target rotational speed Nm3 becomes long. In such a case, the second rotational speed Nm2 is set to a small value, so that the rotational speed of the clutch gear 50 starts to be reduced at a late timing. In the vicinity of the target rotational speed Nm3, the rotation of the clutch gear 50 coincides with the rotation of the counter shaft 36, and the synchro clutch 42 is connected. As described above, the rate of change α of the vehicle speed V prevents the rotation of the clutch gear 50 and the rotation of the countershaft 36 from being synchronized at a rotational speed away from the target rotational speed Nm3. Note that the rate of change α of the vehicle speed V can be calculated by differentiating the vehicle speed V sequentially detected with time.

  In addition, even at the start point of increasing the rotational speed Nm of the electric motor 30, it is determined based on, for example, a relationship map between the change rate α of the vehicle speed V obtained in advance through experiments and calculations and the standby time point. In the relation map, as the rate of change α of the vehicle speed V increases, the standby time from when the switching to the engaged state of the synchro clutch 42 is determined becomes shorter, that is, the start time of increasing the rotational speed Nm of the electric motor 30 becomes earlier. Is set to Specifically, for example, the relationship map shown in FIG. 4 is obtained. In FIG. 4, the horizontal axis represents the rate of change α of the vehicle speed V, and the vertical axis represents the standby time for actually starting to increase the rotational speed Nm of the electric motor 30 after the determination that the sync clutch 42 is engaged. Show. As can be seen from FIG. 4, when the rate of change α of the vehicle speed V increases, the standby time from when the determination of switching to the engaged state of the synchro clutch 42 is made until the rotational speed Nm of the electric motor 30 is increased, that is, The starting point for starting the pulling up becomes earlier. This is because, for example, when the rate of change α of the vehicle speed V is large, the time required for the drive shaft synchronous rotational speed Nsyn to reach the rotational speed Nm3 is short, so the rotational speed N50 of the clutch gear 50 is quickly set to the first rotational speed Nm1. This is because it is necessary to pull up. On the other hand, when the rate of change α of the vehicle speed V is small, the time until the drive shaft synchronous rotational speed Nsyn reaches the rotational speed Nm3 becomes long. Therefore, the standby time until the rotational speed Nm of the electric motor 30 starts to be increased is lengthened. In other words, by setting the pulling start time late, the time to wait at the first rotation speed Nm1 after the rotation speed N50 of the clutch gear 50 is raised to the first rotation speed Nm1 is shortened, and the consumption of the motor 30 Suppress power.

  Further, the rotational speed change rate θ of the rotational speed Nm of the electric motor 30 is also determined based on, for example, a relationship map between the change rate α of the vehicle speed V and the rotational speed change rate θ obtained in advance through experiments and calculations. The relationship map is set so that the rotational speed change rate θ of the rotational speed Nm of the electric motor 30 increases as the change rate α of the vehicle speed V increases. Specifically, the relationship map shown in FIG. In FIG. 5, the horizontal axis represents the change rate α of the vehicle speed V, and the vertical axis represents the rotation speed change rate θ when the rotation speed Nm of the electric motor 30 is increased. As can be seen from FIG. 5, when the change rate α of the vehicle speed V increases, the rotation speed change rate θ of the rotation speed Nm of the electric motor 30 increases. This is because, for example, when the rate of change α of the vehicle speed V is large, the time required for the drive shaft synchronous rotational speed Nsyn to reach the rotational speed Nm3 is short, so the rotational speed N50 of the clutch gear 50 is quickly set to the first rotational speed Nm1. This is because it is necessary to pull up. On the other hand, when the rate of change α of the vehicle speed V is small, the time until the drive shaft synchronous rotational speed Nsyn reaches the rotational speed Nm3 becomes long. Therefore, the rotational speed change rate θ of the rotational speed Nm of the electric motor 30 is moderated. Thus, after the rotational speed N50 of the clutch gear 50 is raised to the first rotational speed Nm1, the waiting time at the first rotational speed Nm1 is shortened, and the power consumption of the electric motor 30 is suppressed.

  FIG. 6 shows the control operation of the electronic control unit 80, that is, the control operation that can suppress the shock that occurs when the synchro clutch 42 is connected while traveling and can suppress the decrease in the durability of the synchro clutch 42. Is repeatedly executed with an extremely short cycle time of about several milliseconds to several tens of milliseconds, for example. FIG. 7 is a time chart showing an operation state based on the control operation shown in the flowchart of FIG.

  In FIG. 6, first, in step SA1 (hereinafter, step is omitted) corresponding to the clutch switching determination means 88, the vehicle driving force source for which the vehicle speed V is set in advance is a threshold value for switching from the engine 12 to the electric motor 30 exclusively. It is determined whether or not the speed is lower than Vcr. When SA1 is negative, since the running by the engine 12 is continued, that is, the synchro clutch 42 is not connected, this routine is ended. On the other hand, when SA1 is affirmed, switching to the connected state of the synchro clutch 42 is determined, and in SA2 corresponding to the motor control means 90, the rotational speed N50 of the clutch gear 50 is preset by driving the electric motor 30. The first rotational speed Nm1 is increased.

  The time point at which the electric motor 30 starts to be raised corresponds to the time point t1 in the time chart shown in FIG. This start time t1 is determined based on, for example, a relationship map between the change rate α of the vehicle speed V and the standby time shown in FIG. For example, when the change rate α of the vehicle speed V is large, the time from when the determination to connect the synchro clutch 42 is made to when the rotation speed Nm of the electric motor 30 is actually started to be increased is set short. Similarly, the rotational speed change rate θ when the rotational speed Nm of the electric motor 30 is raised is similarly, for example, a relationship map between the change rate α of the vehicle speed V and the rotational speed change rate θ shown in FIG. To be determined.

  Next, at SA3 corresponding to the motor control means 90, it is determined whether or not the rotational speed N50 of the clutch gear 50 has reached a preset first rotational speed Nm1. If SA3 is negative, the process returns to SA2 and the rotation speed of the electric motor 30 continues to increase. This SA2 step corresponds to the time point t1 to the time point t2 in the time chart of FIG. On the other hand, when SA3 is affirmed, it is determined in SA4 corresponding to the motor control means 90 whether or not the drive shaft synchronous rotational speed Nsyn has decreased to a preset second rotational speed Nm2. The second rotational speed Nm2 is determined based on, for example, a relationship map between the change rate α of the vehicle speed V and the second rotational speed Nm2 as shown in FIG. When SA4 is negative, the rotational speed N50 of the clutch gear 50 is maintained at the first rotational speed Nm1 at SA5 corresponding to the motor control means 90. This step of SA5 corresponds to the time t2 to the time t3 in the time chart of FIG. From the time point t2 to the time point t3, the torque Tm of the electric motor 30 is controlled at a torque value that is low enough to maintain the rotational speed N50 of the clutch gear 50 at the first rotational speed Nm1.

  On the other hand, when SA4 is affirmed, in SA6 corresponding to the motor control means 90, the drive current of the electric motor 30 is made zero, so that the torque Tm of the electric motor 30 is made zero. The time when the torque Tm of the electric motor 30 is made zero corresponds to the time t3 in the time chart of FIG. Since the torque Tm of the electric motor 30 is made zero at the time point t3, the rotational speed N50 of the clutch gear 50 is decreased after the time point t3. The inertia of the power transmission system that constitutes the power transmission path from the clutch gear 50 to the electric motor 30 is sufficiently smaller than the inertia of the vehicle, so that when the torque Tm of the electric motor 30 becomes zero, the rotational speed of the clutch gear 50 N50 decreases at a rate of change greater than the drive shaft synchronous rotation speed Nsyn. Next, in SA7 corresponding to the clutch switching means 92, the actuator 54 is operated to generate a pressing force F that biases the sleeve 48 of the synchro clutch 42 toward the clutch connection side. Step SA7 corresponds to the time point t3 to the time point t4 in the time chart of FIG. Then, in SA8 corresponding to the clutch switching means 92, the synchro clutch 42 is smoothly connected when the rotational speed N50 of the clutch gear 50 is synchronized with the drive shaft synchronous rotational speed Nsyn (near the rotational speed Nm3). This step SA8 corresponds to time t4 in the time chart of FIG. At time t4, since the torque Tm of the electric motor 30 is zero, it is possible to prevent the vehicle occupant from being given a shock such as a feeling of pushing or being pulled when the synchro clutch 42 is connected.

  As described above, according to the present embodiment, the connection of the synchro clutch 42 while the vehicle is running is performed in a state where the torque Tm of the electric motor 30 is zero. As the torque transmission of the electric motor 30 does not occur, the shock that occurs when the synchro clutch is engaged can be suppressed. Since the torque Tm of the electric motor 30 is zero when the synchro clutch is engaged, the synchro clutch 42 is synchronized with the rotation speed N50 of the clutch gear 50 and the drive shaft synchronization rotation speed Nsyn that is the rotation speed of the clutch hub 46. Is smoothly connected, the load applied to the synchro clutch 42 is reduced, and as a result, a decrease in durability of the synchro clutch 42 is suppressed.

  Further, according to the present embodiment, when the synchro clutch 42 is connected while the vehicle is running, the rotational speed N50 of the clutch gear 50 by the electric motor 30 is the rotational speed of the clutch hub 46 connected to the counter shaft 36. When the torque Tm of the electric motor 30 is reduced to zero after the first rotational speed Nm1 higher than the drive shaft synchronous rotational speed Nsyn is increased, the rotational speed N50 of the clutch gear 50 is automatically reduced. This corresponds to the drive shaft synchronous rotation speed Nsyn. At this time, the synchro clutch 42 is given a predetermined pressing force F that biases the sleeve 48 for meshing with the clutch gear 50 and the clutch hub 46 toward the clutch connection side. At the time of coincidence (during rotation synchronization), the synchro clutch 42 is smoothly connected. As a result, as the load applied to the synchro clutch 42 is suppressed, a decrease in the durability of the synchro clutch 42 is suppressed. In addition, since the torque Tm of the electric motor 30 is connected in a zero state, a shock that occurs when the synchro clutch is engaged is also suppressed. Therefore, the synchro clutch 42 can be smoothly connected without performing complicated rotation control of the electric motor 30, and a shock at the time of connecting the synchro clutch 42 can be suppressed.

  Further, according to the present embodiment, the time point at which the rotational speed Nm of the electric motor 30 is increased becomes earlier as the change rate α of the vehicle speed V increases. In this way, as the rate of change α of the vehicle speed V increases, the change (decrease) in the drive shaft synchronous rotational speed Nsyn also increases accordingly, so that it is necessary to start the control quickly. By increasing the time point at which the rotational speed Nm of the electric motor 30 is increased, control delay can be prevented as the rotational speed N50 of the clutch gear 50 is rapidly increased.

  Further, according to this embodiment, the rotational speed change rate θ when the rotational speed Nm of the electric motor 30 is increased increases as the change rate α of the vehicle speed V increases. In this way, for example, if the rate of change α of the vehicle speed V increases, the change (decrease) in the drive shaft synchronous rotation speed Nsyn also increases accordingly, so that it is necessary to start the control quickly. As the rotational speed change rate θ of the rotational speed Nm of the electric motor 30 increases, the control delay can be prevented as the rotational speed N50 of the clutch gear 50 is quickly raised to the first rotational speed Nm1.

  Further, according to this embodiment, when the rotational speed N50 of the clutch gear 50 that is rotationally driven by the electric motor 30 is increased to the first rotational speed Nm1 that is larger than the drive shaft synchronous rotational speed Nsyn, the torque Tm of the electric motor 30 is increased. Since it is maintained at the first rotation speed Nm1 until it becomes zero or substantially zero, the rotation speed N50 of the clutch gear 50 is changed to the first rotation when the torque Tm of the electric motor 30 is zero or substantially zero. The speed can be lowered from the state of Nm1.

  Further, according to the present embodiment, the second rotational speed Nm2 at which the torque Tm of the electric motor 30 is zero to substantially zero is set to a larger value as the change rate α of the vehicle speed V increases. In this way, for example, when the rate of change α of the vehicle speed V increases, the drive shaft synchronous rotational speed Nsyn decreases accordingly, but the torque of the electric motor 30 is increased from the state where the drive shaft synchronous rotational speed Nsyn is high. Tm is set to zero or substantially zero. That is, the rotation speed N50 of the clutch gear 50 and the drive shaft synchronization rotation speed Nsyn are synchronized at a low rotation speed as the decrease in the rotation speed N50 of the clutch gear 50 starts from a state where the drive shaft synchronization rotation speed Nsyn is high. And can be synchronized in the vicinity of the target rotational speed Nm3.

  Further, according to the present embodiment, since the intermittent state of the synchro clutch 42 is switched via the actuator 54, a pressing force F acting on the side to which the synchro clutch 42 is connected is applied by the actuator 54. In addition, since the synchro clutch 42 is connected even with a small pressing force F when the rotation is synchronized, the actuator 54 can be downsized.

  Further, according to the present embodiment, since the synchro clutch 42 is a meshing clutch provided with a synchronization mechanism, the rotation synchronization of the synchro clutch 42 is executed more smoothly.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

  For example, in the above-described embodiment, the timing at which the torque Tm of the electric motor 30 is made zero is based on the value of the drive shaft synchronous rotational speed Nsyn, such as when the drive shaft synchronous rotational speed Nsyn reaches the second rotational speed Nm2. However, the control may be performed by timer control based on the time point when the synchronization of the sync clutch 42 is determined. Also in this case, for example, the time point at which the rotational speed Nm of the electric motor 30 is increased or the time point at which the torque Tm of the electric motor 30 is zero is set based on a relation map based on the rate of change α of the vehicle speed V obtained in advance through experiments and calculations. Is done.

  In the above-described embodiment, the vehicle power transmission device 10 is a front engine front wheel drive (FF) type power transmission device. However, the present invention is not limited to this, for example, the front engine rear wheel drive. Other types of power transmission devices such as the (FR) type, the rear engine rear wheel drive (RR) type, and the four wheel drive (4WD) type can be applied within a consistent range.

  In the above-described embodiment, the vehicle power transmission device 10 includes the stepped automatic transmission 18, but other than that, for example, a belt-type continuously variable transmission or a synchronous mesh type parallel twin-shaft type A configuration including a transmission of another type such as a transmission may be used. Further, the present invention can be applied even to a configuration that does not include a transmission.

  In the above-described embodiment, the synchro clutch 42 having the synchronization mechanism is used. However, the present invention does not necessarily include the synchronization mechanism, for example, a meshing clutch having no synchronization mechanism, specifically, a dog clutch. A tooth clutch, a gear clutch, a spline clutch, or the like may be used.

  In the above-described embodiment, the actuator 54 is configured by an electric motor and is configured to be able to move the shift fork shaft 60 in the axial direction via the worm gear 58. However, the actuator 54 is not necessarily limited to the above configuration. Not. For example, the shift fork shaft 60 may be moved in the axial direction using an electromagnetic solenoid, or the shift fork shaft 60 may be moved in the axial direction by hydraulic pressure.

  In the above-described embodiment, the torque Tm of the electric motor 30 is zero. However, it is not necessarily completely zero, and the rotational speed N50 of the clutch gear 50 decreases even if the torque Tm is output from the electric motor 30. Any value of about zero is acceptable.

  Further, in the above-described embodiment, the starting time point for increasing the rotational speed of the electric motor 30 and the rotational speed change rate θ are set according to the rate of change of the vehicle speed V, but the drive shaft synchronous rotation that has a one-to-one relationship with the vehicle speed V Based on the rate of change of the speed Nsyn, a start time point at which the rotational speed of the electric motor 30 is increased, a rotational speed change rate θ, and a time point at which the torque Tm of the electric motor 30 is made zero may be set.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

10: Power transmission device for vehicle 30: Electric motor 36: Counter shaft (drive shaft)
42: Synchro clutch (meshing clutch)
46: Clutch hub (drive shaft side engagement member)
48: Sleeve (connecting member)
50: Clutch gear (motor side meshing member)
54: Actuator 80: Electronic control device (control device)
Nm: Rotational speed of the motor N50: Rotational speed of the clutch gear (rotational speed of the motor-side meshing member)
Nm1: First rotation speed Nm2: Second rotation speed Nsyn: Drive shaft synchronous rotation speed (rotation speed of drive shaft side meshing member)
Tm: Motor torque F: Pushing force α: Rate of change in vehicle speed θ: Rate of change in rotation speed of motor

Claims (8)

The power transmission path between the electric motor and the drive shaft is connected to or released from the motor side meshing member driven by the motor and the drive shaft side meshing member connected to the drive shaft. A control device for a vehicle power transmission device having a meshing clutch to be intermittently engaged,
A control device for a vehicle power transmission device, wherein the engagement of the meshing clutch while the vehicle is running is performed in a state where the torque of the electric motor is zero or substantially zero.   When the meshing clutch is connected while the vehicle is running, the motor increases the rotational speed of the motor-side meshing member to a rotational speed larger than the rotational speed of the drive shaft-side meshing member, and then the torque of the motor is increased. In a state of zero or substantially zero, a predetermined pressing force is applied to the meshing clutch to urge the coupling member to mesh with the motor side meshing member and the drive shaft side meshing member of the meshing clutch toward the clutch connection side. The control device for a vehicle power transmission device according to claim 1.   3. The control device for a vehicle power transmission device according to claim 2, wherein the time point at which the rotational speed of the electric motor is increased is increased as the rate of change in vehicle speed increases.   4. The control device for a vehicle power transmission device according to claim 2, wherein a rate of change in rotation speed when the rotation speed of the electric motor is increased increases as the rate of change in vehicle speed increases. 5.   When the rotation speed of the motor-side meshing member by the motor is increased to a first rotation speed that is greater than the rotation speed of the drive shaft-side meshing member, the torque of the motor is reduced from zero to substantially zero. The control device for a vehicle power transmission device according to any one of claims 2 to 4, wherein the control device is maintained at the first rotation speed.   The torque of the electric motor is zero or substantially zero when the rotational speed of the drive shaft side meshing member reaches a preset second rotational speed lower than the first rotational speed, 6. The control device for a vehicle power transmission device according to claim 2, wherein the second rotation speed is set to a larger value as the rate of change of the vehicle speed increases.   The control device for a vehicle power transmission device according to any one of claims 1 to 6, wherein the engagement / disengagement of the meshing clutch is switched via an actuator.   The control device for a vehicle power transmission device according to any one of claims 1 to 7, wherein the meshing clutch is a meshing clutch provided with a synchronization mechanism.

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