JP6081430B2 - Shift control device - Google Patents

Description

  The present invention provides a transmission for a transmission having a first input shaft for odd-numbered gears and a second input shaft for even-numbered gears to which power from a drive source is transmitted via the first clutch and the second clutch, respectively. The present invention relates to a control device.

  2. Description of the Related Art Conventionally, a so-called dual clutch type having a first input shaft for odd-numbered gears and a second input shaft for even-numbered gears, in which power from a drive source is transmitted through a first clutch and a second clutch, respectively. A transmission is known (see, for example, Patent Document 1). In such a transmission, the first clutch and the first clutch are configured so that the power from the drive source is transmitted to the output shaft via the first drive gear on the first input shaft or the second drive gear on the second input shaft. Two clutches are controlled.

  Generally, in a transmission for a vehicle, when the vehicle on which the transmission is mounted is decelerated, control for performing a downshift is performed in preparation for reacceleration. At that time, in the case of a dual clutch transmission, a pre-shift is prepared in advance to prepare the gear of the next shift stage that is the shift destination, and then the clutch for transmitting power is connected between the first clutch and the second clutch. Shifting down is performed by switching at.

  At the time of the downshift, a shift in the first shift mode (hereinafter referred to as “first mode shift”) is usually performed in which the clutch is switched while maintaining transmission of the driving force. In addition, according to the setting, the second shift mode in which both the first clutch and the second clutch are released and the pre-shift and the engine speed are adjusted and then the first clutch or the second clutch is shifted to the transmission state. It is also possible to use a shift (hereinafter referred to as “second mode shift”).

JP2013-87800A

  In the case of the first mode shift, transmission of the engine brake driving force is not interrupted, so that stable deceleration is ensured. However, it takes a long time to shift down. Further, the shift is limited to the case of shifting from the odd-numbered stage to the even-numbered stage or vice versa, and the shift from the odd-numbered stage to the odd-numbered stage or from the even-numbered stage to the even-numbered stage cannot be performed directly.

  On the other hand, in the case of the second mode shift, not only the shift between the odd-numbered stage and the even-numbered stage but also the shift from the odd-numbered stage to the odd-numbered stage or from the even-numbered stage to the even-numbered stage is possible. As a result, downshifting for a plurality of stages is possible with a single downshifting operation. Further, since the engine speed is adjusted immediately with both the first and second clutches in the released state, the downshift can be performed in a shorter time than in the case of the first mode shift.

  However, since the transmission of power by the engine brake is interrupted while both the first and second clutches are released, the vehicle behavior is affected. Further, when the rotational difference of the clutch in the transmission state is small, fine adjustment of the engine speed is not easy, so when the first or second clutch is shifted to the transmission state, a difference occurs in the deceleration, This may give a sense of discomfort to the driver of the vehicle as a shock or acceleration.

  An object of the present invention is to provide a transmission control device for a transmission capable of improving drivability during deceleration using the advantages of both the first mode shift and the second mode shift in consideration of the characteristics of both. It is in.

  The transmission control device of the present invention includes a first input shaft, a second input shaft, a first output shaft, a second output shaft, a transmission state in which power from a drive source is transmitted to the first input shaft, and this transmission. A first clutch that can be switched to a disengaged state; a transmission state that transmits power from the drive source to the second input shaft; and a second clutch that can be switched to a disengaged state that disengages this transmission. A plurality of first drive gears for odd-numbered gears rotatably or fixedly supported on the input shaft, and for even-numbered gears rotatably or fixedly supported on the second input shaft A plurality of second drive gears, a plurality of first driven gears fixedly or rotatably supported on the first output shaft and meshing with the first drive gear, and fixed on the second output shaft Or a plurality of second driven gears rotatably supported and meshing with the second drive gear; Of the first drive gear, the second drive gear, the first driven gear, and the second driven gear, those that are rotatably supported are the first input shaft that supports the first input shaft, the first driven gear, In a vehicle transmission including a two-input shaft, the first output shaft, or a meshing mechanism connected to the second output shaft, the first drive corresponding to the selected gear position is driven by power from the drive source. The first clutch, the second clutch, and the first and second driven gears, or the second driving gear and the second driven gear, and the first output shaft or the second output shaft. A shift control device for controlling the meshing mechanism, wherein the first clutch and the second clutch are controlled as a control mode when shifting between the odd-numbered shift stage and the even-numbered shift stage when the vehicle is decelerated. Braking force or deceleration is less than the first threshold A first control mode for transitioning the second clutch or the first clutch from the disengaged state to the disengaged state in parallel with the transition of the first clutch or the second clutch from the transmission state to the disengaged state; When the braking force or deceleration of the vehicle is greater than or equal to the first threshold, the first clutch or the second clutch is shifted from the transmission state to the released state, and after the transition is completed, the second clutch or the second clutch And a second control mode in which one clutch is changed from the disengaged state to the transmitting state.

  In the present invention, at the time of shifting, the first driving gear, the second driving gear, the first driven gear, or the second driven gear corresponding to the shift speed of the shift destination, which is rotatably supported in advance, , The corresponding first input shaft, second input shaft, first output shaft, and second output shaft are connected by a meshing mechanism. After that, for example, one of the first clutch and the second clutch that is in the transmission state is set to the open state, and the one that is in the open state is set to the transmission state, and the shift is completed.

  As the control mode of the first clutch and the second clutch at the time of shifting, the above-described first control mode or the above-described second control mode is executed when the vehicle is decelerated. The first control mode corresponds to a control mode when performing a conventional first mode shift, and the second control mode corresponds to a control mode when performing a conventional second mode shift.

  Therefore, when the first control mode is executed, power transmission by the engine brake is not interrupted, so that stable deceleration is ensured, but a certain amount of time is required for downshifting. On the other hand, when the second control mode is executed, the downshift can be performed in a short time, but the power transmission by the engine brake is interrupted while both the first and second clutches are released.

  In this regard, in the present invention, when the braking force or deceleration of the vehicle is smaller than the first threshold value, the first control mode is executed, so that stable deceleration is ensured. In this case, since it is not necessary to perform the downshift quickly, it takes no long time for the downshift to take some time in the first control mode. Here, the first threshold value is a value of braking force or deceleration in a state where priority is given to shortening the time required for shifting rather than preventing transmission of power during shifting.

  On the other hand, when the braking force or deceleration of the vehicle is greater than or equal to the first threshold value, the second control mode is executed, so that the required fast downshift is realized. In this case, since the braking force or deceleration by the brake or the like is large, the influence on the behavior of the vehicle due to the release of both the first and second clutches is small.

  Therefore, according to the present invention, only the advantages can be used without being affected by the disadvantages of the first control mode and the second control mode. Thereby, the drivability at the time of deceleration of a vehicle can be improved.

  In the present invention, when the vehicle is in a constant deceleration state in which the vehicle does not transition to the acceleration state during execution of the first control mode, the braking force or deceleration of the vehicle does not exceed a second threshold value that is greater than the first threshold value. In this case, it is preferable to execute the first control mode as it is and execute the second control mode when the second threshold value is exceeded.

  That is, when the vehicle is in a constant deceleration state where the vehicle does not transition to the acceleration state and the first control mode is being executed, the first control mode remains as it is without shifting to the second control mode in which transmission of driving force is interrupted. It is desirable to execute and maintain the state as stably as possible. Therefore, in this case, as described above, even if the braking force or deceleration of the vehicle is larger than the first threshold value, the first control mode is executed as it is unless the second threshold value is exceeded. Thereby, when the first control mode is being executed and the vehicle is in a constant deceleration state, it is possible to avoid deterioration in drivability due to transition to the second control mode.

  In the present invention, when the braking force or deceleration of the vehicle is greater than the first threshold value, and the clutch differential rotation of the first clutch or the second clutch that is in the transmission state is less than or equal to a predetermined rotation number, It is preferable to shift in the first control mode.

  When the clutch differential rotation is equal to or less than the predetermined rotation number, fine adjustment of the rotation speed of the drive source is not easy, and thus a shock or a feeling of acceleration is likely to occur when setting the first clutch or the second clutch to the transmission state. . Therefore, in such a case, even if the braking force or deceleration of the vehicle is greater than the first threshold value, by performing a shift in the first control mode without executing the second control mode in which a shock is likely to occur. , It is possible to prevent such shock and acceleration.

1 is a skeleton diagram of a transmission having a power control device ECU as a shift control device according to an embodiment of the present invention. It is a flowchart which shows a part of shift control process by power control device ECU at the time of deceleration of a vehicle. FIG. 3 is a timing chart showing an example of each value when the first mode shift or the second mode shift is performed according to the process of FIG. 2, and (a) shows the timing when the brake switch is turned on; ) To (d) respectively show vehicle deceleration, brake pressure, and vehicle speed that change in response to the brake switch being turned on, and (e) shows the rotational speed of the drive source at the time of shifting. (F) and (g) show changes in the engagement torque of the first clutch C1 and the second clutch C2 when the second mode shift and the first mode shift are performed, respectively. , (H) shows a state in which the gear position is switched in accordance with the change in the engagement torque.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, a transmission 1 to which a transmission control device of an embodiment is applied is mounted on a vehicle, a transmission shaft 2 to which a driving force (output torque) of an internal combustion engine ENG as a driving source is transmitted, An output shaft 3a having an output gear 3 that outputs power to left and right front wheels as drive wheels via an outer differential gear, and a plurality of gear trains G2 to G5 having different gear ratios are provided.

  The transmission 1 also includes a first input shaft 4 that rotatably supports the drive gears G3a and G5a of the odd-numbered gear trains G3 and G5 that establish odd-numbered gears (odd gears) in the gear ratio order. And the second input shaft 5 that rotatably supports the drive gears G2a and G4a of the even-numbered gear trains G2 and G4 that establish even-numbered gears (even-numbered gears) in the gear ratio order, and the reverse gear is established. And a reverse shaft 6 that rotatably supports the reverse drive gear GRa of the reverse gear train GR that is used when the reverse drive gear GRa and the reverse driven gear GRb are used. The first input shaft 4 is disposed on the same axis as the transmission shaft 2, and the second input shaft 5 is disposed in parallel with the first input shaft 4.

  The transmission 1 meshes with an idle drive gear Gia rotatably supported by the first input shaft 4, a first idle driven gear Gib meshed with the idle drive gear Gia, and a first idle driven gear Gib. An idle gear train Gi composed of a second idle driven gear Gic fixed to the second input shaft 5 and a third idle driven gear Gid meshed with the first idle driven gear Gib and fixed to the reverse shaft 6 Prepare.

  The transmission 1 includes a first clutch C1 and a second clutch C2 that are hydraulically operated wet friction clutches. The first clutch C1 is configured to be switchable between a transmission state in which the driving force of the internal combustion engine ENG transmitted to the transmission shaft 2 is transmitted to the first input shaft 4 and an open state in which this transmission is cut off. The second clutch C2 is configured to be switchable between a transmission state in which the driving force of the internal combustion engine ENG transmitted to the transmission shaft 2 is transmitted to the second input shaft 5 and an open state in which this transmission is cut off.

  The states of both clutches C1 and C2 are switched by the hydraulic pressure supplied from the clutch control circuit 10. In addition, the clutches C1 and C2 can adjust the engagement pressure in the transmission state by adjusting the hydraulic pressure with an actuator (not shown) provided in the clutch control circuit 10 (the so-called half-clutch state can also be set). .

  Lubricating oil is supplied to the lubricating circuit 9 from the pump 8, and the lubricating circuit 9 includes an oil passage that distributes the lubricating oil to locations in the transmission 1 such as the clutches C <b> 1 and C <b> 2 that require lubrication. The pump 8 is disposed at the end opposite to the internal combustion engine ENG and coaxially with the transmission shaft 2. The pump shaft 2 a is connected to the transmission shaft 2 through the hollow first input shaft 4. Is driven by the internal combustion engine ENG.

  Like the pump 8, the lubrication circuit 9 is disposed at the end opposite to the internal combustion engine ENG and coaxially with the transmission shaft 2.

  Further, the transmission 1 is provided with a planetary gear mechanism PG that is coaxial with the transmission shaft 2 and is positioned closer to the internal combustion engine ENG than the pump 8. The planetary gear mechanism PG is configured as a single pinion type that includes a sun gear Sa, a ring gear Ra, and a carrier Ca that pivotally supports a pinion Pa that meshes with the sun gear Sa and the ring gear Ra.

  Three elements including the sun gear Sa, the carrier Ca, and the ring gear Ra of the planetary gear mechanism PG are arranged at intervals corresponding to the gear ratio in the collinear chart (the relative rotation speed of each element can be expressed by a straight line). If the first element, the second element, and the third element are respectively arranged from the sun gear Sa side (one side) in the order of arrangement, the first element is the sun gear Sa, the second element is the carrier Ca, and the third element is the ring gear Ra.

  The gear ratio of the planetary gear mechanism PG (the number of teeth of the ring gear Ra / the number of teeth of the sun gear Sa) is g, and in the collinear diagram, the distance between the sun gear Sa as the first element and the carrier Ca as the second element The ratio between the carrier Ca as the second element and the distance between the ring gear Ra as the third element is g: 1.

  The sun gear Sa as the first element is fixed to the first input shaft 4. The carrier Ca as the second element is connected to the third speed drive gear G3a of the third speed gear train G3. The ring gear Ra as the third element is fixed to the transmission case 7 so as to be releasable by a lock mechanism B1 (brake).

  The lock mechanism B1 (brake) is configured by a synchronous meshing mechanism, and is configured to be switchable between a fixed state in which the ring gear Ra (third element) is fixed to the transmission case 7 and an open state in which this fixing is released. Yes.

  In addition, the planetary gear mechanism PG is configured by a double pinion type including a sun gear, a ring gear, and a carrier that pivotally supports a pair of pinions that mesh with each other, one of which is sun gear and the other is meshed with the ring gear. May be. In this case, for example, the sun gear (first element) is fixed to the first input shaft 4, the ring gear (second element) is connected to the third speed drive gear G3a of the third speed gear train G3, and the carrier (third element) May be configured to be releasably fixed to the transmission case 7 by a lock mechanism B1 (brake).

  A hollow electric motor MG (motor / generator), which is a rotating electric machine, is disposed outward in the radial direction of the planetary gear mechanism PG. In other words, the planetary gear mechanism PG is disposed inside the hollow electric motor MG. The electric motor MG includes a stator MGa and a rotor MGb. The rotor MGb includes a rotor hub that is positioned between the pump 8 and the planetary gear mechanism PG and extends toward the transmission shaft 2 side. The rotor hub is splined to the first input shaft 4.

  The electric motor MG is controlled via a power drive unit PDU based on an instruction signal from a power control unit ECU (Electronic Control Unit), and the power control unit ECU consumes the power of the secondary battery BATT. Thus, the state is switched appropriately between a driving state in which the electric motor MG is driven and a regenerative state in which the rotational power of the rotor MGb is suppressed to generate power and the generated power is charged to the secondary battery BATT via the power drive unit PDU.

  The electric motor MG is provided with a rotation sensor MGc for detecting the rotation speed of the electric motor MG (rotation speed of the rotor MGb), and the rotation sensor MGc is configured to be able to transmit the detected rotation speed of the electric motor MG to the power control device ECU. ing.

  The power control device ECU is an electronic unit composed of a CPU, a memory, and the like, and executes a control program held in a storage unit such as a memory by the CPU, and corresponds to the transmission control device of the present invention. A signal of a shift mechanism that is switched to any one of a forward range, a neutral range, a reverse range, and a parking range by a driver's shift operation is input to the power control device ECU. The power control device ECU receives information about the acceleration (deceleration) of the vehicle, and information on the operation of a braking mechanism that brakes the wheels by a braking operation performed by the driver depressing the brake pedal. This operation information includes information about the on / off state of the brake switch and information about the braking force generated by depressing the brake pedal.

  A reverse driven gear GRb that meshes with the reverse drive gear GRa of the reverse gear train GR that is rotatably supported by the reverse shaft 6 is fixed to the first input shaft 4. The output shaft 3a that supports the output gear 3 is fixed with a second gear G2a and a driven gear Go1 that meshes with the third gear G3a. A driven gear Go2 that meshes with the fourth speed drive gear G4a and the fifth speed drive gear G5a is fixed to the output shaft 3a.

  As described above, the driven gears of the second gear train G2 and the third gear train G3 and the driven gears of the fourth gear train G4 and the fifth gear train G5 are configured by one gear Go1 and Go2, respectively. The axial length (axial dimension) of the machine 1 can be shortened, and the FF (front wheel drive) system can be mounted on a vehicle.

  The first input shaft 4 is configured by a synchronous meshing mechanism, and the third speed drive gear G3a and the first input shaft 4 are connected to each other. The fifth speed drive gear G5a and the first input shaft 4 are connected to each other. There is provided a first meshing mechanism SM1 that can be switched to any one of a neutral state in which the connection between the 5-speed side connected state, the 3-speed drive gear G3a and the 5-speed drive gear G5a and the first input shaft 4 is disconnected. .

  The second input shaft 5 is composed of a synchronous meshing mechanism, and the second speed drive gear G4a and the second input shaft 5 are connected to each other. The fourth speed drive gear G4a and the second input shaft 5 are connected to each other. There is provided a second meshing mechanism SM2 that can be switched to any one of a neutral state in which the connection between the second-speed drive gear G2a and the fourth-speed drive gear G4a and the second input shaft 5 is disconnected. .

  The reverse shaft 6 includes a third meshing mechanism SM3 that is configured by a synchronous meshing mechanism and can be switched between a coupled state in which the reverse drive gear GRa and the reverse shaft 6 are coupled and a neutral state in which the coupling is disconnected. Is provided. The first meshing mechanism SM1, the second meshing mechanism SM2, and the third meshing mechanism SM3 are controlled by the power control device ECU.

  Further, the power control device ECU controls the actuator (not shown) of the clutch control circuit 10 to adjust the hydraulic pressure to switch between the transmission state and the release state of both clutches C1 and C2.

  A parking gear Gp is coupled to the second speed drive gear G2a by spline coupling so as to be integrally rotatable so as to be aligned in the axial direction. In addition, an engaging portion LKa is provided that includes a parking pole that can be engaged with the parking gear Gp. A parking mechanism LK is configured by the parking gear Gp and the engaging portion LKa. This parking mechanism LK operates according to an instruction from the power control device ECU.

  FIG. 2 shows a part of the shift control process by the power control device ECU during deceleration. This process is repeated every predetermined short time. In this process, it is determined whether the first mode shift or the second mode shift is performed as the shift operation when the brake pedal is depressed, and the shift operation according to the determination is performed.

  That is, when the process is started, the power control device ECU first determines whether or not the brake switch is on, that is, whether or not the brake pedal is depressed (step S1). While the ON state continues, it can be determined that the vehicle is in a constant deceleration state where the vehicle does not transition to the acceleration state. If it is determined not to be in the on state, the processing in FIG.

  If it is determined that it is in the on state, it is determined whether or not the speed change operation is being performed (step S2). The speed change operation is the process of step S9 or S10. Therefore, when it is determined that the speed change operation is being performed, the process of FIG. 2 is not necessary, and the process of FIG. 2 is terminated.

  If it is determined that the speed change operation is not being performed, a target speed that is the speed to be shifted next is determined by downshifting based on the early down map during braking (step S3). The early down map during braking is a table in which the next target stage is associated with various values such as the current shift stage and the braking force by the brake. For example, when the current gear position is the fifth gear position by the gear train G5 and the brake pedal is depressed relatively strongly, the second gear speed by the gear train G2 is determined as the target gear position.

  Next, it is determined whether the last-time shift is the second mode shift or the first mode shift during the brake in which the brake switch is turned on last time and the state continues. (Steps S4 and S5). If neither the second mode shift nor the first mode shift is being performed during braking, this is the first shift during the brake, and thus the process proceeds to step S6, where the deceleration of the vehicle or the rate of change thereof is the first. It is determined whether the threshold value is 1 or more. A braking force applied to the vehicle may be used instead of the deceleration of the vehicle.

  The first threshold value is a deceleration when a priority is given to shortening the time required for the shift by the second mode shift, rather than preventing the power transmission during the shift from being interrupted by the first mode shift. It is the value of the rate of change. If it is determined that the deceleration of the vehicle or the rate of change thereof is not equal to or greater than the first threshold value, it is not necessary to shorten the time required for the shift, and therefore the shift by the first mode shift that does not interrupt power transmission during the shift is performed. (Step S9).

  If it is determined in step S6 that it is greater than or equal to the first threshold value, it is further determined whether or not the clutch differential rotation with the next target stage determined in step S3 is less than or equal to a predetermined value (step S7).

  Here, “clutch differential rotation with the next target stage” means that the rotation speed of the first clutch C1 or the second clutch C2 that is currently in the transmission state and the transmission state is shifted down to the next target stage. This is the difference from the rotation speed of the second clutch C1 or the first clutch C2. That is, it corresponds to the rotational speed of the drive source that changes during the downshift.

  If it is determined in step S7 that the clutch differential rotation is equal to or less than the predetermined value, the clutch control circuit 10 or the like is instructed to perform a shift by the first mode shift in which power transmission during the shift is not interrupted (step S9). . In this case, when the second mode shift is performed, it is difficult to adjust the rotational speed of the drive source by the clutch differential rotation while the first clutch C1 and the second clutch C2 are in the released state. This is because the shock felt by the driver when the first clutch C1 or the second clutch C2 transitions to the transmission state is conspicuous.

  In the first mode shift, first, a pre-shift for preparing a gear for the next shift stage as a shift destination is performed. For example, if the current gear is the fifth gear and the target gear is the second gear, the second meshing mechanism is used to establish the fourth gear that is the next gear after the fifth gear. SM2 is driven and controlled, and the drive gear G4a of the gear train G4 is connected to the second input shaft 5.

  Next, the first clutch C1 and the second clutch C2 are controlled in the first control mode. That is, if the next shift speed is the fourth shift speed as in the above example, the shift is from the odd speed to the even speed, and therefore the first clutch C1 is shifted from the transmission state to the disengaged state. In parallel, the second clutch C2 is shifted from the disengaged state to the transmitting state. Thereby, the first mode shift is completed.

  If it is determined in step S7 that the clutch differential rotation is not less than or equal to the predetermined value, the clutch control circuit 10 or the like is instructed to perform a second mode shift that can quickly adjust the clutch differential rotation (step S10).

  In the second mode shift, first, a pre-shift for preparing a gear for the next shift stage as a shift destination is performed. For example, if the current gear is the fifth gear and the target is the second gear, the second meshing mechanism is used to establish the fourth gear that is the gear after the fifth gear. SM2 is driven and controlled, and the drive gear G4a of the gear train G4 is connected to the second input shaft 5.

  Next, the first clutch C1 and the second clutch C2 are controlled in the second control mode. That is, if the next shift speed is the fourth speed as in the above example, the shift is from the odd speed to the even speed, so the first clutch C1 is shifted from the transmission state to the disengaged state. Is completed, the second clutch C2 is shifted from the disengaged state to the transmitting state. Thereby, the second mode shift is completed.

  On the other hand, if it is determined in the above step S4 that the previous shift during the currently continued braking is the second mode shift, the process proceeds to step S7, where the clutch differential rotation with the next target stage is performed. Unless it is determined that is less than or equal to the predetermined value, the second mode shift is performed (step S10). This is because it is preferable to follow the previous shift mode as long as there is no inconvenience, since the driver feels uncomfortable if the shift is performed in a shift mode different from the previous shift mode.

  Further, when it is determined in the above step S5 that the previous shift during the currently continued braking is the first mode shift, the vehicle deceleration or the rate of change thereof is greater than the first threshold. It is determined whether or not a large second threshold is exceeded (step S8). The second threshold is a value of the speed or the rate of change when the second mode shift is more preferable than the first mode shift performed last time during braking.

  If it is determined that the second threshold value has not been exceeded, it is preferable to follow the first mode shift performed last time during braking and not give the driver a sense of incongruity than to perform the second mode shift. Therefore, the first mode shift is performed (step S9).

  If it is determined that the second threshold value is exceeded, the process proceeds to step S7, where a second mode shift is performed unless it is determined that the clutch differential rotation with the next target stage is not more than a predetermined value. (Step S10). This is because, since the deceleration or the rate of change thereof is large, it is preferable to perform a second mode shift in which the first and second clutches C1 and C2 are not conspicuous even when they are in an open state and can be shifted quickly.

  When the instruction to perform the first mode shift in step S9 is completed and when the instruction to perform the second mode shift in step S10 is completed, the process of FIG.

  FIG. 3 shows the first mode shift (step S9) or the second mode shift according to the deceleration of the vehicle or the like when shifting down from the fourth shift stage to the second shift stage during braking according to the processing of FIG. An example of each value when (step S10) is performed is shown. FIG. 3A shows the timing when the brake switch is turned on.

  FIGS. 3B to 3D respectively show vehicle deceleration, brake pressure, and vehicle speed that change in response to the brake switch being turned on. FIG. 3E shows a change in the rotational speed of the drive source when downshifting is performed.

  FIG. 3F shows a change in engagement torque when the first clutch C1 and the second clutch C2 are controlled in the second control mode when the second mode shift is performed. FIG. 3G shows a change in engagement torque when the first clutch C1 and the second clutch C2 are controlled in the first control mode when the first mode shift is performed. FIG. 3 (h) shows a state in which the gear position is switched according to a change in the engagement torque.

  In FIGS. 3B to 3E and 3H, a change when the first mode shift is performed is indicated by a broken line, and a change when the second mode shift is performed is indicated by a solid line. 3 (f) and 3 (g), the change in the engagement torque of the first clutch C1 is indicated by a solid line, and the change in the engagement torque of the second clutch C2 is indicated by a one-dot chain line.

  When the vehicle brake switch is turned on as shown in FIG. 3A, the brake pressure shown in FIG. 3C and the vehicle speed shown in FIG. The deceleration is determined as in b). In accordance with this deceleration (steps S6 and S8 in FIG. 2), the second mode shift shown in FIG. 3 (f) or the first mode shift shown in FIG. 3 (g) is performed.

  That is, when the brake pressure in FIG. 3 (c) is large (in the case of a solid line), the vehicle speed in FIG. 3 (d) decreases rapidly and the deceleration in FIG. 3 (b) is large (step S6). The second mode shift (step S10) is performed as long as the clutch differential rotation with respect to the target stage is not less than the predetermined value (step S7).

  On the other hand, when the brake pressure in FIG. 3C is small (in the case of a broken line), the vehicle speed in FIG. 3D decreases slowly and the deceleration in FIG. 3B is small (step S6). A 1-mode shift (step S9) is performed.

  When the second mode shift is performed, as shown in FIG. 3F, the first clutch C1 and the second clutch C2 are controlled in the second control mode. That is, as shown in FIG. 3 (h), when shifting down from the fourth gear to the third gear first, the second clutch C2 is shifted from the transmission state to the released state, and after the transition is completed, Control for changing the first clutch C1 from the disengaged state to the transmitting state is performed.

  During this time, while the engagement torque from when the second clutch C2 is released to when the first clutch C1 is in the transmission state is zero, as shown in FIG. It is adjusted so as to match the gear ratio of the third gear.

  On the other hand, when the first mode shift is performed, as shown in FIG. 3G, the first clutch C1 and the second clutch C2 are controlled in the first control mode. That is, as shown in FIG. 3 (h), when shifting down from the fourth shift speed to the third shift speed first, the first clutch is set in parallel with the transition of the second clutch C2 from the transmission state to the release state. Control is performed to shift the clutch C1 from the disengaged state to the transmitting state.

  During this time, the engagement torque of the first clutch C1 and the second clutch C2 is continuous without interruption, and therefore, until the bearer of the engagement torque switches from the second clutch C2 to the first clutch C1, FIG. As in e), the rotational speed of the drive source is increased to a rotational speed that matches the gear ratio of the third gear.

  As shown in FIG. 3A, when the second mode shift is performed at the time of the downshift from the fourth shift stage to the third shift stage after the brake switch is turned on (in the determination of step S4). “Yes”), when further shifting down to the second gear, unless it is determined that the clutch differential rotation with the second gear is equal to or less than the predetermined value (“No” in step S7), FIG. ), The second mode shift is performed again.

  On the other hand, when the first mode shift is performed during the downshift from the fourth shift speed to the third shift speed after the brake switch is turned on ("Yes" in step S5), further When shifting down to the second gear position, unless the deceleration exceeds the second threshold (“No” in step S8), the first mode shift is performed again as shown in FIG.

  As described above, according to the present embodiment, when the braking force or deceleration of the vehicle is smaller than the first threshold, the first and second clutches C1 and C2 are controlled in the first control mode. Can be ensured. In this case, since it is not necessary to perform the downshift quickly, it takes no long time for the downshift to take some time in the first control mode.

  On the other hand, when the braking force or deceleration of the vehicle is greater than the first threshold value, the first and second clutches C1 and C2 are controlled in the second control mode. Can be realized. In this case, since the braking force or deceleration by the brake or the like is large, the uncomfortable feeling due to the disengagement of both the first and second clutches C1 and C2 is not noticeable and does not cause a problem.

  Therefore, only the advantages can be used without being affected by the disadvantages of the first control mode and the second control mode. Thereby, the drivability at the time of deceleration of a vehicle can be improved.

  When the first control mode is being executed (“Yes” in step S5), and the vehicle is in a constant deceleration state that does not transition to the acceleration state (“Yes” in step S1), the braking force of the vehicle Alternatively, when the deceleration does not exceed the second threshold value that is larger than the first threshold value (“No” in the determination in step S8), the first control mode is executed as it is (step S9) and the second threshold value is exceeded. In principle, the second control mode is executed except for the case where the clutch differential rotation with the next target stage is a predetermined value (step S10).

  This prevents the drivability from deteriorating by shifting to the second control mode when the first control mode is being executed, the vehicle is in a constant deceleration state, and there is little need for quick downshifting. can do.

  Further, when the braking force or deceleration of the vehicle is larger than the first threshold value, and the clutch differential rotation of the first clutch C1 or the second clutch C2 to be transmitted is equal to or less than the predetermined rotation number (determination in step S7). "Yes"), the speed is changed in the first control mode (step S9).

  As described above, when the clutch differential rotation is equal to or lower than the predetermined rotation speed, a shock or a feeling of acceleration is likely to occur when the first clutch C1 or the second clutch C2 is set to the transmission state in the second control mode. However, in such a case, since the speed is changed in the first control mode, such a shock and a feeling of acceleration can be avoided.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this. For example, instead of performing the outputs from the odd-numbered gear trains G3 and G5 and the outputs from the even-numbered gear trains G2 and G4 via the common output shaft 3a, the first output shaft and the second output shaft are separately provided. You may be made to go through.

  DESCRIPTION OF SYMBOLS 4 ... 1st input shaft, 5 ... 2nd input shaft, 3a ... Output shaft (1st output shaft, 2nd output shaft), C1 ... 1st clutch, C2 ... 2nd clutch, ECU ... Power control apparatus (shift control) Device), ENG ... drive source, G3a, G5a ... drive gear (first drive gear), G2a, G4a ... drive gear (second drive gear), Go1, Go2 ... driven gear (first driven gear, second driven gear) ), SM1... First meshing mechanism, SM2.

Claims (3)

A first input shaft, a second input shaft, a first output shaft, and a second output shaft;
A first clutch capable of switching between a transmission state in which power from a drive source is transmitted to the first input shaft and an open state in which this transmission is interrupted;
A second clutch that can be switched between a transmission state in which power from the drive source is transmitted to the second input shaft and an open state in which this transmission is interrupted;
A plurality of first drive gears for odd-numbered gears rotatably or fixedly supported on the first input shaft;
A plurality of second drive gears for even speed stages that are rotatably or fixedly supported on the second input shaft;
A plurality of first driven gears fixedly or rotatably supported on the first output shaft and meshing with the first drive gear;
A plurality of second driven gears fixedly or rotatably supported on the second output shaft and meshing with the second drive gear;
Of the first drive gear, the second drive gear, the first driven gear, and the second driven gear, those that are rotatably supported are the first input shaft, the first input shaft, In a vehicle transmission including a two-input shaft, a first output shaft, or a meshing mechanism connected to the second output shaft,
The power from the drive source passes through the first drive gear and the first driven gear, or the second drive gear and the second driven gear corresponding to the selected gear position, and then the first output shaft or the second driven gear. A shift control device for controlling the first clutch, the second clutch, and the meshing mechanism so as to transmit to two output shafts;
As a control mode of the first clutch and the second clutch when shifting between the odd-numbered gear stage and the even-numbered gear stage when the vehicle is decelerated,
When the braking force or deceleration of the vehicle is smaller than the first threshold, the second clutch or the first clutch is released in parallel with the transition of the first clutch or the second clutch from the transmission state to the release state. A first control mode for transitioning from a state to a transmission state;
When the braking force or deceleration of the vehicle is greater than or equal to the first threshold, the first clutch or the second clutch is transitioned from the transmission state to the disengaged state, and after the transition is completed, the second clutch or the first clutch And a second control mode for shifting the clutch from the disengaged state to the transmitting state.   During execution of the first control mode, when the vehicle is in a constant deceleration state that does not transition to the acceleration state, when the braking force or deceleration of the vehicle does not exceed a second threshold value that is higher than the first threshold value, The speed change control device according to claim 1, wherein the first control mode is executed as it is, and the second control mode is executed when the second threshold value is exceeded. When the braking force or deceleration of the vehicle is greater than the first threshold, and the clutch differential rotation of the first clutch or the second clutch that is in the transmission state is less than or equal to a predetermined rotation number, the first control mode The shift control device according to claim 1, wherein the shift control device shifts at a speed.

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