JP5085289B2 - Transmission control device - Google Patents

Description

  The present invention relates to a transmission control device, and more particularly to start control.

As a transmission control device, a technique described in Patent Document 1 is known. This publication discloses a twin clutch type automatic manual transmission device. When the shift lever is in the N range, the neutral state in which no power is transmitted is maintained by releasing both of the twin clutches and setting the shift actuator to the neutral position. When the shift lever is shifted from the N range to the D range (hereinafter referred to as N → D select), the 1-R shift actuator is moved, and one of the twin clutches is engaged to transmit the first speed power. I do.
JP 2007-040408 A

  In the above prior art, when the N range is selected, the driver depresses the accelerator pedal, and when N → D is selected while maintaining the accelerator depressed state, the power transmission path (starting gear stage) is not established. Since the clutch cannot be engaged, the engine speed increases during that time.

  After that, when the power transmission path is established and the clutch can be engaged, there is a problem that the difference in rotational speed between the engine rotational speed and the clutch rotational speed is large, and a large shock is generated at the time of engagement.

  The present invention has been made paying attention to the above-described problem, and an object of the present invention is to provide a transmission control device capable of stable start control even in N → D selection when the accelerator pedal is depressed.

For this purpose, the present invention determines whether or not the power transmission mechanism can transmit torque when the driver maintains the depression of the accelerator pedal and switches the range position of the transmission from the neutral range to the travel range. When it is determined that torque transmission is not possible, the power transmission mechanism is provided with an upper limit setting means for setting an upper limit for the engine torque so that the engine speed is lower than the speed corresponding to the depression of the accelerator pedal. , where the upper limit setting means, it was decided to maintain the upper limit setting until the play elimination of the friction clutch is completed.

  Therefore, by reducing the heat generation of the power transmission mechanism while suppressing the engine speed from rising, it is possible to improve the durability of the power transmission mechanism and to suppress a shock that occurs at the start of torque transmission.

  Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.

  FIG. 1 is a skeleton diagram of a twin clutch type automatic manual transmission illustrating an automatic manual transmission.

  The output shaft (crankshaft 2) of the engine 1 is connected to an automatic wet rotation clutch C1 for odd-numbered gears (first speed, third speed, fifth speed, reverse) and an even-numbered gear speed (second speed, fourth gear). (Speed, 6th speed) is connected to the common clutch drum 3 of the automatic wet rotary clutch C2.

  The twin-clutch automatic manual transmission includes a first input shaft 4 for odd-numbered gears (first speed, third speed, fifth speed, reverse) and even-numbered gear speeds (second speed, fourth speed, sixth speed). The second input shaft 5 for the speed) is provided, and the first input shaft 4 and the second input shaft 5 can be coupled to the engine output shaft 2 by the respective automatic clutches C1 and C2.

  The twin-clutch automatic manual transmission further includes an output shaft 6, which is arranged in parallel with the first input shaft 4 and the second input shaft 5, and the output shaft 6 is connected via a propeller shaft and a differential gear device (not shown). To the left and right drive wheels.

  The gear transmission mechanism of the twin clutch type automatic manual transmission will be described in detail below.

  Of the first input shaft 4 and the second input shaft 5 to which engine rotation is selectively input via the odd-numbered speed clutch C1 and the even-numbered speed clutch C2, the second input shaft 5 is hollow, and this is the first input. Although fitted on the shaft 4, the inner first input shaft 4 and the outer second input shaft 5 are rotatable concentrically with each other.

  As described above, the engine-side front ends of the first input shaft 4 and the second input shaft 5 that are rotatably fitted to each other are coupled to the clutch hubs 7 and 8 of the clutches C1 and C2, and the first input shaft 4 is connected to the second input. Projecting from the rear end of the shaft 5, the rear end portion 4a is set on the first input shaft 4, and the counter shaft 10 is arranged in parallel with the first input shaft 4, the second input shaft 5, and the output shaft 6. Provide.

  A counter gear 11 is provided at the rear end of the counter shaft 10 so as to be integrally rotatable, and an output gear 12 is provided in the same plane perpendicular to the shaft, and the output gear 12 is coupled to the output shaft 6.

  The counter gear 11 and the output gear 12 are engaged with each other to drive-couple the counter shaft 10 to the output shaft 6.

  Between the rear end portion 4a of the first input shaft 4 and the countershaft 10, the gear sets G1, G3, G5 of the odd-numbered speed stage (first speed, third speed, fifth speed) group and the gears of the reverse speed stage A set GR is provided, and these are arranged in the order of the first speed gear set G1, the reverse gear set GR, the fifth speed gear set G5, and the third speed gear set G3 from the front side close to the engine 1.

  The first speed gear set G1 includes a first speed input gear 13 formed integrally with the rear end portion 4a of the first input shaft 4, and a first speed output gear 14 rotatably provided on the countershaft 10. It is configured by meshing.

  The reverse gear set GR is meshed with the reverse input gear 15 integrally formed on the rear end portion 4a of the first input shaft 4, the reverse output gear 16 rotatably provided on the countershaft 10, and the gears 15 and 16. The gears 15 and 16 are composed of a reverse idler gear 17 that is driven and coupled in the reverse direction, and the reverse idler gear 17 is rotatably supported by a reverse idler shaft 18 that is installed in the transmission case.

  The third speed gear set G3 includes a third speed input gear 19 that is rotatably provided at the rear end 4a of the first input shaft 4, and a third speed output gear 20 that is drivingly coupled to the countershaft 10. It is configured to mesh with each other.

  The fifth speed gear set G5 includes a fifth speed input gear 31 that is rotatably provided at the rear end portion 4a of the first input shaft 4, and a fifth speed output gear 32 that is drive-coupled to the countershaft 10. It is configured by meshing with each other.

  The countershaft 10 is further provided with a first speed-reverse synchronous meshing mechanism 21 disposed between the first speed output gear 14 and the reverse output gear 16. The first speed-reverse synchronous meshing mechanism 21 causes the first speed output gear 14 to move to the countershaft 10 when the coupling sleeve 21a that rotates together with the countershaft 10 is left-shifted from the illustrated neutral position and meshed with the clutch gear 21b. It is assumed that the first speed can be selected as described later. On the other hand, when the coupling sleeve 21a is moved rightward from the illustrated neutral position and meshed with the clutch gear 21c, the reverse output gear 16 is drivingly coupled to the countershaft 10 so that the reverse can be selected as described later.

  The rear end portion 4a of the first input shaft 4 is further provided with a third-speed fifth-speed synchronous meshing mechanism 22 disposed between the third-speed input gear 19 and the fifth-speed input gear 31. When the coupling sleeve 22a that rotates together with the first input shaft 4 (rear end portion 4a) is moved to the right from the neutral position shown in FIG. A third speed input gear 19 is drivingly coupled to the first input shaft 4 so that the third speed can be selected as will be described later. On the other hand, when the coupling sleeve 22a is moved leftward from the illustrated neutral position and meshed with the clutch gear 22c, the fifth speed input gear 31 is drivingly coupled to the first input shaft 4 and the fifth speed can be selected as will be described later. It shall be

  Between the hollow second input shaft 5 and the countershaft 10, there is a gear group of the even-numbered speed (second speed, fourth speed, sixth speed) group, that is, the sixth gear sequentially from the front side close to the engine. A speed gear set G6, a second speed gear set G2, and a fourth speed gear set G4 are provided.

  The sixth speed gear set G6 is disposed at a relatively front portion of the second input shaft 5, the fourth speed gear set G4 is disposed at the rear end of the second input shaft 5, and the second speed gear set G2 is the second input. The shaft 5 is disposed at the center between these front and rear ends.

  The sixth speed gear set G6 has a sixth speed input gear 23 integrally formed on the outer periphery of the second input shaft 5 and a sixth speed output gear 24 rotatably provided on the countershaft 10 meshing with each other. Configure.

  The second speed gear set G2 is formed by meshing a second speed input gear 25 integrally formed on the outer periphery of the second input shaft 5 and a second speed output gear 26 rotatably provided on the countershaft 10. Configure.

  The fourth speed gear set G4 includes a fourth speed input gear 27 integrally formed on the outer periphery of the second input shaft 5 and a fourth speed output gear 28 that is rotatably provided on the counter shaft 10 and meshes with each other. Configure.

  Further, the countershaft 10 is provided with a synchronous meshing mechanism 29 dedicated to the sixth speed disposed between the sixth speed output gear 24 and the second speed output gear 26. In the 6-speed dedicated meshing mechanism 29, when the coupling sleeve 29a that rotates together with the countershaft 10 is moved to the left from the illustrated neutral position and meshed with the clutch gear 29b, the 6th-speed output gear 24 is driven by the countershaft 10. It is assumed that the sixth speed can be selected as described later.

  The countershaft 10 is provided with a second-speed / fourth-speed synchronous meshing mechanism 30 disposed between the second-speed output gear 26 and the fourth-speed output gear 28. The second-speed / four-speed synchronous meshing mechanism 30 is configured such that when the coupling sleeve 30a that rotates together with the countershaft 10 is moved to the left from the illustrated neutral position and meshed with the clutch gear 30b, the second-speed output gear 26 is moved to the countershaft. The second speed can be selected as will be described later. On the other hand, when the coupling sleeve 30a is moved rightward from the illustrated neutral position and meshed with the clutch gear 30c, the fourth speed output gear 28 is drivingly coupled to the counter shaft 10 so that the fourth speed can be selected as will be described later. And

  Next, the control configuration will be described. FIG. 2 is a control block diagram showing a control configuration of the twin clutch type automatic manual transmission.

  Various sensor signals are input to the transmission controller 50. Specifically, as various sensors, an engine speed sensor 41 for detecting the engine speed, a vehicle speed sensor 42 for detecting the vehicle speed, an inhibitor switch 43 for detecting a select lever position (range position signal) selected by the driver, an accelerator pedal An APO sensor 44 that detects the opening APO, a stroke sensor 45 that detects the stroke positions of the synchronous mesh mechanisms 21, 22, 29, and 30 and a hydraulic switch 46 that detects the engagement pressure of each of the clutches C1 and C2 are provided.

  Also, a hydraulic control valve unit C / that supplies an engagement pressure or an operating pressure to the clutches C1, C2 and the respective synchronous meshing mechanisms 21, 22, 29, 30 using an oil pump O / P driven by the engine 1 as a hydraulic pressure source. V is provided.

  An engine controller 60 that controls the driving state of the engine 1 is also provided. The engine controller 60 controls engine output torque and engine speed based on various sensor signals. When engine torque down control is performed, for example, a signal for reducing the throttle opening may be output to an actuator for controlling the throttle opening, or retard for delaying the ignition timing may be performed. Not limited.

  The transmission controller 50 selects a desired gear position based on various sensor signals and outputs a control signal to the control valve C / V. At the same time, a torque down request signal is output to the engine controller 60 as necessary at the time of shifting or starting.

  Next, the automatic shifting operation of the twin clutch type automatic manual transmission according to the above embodiment will be described.

  In non-traveling ranges such as neutral (N) range and parking (P) range where power transmission is not desired, both automatic wet-rotating clutches C1 and C2 are released, and synchronous meshing mechanisms 21, 22, and 29 are used. , 30 are set to the neutral position shown in the figure to bring the twin clutch automatic manual transmission into a neutral state where no power is transmitted. In this case, both the clutches C1 and C2 are release side clutches.

  In a driving range such as the D range in which forward power transmission is desired and the R range in which reverse power transmission is desired, hydraulic oil from an oil pump (not shown) driven by the engine 1 is used as a medium. In addition to shifting the coupling sleeves 21a, 22a, 29a, 30a of the synchronous mesh mechanisms 21, 22, 29, 30 to each other, the clutch C1, C2 is engaged / released to control each forward shift stage and reverse shift stage. You can choose.

  When the first speed is desired in the forward travel range such as the D range, the coupling sleeve 21a of the synchronous meshing mechanism 21 is moved left to drive-couple the gear 14 to the countershaft 10, and thereby the first odd-numbered shift stage 1 After the pre-shift to speed, the automatic wet rotation clutch C1 that was released in the non-traveling range is engaged.

  As a result, the engine rotation from the clutch C1 is output from the output shaft 6 via the first input shaft 4, the first speed gear set G1, the countershaft 10, and the output gear sets 11 and 12, and transmits power at the first speed. It can be carried out. In this case, the clutch C1 is a fastening side clutch, and the clutch C2 is a releasing side clutch.

Note that when the selection of the first speed is for starting, smooth front start without starting shock is performed by slip engagement control for engaging and proceeding with the clutch C1. Specifically, the speed ratio is calculated from the input / output rotational speed of the clutch C1, and the torque capacity coefficient τ is set based on the speed ratio. A large torque capacity coefficient is set when the speed ratio is small, and a small torque capacity coefficient is set when the speed ratio is large (<1). Then, the engagement torque TC1 of the clutch C1 is determined based on the following equation. Note that Ne is the engine speed.
TC1 ＝ τ × Ne ²

  When the first speed is selected in response to the selection operation from the N range to the D range, the coupling sleeve 30a of the synchronous meshing mechanism 30 is moved to the left simultaneously with the pre-shifting of the odd speed stage to the first speed. The gear 26 is driven and connected to the countershaft 10 to complete the pre-shift to the second speed of the even gear group.

  Therefore, since the clutch C2 continues to be released in the non-traveling range, the second speed is not selected.

  When upshifting from 1st speed to 2nd speed, even when N → D is selected, the even gear group is preshifted to 2nd speed as described above, so clutch C1 is released and released in the non-traveling range. When the clutch C2 is engaged (slip engagement control), the upshift from the first speed to the second speed can be performed by changing both clutches. In this case, the clutch C1 is a disengagement side clutch, and the clutch C2 is an engagement side clutch.

  As a result, the engine rotation from the clutch C2 is output from the output shaft 6 via the second input shaft 5, the second speed gear set G2, the counter shaft 10, and the output gear sets 11, 12, and transmits power at the second speed. It can be carried out.

  When upshifting from the second speed to the third speed, the coupling sleeve 21a of the synchronous meshing mechanism 21 is returned to the neutral position to disconnect the gear 14 from the countershaft 10, and the coupling sleeve 22a of the synchronous meshing mechanism 22 is moved to the right. The gear 19 is driven and connected to the first input shaft 4, and after this, the odd-numbered speed group 1 → 3 preshift, the clutch C2 is released and the clutch C1 is engaged (slip engagement control). The upshift from the second speed to the third speed is performed by changing both clutches. In this case, the clutch C1 is a fastening side clutch, and the clutch C2 is a releasing side clutch.

  As a result, the engine rotation from the clutch C1 is output from the output shaft 6 via the first input shaft 4, the third speed gear set G3, the counter shaft 10, and the output gear sets 11, 12, and transmits power at the third speed. It can be carried out.

  When upshifting from the third speed to the fourth speed, the coupling sleeve 30a of the synchronous meshing mechanism 30 is returned to the neutral position to disconnect the gear 26 from the countershaft 10, and the coupling sleeve 30a of the synchronous meshing mechanism 30 is moved to the right. The gear 28 is driven and coupled to the countershaft 10, and after this, even after the even gear group 2 → 4 preshift, the clutch C1 is released and the clutch C2 is engaged (slip engagement control), that is, both clutches. The upshift from the 3rd speed to the 4th speed is performed by switching. In this case, the clutch C1 is a disengagement side clutch, and the clutch C2 is an engagement side clutch.

  As a result, the engine rotation from the clutch C2 is output from the output shaft 6 via the second input shaft 5, the fourth speed gear set G4, the counter shaft 10, and the output gear sets 11, 12, and transmits power at the fourth speed. It can be carried out.

  When upshifting from the fourth speed to the fifth speed, the coupling sleeve 22a of the synchronous meshing mechanism 22 is returned to the neutral position to disconnect the gear 19 from the first input shaft 4, and the coupling sleeve 22a of the synchronous meshing mechanism 22 is used. The gear 31 is connected directly to the first input shaft 4 and the odd-numbered gear group 3 → 5 pre-shift is thereby released, and then the clutch C2 is released and the clutch C1 is engaged (slip engagement control). That is, the upshift from the fourth speed to the fifth speed is performed by changing both clutches. In this case, the clutch C1 is a fastening side clutch, and the clutch C2 is a releasing side clutch.

  As a result, engine rotation from the clutch C1 is output from the output shaft 6 via the first input shaft 4, the fifth speed gear set G5, the countershaft 10, and the output gear sets 11, 12, and transmits power at the fifth speed. It can be carried out.

  When upshifting from the fifth speed to the sixth speed, the coupling sleeve 30a of the synchronous meshing mechanism 30 is returned to the neutral position to disconnect the gear 28 from the countershaft 10, and the coupling sleeve 29a of the synchronous meshing mechanism 29 is moved to the left. The gear 24 is driven and connected to the countershaft 10, and after this, even after the even gear group 4 → 6 preshift, the clutch C1 is released and the clutch C2 is engaged (slip engagement control). The upshift from the 5th speed to the 6th speed is performed by changing over. In this case, the clutch C1 is a disengagement side clutch, and the clutch C2 is an engagement side clutch.

  As a result, engine rotation from the clutch C2 is output in the axial direction from the output shaft 6 via the second input shaft 5, the sixth speed gear set G6, the countershaft 10, and the output gear sets 11, 12, and at the sixth speed. Power transmission can be performed.

  In addition, when downshifting from the sixth speed to the first speed in sequence, by performing the shift control opposite to the upshift, the preshift in the reverse direction and the engagement / release control of the clutches C1 and C2 are performed as described above. Thus, a predetermined downshift can be performed.

  When reverse travel is desired and the non-travel range is switched to the R range, the coupling sleeve 21a of the synchronous meshing mechanism 21 is moved to the right from the neutral position, and the gear 16 is drivably coupled to the countershaft 10, thereby generating an odd number. After the preshift of the gear group to the reverse gear, the automatic wet rotation clutch C1 that has been released in the non-traveling range is engaged. In this case, the clutch C1 is a fastening side clutch, and the clutch C2 is a releasing side clutch.

  As a result, the engine rotation from the clutch C1 is output from the output shaft 6 via the first input shaft 4, the reverse gear set GR, the countershaft 10, and the output gear sets 11 and 12, and at this time, the reverse gear set GR rotates the rotation direction. Therefore, power transmission at the reverse gear can be performed.

  At the time of starting at the reverse gear, smooth start without start shock is performed by slip engagement control for engaging and proceeding with the clutch C1.

[N → D select control process when accelerator is ON]
Next, a control process when N → D selection control is performed in a state in which the driver depresses the accelerator pedal while the N range is selected will be described. FIG. 3 is a flowchart showing the select control process. This flowchart is a flowchart executed when an N → D selection is made with the accelerator pedal depressed. Therefore, in the initial state in which this process is started, the torque limit value of the engine torque is set to MAX engine torque (maximum value of engine torque). Further, the engagement torque control of the clutch C1 is executed in parallel.

  In step S1, it is determined whether or not the synchronous mesh mechanism 21 can transmit torque. If it is determined that torque can be transmitted, the process proceeds to step S3. If it is determined that torque cannot be transmitted, the process proceeds to step S2.

  Here, whether or not the synchronous mesh mechanism 21 can transmit torque means whether or not the gear 14 has reached the state where it is drivingly coupled to the countershaft 10 by the movement of the coupling sleeve 21a. The synchronous engagement mechanism 21 is only connected to the countershaft 10 when the rotational speeds of both are synchronized and the bokeling spline teeth mesh with the clutch gear spline teeth. In the first embodiment, since the stroke sensor 45 that detects the movement of the coupling sleeve 21a is provided, it may be determined that torque can be transmitted when the value of the stroke sensor 45 moves by a predetermined value or more.

  In step S2, it is determined whether or not the backlash of the clutch C1 has been completed. If it is determined that the clutch C1 has not been completed, the process proceeds to step S3. If it is determined that the clutch C1 has been completed, the process proceeds to step S7. Here, the backlash completion means that the piston of the clutch C1 has moved to the torque transmission start position.

  In the case where the timer is managed, this process performs a quick hydraulic filling process (so-called precharge process) for a predetermined time, and it may be determined whether or not the predetermined time has elapsed. Further, since the hydraulic switch 46 is provided in the first embodiment, it may be determined that the precharge is completed when the hydraulic switch 46 is turned on.

  In step S3, a torque limiter basic value that is an upper limit of the engine torque is set. This basic value of the torque limiter is a value that can suppress idling of the engine 1 and can settle to about the idling speed.

  In step S4, it is determined whether or not the current engine torque is greater than the torque limiter basic value by a predetermined value or more. If it is greater than the predetermined value, the process proceeds to step S5. Otherwise, the process proceeds to step S6.

  In step S5, the torque limiter value is set to a value obtained by subtracting a predetermined value from the current engine torque. This is to give a sense of incongruity when the engine torque is reduced to the torque limiter basic value at once, and the torque is gradually reduced.

  In step S6, the torque limiter value is set as a torque limiter basic value.

  In step S7, it is determined whether or not a release request for the clutch C1 is established. If established, the process proceeds to step S3. If not established, the process proceeds to step S8. Here, the release request is made for the purpose of avoiding engine stall due to a decrease in vehicle speed, sudden deceleration, or the like.

  In step S8, the torque limiter basic value is invalidated. Specifically, the torque limiter value is set to the MAX engine torque (initial state).

  In step S9, it is determined whether or not the current engine torque is equal to or less than a value obtained by adding a predetermined value to the torque limiter value (torque limiter basic value for the first time) in the previous control cycle. Proceed to S10, otherwise proceed to step S11.

  In step S10, the torque limiter value is set to a value obtained by adding a predetermined value from the current engine torque.

  In step S11, the torque limiter value is set to a value obtained by adding a predetermined value to the previous torque limiter value.

  Next, the operation based on the flowchart will be described. Here, in describing the operation of the first embodiment, a case where torque reduction is not performed during N → D selection will be described as a comparative example. FIG. 4 is a time chart of a comparative example.

  At time t1, the driver depresses the accelerator pedal with the N range selected. Then, the engine speed increases as the engine torque increases. At this time, the first input shaft 4 and the like are also rotated by the drag torque of the clutch C1, and the rotational speed increases. Therefore, at the initial stage of the engine speed increase, the engine torque temporarily becomes high due to the inertia torque of the first input shaft 4 and the like.

  When the inertia torque decreases and the load acting on the engine 1 becomes stable at time t2, the engine torque and the engine speed corresponding to the throttle opening are stabilized. Since the accelerator pedal is depressed, the engine is stable at a speed higher than the idle speed.

  When N → D selection is performed at time t 3, a preshift request is first output to the synchronization gear mechanism 21. Since the countershaft 10 is now stopped, when the coupling sleeve 21a of the synchronous meshing mechanism 21 is moved, the rotational speed of the first input shaft 4 is gradually pushed down.

  At time t4, when the rotation of the first input shaft 4 is stopped and synchronized with the countershaft 10, the engagement of the synchronization gear mechanism 21 is completed. So-called synchro control is performed from time t3 to time t4.

  When the engagement of the synchronous engagement mechanism 21 is completed at time t4, a precharge process for the clutch C1 is then performed. Specifically, a predetermined hydraulic pressure is supplied to the cylinder chamber of the clutch C1 for a predetermined time and the piston is stroked to perform backlashing. Although it is desirable that the backlash is completed quickly, if the predetermined hydraulic pressure is continuously applied, the piston stroke speed becomes excessive and affects the sound vibration performance, etc., so the predetermined hydraulic pressure is set lower in the latter half.

  When the precharge process is completed at time t5, the engagement process of the clutch C1 is started. This engagement process is set according to the speed ratio of the clutch C1, the engagement capacity, and the engine speed. Therefore, since the engine speed is high and the speed ratio of the first input shaft 4 is large, a high fastening pressure is supplied, and the rotation speed of the first input shaft 4 increases at a stretch. Thereafter, when the engine speed decreases and the speed ratio decreases, the engagement pressure to the clutch C1 gradually decreases.

  When the differential rotational speed of the clutch C1 is lost at time t6, the clutch C1 is brought into a completely engaged state.

  Here, as described at time t5, when the engine speed is high at the time of starting, the engagement torque of the clutch C1 also increases, and an engagement shock is likely to occur due to the inertia torque when the engine speed is reduced. This may give the driver a feeling of protrusion. Further, since the engagement is completed from the state where the differential rotation speed is large, the slip amount generated in the clutch C1 is large, and there is a concern about heat generation.

  Thus, in the first embodiment, the engine torque is reduced in the N → D selection control in a state where the accelerator pedal is depressed in the N range.

  FIG. 5 is a time chart of the first embodiment. Since the time from t1 to t3 is the same as that in the comparative example, the description is omitted.

  When N → D selection is made at time t3, engine torque reduction is executed. Specifically, in step S3, a torque limiter basic value is set, and control is performed so that the engine speed is close to the idle speed. At the same time, a pre-shift request is output to the synchronization gear mechanism 21. Since the countershaft 10 is now stopped, when the coupling sleeve 21a of the synchronous meshing mechanism 21 is moved, the rotational speed of the first input shaft 4 is gradually pushed down. At this time, in the comparative example, it was necessary to reduce the rotation speed of the first input shaft 4 against the drag torque. On the other hand, in Example 1, since the engine torque is limited, the engine speed itself decreases, so there is no need to resist the drag torque, and the durability of the synchronous engagement mechanism 21 is deteriorated. There is no.

  When the engagement of the synchronous engagement mechanism 21 is completed at time t4, a precharge process for the clutch C1 is then performed. At this time, the setting of the torque limiter basic value is still continued, so that the engine speed does not increase.

  When the precharge process is completed at time t5, the torque limiter basic value is set to the MAX engine torque, and the torque limiter value is gradually increased. The ascending gradient at this time is raised within a range that does not give the driver a feeling of protrusion.

  At the same time, the engagement process of the clutch C1 is started. Since this engagement process is set according to the speed ratio of the clutch C1, the engagement capacity, and the engine speed, since the engine speed is low and the speed ratio of the first input shaft 4 is large, a low engagement pressure is supplied. The

  Since the torque limiter value is gradually increased, the engine torque gradually increases, and accordingly, the engine speed gradually increases, and at the same time, the rotation speed of the first input shaft 4 also gradually increases.

  When the differential rotational speed of the clutch C1 is lost at time t6, the clutch C1 is brought into a completely engaged state.

  In other words, during N → D selection with the accelerator pedal depressed, the engine torque is limited to a predetermined value that can be maintained at about the idle speed, thereby suppressing the engagement shock and suppressing the heat generation of the clutch C1. Can do.

  As described above, in the transmission control apparatus according to the first embodiment, the following effects can be obtained.

  (1) In a transmission control device that changes the torque output from the engine 1 to a desired value by a power transmission mechanism (clutch C1, C2, synchronous mesh mechanism 21, 22, 29, 30) and outputs the power It is determined whether or not the transmission mechanism can transmit torque (steps S1 and S2). When it is determined that torque transmission is impossible, an upper limit setting means (step S3) is provided for setting an upper limit (torque limiter basic value) for the engine torque. It was.

  In other words, the output torque of the engine 1 is controlled according to the torque transmission state of the power transmission mechanism (clutch C1, C2, synchronous engagement mechanism 21, 22, 29, 30), and the power transmission mechanism (clutch C1, C2, synchronous) The heat generated in the meshing mechanisms 21, 22, 29, 30) was reduced.

  That is, by reducing the heat generation of the power transmission mechanism while suppressing the engine speed from rising, it is possible to improve the durability of the power transmission mechanism and to suppress a shock that occurs at the start of torque transmission.

  (2) The torque limiter basic value is a value at which the engine speed is less than or equal to a predetermined value. That is, by managing the increase in the engine speed, it is possible to reduce the amount of heat generated while mitigating the shock that occurs when the clutch is engaged thereafter. Note that by setting the idle speed as the predetermined value, it is possible to minimize the engine speed and the slip amount of the power transmission mechanism.

  (3) The upper limit setting means (step S3) maintains the upper limit setting until the looseness of the clutch C1 is completed.

  That is, by suppressing the engine speed from rising, it is possible to mitigate the engagement shock that occurs when the clutch C1 is engaged after the establishment of the power transmission path. Also, if the clutch speed is driven by the engine speed due to the dragging of the clutch C1, etc., the differential speed to be absorbed when establishing the power transmission path is suppressed by suppressing the engine speed from rising. The number is reduced, and durability can be improved.

  (4) The backlash is reduced by moving the clutch C1 to the torque transmission start position.

  That is, by releasing the torque limiter when the controllability of the clutch C1 is ensured, the engine speed can be prevented from rising.

  (5) After canceling the setting of the torque limiter basic value, the engine torque is increased by a predetermined gradient (steps S9, S10, S11).

  That is, by managing the rising gradient at the time of engine torque recovery, it is possible to avoid sudden feeling due to engine torque recovery, and engine speed increase or retraction due to a time lag with clutch control.

  (6) The upper limit setting means (step S3) maintains the setting of the torque limiter basic value until the meshing of the synchronous meshing mechanism 21 is completed.

  That is, when the first input shaft 4 is rotated by the engine speed due to the dragging of the clutch C1, etc., it should be absorbed when the power transmission path is established by suppressing the engine speed from rising. The differential rotation speed is reduced, the inhibition of synchro control is reduced, and at the same time, the durability can be improved.

  (7) The engagement torque of the clutch C1 is a high engagement torque when the engine speed is high, and is a low engagement torque when the engine speed is low. That is, a vehicle that does not include a torque converter needs to improve drivability by slip control of the clutch C1 in an extremely low vehicle speed region or the like. At this time, by controlling the fastening torque in accordance with the engine speed, for example, if the engine speed is to be increased, the fastening torque is increased to suppress the increase in the rotational speed and prevent the engine from rising. On the other hand, when the engine speed is lowered, the fastening torque is reduced to avoid excessive engine speed reduction and prevent engine stall.

  In the above configuration, at the time of N → D selection with the accelerator pedal depressed, the engine speed is kept low, so that the clutch C1 does not have excessive engagement torque. Therefore, it is possible to suppress the heat generation of the clutch C1 while preventing the engine speed from rising and start smoothly.

It is a skeleton diagram showing a twin clutch type automatic manual transmission to which the clutch cooling device of the present invention can be applied. 3 is a block diagram illustrating a control configuration of Embodiment 1. FIG. 3 is a flowchart illustrating select control processing according to the first exemplary embodiment. It is a time chart at the time of N-> D selection in a comparative example. 3 is a time chart at the time of N → D selection in the first embodiment.

Explanation of symbols

1 Engine 2 Crankshaft
C1 Odd-speed clutch
C2 Even-speed clutch 3 Clutch drum 4 First input shaft 5 Second input shaft 6 Output shaft 7 Clutch hub 8 Clutch hub
10 Counter shaft
11 Counter gear
12 Output gear
G1 1st gear set
G2 2nd gear set
G3 3rd speed gear set
G4 4th gear set
G5 5th gear set
G6 6th gear set
GR reverse gear set
21 1st gear-reverse synchronous meshing mechanism
22 3-speed-5-speed synchronous meshing mechanism
29 6-speed synchronous meshing mechanism
30 2nd and 4th gear synchronous meshing mechanism

Claims (4)

In a transmission control device that outputs a torque output from an engine by changing the torque to a desired value via a power transmission mechanism,
When the driver maintains the depression of the accelerator pedal and switches the range position of the transmission from the neutral range to the travel range, it is determined whether or not the power transmission mechanism can transmit torque, and it is determined that torque cannot be transmitted. When the engine rotation speed is lower than the rotation speed according to the depression of the accelerator pedal, an upper limit setting means for setting an upper limit on the engine torque is provided,
The power transmission mechanism is a friction clutch;
Upper limit setting means, transmission control device, characterized by maintaining the upper limit set to play reduction of the friction clutch is completed. The transmission control device according to claim 1,
The backlashing means that the friction clutch is moved to a torque transmission start position . The transmission control device according to claim 1 or 2,
The transmission control apparatus , wherein after the upper limit setting is canceled, the torque of the engine is increased by a predetermined upward gradient . The transmission control device according to any one of claims 1 to 3,
The transmission control device according to claim 1, wherein the engagement torque of the friction clutch is a high engagement torque when the engine speed is high, and is a low engagement torque when the engine speed is low .

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