JP2008180260A - Automatic transmission control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic transmission control device for preventing the sudden deceleration of a vehicle due to engine brake even in a stepped variable transmission. <P>SOLUTION: A control means detects the deceleration of the vehicle during transmitting torque to a driving wheel via a current shift stage when an accelerator is released. When the deceleration of the vehicle is greater than a predetermined deceleration overunning threshold value, it reduces a torque transmitting amount in the current shift stage and executes deceleration reducing control to increase the torque transmitting amount in a shift stage higher than the current shift stage. When the deceleration of the vehicle is smaller than a predetermined deceleration underrunning threshold value, or when the vehicle is accelerated during releasing the accelerator, it reduces the torque transmitting amount in the current shift stage and executes deceleration increasing control to increase the torque transmitting amount in a shift stage lower than the current shift stage. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an engine brake control when an accelerator pedal is released in an automatic transmission, particularly a twin clutch type automatic transmission.

Conventionally, in a continuously variable transmission of a vehicle, torque transmission from an engine is detected by detecting vehicle deceleration when the accelerator pedal is released and continuously changing a gear ratio according to the vehicle deceleration ( Some engine brakes are continuously changed to prevent sudden deceleration of the vehicle (see, for example, Patent Document 1).
JP-A-9-100903

  However, the above-mentioned prior art continuously transmits torque input from the engine on the premise of continuous gear ratio control of the continuously variable transmission, but in a stepped transmission that can perform only stepwise gear ratio control. In this case, torque input from the engine can be transmitted only in stages.

  Therefore, when the vehicle deceleration due to the transmission torque from the engine (deceleration due to engine braking) is larger than the current vehicle deceleration when the accelerator is released, the vehicle may be decelerated suddenly by engine braking. Conversely, if the deceleration due to engine braking is small, a desired engine brake may not be obtained.

  Therefore, in the stepped transmission, there is a problem that the vehicle sudden deceleration due to the engine brake cannot be prevented even if the concept of the above prior art based on the continuously variable transmission is used.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a control device for an automatic transmission that can prevent a sudden deceleration of a vehicle due to an engine brake even in a stepped transmission. is there.

  In order to achieve the above object, according to the present invention, an input shaft, an output shaft provided in parallel to the input shaft, a transmission gear provided for each of a plurality of shift stages, and engagement / release of the transmission gear. In the control device for the automatic transmission having the control means for performing the control, the control means detects the vehicle deceleration when the accelerator is released while torque is being transmitted to the driving wheel via the current gear stage. When the vehicle deceleration is larger than a predetermined deceleration excessive threshold, the torque transmission amount at the current gear stage is decreased and the torque transmission amount at a gear stage higher than the current gear stage is increased. When speed reduction control is executed and the vehicle deceleration is smaller than a predetermined deceleration under threshold or when the vehicle accelerates while releasing the accelerator, the torque transmission amount at the current shift stage is reduced, Serial was decided to perform the deceleration increase control for increasing the torque transmission amount of the lower shift speed than the current gear.

  Therefore, it is possible to provide a control device for an automatic transmission that can prevent sudden vehicle deceleration due to engine braking even in a stepped transmission.

  The best mode for carrying out the automatic transmission control apparatus of the present invention will be described below based on the embodiments shown in the drawings.

[overall structure]
Example 1 will be described with reference to FIGS. FIG. 1 is an overall system diagram showing a twin clutch type automatic manual transmission (transmission) to which an automatic transmission control device according to a first embodiment is applied. The twin-clutch automatic manual transmission includes a transmission case 1, a transmission input shaft 2, first and second clutches CA and CB, a torsional damper 3, an oil pump 4, first and second input shafts 5 and 6, An output shaft 15 is provided.

  The rotational speeds Ni1 and Ni2 of the first and second input shafts 5 and 6 are detected by the first and second input shaft rotational speed sensors N1 / Sen and N2 / Sen, respectively, and the rotational speed No of the output shaft 15 is the output shaft rotational speed. It is detected by the number sensor No / Sen. The detected Ni1, Ni2, No are output to the automatic MT controller 47.

  The first clutch CA is for odd gears (first speed, third speed, fifth speed, reverse speed), and the second clutch CB is for even gear speeds (second speed, fourth speed, sixth speed). The drive sides of both clutches CA and CB are connected via a torsional damper 3 to a transmission input shaft 2 for inputting a driving force from a driving source such as an engine.

  The driven side of the first clutch CA inputs the driving force from the driving source to the first input shaft 5 at the time of engagement by selecting an odd gear. The driven side of the second clutch CB inputs the driving force from the driving source to the second input shaft 6 at the time of engagement by selection of the even-numbered gear.

  The oil pump 4 is always operated by a drive source, and executes engagement / release control of the first and second clutches CA and CB and shift speed selection control by a shift actuator using the oil discharged from the oil pump 4 as a hydraulic source. To do.

  The second input shaft 6 is a hollow shaft, and the first input shaft 5 is a solid shaft. The second input shaft 6 is rotatably supported in a concentric state via the front side needle bearing 7 and the rear side needle bearing 8 with respect to the first input shaft 5.

  The second input shaft 6 has a hollow cylindrical shape and is rotatably supported by a ball bearing 9 with respect to the front wall 1 a of the transmission case 1. The first input shaft 5 is provided on the inner peripheral side of the second input shaft 6 and protrudes, and the rear end portion 5a of the protruded first input shaft 5 passes through the intermediate wall 1b of the transmission case 1 in the intermediate wall 1b. The ball bearing 10 is rotatably supported.

  The first input shaft 5 is connected to the transmission output shaft 11 at the rear end portion 5a. The transmission output shaft 11 is coaxial with the first input shaft 5, and is rotatably supported on the rear end wall 1 c of the transmission case 1 via a tapered roller bearing 12 and an axial bearing 13. The first input shaft 5 is rotatably supported at the rear end portion 5a via a needle bearing 14.

  The output shaft 15 is arranged in parallel to the first input shaft 5, the second input shaft 6, and the transmission output shaft 11, and the front end wall 1a of the transmission case 1 through the roller bearings 16, 17, 18 and the intermediate It is rotatably supported on the wall 1b and the rear end wall 1c.

  An output gear 19 is integrally provided at the rear end of the output shaft 15, and an output gear 20 is provided on the transmission output shaft 11. The output gear 19 and the output gear 20 are engaged with each other to engage the output shaft 15 with the transmission output shaft 11.

  On the first input shaft 5, an odd-numbered gear group (first speed, third speed, reverse), that is, a first speed gear G1, a reverse gear GR, and a third speed gear G3 are arranged in order from the left side in the drawing.

  The first speed gear G1 is configured by meshing a first speed input gear 21 provided at the rear end portion 5a of the first input shaft 5 and a first speed output gear 22 provided on the output shaft 15.

  The reverse gear GR includes a reverse input gear 23 provided at the rear end portion 5a of the first input shaft 5, a reverse output gear 24 provided on the output shaft 15, a reverse idler gear 25 meshing with both gears 23, 24, It consists of. The reverse idler gear 25 is rotatably supported with respect to a reverse idler shaft 25a that protrudes from the intermediate wall 1b of the transmission case 1.

  The third speed gear G3 is configured by meshing a third speed input gear 26 provided at the rear end portion 5a of the first input shaft 5 and a third speed output gear 27 provided on the output shaft 15.

  A 1-R synchronous meshing mechanism 100 is provided on the output shaft 15 between the first speed gear G1 and the reverse gear GR. Then, the first-speed output gear 22 is engaged with the output shaft 15 by causing the coupling sleeve 101 of the 1-R synchronous meshing mechanism 100 to stroke leftward from the neutral position shown in the figure and to be splined to the clutch gear 103 ′. The first speed can be selected.

  Further, the coupling sleeve 101 of the 1-R synchronous meshing mechanism 100 is stroked to the right from the neutral position shown in the figure, and the clutch gear 103 is splined to engage the reverse output gear 24 with the output shaft 15. The reverse speed can be selected.

  On the rear end portion 5a of the first input shaft 5 between the third speed gear G3 and the output gear 20, a 3-5 synchronous meshing mechanism 200 is provided. Then, the third-speed input gear 26 is moved to the first input shaft 5 by causing the coupling sleeve 201 of the 3-5 synchronous meshing mechanism 200 to stroke leftward from the neutral position shown in the figure and by spline fitting with the clutch gear 203 ′. The third gear can be selected.

  Further, the first input shaft 5 and the output gear 20 are directly connected by causing the coupling sleeve 201 of the 3-5 synchronous meshing mechanism 200 to stroke rightward from the neutral position shown in the figure and to be splined to the clutch gear 203. 5 speed can be selected.

  Between the second input shaft 6 and the output shaft 15, gears of even-numbered speed groups (second speed, fourth speed, sixth speed), that is, in order from the front side, the sixth speed gear G6, the second speed gear G2, and A fourth speed gear G4 is arranged.

  The sixth speed gear G6 is configured by meshing a sixth speed input gear 30 provided on the second input shaft 6 and a sixth speed output gear 31 provided on the output shaft 15.

  The second speed gear G2 is configured by meshing a second speed input gear 32 provided on the second input shaft 6 and a second speed output gear 33 provided on the output shaft 15.

  The 4-speed gear G4 is configured by meshing a 4-speed input gear 34 provided on the second input shaft 6 and a 4-speed output gear 35 provided on the output shaft 15.

  A 6-N synchronous meshing mechanism 300 is provided on the output shaft 15 at the side of the sixth speed gear G6. Then, the 6-speed output gear 31 is engaged with the output shaft 15 by causing the coupling sleeve 301 of the 6-N synchronous meshing mechanism 300 to stroke leftward from the neutral position shown in the figure and by spline fitting with the clutch gear 303. 6th speed can be selected.

  A 2-4 synchronous meshing mechanism 400 is provided on the output shaft 15 between the second gear G2 and the fourth gear G4. Then, the second-speed output gear 33 is engaged with the output shaft 15 by causing the coupling sleeve 401 of the 2-4 synchronous meshing mechanism 400 to stroke leftward from the neutral position shown in the figure and to be splined to the clutch gear 403 ′. The second speed can be selected.

  Further, the 4th-speed output gear 35 is engaged with the output shaft 15 by causing the coupling sleeve 401 of the 2-4 synchronous meshing mechanism 400 to stroke rightward from the neutral position shown in the figure and to be splined to the clutch gear 403. 4 speed can be selected.

  Further, 3-5, 1-R, 6-N, 2-4 shift forks 41 to 44, an actuator unit 45, a clutch hydraulic module 46, and an automatic MT controller 47 (control means) are provided as a shift control system. Yes.

  The 3-5 shift fork 41 is engaged with the coupling sleeve 201 of the 3-5 synchronous meshing mechanism 200 and is fixed to the first shift rod 48. The first shift rod 48 is supported so as to be movable in the axial direction with respect to the front end wall 1 a and the intermediate wall 1 b of the transmission case 1.

  Then, the 3-5 shift bracket 49 is fixed to the first shift rod 48, and the end portion of the 3-5 shift bracket 49 is loosely supported by the spool connecting shaft portion of the 3-5 shift actuator 50. That is, the 3-5 shift fork 41 strokes from the neutral position shown in the drawing to the left (when the third speed is selected) or right (when the fifth speed is selected) according to the spool operation of the 3-5 shift actuator 50.

  The 1-R shift fork 42 engages with the coupling sleeve 101 of the 1-R synchronous meshing mechanism 100 and is provided on the second shift rod 51 so as to be capable of stroke in the axial direction. The second shift rod 51 is provided in a fixed state in the axial direction with respect to the front end wall 1 a and the intermediate wall 1 b of the transmission case 1.

  The end portion of the bracket arm portion 42b that is integrally formed with the bracket cylindrical portion 42a of the 1-R shift fork 42 is idled and supported by the spool connecting shaft portion of the 1-R shift actuator 52. That is, the 1-R shift fork 42 strokes from the neutral position shown in the drawing to the left (when the first speed is selected) or right (when the reverse speed is selected) according to the spool operation of the 1-R shift actuator 52.

  The 6-N shift fork 43 is engaged with the coupling sleeve 301 of the 6-N synchronous meshing mechanism 300 and is provided on the second shift rod 51 that is fixed in the axial direction with respect to the transmission case 1 so as to be able to stroke in the axial direction. Then, the end portion of the bracket arm portion 43 b formed integrally with the bracket cylindrical portion 43 a of the 6-N shift fork 43 is idled and supported by the spool connecting shaft portion of the 6-N shift actuator 53.

  That is, the 6-N shift fork 43 strokes from the neutral position shown in the drawing to the left (when 6th speed is selected) according to the spool operation of the 6-N shift actuator 53.

  The 2-4 shift fork 44 is engaged with the coupling sleeve 401 of the 2-4 synchronous meshing mechanism 400, and is provided on the second shift rod 51 fixed in the axial direction with respect to the transmission case 1 so as to be capable of stroke in the axial direction.

  The end portion of the bracket arm portion 44b formed integrally with the bracket cylindrical portion 44a of the 2-4 shift fork 44 is loosely supported by the spool connecting shaft portion of the 2-4 shift actuator 54. That is, the 2-4 shift fork 44 strokes from the neutral position shown in the figure to the left (when the second speed is selected) or right (when the fourth speed is selected) according to the spool operation of the 2-4 shift actuator 54.

  The actuator unit 45 is provided with shift actuators 50, 52, 53, 54 of 1-R, 3-5, 6-N, and 2-4 shift forks 41 to 44, and an actuator hydraulic module 59. The actuator unit 45 is fixed to the lower part, upper part, side part or the like of the transmission case 1 and is shifted by a shift position sensor 55, 56, 57, 58 (position detecting means) of each actuator 50, 52, 53, 54. Is detected.

  The actuator hydraulic module 59 generates an even speed step pressure Pe and an odd speed step pressure Po using the line pressure PL adjusted by the clutch hydraulic module 46 as a source pressure. Further, the actuator operating pressure is supplied to the shift pressure oil path to each of the shift actuators 50, 52, 53, 54 in accordance with the selected gear position.

  The clutch hydraulic module 46 regulates the line pressure PL based on the oil discharged from the oil pump 4, and creates a clutch control pressure for the first clutch CA based on the even speed step pressure Pe from the actuator hydraulic module 59. A clutch control pressure for the second clutch CB is generated based on the odd speed step pressure Po.

  The automatic MT controller 47 inputs information from a vehicle speed sensor, an accelerator opening sensor, a range position sensor, and other sensors / switches, and outputs a shift stage selection control command to each solenoid of the actuator hydraulic module 59. A clutch engagement control command (including a line pressure control command) is output to each solenoid of the clutch hydraulic module 46.

  In the first embodiment, the first input shaft 5 is connected to the first clutch CA and the second input shaft 6 is connected to the second clutch CB. Conversely, the second input shaft 6 is connected to the first clutch CA. And the first input shaft 5 may be connected to the second clutch CB. As for the shift speeds, the odd speed shift stages G1, G3, and G5 may be provided on the second input shaft 6 and the odd speed shift stages G2, G4, and G6 may be provided on the first input shaft 5 contrary to the first embodiment. .

[Hydraulic circuit]
FIG. 2 is a hydraulic circuit diagram illustrating the sequence solenoid OFF in the actuator hydraulic module 59 and the clutch hydraulic module 46 to which the start control device of the first embodiment is applied, and FIG. 3 is the actuator hydraulic pressure to which the start control device of the first embodiment is applied. FIG. 6 is a hydraulic circuit diagram showing a sequence solenoid On in the module 59 and the clutch hydraulic module 46.

  The actuator hydraulic module 59 includes eight oil passages 61, 62, 63, 64, 65, 66, 67, 68 for the four shift actuators 50, 52, 53, 54, four actuator solenoids 71, 72, The actuator hydraulic circuit is opened and closed by 73 and 74 and one sequence solenoid 75.

  The eight oil paths are the third speed pressure oil path 61, the fifth speed pressure oil path 62, the first speed pressure oil path 63, the reverse pressure oil path 64, the second speed pressure oil path 65, and the fourth speed pressure oil. A path 66, a sixth speed pressure oil path 67, and a neutral pressure oil path 68 are configured.

  The four actuator solenoids include a first actuator solenoid 71 and a second actuator solenoid 72 that generate the oil pressure of the even speed group, a third actuator solenoid 73 that generates the oil pressure of the odd speed group, and a fourth actuator solenoid 74. And composed of

  The sequence solenoid 75 is provided with a spool 76. If the spool 76 moves to the solenoid-off side, a low-speed gear (first speed, second speed, fourth speed, reverse speed) can be selected (see FIG. 2), and if it moves to the solenoid-on side, a high speed gear (third speed, fifth speed) , 6th gear) can be selected.

  The actuator hydraulic module 59 is provided with a clutch hydraulic module 46 and even and odd gear stage pressure solenoids 77 and 78. The line pressure PL is generated by the clutch hydraulic module 46, and the even and odd gear stage pressure solenoids 77 and 78 generate even and odd gear stage pressures Pe and Po based on the line pressure PL.

  The even speed step pressure Pe is output to the first and second actuator solenoids 71 and 72, and the odd speed step pressure Po is output to the third and fourth actuator solenoids 73 and 74. Note that the both speed stage pressure solenoids 77 and 78 are configured by VBS (variable bleed solenoid).

  The clutch hydraulic module 46 is provided with a line pressure solenoid 85 and first and second clutch control pressure solenoids 81 and 82. The first and second clutch pressures are detected by first and second clutch pressure sensors 83 and 85, respectively.

  The line pressure solenoid 85 adjusts the line pressure PL based on the oil discharged from the oil pump 4. Further, the first and second clutch control pressure solenoids 81 and 82 are respectively applied to the clutch control pressures PcA and PcB of the first and second clutches CA and CB based on the even and odd gear shift pressures Pe and Po from the actuator hydraulic module 59, respectively. Is generated.

  The line pressure solenoid 85 is constituted by a VBS (variable bleed solenoid), and the both clutch control pressure solenoids 81 and 82 are constituted by a VFS (variable force solenoid).

[Shift operation]
In the present automatic transmission, the first, third, and fifth speeds are distributed on the first input shaft 5, and the second, fourth, and sixth speeds are distributed on the second input shaft 6. 1. First and second clutches CA and CB are alternately engaged and released, and torque is transmitted to first and second input shafts 5 and 6 alternately.

  For example, when traveling at the first speed, the first clutch CA and the 1-R synchronous meshing mechanism 100 are engaged and engaged, and torque is transmitted by the first speed gear G1 on the first input shaft 5. During the 1-2 speed upshift, the 1-R synchronous meshing mechanism 100 is disengaged while disengaging the first clutch CA, the second clutch CB is engaged, and the 2-4 synchronous meshing mechanism 400 is on the second speed side. Engage.

  Accordingly, during the second speed traveling, the second speed gear G2 is engaged with the second input shaft 6, and the first speed gear G1 is engaged with the first input shaft 5 on the standby side (standby side input shaft preshift). . Since the first clutch CA is released, torque is not transmitted to the first input shaft 5, and torque is transmitted via the second clutch CB, the second input shaft 6, and the second speed gear G2.

  If the gear stage before the second speed traveling is the first speed, the first speed gear G1 is engaged with the first input shaft 5 on the standby side as described above (first speed preshift). On the other hand, if the gear stage before the second speed traveling is the third speed, the third speed gear G3 is engaged with the first input shaft 5 on the standby side (third speed preshift).

[Vehicle sudden deceleration prevention control by engine brake]
If the vehicle deceleration (engine brake) due to the torque transmitted from the engine is greater than the current vehicle deceleration when the accelerator is released, the vehicle may be decelerated suddenly. Conversely, if the engine brake is small, the desired engine brake cannot be obtained.

  In the case of a continuously variable transmission, when the accelerator is released, the gear ratio is continuously changed, so that torque transmission from the engine (engine brake) is continuously changed according to the vehicle deceleration to prevent sudden deceleration of the vehicle. Is possible. However, in the case of a stepped transmission, only a stepped gear ratio can be obtained. Therefore, if the gear ratio from when the accelerator is released is fixed, the deceleration by the engine brake and the vehicle deceleration current value deviate from each other. It suddenly slows down.

  Here, if the engine speed is the same, the transmission torque from the engine is reduced when the upshift is performed in the stepped transmission, and the engine transmission torque is increased when the downshift is performed. That is, the engine brake is increased by the downshift and is decreased by the upshift.

  Therefore, in this embodiment, when the engine brake is large with respect to the vehicle deceleration current value, deceleration reduction control by upshift (engine brake reduction control) is performed, and when the engine brake is small, deceleration increase control by downshift ( Perform engine brake increase control).

  For example, the accelerator is released during downhill descent at the second speed, and if the engine brake is excessive in the second speed gear G2, an upshift is performed to the third speed gear G3. If the engine brake is insufficient in the second gear G2, the downshift is performed to the first gear G1.

  As a result, when the accelerator is released, the difference between the deceleration due to the engine brake and the vehicle deceleration current value is reduced, and an appropriate engine brake is obtained even in the stepped transmission. If the vehicle accelerates while the accelerator is released, the engine brake increase control is performed by unconditionally downshifting.

  Note that the automatic MT controller 47 increases the first and second clutches as the difference between the vehicle deceleration −G and the excessive deceleration threshold −GH or the difference between the vehicle deceleration −G and the excessive deceleration threshold −GL increases. Increase the changing speed of the torque transmission amount of CA and CB. Thereby, an engine brake is generated appropriately and promptly.

  Further, the automatic MT controller 47 controls the sum of the torque transmission amount T · γA of the first clutch CA and the torque transmission amount T · γB of the second clutch CB to be equal to the torque T input to the transmission. . This prevents the driving force from being lost.

[Engine brake reduction control by 2-3 speed upshift]
(1st gear shift state)
When performing 2-3 speed upshift to reduce engine brake during traveling in the second speed (first gear G1 preshift state), the torque sharing ratio of the first clutch CA is increased and the torque sharing ratio of the second clutch CB is increased. The first speed gear G1 in the preshift state is released and the third speed gear G3 is engaged.

(3rd gear shift state)
When the 2-3 speed upshift is performed to reduce the engine brake during the 2nd speed traveling (the 3rd gear G3 pre-shift state), the 3rd gear G1 is already engaged with the first input shaft 5, so that the first It is only necessary to increase the torque sharing ratio of the clutch CA and lower the torque sharing ratio of the second clutch CB.

[Engine brake increase control by 2-1 speed downshift]
(1st gear shift state)
When the 2-1 speed downshift is performed to increase the engine brake during the second speed traveling (first speed gear G1 pre-shift state), the first clutch G1 is already engaged with the first input shaft 5 and therefore the second clutch CB. It is only necessary to increase the torque sharing rate of the first clutch CA by lowering the torque sharing rate.

(3rd gear shift state)
When the 2-1 speed downshift is performed to increase engine braking during the second speed traveling (third speed gear G3 pre-shift state), the torque sharing ratio of the first clutch CA is increased and the torque sharing ratio of the second clutch CB is decreased. At the same time, the third gear G3 in the pre-shift state is released and the first gear G1 is engaged.

  In any case, when the first and second clutches CA and CB are switched, the torque sharing ratios of the first and second clutches are changed by increasing / decreasing the fastening force of the clutches CA and CB. Further, the torque sharing ratio is determined so that the sum of the transmission torques TA and TB of the first and second clutches CA and CB becomes equal to the transmission input torque, thereby preventing driving force from being lost.

  Even if the torque transmission shaft is not switched between the first input shaft 5 and the second input shaft 6 as in the 2-3 speed upshift, the upshift on the same input shaft as in the 1-3 speed shift or A downshift may be performed to decrease / increase the engine brake.

[Engine brake control processing]
(Main flow)
FIG. 4 is a main flow of engine brake control processing.

  In step S1, it is determined whether or not the accelerator is turned off. If YES, the process proceeds to step S3, and if NO, the process proceeds to step S2.

  In step S2, normal processing is executed assuming that there is no engine brake generation request, and the control is terminated.

  In step S3, it is determined whether the current value of vehicle deceleration is less than the engine brake under-determination threshold GL. If YES, the process proceeds to step S100, and if NO, the process proceeds to step S4.

  In step S4, it is determined whether or not the current value of vehicle deceleration exceeds the engine brake excess determination threshold GL. If YES, the process proceeds to step S200, and if NO, the control is terminated.

  In step S100, the engine brake is insufficient, a deceleration increase process (engine brake increase) is executed, and the control is terminated.

  In step S200, the engine brake is excessive, the deceleration reduction process (engine brake reduction) is executed, and the control is terminated.

[Deceleration increase processing (engine brake increase processing)]
FIG. 5 is a flowchart showing the flow of deceleration increase processing (engine brake increase processing).

  In step S101, it is determined whether of the current gear stage and the gear stage engaged by the preshift, the gear stage having the lower gear ratio is engaged with the first or second input shaft 5 or 6. To be judged. If it is the 1st input shaft 5, it will transfer to Step S102, and if it is the 2nd input shaft 6, it will transfer to Step S106.

(When the low gear ratio gear is on the first input shaft)
In step S102, it is determined whether or not the torque distribution ratio γA <1 (the first clutch CA is incompletely engaged) to the first clutch CA on the low gear ratio side. If YES, the process proceeds to step S103. If NO, the process proceeds to step S105.

In step S103, it is determined that the first clutch CA is incompletely engaged and is not traveling only on the first input shaft 5 side on the low gear ratio side (the transmission input torque is the first, second clutch CA, Distributed to CB).
Therefore, in order to increase the engine brake, the transmission torque on the first input shaft 5 side on the low gear ratio side is increased. That is, in order to increase the torque distribution ratio γA of the first clutch CA, the torque distribution ratio increase rate ΔγA of the first clutch CA is calculated from the difference between the vehicle deceleration current value G and the engine brake under-determination threshold value GL, and step S104. Migrate to

  In step S104, the torque distribution ratio γA of the first clutch CA on the low gear ratio side is increased, and the torque distribution ratio γB = (1−γA) of the second clutch CB on the high gear ratio side is decreased. As a result, the engine torque input via the low gear position, that is, the first clutch CA is increased to increase the engine brake, and the control is terminated.

In step S105, it is determined that the first clutch CA is completely engaged and the vehicle is traveling only on the first input shaft 5 side. Therefore, the current gear position is on the first input shaft 5. In the current gear stage (on the first input shaft 5) and the gear stage being pre-shifted (on the second input shaft 6), the current gear stage on the first input shaft 5 has a lower gear ratio (steps S101 → S102). ).
In order to increase the engine brake from this state, it is necessary to achieve a lower gear position. On the other hand, the gear stage pre-shifted on the second input shaft 6 has a higher gear ratio than the current gear stage on the first input shaft 5.
For this reason, the shift stage pre-shifted on the second input shaft 6 is changed, and a shift stage that is one stage lower than the current shift stage on the first input shaft 5 is engaged to make a change request to the second clutch CB. Is output to end the control.

(When the low gear ratio gear is on the second input shaft)
In step S106, it is determined whether or not the torque distribution ratio γB <1 (the second clutch CB is incompletely engaged) to the second clutch CB on the low gear ratio side. If YES, the process proceeds to step S107. If NO, the process proceeds to step S109.

In step S107, it is determined that the second clutch CB is incompletely engaged and is not traveling only on the second input shaft 6 side on the low gear ratio side (the transmission input torque is determined by the first and second clutches CA, CB). Distributed).
Therefore, in order to increase the engine brake, the transmission torque on the second input shaft 6 side on the low gear ratio side is increased. That is, in order to increase the torque distribution ratio γB of the second clutch CB, the torque distribution ratio increase rate ΔγB of the second clutch CB is calculated from the difference between the vehicle deceleration current value G and the engine brake under-determination threshold GL, and step S108. Migrate to

  In step S108, the torque distribution ratio γB of the second clutch CB on the low gear ratio side is increased, and the torque distribution ratio γA = (1−γB) of the first clutch CA on the high gear ratio side is decreased. As a result, the engine torque input via the second clutch CB is increased to increase the engine brake, and the control is terminated.

In step S109, it is determined that the second clutch CB is completely engaged and the vehicle is traveling only on the second input shaft 6 side. Therefore, the current gear position is on the second input shaft 6. In the current gear stage (on the second input shaft 6) and the gear stage being pre-shifted (on the first input shaft 5), the current gear stage on the second input shaft 6 has a lower gear ratio (steps S101 → S106). ).
In order to increase the engine brake from this state, it is necessary to achieve a lower gear position. On the other hand, the gear stage that is preshifted on the first input shaft 5 has a higher gear ratio than the current gear stage on the second input shaft 6.
Therefore, the shift stage pre-shifted on the first input shaft 5 is changed, and a shift stage that is lower by one stage than the current shift stage on the second input shaft 6 is engaged, and a change request to the first clutch CA is made. Is output to end the control.

[Deceleration reduction processing (engine brake reduction processing)]
FIG. 6 is a flowchart showing the flow of deceleration reduction processing (engine brake reduction processing).

  In step S201, of the current gear stage and the gear stage engaged by the preshift, it is determined whether the gear stage with the higher gear ratio is engaged with the first or second input shaft 5 or 6. To be judged. If it is the 1st input shaft 5, it will transfer to Step S202, and if it is the 2nd input shaft 6, it will transfer to Step S206.

(When the high gear ratio gear is on the first input shaft)
In step S202, it is determined whether or not the torque distribution ratio γA <1 (the first clutch CA is incompletely engaged) to the first clutch CA on the high gear ratio side. If YES, the process proceeds to step S203. If NO, the process proceeds to step S205.

In step S203, it is determined that the first clutch CA is not completely engaged and is not traveling only on the first input shaft 5 side on the high gear ratio side (the transmission input torque is the first and second clutches CA, CB). Distributed).
Therefore, in order to reduce the engine brake, the transmission torque on the first input shaft 5 side on the high gear ratio side is increased. That is, in order to increase the torque distribution ratio γA of the first clutch CA, the torque distribution ratio increase rate ΔγA of the first clutch CA is calculated from the difference between the vehicle deceleration current value G and the engine brake excess determination threshold GH, and step S204. Migrate to

  In step S204, the torque distribution ratio γA of the first clutch CA on the high gear ratio side is increased, and the torque distribution ratio γB = (1−γA) of the second clutch CB on the high gear ratio side is decreased. As a result, the engine torque input via the high gear ratio side, that is, the first clutch CA is increased to decrease the engine brake, and the control is terminated.

In step S205, it is determined that the first clutch CA is completely engaged and the vehicle is traveling only on the first input shaft 5 side. Therefore, the current gear position is on the first input shaft 5. In the current gear stage (on the first input shaft 5) and the gear stage being pre-shifted (on the second input shaft 6), the current gear stage on the first input shaft 5 has a higher gear ratio (steps S201 → S202). ).
In order to reduce the engine brake from this state, it is necessary to achieve a higher gear. On the other hand, the gear stage preshifted on the second input shaft 6 has a lower gear ratio than the current gear stage on the first input shaft 5.
For this reason, the shift stage pre-shifted on the second input shaft 6 is changed, and a shift stage that is one stage higher than the current shift stage on the first input shaft 5 is engaged to make a change request to the second clutch CB. Is output to end the control.

(When the high gear ratio gear is on the second input shaft)
In step S206, it is determined whether or not the torque distribution ratio γB <1 (the second clutch CB is incompletely engaged) to the second clutch CB on the high gear ratio side. If YES, the process proceeds to step S207. If NO, the process proceeds to step S209.

In step S207, it is determined that the second clutch CB is not completely engaged and is not traveling only on the second input shaft 6 side on the high gear ratio side (the transmission input torque is determined by the first and second clutches CA, CB). Distributed).
Therefore, in order to reduce the engine brake, the transmission torque on the second input shaft 6 side on the high gear ratio side is increased. That is, in order to increase the torque distribution ratio γB of the second clutch CB, the torque distribution ratio increase rate ΔγB of the second clutch CB is calculated from the difference between the vehicle deceleration current value G and the engine brake excess determination threshold GH, and step S208. Migrate to

  In step S208, the torque distribution ratio γB of the second clutch CB on the high gear ratio side is increased, and the torque distribution ratio γA = (1−γB) of the first clutch CA on the low gear ratio side is decreased. Thereby, the engine torque input via the high gear ratio side, that is, the second clutch CB is increased to decrease the engine brake, and the control is terminated.

In step S209, it is determined that the second clutch CB is completely engaged and the vehicle is traveling only on the second input shaft 6 side. Therefore, the current gear position is on the second input shaft 6. In the current gear stage (on the second input shaft 6) and the gear stage being pre-shifted (on the first input shaft 5), the current gear stage on the second input shaft 6 has a higher gear ratio (steps S201 → S206). ).
In order to reduce the engine brake from this state, it is necessary to achieve a higher gear. On the other hand, the gear stage pre-shifted on the first input shaft 5 has a lower gear ratio than the current gear stage on the second input shaft 6.
Therefore, the shift stage that has been preshifted on the first input shaft 5 is changed, and a shift stage that is one stage higher than the current shift stage on the second input shaft 6 is engaged, and a change request to the first clutch CA is made. Is output to end the control.

[Change over time in deceleration reduction processing (engine brake increase processing)]
FIG. 7 is a time chart of the deceleration reduction process (engine brake increase process of FIG. 6) during the third speed traveling. It is assumed that the accelerator is already released on the time chart and the engine is braked. Further, in this time chart, the current shift speed (the third gear G3) is on the first input shaft 5, and the shift speed pre-shifted on the second input shaft 6 is the fourth speed (more than the current shift speed). 1 shift step).

(Time t0)
At time t0, the vehicle is downhill at the third speed, the accelerator is released, and the engine brake is applied. The road gradient is constant and descends with a constant slope. Therefore, the vehicle deceleration -G is also constant, and the transmission torque of the first clutch CA that transmits torque of the third speed gear G3 is also constant. At this time, the second clutch CB is not transmitting torque.

(Time t1)
At time t1, the value of the road surface gradient approaches zero, and the road surface inclination becomes gentle. Since the driving wheel and the engine are directly connected by the third gear G3, engine braking occurs and the vehicle deceleration -G increases.

(Time t2)
At time t2, the road surface gradient becomes zero and the inclination becomes zero. Further, the vehicle acceleration G falls below the engine brake excess determination threshold value between times t2 and t3, and engine brake reduction control (step S200) is executed.

(Time t3)
At time t3, the torque distribution ratio γA of the first clutch CA starts decreasing, the torque distribution ratio γB of the second clutch CB starts increasing, and the first and second clutches CA and CB are switched.

(Time t4)
At time t4, the torque distribution ratio γA of the first clutch CA is zero, the torque distribution ratio γB of the second clutch CB is 1, and torque transmission is performed only by the second clutch CB. As a result, the engine brake is reduced as compared with the third speed traveling, and the vehicle deceleration -G is also within the range of the thresholds GL and GH.

[Effect of the embodiment of the present application]
(1) The input shafts 5 and 6, the output shaft 15 provided in parallel to the input shafts 5 and 6, and the torque transmission between the input shafts 5 and 6 and the output shaft 15 are provided for each of a plurality of shift stages. In a control device for an automatic transmission having transmission gears G1 to G6 to be performed and an automatic MT controller 47 (control means) for engaging and releasing the transmission gears,
The automatic MT controller 47 detects the vehicle deceleration -G when torque is being transmitted to the drive wheels via the current gear and the accelerator is released, and the vehicle deceleration -G is a predetermined deceleration. If the excess threshold value is greater than GH, a deceleration reduction control is executed to reduce the torque transmission amount at the current shift stage and increase the torque transmission amount at a shift stage higher than the current shift stage. When G is smaller than the predetermined deceleration under threshold −GL, or when the vehicle accelerates while the accelerator is released, the torque transmission amount at the current shift speed is reduced and the torque at the shift speed lower than the current shift speed is reduced. Deceleration increasing control for increasing the transmission amount is executed.

  As a result, even in a stepped transmission that can obtain only a stepped gear ratio, the difference between the deceleration due to engine braking and the vehicle deceleration current value is reduced when the accelerator is released, and the stepped transmission is Even you can get the proper engine brake.

  (2) A control apparatus for a twin-clutch automatic transmission having a first clutch CA and a second clutch CB, wherein the input shaft is composed of a first input shaft 5 and a second input shaft 6, and the first input shaft 5 is connected to the first clutch CA, the second input shaft 6 is connected to the second clutch CB, and among the transmission gears, the odd-numbered shift stages G1, G3, G5 are distributed to the first input shaft 5, and the even-numbered shift stage. G2, G4, and G6 are distributed to the second input shaft 6, and the control device changes the torque transmission amount TA (T · γA) of the first clutch CA and the torque transmission amount TB (T · γB) of the second clutch CB. Thus, the deceleration reduction control and the deceleration increase control are executed.

  Thereby, even in the twin clutch type automatic transmission as in the embodiment of the present invention, the same operational effect as the above (1) can be obtained.

  (3) The automatic MT controller 47 increases the difference between the vehicle deceleration −G and the excessive deceleration threshold −GH or the difference between the vehicle deceleration −G and the excessive deceleration threshold −GL as the first and second The change speed of the torque transmission amount of the clutches CA and CB is increased. Thereby, an engine brake can be generated appropriately and promptly.

  (4) The automatic MT controller 47 performs control so that the sum of the torque transmission amount T · γA of the first clutch CA and the torque transmission amount T · γB of the second clutch CB is equal to the torque T input to the transmission. It was decided to. Thereby, it is possible to prevent the driving force from being lost.

(Other examples)
As mentioned above, although the control apparatus of the automatic transmission of this invention has been demonstrated based on the Example, it is not restricted to these Examples about a concrete structure, The invention which concerns on each claim of a claim Design changes and additions are allowed without departing from the gist.

1 is an overall system diagram of a twin clutch type automatic manual transmission to which a control device for an automatic transmission of the present application is applied. FIG. 5 is a hydraulic circuit diagram of an actuator hydraulic module and a clutch hydraulic module when a sequence solenoid is off. FIG. 3 is a hydraulic circuit diagram of an actuator hydraulic module and a clutch hydraulic module when a sequence solenoid is On. It is a main flow of engine brake control processing. It is a flowchart which shows the flow of a deceleration increase process (engine brake increase process). It is a flowchart which shows the flow of a deceleration reduction process (engine brake reduction process). It is a time chart of the deceleration reduction process (engine brake increase process of FIG. 6) at the time of 3rd speed driving | running | working.

Explanation of symbols

CA 1st clutch CB 2nd clutch G1 1st gear G2 2nd gear G3 3rd gear G4 4th gear G6 6th gear GR Reverse gear 28 1-R synchronous meshing mechanism 29 3-5 synchronous meshing mechanism 37 6-N synchronous Meshing mechanism 38 2-4 synchronous meshing mechanism 41 3-5 shift fork 42 1-R shift fork 43 6-N shift fork 44 2-4 shift fork 45 actuator unit 46 clutch hydraulic module 48 first shift rod 49 3-5 shift Bracket 50 3-5 shift actuator 51 2nd shift rod 52 1-R shift actuator 53 6-N shift actuator 54 2-4 shift actuator 55 3-5 shift position sensor 56 1-R shift position sensor 57 6-N shift position Sensor 58 2-4 Shift position sensor 59 Actuator Hydraulic module 71-74 actuator solenoid 75 sequence solenoid 76 the spool 77 even, odd-shift-stage pressure solenoid 81 first, second clutch control pressure solenoid 83, 84 first, second clutch pressure sensor 85 the line pressure solenoid

Claims (4)

An input shaft;
An output shaft provided parallel to the input shaft;
A transmission gear that is provided for each of a plurality of shift speeds and transmits torque between the input shaft and the output shaft;
A control device for an automatic transmission having control means for engaging and releasing the transmission gear;
The control means includes
Detects vehicle deceleration when the accelerator is released when torque is being transmitted to the drive wheels via the current gear stage,
When the vehicle deceleration is larger than a predetermined deceleration excessive threshold, the deceleration reduction decreases the torque transmission amount at the current shift stage and increases the torque transmission amount at a shift stage higher than the current shift stage. Execute control,
When the vehicle deceleration is smaller than a predetermined deceleration under threshold or when the vehicle accelerates while the accelerator is released, the torque transmission amount at the current shift stage is reduced and a shift lower than the current shift stage is performed. A control device for an automatic transmission, which executes deceleration increase control for increasing a torque transmission amount of a stage. The transmission control device according to claim 1 or 2,
A control device for a twin-clutch automatic transmission having a first clutch and a second clutch,
The input shaft is composed of a first input shaft and a second input shaft,
The first input shaft is connected to the first clutch, the second input shaft is connected to the second clutch;
Of the transmission gears, odd-numbered gears are distributed to the first input shaft, even-numbered gears are distributed to the second input shaft,
The control device executes the deceleration reduction control and the deceleration increase control by changing the torque transmission amount of the first clutch and the torque transmission amount of the second clutch. Control device. The control apparatus for an automatic transmission according to claim 2,
The control means changes the torque transmission amount of the first and second clutches as the difference between the vehicle deceleration and the over-deceleration threshold or the difference between the vehicle deceleration and the under-deceleration threshold increases. A control device for an automatic transmission characterized by increasing the speed. The control apparatus for an automatic transmission according to any one of claims 1 to 3,
The control means controls the automatic transmission so that the sum of the torque transmission amount of the first clutch and the torque transmission amount of the second clutch is equal to the torque input to the transmission. apparatus.

Images