JP6780199B2 - Control device for automatic transmission - Google Patents

Description

The present invention relates to a control device for an automatic transmission including an auxiliary transmission mechanism and a continuously variable transmission mechanism.

The technique of Patent Document 1 is known as a control device for an automatic transmission including an auxiliary transmission mechanism and a continuously variable transmission mechanism. In this publication, when the gear ratio of an automatic transmission (hereinafter referred to as a through gear ratio) obtained from both the gear ratio of the auxiliary transmission mechanism and the gear ratio of the continuously variable transmission mechanism is shifted, the auxiliary transmission mechanism is described. When upshifting is involved, the auxiliary transmission mechanism controls during power-on upshifting, which upshifts when the torque input from the engine side is positive torque, and upshifting when the torque input from the engine side is negative torque. The control at the time of power-off upshift is disclosed.

Japanese Unexamined Patent Publication No. 2010-209948

Here, since the start timing of the inertia phase is different between the power-on upshift and the power-off upshift, if the power-on or power-off determination is incorrect, the shift timing on the continuously variable transmission side and the shift timing on the auxiliary transmission mechanism side In some cases, the through gear ratio may change to the upshift side and the engine speed may decrease. When the engine speed drops, it is necessary to release the lockup clutch in order to avoid engine stall, which may affect the behavior of the vehicle and give the driver a sense of discomfort.

Focusing on the above problems, an object of the present invention is to provide a control device for an automatic transmission capable of suppressing fluctuations in vehicle behavior due to upshifting of an auxiliary transmission mechanism regardless of a power-on or power-off determination result. To do.

For this purpose, in the control device of the automatic transmission of the present invention, an automatic transmission having a main transmission mechanism capable of steplessly changing the gear ratio, an auxiliary transmission mechanism having a plurality of fixed transmission stages, and the like.

The target gear ratio of the automatic transmission is calculated, and the gear ratio of the main transmission mechanism and the gear ratio of the auxiliary transmission mechanism are combined to achieve the target gear ratio of the main transmission mechanism and the auxiliary transmission mechanism. A controller for controlling the gear ratio is provided, and the controller determines whether the input torque of the automatic transmission is in the power-on state or the power-off state based on the torque information received from the engine, and determines whether the power-on state is in the power-on state. When the auxiliary transmission mechanism is upshifted, power-on upshift control is performed to shift from the torque phase to the inertia phase, and in the power-off state, torque is applied from the inertial phase when the auxiliary transmission mechanism is upshifted. Power-off upshift control to shift to the phase is performed, and the auxiliary transmission mechanism is upshifted at a low accelerator pedal opening. The auxiliary transmission mechanism at a high accelerator pedal opening at a speed higher than the first vehicle speed in which the first mode switching line is set. The vehicle speed range is below the second vehicle speed where the second mode switching line is set, and the target gear ratio during coast driving is equal to or higher than the input speed of the main transmission mechanism of the coast line and is low. Of the mode switching lines when the accelerator pedal is open, depending on the first mode switching line at the third vehicle speed where the lowest line and the coast line intersect when the auxiliary transmission mechanism selects the high side transmission stage. In the first region defined in the rotation speed range equal to or lower than the input rotation speed of the main transmission mechanism, when the auxiliary transmission mechanism is upshifted, the power-off upshift control is performed regardless of the torque information. And.

Therefore, regardless of the power-on or power-off determination result, it is possible to suppress a decrease in the engine speed due to the upshift of the auxiliary transmission mechanism, and by avoiding the release of the lockup clutch, it is possible to suppress fluctuations in vehicle behavior.

It is a schematic system diagram which shows the drive system of the vehicle of Example 1 and its whole control system. In the vehicle of the first embodiment, (a) is a schematic system diagram showing the drive system of the vehicle and its overall control system, and (b) is built in the V-belt type continuously variable transmission in the drive system of the vehicle. It is a fastening logic diagram of the clutch in the auxiliary transmission. This is an example of a shift map stored in the transmission controller of the first embodiment. FIG. 5 is a time chart showing a shift state when the vehicle of the first embodiment crosses a mode switching line when a low accelerator pedal is opened due to an increase in vehicle speed. It is a time chart which shows the shift state at the time of crossing the mode switching line at the time of a low accelerator pedal opening by the foot release of an accelerator pedal in the vehicle of a comparative example. It is a flowchart which shows the upshift processing by straddling the mode switching line of Example 1. FIG. FIG. 5 is a time chart showing a shift state when the vehicle of the first embodiment crosses a mode switching line when the accelerator pedal is opened due to the release of the accelerator pedal opening.

[Example 1]
FIG. 1 is a schematic system diagram showing a vehicle drive system of the first embodiment and an overall control system thereof. The vehicle of FIG. 1 is equipped with the engine 1 as a power source. The engine 1 is started by the starter motor 3. The engine 1 is driven and coupled to the drive wheels 5 via the automatic transmission 4 so as to be appropriately detachable.

The variator CVT of the automatic transmission 4 is a V-belt type continuously variable transmission mechanism consisting of a primary pulley 6, a secondary pulley 7, and a V-belt 8 (endless flexible member) spanned between these pulleys 6 and 7. .. The V-belt 8 adopts a configuration in which a plurality of elements are bundled by an endless belt, but the chain method or the like may be used and is not particularly limited. The primary pulley 6 is coupled to the crankshaft of the engine 1 via the torque converter T / C, and the secondary pulley 7 is coupled to the drive wheels 5 via the clutch CL and the final gear set 9 in sequence. In this embodiment, the elements (clutch, brake, etc.) that connect and disconnect the power transmission path are collectively referred to as a clutch. FIG. 1 conceptually shows the power transmission path, and the high clutch H / C, the reverse brake R / B, and the low brake L / B provided in the auxiliary transmission 31 described later are collectively referred to as a clutch. It is described as CL. When the clutch CL is engaged, the power from the engine 1 is input to the primary pulley 6 via the torque converter T / C, and then through the V-belt 8, the secondary pulley 7, the clutch CL and the final gear set 9, the drive wheels 5 Reach and drive.

During engine power transmission, the pulley V-groove width of the primary pulley 6 is reduced and the pulley V-groove width of the secondary pulley 7 is increased to increase the winding arc diameter between the V-belt 8 and the primary pulley 6 and at the same time the secondary. Reduce the diameter of the winding arc with the pulley 7. As a result, the variator CVT upshifts to the High side pulley ratio (High side gear ratio). When the upshift to the high gear ratio is performed to the limit, the gear ratio is set to the maximum gear ratio.

Conversely, by increasing the pulley V-groove width of the primary pulley 6 and reducing the pulley V-groove width of the secondary pulley 7, the winding arc diameter between the V-belt 8 and the primary pulley 6 is reduced, and at the same time, the secondary pulley 7 and the secondary pulley 7. Increase the diameter of the winding arc. As a result, the variator CVT downshifts to the Low side pulley ratio (Low side gear ratio). When the downshift to the low gear ratio is performed to the limit, the gear shift is set to the minimum gear ratio.

The variator CVT has a primary rotation speed sensor 6a that detects the rotation speed of the primary pulley 6 and a secondary rotation speed sensor 7a that detects the rotation speed of the secondary pulley 7, and the rotation speed detected by both rotation speed sensors. The actual CVT gear ratio Iv is calculated based on the above, and the hydraulic pressure of each pulley is controlled so that the actual CVT gear ratio Iv becomes the target CVT gear ratio Iv *.

The engine controller 22 controls the output of the engine 1, and the transmission controller 24 uses the oil from the mechanical oil pump O / P driven by the engine as a medium to control the speed change of the variator CVT and the speed change control of the auxiliary transmission 31. It controls the engagement and release of the clutch CL.

FIG. 2A is a schematic system diagram showing the vehicle drive system of the first embodiment and its overall control system, and FIG. 2B is built into the automatic transmission 4 in the vehicle drive system of the first embodiment. It is a fastening logic diagram of the clutch CL (specifically, H / C, R / B, L / B) in the auxiliary transmission 31. As shown in FIG. 2A, the auxiliary transmission 31 rotatably supports the composite sun gears 31s-1 and 31s-2, the inner pinion 31pin, the outer pinion 31pout, the ring gear 31r, and the pinion 31pin, 31pout. It is composed of a labinho type planetary gear set consisting of a carrier 31c.

Of the composite sun gears 31s-1 and 31s-2, the sun gear 31s-1 is coupled to the secondary pulley 7 to act as an input rotation member, and the sun gear 31s-2 is placed coaxially with the secondary pulley 7 but rotates freely. Try to get.

The inner pinion 31pin is meshed with the sun gear 31s-1, and the inner pinion 31pin and the sun gear 31s-2 are meshed with the outer pinion 31pout, respectively.
The outer pinion 31pout meshes with the inner circumference of the ring gear 31r and couples the carrier 31c to the final gear set 9 so as to act as an output rotating member.
The carrier 31c and the ring gear 31r can be appropriately coupled by the high clutch H / C which is the clutch CL, the ring gear 31r can be appropriately fixed by the reverse brake R / B which is the clutch CL, and the sun gear 31s-2 can be appropriately fixed by the clutch CL. It can be fixed appropriately by a certain low brake L / B.

In the auxiliary transmission 31, the high clutch H / C, the reverse brake R / B, and the low brake L / B are fastened in the combination indicated by the circle in FIG. 2 (b), and the others are × in FIG. 2 (b). By releasing as indicated by the mark, the forward first speed, the second speed, and the reverse gear can be selected. When the high clutch H / C, reverse brake R / B and low brake L / B are all released, the auxiliary transmission 31 is in a neutral state without power transmission, and when the low brake L / B is engaged in this state, the auxiliary transmission 31 is in a neutral state. The transmission 31 is in the forward 1st speed selection (deceleration) state, and when the high clutch H / C is engaged, the auxiliary transmission 31 is in the forward 2nd speed selection (direct connection) state, and when the reverse brake R / B is engaged, the auxiliary transmission 31 is in the forward 1st speed selection (deceleration) state. The transmission 31 is in the reverse selection (reverse) state.

The automatic transmission 4 in FIG. 2A releases the variator CVT (secondary pulley) by releasing all clutches CL (H / C, R / B, L / B) and neutralizing the auxiliary transmission 31. The 7) and the drive wheel 5 can be separated.

The automatic transmission 4 in FIG. 2 (a) is controlled by using oil from an engine-driven mechanical oil pump O / P as an operating medium, and the transmission controller 24 has a line pressure solenoid 35 and a lockup solenoid 36. , Primary pulley pressure solenoid 37-1, secondary pulley pressure solenoid 37-2, low brake pressure solenoid 38, high clutch pressure & reverse brake pressure solenoid 39 and switch valve 41 to control the control of the variator CVT as follows. To do. The transmission controller 24 has a signal from the accelerator pedal opening sensor 27 (see FIG. 1) that detects the accelerator pedal depression amount (accelerator pedal opening) APO, and a signal from the vehicle speed sensor 32 that detects the vehicle speed VSP. And the signal from the acceleration sensor 33 that detects the vehicle acceleration / deceleration G is input.

The line pressure solenoid 35 responds to a command from the transmission controller 24 and adjusts the oil from the mechanical oil pump O / P to the line pressure PL corresponding to the vehicle required driving force. The lockup solenoid 36 responds to a lockup command from the transmission controller 24 and directs the line pressure PL to the torque converter T / C as appropriate, so that the torque converter T / C can be moved between the input / output elements as required. Put it in a directly connected lockup state. The primary pulley pressure solenoid 37-1 adjusts the line pressure PL to the primary pulley pressure in response to the CVT gear ratio command from the transmission controller 24, and supplies this to the primary pulley 6, thereby V of the primary pulley 6. The groove width and the V-groove width of the secondary pulley 7 are controlled so that the CVT gear ratio matches the command from the transmission controller 24 to realize the CVT gear ratio command from the transmission controller 24. The secondary pulley pressure solenoid 37-2 adjusts the line pressure PL to the secondary pulley pressure in response to the clamping force command from the transmission controller 24, and supplies this to the secondary pulley 7, so that the secondary pulley 7 becomes the V-belt 8 Clamp so as not to slip.
The low brake pressure solenoid 38 is engaged by supplying the line pressure PL as the low brake pressure to the low brake L / B when the transmission controller 24 issues the first speed selection command of the auxiliary transmission 31. , Realize the 1st speed selection command.
The high clutch pressure & reverse brake pressure solenoid 39 is a switch valve that uses the line pressure PL as the high clutch pressure & reverse brake pressure when the transmission controller 24 issues the second speed selection command or the backward selection command of the auxiliary transmission 31. Supply to 41.

At the time of the 2nd speed selection command, the switch valve 41 directs the line pressure PL from the solenoid 39 to the high clutch H / C as the high clutch pressure, and by engaging this, the 2nd speed selection command of the auxiliary transmission 31 is issued. Realize.
At the time of the reverse selection command, the switch valve 41 directs the line pressure PL from the solenoid 39 to the reverse brake R / B as the reverse brake pressure, and by fastening this, the reverse selection command of the auxiliary transmission 31 is realized.

[About shift control processing]
Next, the shift control process will be described. FIG. 3 is an example of a shift map stored in the transmission controller 24 of the first embodiment. The transmission controller 24 controls the automatic transmission 4 according to the driving state of the vehicle (vehicle speed VSP, primary rotation speed Npri, accelerator pedal opening APO in the first embodiment) with reference to this shift map. In this shift map, the operating point of the automatic transmission 4 is defined by the vehicle speed VSP and the primary rotation speed Npri (or turbine rotation speed Nt). The inclination of the line connecting the operating point of the automatic transmission 4 and the zero point in the lower left corner of the shift map is the overall gear ratio obtained by multiplying the gear ratio Iv of the variator CVT by the gear ratio Isub of the auxiliary transmission 31. It corresponds to the gear ratio Ith, hereinafter referred to as "through gear ratio").

In this shift map, a shift line is set for each accelerator pedal opening APO, as in the shift map of the conventional belt-type continuously variable transmission, and the shift of the automatic transmission 4 depends on the accelerator pedal opening APO. It is performed according to the selected transmission line. When the operating point of the current automatic transmission 4 crosses various shift lines set in the shift map, the shift is started from the current shift state to a new shift state set by crossing the shift line.

When the automatic transmission 4 is in the low speed mode, the automatic transmission 4 is obtained by setting the gear ratio of the variator CVT to the lowest gear ratio and the gear ratio of the low speed mode lowest line and the variator CVT to the highest gear ratio. It is possible to shift between the highest lines in the low speed mode. On the other hand, when the automatic transmission 4 is in the high-speed mode, the automatic transmission 4 sets the gear ratio of the variator CVT to the lowest gear ratio and sets the gear ratio of the high-speed mode lowest line and the variator CVT to the highest gear ratio. It is possible to shift between the highest high speed lines in the obtained high speed mode.

The gear ratio of each gear of the auxiliary transmission 31 is such that the gear ratio corresponding to the highest line in low speed mode (highest gear ratio in low speed mode) corresponds to the lowest gear ratio in high speed mode (lowest gear ratio in high speed mode). Is set to be smaller than.

Further, on this shift map, a plurality of mode switching shift lines for shifting the auxiliary transmission 31 are set. If the driver does not depress the accelerator pedal significantly, a 1-2 upshift is performed on the mode switching shift line when the accelerator pedal is open. This is because when the accelerator pedal is opened, the input torque to the auxiliary transmission 31 is small even if the gear ratio of the variator CVT is large, and the shift shock when shifting the auxiliary transmission 31 is suppressed. The mode switching shift line when the low accelerator pedal is opened has a portion set to be lower than the lowest line in the high speed mode. This is an area where it is difficult to secure the speed change speed of the variator CVT because the number of revolutions including the engine 1 is low as a whole, so 1-2 upshifts are started from this area and the variator CVT This is to secure the shift time.

On the other hand, the mode switching line when the high accelerator pedal is opened is set slightly lower than the highest line in the low speed mode. The reason why the mode switching shift line when the accelerator pedal is open is set in this way is that the smaller the gear ratio of the variator CVT, the smaller the input torque to the auxiliary transmission 31, and the shift shock when shifting the auxiliary transmission 31. This is because it can be suppressed. The mode switching shift line at the time of opening the high accelerator pedal has a portion set to the lower side than the highest line in the low speed mode. This is also actually set in consideration of the speed change speed of the variator CVT and the progress speed of the inertia phase of the auxiliary transmission 31.

When the operating point of the automatic transmission 4 crosses the mode switching shift line when the accelerator pedal is open low or when the accelerator pedal is high, the transmission controller 24 performs coordinated shifting with both the variator CVT and the auxiliary transmission 31. , Switch between high speed mode and low speed mode.

FIG. 4 is a time chart showing a shift state when the vehicle of the first embodiment crosses the mode switching line at the time of opening the low accelerator pedal due to an increase in the vehicle speed. When the target through gear ratio Ith * is not changed and the mode switching line is crossed when the accelerator pedal is open, the auxiliary transmission 31 starts an upshift and the variator CVT starts a downshift. At this time, the transmission controller 24 receives engine torque information from the engine controller 22 and is either in the power-on state (hereinafter referred to as P / ON) or in the power-off state (hereinafter referred to as P / OFF). When it is P / ON, when the auxiliary transmission 31 is upshifted, the engine blow-up due to the torque phase is prevented, and then the inertia phase is started. On the other hand, when P / OFF, there is no possibility that the engine 1 will blow up, so when the auxiliary transmission 31 is upshifted, it starts from the inertia phase. That is, the timing at which the inertia phase starts differs between P / ON and P / OFF.

Next, in the vicinity of torque zero where it is difficult to determine P / ON and P / OFF, the determination of P / ON and P / OFF may be incorrect. If it is erroneously determined to be P / ON in the P / OFF state, the inertia phase will start at the time of the torque phase, and the shift start timing of the variator CVT will be delayed from the progress of the shift of the auxiliary transmission 31. Then, the through gear ratio Ith shifts to the High side, and the engine speed Ne decreases, so that it is necessary to release the lockup clutch, which may lead to deterioration of fuel efficiency.

Therefore, in the first embodiment, the configurations listed below are adopted in the area where P / ON and P / OFF may be erroneously determined. Here, the area where P / ON and P / OFF may be erroneously determined is defined. As shown in the shift map of FIG. 3, from the viewpoint of the vehicle speed VSP, the definition of the mode switching line at the time of opening the high accelerator pedal is defined as the vehicle speed V2 or less at which the definition of the mode switching line at the time of opening the low accelerator pedal is started. It was decided that the vehicle speed would be V1 (<V2) or higher. Next, from the viewpoint of the turbine rotation speed Nt, the coast line is in the region on the higher rotation speed side than the set rotation speed, and among the mode switching lines at the time of opening the low accelerator pedal, the highest speed mode lowest line and the coast line. It is decided that the turbine speed is in the region of N1 or less, which is slightly higher than the turbine speed Nt defined by the mode switching line when the accelerator pedal is opened at the vehicle speed V3 where Here, among the above-mentioned regions, the region surrounded by V3 and V2 is referred to as Z1, and the region surrounded by V1 and B3 is referred to as Z2. When it is in either Z1 or Z2 area, it is an area where erroneous determination of P / ON and P / OFF is likely to occur.

Then, in the areas Z1 and Z2 where P / ON and P / OFF may be erroneously determined, it is always determined as P / OFF. As a result, it is possible to avoid the progress of shifting in the torque phase. Since the torque is near zero, the engine speed does not increase even if it is determined to be P / OFF.

FIG. 5 is a time chart showing a shift state when the vehicle of the comparative example crosses the mode switching line when the accelerator pedal is opened due to the release of the accelerator pedal. In this case, the target gear ratio is also changed to the upshift side by changing the accelerator pedal opening APO. At this time, the target through gear ratio Ith * is also changed, and the variator CVT initially upshifts accordingly, but the auxiliary transmission 31 starts upshifting because it crosses the mode switching line when the accelerator pedal is open. , Variator CVT starts downshift. At this time, since the shift speed of the variator CVT is slow, if the downshift is performed after the upshift, the slew gear ratio shifts to the High side due to the delay in the shift of the variator CVT, and the engine speed decreases.

Therefore, in the first embodiment, in the regions Z1 and Z2, the change speed of the target through gear ratio Ith * is slowed down, the cooperative shift is interrupted, and the shift of the auxiliary transmission 31 and the shift of the variator CVT are executed independently. It was decided to. Therefore, since the target through gear ratio Ith * is slowed down, the variator CVT does not shift up so much at the first stage, so when the downshift is performed when the mode switching line is crossed when the accelerator pedal is open. The amount of change can be reduced. Therefore, even when the speed change speed of the variator CVT is slow, the downshift delay can be suppressed. In addition, since the cooperative shift is stopped and the auxiliary transmission 31 and the variator CVT are shifted independently, the shift on the variator CVT side can be started immediately without waiting for the start of the inertia phase of the auxiliary transmission 31. It is possible to avoid a shift of the through gear ratio Ith to the High side. Therefore, even if the shift speed of the target through gear ratio Ith * is slowed down, the downshift of the variator CVT can be sufficiently achieved when the inertia phase of the auxiliary transmission 31 ends. Since the shifting speed is slower in the region Z1, it was decided to set the shifting speed of the target through gear ratio Ith * even slower than in the region Z2.

FIG. 6 is a flowchart showing an upshift process by straddling the mode switching line of the first embodiment.
In step S1, it is determined whether or not the operating point of the automatic transmission 4 is in the area Z1 or Z2. If YES, the process proceeds to step S5, and if NO, the process proceeds to step S2.
In step S2, it is determined whether it is P / ON or P / OFF, and if it is P / ON, the process proceeds to step S3 to execute the P / ON upshift process. On the other hand, in the case of P / OFF, the process proceeds to step S4 to execute the P / OFF upshift process. In areas other than Z1 or Z2, it is difficult for erroneous determination of P / ON or P / OFF to occur, so normal processing is performed.

In step S6, the shifting speed when setting the target through gear ratio Ith * is set to VG1.
In step S7, the shifting speed when setting the target through gear ratio Ith * is set to VG2, which is faster than VG1.
In step S8, the upshift processing at low rotation speed is executed. Specifically, the P / OFF is set regardless of the information content from the engine controller 22, the cooperative shift is stopped, and the independent shift is performed.

FIG. 7 is a time chart showing a shift state when the vehicle of the first embodiment crosses the mode switching line at the time of low accelerator pedal opening due to the release of the accelerator pedal opening. When the driver releases the accelerator pedal, the target through gear ratio Ith * is changed. At this time, the gear shifting speed is set to be slower than the target through gear ratio Ith * (one-dot chain line shown in the comparative example in FIG. 7) set in other regions. Moreover, since the coordinated shift is stopped, the variator CVT immediately starts the shift. At first, the upshift is performed, but since the shift speed is set to be slow, the upshift is not performed so much. Further, when the auxiliary transmission 31 starts the upshift, the upshift is performed by P / OFF, so that the shift timing does not vary. Further, after the auxiliary transmission 31 starts the upshift, the variator CVT starts the downshift, but since the variator CVT does not upshift so much, the downshift amount can be reduced. In addition, since the variator CVT is not coordinated, the variator CVT quickly downshifts as if the auxiliary transmission 31 has started the inertia phase, so the variator CVT downshifts before the upshift of the auxiliary transmission 31 is completed. Since it is completed, it is possible to suppress a decrease in the engine speed Ne.

As described above, in Example 1, the following effects can be obtained.
(1) An automatic transmission 4 having a variator CVT (main transmission mechanism) capable of steplessly changing the gear ratio, an auxiliary transmission 31 (auxiliary transmission mechanism) having a plurality of fixed transmission stages, and an automatic transmission. Calculate the target through gear ratio Ith * (target gear ratio), and combine the variator gear ratio Iv of the variator CVT and the gear ratio Isub of the auxiliary transmission 31 to achieve the target through gear ratio Iv *. A transmission controller 24 that controls the gear ratio of the transmission 31 is provided, and the transmission controller 24 is in a power-on state or a power-off state in the input torque of the automatic transmission 4 based on the torque information received from the engine 1. Judging whether or not it is, when the power is on, when the auxiliary transmission 31 is upshifted, the power on upshift control is performed to shift from the torque phase to the inertia phase, and when the power is off, the auxiliary transmission is controlled. A first mode in which power-off upshift control is performed to shift from the inertia phase to the torque phase when 31 is upshifted, and the mode switching line at low accelerator pedal opening (the auxiliary transmission mechanism is upshifted at low accelerator pedal opening). V1 (first vehicle speed) or higher where the switching line) is set, and V2 where the mode switching line at high accelerator pedal opening (second mode switching line that upshifts the auxiliary transmission mechanism at high accelerator pedal opening) is set. In the vehicle speed range below (second vehicle speed), the target through gear ratio Ith * during coast driving is equal to or higher than the set turbine speed (main transmission mechanism input speed) of the coast line, and the low accelerator pedal is open. Of the speed mode switching lines, the low in V3 (third vehicle speed) where the high speed mode lowest line (the lowest line when the auxiliary transmission mechanism selects the high transmission stage) and the coast line intersect. When upshifting the auxiliary transmission 31 in the regions Z1 and Z2 (first region) defined in the rotation speed range of the turbine rotation speed N1 or less according to the mode switching line when the accelerator pedal is open, regardless of the torque information. Power off and upshift control is performed.
Therefore, regardless of the power-on or power-off determination result, the decrease in engine speed Ne due to the upshift of the auxiliary transmission 31 can be suppressed, and by avoiding the release of the lockup clutch, fluctuations in vehicle behavior are suppressed. it can.

(2) When the transmission controller 24 upshifts the auxiliary transmission 31 in the regions Z1 and Z2, the change speed of the target through gear ratio Ith * is slower than the change speed in the regions other than the regions Z1 and Z2.
Therefore, even when the speed change speed of the variator CVT is slow, it is possible to suppress a decrease in the engine speed Ne.

(3) The transmission controller 24 further slows down the change speed of the target through gear ratio Ith * in the region Z2 (in the first region and below the third vehicle speed).
Therefore, even when the speed change speed of the variator CVT is even slower, it is possible to suppress a decrease in the engine speed Ne.

1 engine (power source)
2 Electric motor (power source)
3 Starter motor
4 V belt type continuously variable transmission
5 drive wheels
6 Primary pulley
7 Secondary pulley
8 V belt
CVT variator (continuously variable transmission)
T / C torque converter
9 Final gear set
19 Accelerator pedal
22 engine controller
24 transmission controller
27 Accelerator pedal opening sensor
O / P oil pump
31 Sub-transmission
CL clutch
H / C high clutch
R / B reverse brake
L / B low brake
32 Vehicle speed sensor

Claims (3)

An automatic transmission having a main transmission mechanism capable of steplessly changing the gear ratio and an auxiliary transmission mechanism having a plurality of fixed transmission stages.
The target gear ratio of the automatic transmission is calculated, and the gear ratio of the main transmission mechanism and the gear ratio of the auxiliary transmission mechanism are combined to achieve the target gear ratio of the main transmission mechanism and the auxiliary transmission mechanism. A controller that controls the gear ratio and
With
The controller determines whether the input torque of the automatic transmission is in the power-on state or the power-off state based on the torque information received from the engine, and when the power-on state, upshifts the auxiliary transmission mechanism. At that time, power-on upshift control is performed to shift from the torque phase to the inertia phase, and in the power-off state, power-off upshift control is performed to shift from the inertia phase to the torque phase when upshifting the auxiliary transmission mechanism. ,
A second mode switching line for upshifting the auxiliary transmission mechanism at a high accelerator pedal opening is set at a speed equal to or higher than the first vehicle speed in which the first mode switching line for upshifting the auxiliary transmission mechanism is set at a low accelerator pedal opening. Of the mode switching lines at the time of low accelerator pedal opening, which is in the vehicle speed range equal to or lower than the second vehicle speed and is equal to or higher than the main transmission mechanism input rotation speed of the coast line in which the target gear ratio during coast driving is set. The number of revolutions equal to or less than the input revolution of the main transmission according to the first mode switching line at the third vehicle speed at which the lowest line and the coast line intersect when the auxiliary transmission mechanism selects the high shift stage. A control device for an automatic transmission, characterized in that when the auxiliary transmission mechanism is upshifted in a first region defined by a region, the power-off upshift control is performed regardless of the torque information. In the control device for the automatic transmission according to claim 1,
The controller is an automatic transmission characterized in that when the auxiliary transmission mechanism is upshifted in the first region, the change speed of the target gear ratio is slower than the change speed when outside the first region. Control device. In the control device for the automatic transmission according to claim 2.
The controller is a control device for an automatic transmission, characterized in that the speed of change is further reduced when the speed is within the first region and is equal to or lower than the third vehicle speed.

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