JPH05240335A - Transmission controller for vehicle provided with continuously variable transmission with auxiliary transmission - Google Patents

Abstract

PURPOSE:To carry out control of vehicle condition at an optimum timing by carrying out control of vehicle condition based on the actual speed change action when the actual speed change action is judged based on the width change from a changed curve point of an output axial rotational speed after the speed change of the auxiliary transmission is judged. CONSTITUTION:In a transmission controller consisting of a belt continuously variable transmission(CVT), the transmission gear ratio of which is varied continuously by a hydraulic cylinder, and of an auxiliary transmission to be connected to a rear step of the CVT, which can be switched into a plurality of forward gear steps, a speed change judgement means for judging the speed change of the auxiliary transmission and an output shaft rotational number detection means for detecting the output shaft rotational number of the CVT are provided. The speed change judgement means for detecting the actual speed change action of the auxiliary transmission based on the width change from a changed curve point of the detected output shaft rotational number, is provided. When the actual speed change action is judged by the speed change action judgement means after the speed change of the auxiliary transmission is judged by the speed change judgement means, the vehicle condition is controlled based on the actual speed change action by a vehicle condition control means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for a vehicle provided with a continuously variable transmission with an auxiliary transmission.

[0002]

2. Description of the Related Art In a vehicle equipped with an automatic transmission capable of switching to a plurality of forward gears, when the gears are switched, an actual gear shift operation is performed based on a change in an input shaft rotation speed of the automatic transmission or an engine rotation speed. Is determined and the vehicle state control based on the actual shift operation is performed, for example, the control for temporarily reducing the output torque of the engine thereafter is performed in order to mitigate the shift shock.
For example, the shift control device described in Japanese Patent Laid-Open No. 62-279144 is that.

[0003]

By the way, a sub-gear which can be switched to a plurality of forward gears similar to those of the above-described automatic transmission is provided after the belt type continuously variable transmission in which the gear ratio is continuously changed by the hydraulic cylinder. Even in a vehicle equipped with a continuously variable transmission of the type in which gears are connected, the vehicle state control at the time of shifting as described above is performed in order to mitigate the shift shock that occurs when the gear stage of the auxiliary transmission is changed. It is possible to apply the technology.

However, in the belt type continuously variable transmission, the thrust of the hydraulic cylinder is adjusted in order to maintain a predetermined target value by executing feedback control for obtaining the target engine rotation speed or the target gear ratio. It However, since the belt type continuously variable transmission has the property that the gear ratio changes as the transmission torque changes even if the thrust ratio of the hydraulic cylinder is the same, inertia torque is generated when the auxiliary transmission shifts. When the transmission torque of the belt type continuously variable transmission changes due to this, it is inevitable that the speed change ratio temporarily changes. Therefore, the engine speed or the input shaft speed changes due to inertia torque generated in connection with the actual shift of the auxiliary transmission, and the change tends to be delayed. For this reason, the actual start time of the gear shift operation detected based on the change in the engine rotation speed or the input shaft rotation speed, that is, the moment when the inertia phase is detected becomes inaccurate, and control for mitigating gear shift shock, for example, the engine. There is a drawback that the control for temporarily reducing the output torque for the duration of the inertia phase or releasing the lockup clutch cannot be executed at an appropriate timing. When it is not possible to execute the control for reducing such shift shock at an appropriate timing,
The shift shock may not be alleviated sufficiently and the drivability may be impaired.

The present invention has been made in view of the above circumstances. An object of the present invention is to accurately detect the start time point of the actual shift operation of the auxiliary transmission and to control the vehicle state at an appropriate timing. It is an object of the present invention to provide a shift control device for a vehicle, which is provided with a continuously variable transmission with an auxiliary transmission capable of executing the above.

[0006]

To achieve the above object, the gist of the present invention is to change the gear ratio steplessly by a hydraulic cylinder as shown in the gist of the invention of FIG. A continuously variable transmission including a belt type continuously variable transmission and a sub transmission that is connected to a rear stage of the belt type continuously variable transmission and is switched to a plurality of forward gears. And (a) a gear shift determination unit that determines the gear shift of the auxiliary transmission, and (b) an output shaft rotation speed detection unit that detects the output shaft rotation speed of the belt type continuously variable transmission,
(c) shift operation determining means for determining the actual shift operation based on the width of change from the inflection point of the output shaft rotational speed detected by the output shaft rotational speed detecting means, and (d) the shift determining means. After the shift of the auxiliary transmission is determined, when the actual shift operation is determined by the shift operation determination means, vehicle state control means for controlling the vehicle state based on the actual shift operation, To include.

[0007]

With this configuration, after the shift determining means determines the shift of the auxiliary transmission, the shift operation determining means determines the actual shift operation based on the range of change from the inflection point of the output shaft rotation speed. When it is determined that the vehicle state control means executes the vehicle state control based on the actual shift operation.

[0008]

As described above, the actual shift operation is determined by the shift operation determination means based on the output shaft rotation speed of the belt type continuously variable transmission, not on the engine rotation speed. For example, the start time point and the end time point are accurately determined, and the vehicle state control by the vehicle state control means is executed at an appropriate timing.

Here, the vehicle state control based on the actual shift operation includes torque down control for temporarily reducing the output of the engine in the actual shift process, and gear ratio of the continuously variable transmission in the actual shift process. The control includes fixing control and control for releasing the lockup clutch in the actual shift process.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a skeleton view of an FF vehicle transverse transaxle to which a control device according to an embodiment of the present invention is applied, and FIG. 3 is a block diagram showing a configuration example of the control device. In FIG. 2, the power of the engine 10 includes a fluid coupling 12 with a lockup clutch, a forward / reverse switching device 14, and a belt type continuously variable transmission (hereinafter, referred to as CVT).
It is adapted to be transmitted to wheels 26 connected to a drive shaft 24 via 16, the auxiliary transmission 18, the reduction gear device 20, and the differential gear device 22.

The fluid coupling 12 is the engine 1
Pump impeller 30 connected to zero crankshaft 28
A turbine impeller 32 that is rotated by oil from the pump impeller 30; an output shaft 34 that is connected to the turbine impeller 32 such that it cannot rotate relative to the turbine impeller 32; and a damper 36 that is provided on the output shaft 34. A lock-up clutch 38 is provided. The pump impeller 30 includes a hydraulic pump 40.
Are connected to generate hydraulic pressure for operating the hydraulic actuators of the respective parts. In the fluid coupling 12, when the hydraulic oil is supplied to the disengagement side oil chamber 46 and the hydraulic oil in the engagement side oil chamber 48 is discharged, the lockup clutch 38 is released, and conversely, the engagement side oil chamber is released. When the hydraulic oil is supplied to the chamber 48 and the hydraulic oil in the release side oil chamber 46 is discharged, the lockup clutch 3
8 is engaged, and the crank shaft 28 and the output shaft 34 are directly connected.

The forward / reverse switching device 14 is a double pinion type planetary gear device which is selectively switched between a forward gear stage and a reverse gear stage in accordance with an operating position of a shift lever 142, which will be described later. It is arranged on the opposite side of the coupling 12. The output shaft 34 of the fluid coupling 12 extends through the shaft center of the input shaft 58 of the CVT 16 to the opposite side, and the planetary gear device has a sun gear 50 provided on the output shaft 34 so as not to rotate relative to the sun gear 50. 50, a pair of planet gears 54 and 56 that mesh with one and the other of the sun gear 50 and the ring gear 52 and mesh with each other, and rotatably support the planet gears 54 and 56. The CVT 16 also includes a carrier 60 that is connected to the input shaft 58 of the CVT 16 such that the carrier 60 cannot rotate relative to the input shaft 58. A multi-plate type forward clutch C1 is provided between the sun gear 50 and the carrier 60, and a multi-plate type reverse brake B1 is provided between the ring gear 52 and the housing 64. Engagement control is performed by the forward hydraulic actuator 42 and the reverse hydraulic actuator 44, respectively. When the forward clutch C1 is engaged in the state where the reverse brake B1 is released, the output shaft 34 and the carrier 60 are relatively non-rotatably connected and the input shaft 58 is rotated integrally with the output shaft 34 to move forward. When the clutch C1 is released and the reverse brake B1 is engaged, the rotation of the ring gear 52 is blocked and the carrier 6
Further, the input shaft 58 is decelerated and rotated in the direction opposite to the output shaft 34, that is, the direction in which the vehicle is moved backward.

The CVT 16 includes the input shaft 58 and an output shaft 70 parallel to the input shaft 58.
8. The output shaft 70 is provided with a drive-side variable pulley 72 and a driven-side variable pulley 74, and a transmission belt 76 is wound between the variable pulleys 72 and 74. The variable pulleys 72 and 74 have the input shaft 5
8 and the fixed rotating body 7 fixed to the output shaft 70, respectively.
8 and 80, and movable rotating bodies 82 and 84 provided on the input shaft 58 and the output shaft 70 so as to be movable in the axial direction and not to rotate relative to each other, respectively. By being moved in the axial direction by the hydraulic cylinders 86 and 88 arranged on the rear surface side, the V groove width, that is, the hanging diameter (effective diameter) of the transmission belt 76 is changed, and the gear ratio γ (= The rotation speed N _in of the input shaft 58 / the rotation speed N _out of the output shaft 70 is changed.

The sub transmission 18 is composed of a single pinion type planetary gear device, and is connected to the output shaft 70 so as to be relatively non-rotatable with a sun gear 90 which is rotatably arranged concentrically with the output shaft 70. A ring gear 92, a sun gear 90 and a planet gear 94 meshed with the ring gear 92, and a carrier 98 rotatably supporting the planet gear 94 and non-rotatably connected to the second output shaft 96. I have it. A multi-plate high speed stage clutch C2 is provided between the sun gear 90 and the carrier 98, and a one-way clutch 102 and a multi-plate low speed stage brake B2 are provided between the sun gear 90 and the housing 64. They are provided in series. Engagement control of the high speed gear clutch C2 and the low speed gear brake B2 is controlled by a high speed gear hydraulic actuator 106 and a low speed gear hydraulic actuator 108, respectively. In the low-speed gear stage established by the engagement of the low-speed stage brake B2, the one-way clutch 1
02 prevents rotation of the sun gear 90 in the opposite direction to the ring gear 92 in the positive torque drive state, but permits rotation in the same direction as the ring gear 92 in the negative torque drive (engine braking) state to allow the drive wheel 26 to rotate. The power transmission path for transmitting the rotational force to the engine 10 side is released. Accordingly, when the high speed gear clutch C2 is released and the low speed gear brake B2 is engaged, the low speed gear position is established. In this state, when the output shaft 70 of the CVT 16 is rotated in the direction of advancing the vehicle, the carrier 98 and the second output shaft 96 are decelerated in the same direction as the rotation direction of the output shaft 70. Conversely, the low-speed stage brake B2 is released and the high-speed stage clutch C2 is released.
When is engaged, the high speed gear is established. In this state, the sun gear 90 and the carrier 98 are coupled to each other such that they cannot rotate relative to each other, so that the planetary gear device can be integrally rotated, and the second output shaft 96 is rotated in the same direction as the output shaft 70. The gear can be switched by engaging the high speed clutch C2 while the low speed brake B2 is engaged during forward travel.

A first gear 110 is provided on the second output shaft 96, and a second gear 1 provided on the intermediate shaft 112.
It is meshed with 14. The intermediate shaft 112 is rotatably arranged around an axis c parallel to the axis b of the second output shaft 96, and also has a large-diameter gear 11 of the differential gear device 22.
The third gear 118 meshed with the gear No. 6 is provided. Second
The gear 114 has a larger diameter than the first gear 110, and
18 has a smaller diameter than the second gear 114,
The reduction gear device 20 is constituted by the gear 110, the second gear 114, and the third gear 118. The differential gear device 22 is rotatably supported around an axis orthogonal to the drive shaft 24, and a pair of differential small gears 120 that rotate integrally with the large diameter gear 116 and mesh with the differential small gears 120. A pair of differential gears 12 connected to a drive shaft 24
2 and. Therefore, the power transmitted from the reduction gear device 20 is evenly distributed to the left and right drive shafts 24 in the differential gear device 22, and then the left and right front wheels (drive wheels).
26 is transmitted.

In FIG. 3, a throttle sensor 130 provided in an intake pipe (not shown) of the engine 10 supplies a signal representing the throttle valve opening θ _th to the electronic control unit 132. Further, for example, the engine rotation sensor 134 provided in the igniter or the like is used to determine the rotation speed N of the engine 10.
A signal representing _e is provided to the electronic controller 132. Also,
The input shaft rotation sensor 136 and the output shaft rotation sensor 138 provided in the housing 64 are the input shaft 5 of the CVT 16.
Signals representing the rotation speed N _{in of} 8 and the rotation speed N _out of the output shaft 70 are supplied to the electronic control unit 132, respectively. Further, the vehicle speed sensor 140 provided in the housing 64 for detecting the rotation of the drive shaft 24, that is, the front wheel 26,
The rotation speed of the large-diameter gear 116 of the differential gear unit 22 is detected and a signal corresponding to the vehicle speed SPD is supplied to the electronic control unit 132. Further, the operation position sensor 144 is the shift lever 1
A signal representing the operating position P _{s of} 42 is supplied to the electronic control unit 132. The hydraulic control circuit 170 of FIG. 3 is configured as described in, for example, the specification of Japanese Patent Application No. 3-182980.

The electronic control unit 132 includes a CPU 146, R
A so-called microcomputer including an AM 148, a ROM 150, and an interface (not shown) is provided, and the CPU 146 uses the temporary storage function of the RAM 148 to process the input signal in accordance with a program stored in the ROM 150 in advance to change the gear ratio of the CVT 16. The first solenoid valve 152 and the second solenoid valve 154 are driven for control, and the third solenoid valve 156 and the fourth solenoid valve 158 are driven for engagement control of the lockup clutch 38 of the fluid coupling 12, The sixth solenoid valve 162 is driven to control the gear shift of the auxiliary transmission 18. Further, the torque down command signal ECT for performing the torque reduction control for alleviating the shift shock generated at the time of shifting the shift stage of the auxiliary transmission 18.
1 and ignition timing adjustment device 164 together with the retarded angle demand value ESA
Output to.

In the gear ratio control of the CVT 16 described above, for example, the target engine rotation speed, so that the engine 10 operates along an optimum curve that provides fuel economy and drivability,
The target input shaft rotation speed or the target gear ratio is determined, and the first solenoid valve 152 is set so that the target value and the actual value match.
And the second solenoid valve 154 is driven to adjust the gear ratio γ. Further, in the engagement control of the lockup clutch 38, for example, from the relationship stored in advance, it is determined whether or not it is the engagement region based on the vehicle speed SPD and the throttle valve opening θ _th, and it is determined that it is the engagement region. If the fourth solenoid valve 158 is turned off, the third solenoid valve 156 is turned on, and if it is determined that the release region is reached, the fourth solenoid valve 158 is turned off. The 3 solenoid valve 156 is also turned off. Further, in the tension control pressure control, for example, the tension control pressure P _{belt applied} to the secondary hydraulic cylinder 88 is stored in advance so as to obtain a target pressure that is a small value within a range in which the transmission belt 76 does not slip. Fifth from the relationship
The solenoid valve 160 is controlled. In the speed change control of the auxiliary transmission 18, as described in, for example, Japanese Patent Laid-Open No. 61-241561 or Japanese Patent Laid-Open No. 62-137239, for example, the actual relationship is stored from the prestored relationship shown in FIG. Throttle valve opening θ _th and gear ratio γ or vehicle speed SPD
The gear position to be switched is determined based on the above, and if the shift determination result is a high speed gear position, the sixth solenoid valve 162 is turned on, and if it is a low speed gear position, the sixth solenoid valve 162 is turned off. FIG. 5 shows the relationship between the operating speeds of the forward clutch C1, the reverse brake B1, the high speed clutch C2, and the low speed brake B2, which are controlled in relation to the operating position of the shift lever 142, and the shift speed. There is.

The vehicle state control routine, which is the main part of the operation of the electronic control unit 132, will be described below with reference to the flowchart of FIG. In the routine of FIG. 6, the auxiliary transmission 1
8 shift from low gear to high gear, ie L →
This is for alleviating the shift shock caused by the H shift.

[0021] In step S1 of FIG. 6, the signal supplied by the sensor, that is, the rotational speed N _e of the engine 10, the rotational speed N _in of the input shaft 58, the rotational speed N _out of the output shaft 70, the throttle valve opening θ _th , a signal corresponding to the vehicle speed SPD, and the operation position P _s of the shift lever 142 are read, and from these signals, the gear ratio γ of the CVT 16, the vehicle speed SPD, and the rotation speed N _out2 of the second output shaft 96.
Etc. are calculated. In step S2, the content of the flag F ₁ is whether or not "1" is determined. This flag F
₁ indicates that when the content is "1", the shift shock alleviation control for alleviating the shift shock generated due to the shift of the auxiliary transmission 18 has already been started.

If the determination in step S2 is affirmative, it means that the shift shock mitigation control has been started, and therefore, step S7 and subsequent steps, which will be described later, are executed. However, initially, the shift shock reduction control is not yet executed, and the determination in step S2 is denied. Therefore, in step S3, the shift determination of the auxiliary transmission 18 is performed in the gear shift control of the auxiliary transmission 18. Based on the drive signal of the sixth solenoid valve 162, for example, it is determined whether or not the shift output is performed based on. If the determination in step S3 is negative, it is not necessary to mitigate the shift shock of the auxiliary transmission 18, so this routine is ended.

If the determination in step S3 is affirmative, the shift determination of the auxiliary transmission 18 has been made, and therefore, in step S4, the determination reference value α and the determination reference value α used in steps S5 and S7 described later are set. β is determined based on the load of the engine 10, the vehicle speed SPD, and the like from a relational expression stored in advance. Further, in this step S4, the retarded angle request value ESA corresponding to the reduction amount of the output torque of the engine 10 is determined based on the load of the engine 10, the vehicle speed SPD, etc. from the relational expression stored in advance. Point B in FIG. 7 indicates this point. The judgment reference value α is a value for judging the start of the inertia phase, and the judgment reference value β is for judging just before the end of the inertia phase.
The judgment reference values α and β are determined so as to be necessary and sufficient values for accurately detecting the inertia phase. The inertia phase means a period during which the rotational speed of the input shaft (the output shaft 70 of the CVT 16) changes due to the shift operation of the auxiliary transmission 18, and a period during which the inertia torque occurs. During this period, the inertia torque of the member that changes the rotation speed from the crankshaft 28 to the output shaft 70 of the CVT 16 is generated.

Then, in step S5, the peak value N _out ^up which is the maximum point (inflection point) of the rotation speed N _out of the output shaft 70 read in each control cycle is determined by a well-known method, and the peak thereof is determined. Whether or not the actual rotation speed N _out has become lower than the value obtained by subtracting α from the value N _out ^up (N _out ^up −α), in other words, the peak value N _out ^up of the rotation speed N _out of the output shaft 70. It is determined whether or not the change width from (N _out ^up −N _out ) exceeds the determination reference value α. The step S5 is to determine the actual start of the gear shift operation by determining whether or not the rotation speed N _out of the output shaft 70 has changed due to the start of the engagement of the high speed gear clutch C2. ..

If the determination in step S5 is negative, this routine is ended. However, while the above steps are repeatedly executed, if the determination at step S5 is affirmative, then at step S6 the flag F
With ₁ of the contents is set to "1", a vehicle state control associated with L → H shift is executed. In the vehicle state control according to the present embodiment, the clutch release control for releasing the lock-up clutch 38 which has been in the engaged state to absorb the shift shock, and the engine output torque being temporarily reduced to perform the shift process. Engine output torque reduction control for reducing shift shock by reducing the peak torque is started. In this engine output torque reduction control, the torque down command signal ECT1 is issued and the already-determined retarded angle request value ESA is output to the ignition timing adjustment device 164. Therefore, the ignition timing of the engine 10 is changed to the ignition timing adjustment device 164. Is retarded by an angle corresponding to the retarded angle demand value ESA, and the output torque of the engine 10 is reduced by an amount corresponding to the retarded angle demand value ESA. Point C in FIG. 7 indicates this point.

After the content of the flag F ₁ is set to "1" as described above, it is judged in step S7 after step S2 of the following cycle whether the content of the flag F ₂ is "1". It The content of this flag F ₂ is “1”
When it is, it means that the gear shift is completed. Since the content is "0" at the beginning, step S8
Is executed. In this step S8, the rotational speed N _out after shifting to the high speed gear position is calculated from the previously stored gear ratio γ ^H after L → H shifting of the auxiliary transmission 18 and the actual rotational speed N _out2 of the second output shaft 96. ^H (= γ ^H · N _out2 ) is calculated, and the actual rotation speed N _out of the output shaft 70 is a value obtained by adding the judgment reference value β to the rotation speed N _out ^H after the shift (N _out ^H + β).
It is determined whether or not If the determination in step S8 is negative, this routine is ended.

While the above steps are repeatedly executed, the rotation speed N _out of the output shaft 70 is gradually decreased after the shift output is output, and the above step S8 is performed.
If the determination is affirmative, in step S9, the retard angle request value ESA is set so that the retard angle request value ESA approaches the original value.
By continuously changing the SA, the engine 1
The decrease amount of the output torque of 0 is gradually reduced. 7D
The dots indicate this point.

Next, in step S10, the output shaft 70
It is determined whether or not the actual rotation speed N _out of the above-mentioned rotation speed N _out matches the rotation speed N _out ^H after shifting to the high speed gear stage. If the determination in step S10 is negative, this routine is ended. However, the rotation speed N _out of the output shaft 70
Is further decreased and the determination in step S10 is affirmative, it means that the L → H shift of the auxiliary transmission 18 has been completed, and thus the retard angle request value ESA is updated to the original value in step S11. Moreover, the output of the torque reduction command signal ECT1 is stopped, and the content of the flag F ₂ is set to "1". Point E in FIG. 7 indicates this point.

Then, in the following step S12,
Elapsed time TE from shift output point B for establishing a high speed gear position of the auxiliary transmission 18 whether the host vehicle has reached the predetermined determination reference time T ₃ is determined. This judgment reference time T
₃ indicates the time elapsed from the shift output time point B at which the engagement of the lockup clutch 38 is permitted. But,
At the beginning of execution of step S11, the determination in step S12 is denied and the present routine is ended.

When the content of the flag F ₂ is set to "1" as described above, the determination in step S7 of the next cycle is affirmative, and therefore step S12 is executed thereafter. While the above steps are repeatedly executed, if the determination in step S12 is affirmative, step S1
In step 3, the engagement of the lockup clutch 38 is permitted, and in step S14, the contents of the flag F ₁ and flag F ₂ are reset to "0".
Point F in FIG. 7 indicates this point.

As described above, according to this embodiment, when the auxiliary transmission 18 shifts from L to H, the rotation speed N _out of the output shaft 70 changes from the inflection point in step S3 corresponding to the shift determining means. When the L → H shift output of the auxiliary transmission 18 is determined based on the width, and the actual shift operation start is determined in step S5 corresponding to the shift operation determination means, it corresponds to the vehicle state control means. In step S6, engine torque reduction control and lockup clutch disengagement control for alleviating a shift shock that occurs due to the L → H shift of the auxiliary transmission 18 are executed. Thus, in step S5, rather than the engine rotational speed N _e, CV
Since the start of the actual shift operation is determined based on the output shaft rotation speed N _{out of} T16, that is, the input shaft rotation speed of the auxiliary transmission 18, the actual start timing of the shift operation is accurately determined. Moreover, since the shift shock reducing control in step S6 is executed at an appropriate timing, a sufficient shift shock reducing action can be obtained.

Incidentally, the CVT 16 is, as shown in FIG.
Even thrust ratio of the hydraulic cylinder 86 and 88 is constant, since the gear ratio with the change in the transmitted torque has a property that changes from gamma _a to gamma _b, the change in the input shaft rotational speed N _in the subtransmission The torque temporarily changes due to inertia torque generated in connection with the gear change of the machine 18, and the change is delayed by a predetermined delay time τ as compared with the output shaft rotation speed N _out as shown in FIG. .. Therefore, the input shaft rotation speed N _in
In the conventional control device that uses the change of as the starting point of the actual shift operation, the time point of detecting the inertia phase becomes inaccurate,
The control for reducing the shift shock could not be executed at an appropriate timing.

Further, according to the present embodiment, the end point of the actual shift operation can be accurately determined, so that it is not necessary to provide a margin time as compared with the timer method of time control from the shift output point, for example. There is an advantage that the engine torque reduction control and the disengagement period of the lockup clutch 38 can be ended as soon as possible.

Next, also during the H → L shift of the auxiliary transmission 18, the same control as the operation shown in the flowchart of FIG. 6 may be performed. FIG. 10 is a time chart showing the operation obtained by this control. In step S5 in this case, the peak value N _out ^lp, which is the minimum point of the rotation speed N _out of the output shaft 70, is determined by a well-known method, and is stored in advance after the H → L shift of the auxiliary transmission 18. The gear ratio γ ^L and its peak value N _out ^lp (the rotational speed N of the second output shaft 96 at that time N
_out2 ) and the rotation speed N after shifting to the low gear
_out ^L (= γ ^L · N _out ^lp ) is calculated, and the actual value of the output shaft 70 is more than the value (N _out ^L −Δn) obtained by subtracting a predetermined determination reference value Δn from the rotation speed N _out ^L after the shift. It is determined whether or not the rotation speed N _out has increased. Further, in step S8, the actual rotation speed N _out of the output shaft 70 is set to the rotation speed N _out ^L after the shift by a predetermined determination reference value β ′.
It is determined whether or not the value obtained by subtracting (N _out ^L −β ′) is exceeded. Also in this embodiment, the actual start time point of the shift operation is accurately determined. The engine torque reduction control in the present embodiment is for suppressing torque vibration caused by twisting of the power transmission system that occurs in association with the H → L shift of the auxiliary transmission 18. Further, the judgment reference value Δn is determined in consideration of the deterioration of the engine torque reduction control.

Although one embodiment of the present invention has been described above with reference to the drawings, the present invention can be applied to other modes.

For example, in step S6 of the above-described embodiment, the disengagement control of the lockup clutch 38 and the main torque reduction control of the engine 10 are executed in order to mitigate the shift shock. Only may be performed.

Further, in step S6 of the above-described embodiment, in order to alleviate the shift shock, in addition to the release control of the lockup clutch 38 and the output torque reduction control of the engine 10, the change of the gear ratio γ of the CVT 16 is suppressed. Alternatively, a fixed control may be executed. The control for suppressing or fixing the change in the gear ratio γ of the CVT 16 is performed by the auxiliary transmission 1
This is to prevent a large amount of hydraulic oil from being consumed due to the change in the gear ratio γ of the CVT 16 during the L → H shift of No. 8 and the influence of the engagement operation and the engagement timing of the high speed gear clutch C2.

Further, the step S10 in the above-mentioned embodiment is
Alternatively, it may be determined whether or not the time elapsed since the determination in step S8 is affirmed exceeds a set value, or whether or not the output shaft rotation speed N _out matches k · N _W. It may be one that does. The same applies to step S10 of the embodiment shown in FIG. This N _W represents the rotation speed of the large diameter gear 116 detected by the vehicle speed sensor 140, and k is a coefficient for converting N _W into the output shaft rotation speed N _out .

The above description is merely one embodiment of the present invention, and the present invention can be modified in various ways without departing from the spirit of the invention.

[Brief description of drawings]

FIG. 1 is a diagram showing a main configuration of the present invention.

FIG. 2 is a skeleton diagram illustrating the configuration of a power transmission device for a vehicle to which an embodiment of the present invention is applied.

FIG. 3 is a block diagram showing a configuration of a control device used in the embodiment of FIG.

FIG. 4 is a diagram showing a relationship used for shift determination of the auxiliary transmission of FIG.

FIG. 5 is a diagram for explaining operating states of a gear stage of the auxiliary transmission and a solenoid valve for controlling the gear stage in the embodiments of FIGS. 2 and 3;

6 is a flowchart illustrating a main part of an operation of the electronic control device of FIG.

FIG. 7 is a time chart for explaining the control operation shown in FIG.

8 is a diagram showing a relationship between a thrust ratio of a pair of hydraulic cylinders and a gear ratio γ in relation to transmission torque in the CVT of FIG.

9 is an input shaft rotation speed N _in and an output shaft rotation speed N _out that are generated in association with the gear shift of the auxiliary transmission shown in FIG. 2;
It is a figure which shows the change characteristic of.

FIG. 10 is a diagram corresponding to FIG. 7 for explaining another embodiment of the present invention.

[Explanation of symbols]

16 belt type continuously variable transmission, 18 auxiliary transmission (continuously variable transmission) 86, 88 hydraulic cylinder 138 output shaft rotation speed sensor (output shaft rotation speed detection means) step S3 shift determination means step S5 shift operation determination means step S6 Vehicle state control means

Claims (1)

[Claims] 1. A belt type continuously variable transmission in which a gear ratio is continuously changed by a hydraulic cylinder, and an auxiliary transmission connected to a rear stage of the belt type continuously variable transmission and switched to a plurality of forward gear stages. A shift control device for a vehicle including a continuously variable transmission having: a shift determining means for determining a shift of the auxiliary transmission; and an output shaft rotation detecting an output shaft rotation speed of the belt type continuously variable transmission. Speed detection means, speed change operation determination means for determining an actual speed change operation based on a change width of the output shaft rotation speed detected by the output shaft rotation speed detection means from an inflection point; A vehicle state control means for controlling the vehicle state based on the actual shift operation when the actual shift operation is determined by the shift operation determination means after the shift of the auxiliary transmission is determined. Characterized by Shift control device for a vehicle with continuously variable transmission with the auxiliary transmission to.