JP2759938B2 - Vehicle transmission control method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a control method for a vehicle transmission.
You. Conventional technology A continuously variable transmission with a continuously variable transmission ratio
Both have two forward gears and are serially connected to the continuously variable transmission.
A vehicle transmission of a type including a connected auxiliary transmission is known.
ing. According to such a vehicle transmission, the speed of the continuously variable transmission is changed.
The feature is that the range can be made smaller and the continuously variable transmission becomes smaller.
And the auxiliary transmission is connected to the subsequent stage of the continuously variable transmission.
In this case, do not increase the input torque to the continuously variable transmission
However, there is a characteristic that a large driving force can be transmitted. For example,
It is described in Japanese Patent Application No. 58-144495 filed earlier by the present applicant.
That is what it is. Problems to be Solved by the Invention However, the gear change of the auxiliary transmission is determined in advance.
The vehicle speed and the throttle
Generally, it is automatically executed based on the opening of the
However, there is a gear change for vehicles according to the actual gear ratio of the continuously variable transmission.
Because the gear ratio of the entire machine changes, the auxiliary
The case does not become constant and the magnitude of the shift shock varies
Is inevitable, and in a continuously variable transmission,
Of inertia of rotating body such as variable pulley provided for
Is large, the inertia
Shift shock caused by the
Was sometimes impaired. In contrast, Japanese Patent Application No. 60-8179 filed earlier by the present applicant
As described in No. 2, the gear ratio of the continuously variable transmission is
Gear of the sub-transmission when the gear is in the
A control method that allows step change (shift)
Conceivable. According to this, the shift shock is effectively suppressed.
Can be controlled, but the speed ratio of the continuously variable transmission
Speed-up side than the gear ratio that allows
And the upshift
Speed-up side than the gear ratio that allows
Side and within the upshift permission area)
If you step on the accelerator and perform a kick-down operation,
During the shifting of the transmission, the continuously variable transmission stops
After a downshift due to a kickdown
Upshift permitted area when the speed ratio remains on the speed increasing side
Is upshifted, and this upshift
When the sub-transmission is set to the higher gear,
The gear ratio is still on the speed increasing side and goes down
Immediately after the upshift because it is within the shift permission area
Upshifts and so on are downshifted
And downshifting occur repeatedly. For this reason,
Upshift and downshift repeatedly
Inconvenient driving performance is impaired due to
Was. Means for Solving the Problems The present invention has been made in view of the above circumstances.
The point is that the gear ratio changes steplessly.
Transmission with at least two forward gears
And a sub-transmission connected in series with the continuously variable transmission
A method for controlling a dual-purpose transmission, comprising:
And a shift-up line separated to a higher vehicle speed than
The actual speed of the vehicle and the vehicle
Shift permission and front based on the actual required output of both
Shifts determined based on the actual transmission ratio of the continuously variable transmission
When the permission is obtained, the gear of the auxiliary transmission is switched off.
Be replaced. Function and Effect of the Invention In this way, the downshift line and the higher vehicle
A predetermined upshift line separated to the speed side
The actual speed of the vehicle and the actual speed of the vehicle
In addition to the shift permission determined based on the required output,
Shift permission determined based on the actual gear ratio of the step transmission
Is obtained, the gear stage of the auxiliary transmission is changed over.
Therefore, under optimal conditions according to the speed ratio of the continuously variable transmission,
The gear change of the transmission is performed, and the shift shock is favorable.
Relaxed appropriately. Also, even if the gear ratio of the continuously variable transmission
Speed-up side than the gear ratio that allows
And within the downshift permission area)
On the higher speed side than the gear ratio that permits shift
In the upshift permitted area)
The downshift was performed by the kick down operation
Even if the operation increases the required output and shifts
Since the vehicle state is located on the low vehicle speed side of the up line, the vehicle speed
Next shift-up until it goes high and crosses the shift-up line.
Can not be performed, downshifting during kick down operation
And upshifting and driving
Inhibition of the property is suitably prevented. Hereinafter, an application example of the present invention will be described in detail with reference to the drawings.
I do. In FIG. 2, the power of the engine (not shown) is
Hand 10, belt-type continuously variable transmission (hereinafter referred to as CVT) 12, sub-variable
Drive shaft, intermediate gear device 16, and differential operation 18 to drive shaft
20 to drive wheels (not shown) connected to
ing. The fluid coupling 10 is connected to the crankshaft 22 of the engine.
Pump 24 fixed to the input shaft 26 of the CVT 12 and the pump 24
Turbine 28 rotated by oil from the
Lock-up clutch fixed to the input shaft 26 through the
And 32. Lock-up clutch 32
For example, vehicle speed or engine speed or turbine 28
Activated when the rotation speed exceeds a predetermined value,
The link shaft 22 and the input shaft 26 are directly connected. The CVT 12 is provided on the input shaft 26 and the output shaft 34, respectively.
Variable pulleys 36 and 38
And a conduction belt 40 wound around the transmission belt 38. Yes
The variable pulleys 36 and 38 are attached to the input shaft 26 and the output shaft 34.
The fixed rotating bodies 42 and 44, which are fixed respectively, and the input shaft 26 and
And the output shaft 34 are movable in the axial direction and
It is composed of movable rotating bodies 46 and 48
The movable rotating bodies 46 and 48 are attached to the hydraulic cylinders 50 and 52.
Therefore, by being moved, the V groove width,
The hanging diameter (effective diameter) of the default 40 has been changed, and the speed of the CVT12 has been changed.
Ratio γ (= rotation speed N of input shaft 26) _in / Rotation speed N of output shaft 34
_out ) Is changed. Hydraulic cylinder 50
Is operated exclusively to change the gear ratio γ and the hydraulic
Linda 52 is used only within the range where slippage of conduction belt 40 does not occur.
It is operated so that a minimum clamping force is obtained. In addition,
The oil pump 54 constitutes a hydraulic source of a hydraulic control device described later.
Connecting shaft (not shown) vertically passing through the input shaft 26
Connected to the crankshaft 22 by the engine
It is driven to rotate. The auxiliary transmission 14 is connected in series after the CVT 12 and
High and low gears according to both driving conditions
Is a stepped transmission that automatically switches to the CVT12
Of the Ravigneaux type
Includes a planetary gear set. This planetary gear set
A pair of first sun gear 56 and second sun gear 58;
A first planetary gear 60 meshing with the gear 56, and the first planetary gear
A second planetary gear 62 meshing with the second sun gear 58;
A ring gear 64 meshing with the first planetary gear 60;
A carrier that rotatably supports the second planetary gear 62 and the second planetary gear 62.
A 66 is provided. The second sun gear 58 is connected to the output shaft 34.
It is fixed to the shaft 68 that is integrally connected, and the carrier 66 is output
It is fixed to the gear 70. The high speed clutch 72 is
By controlling the engagement with the first sun gear 56, the low speed
Key 74 controls the engagement of the first sun gear 56 with the housing
The reverse brake 76 engages the housing of the ring gear 64.
To control the engagement. FIG. 3 shows each friction engagement of the auxiliary transmission 14.
Show the operating state of the elements and the reduction ratio in each range
I have. In the figure, ○ indicates the engaged state, and × indicates the released state.
Where ρ1 and ρ2 are gear ratios defined by the following equations.
You. ρ1 = Z _s1 / Z _r ρ2 = Z _s2 / Z _r Where Z _s1 Is the number of teeth of the first sun gear 56, Z _s2 Is the second sangi
A 58 teeth, Z _r Is the number of teeth of the ring gear 64. Therefore, the low gear stages in the L, S, and D ranges
Then, the low-speed gear brake 74 as the first friction engagement device is
Actuated to fix the first sun gear 56, so deceleration
Power is transmitted at the ratio (1 + ρ1 / ρ2), but L, S, and
The second frictional engagement device
Planetary gear set by the operation of the high-speed stage clutch 72
The whole unit rotates as a unit, thereby moving at a reduction ratio of 1.
Power is transmitted. In the R range, the reverse brake 76
The ring gear 64 is fixed to the housing by the operation of
Therefore, the power is transmitted by the reverse rotation of the gear ratio (1-1 / ρ2).
You. The output gear 70 of the auxiliary transmission 14 is operated via the intermediate gear device 16.
The power of the engine is connected to the
After being distributed to the left and right drive shafts 20 at 18, respectively,
It is transmitted to the right drive wheel. FIG. 4 is a diagram for controlling the vehicle power transmission device shown in FIG.
Fig. 2 shows a hydraulic control circuit for the present invention. Oil pump 54 is shown
Do not strain the hydraulic oil etc. returned into the oil tank
It is pumped through 80 to suction line pressure oil passage 82. Slot
The torque valve 84 is a slot corresponding to the throttle valve opening θ.
Pressure P _th At its output port 86. Throttle bar
The spool 88 of the lube 84 rotates with the throttle valve
As the throttle valve opening θ increases from the throttle cam 90,
Acting force and feedback pressure from control port 92
Throttle pressure P as _th And in the opposite direction, the line
The opening and closing of the pressure oil passage 82 and the output port 86 are controlled. Manua
The valve 94 is connected to the shift levers L (low) and S (second
D), D (drive), N (neutral), R (river)
), And P (parking) range
It is positioned in the line direction and is
The second line pressure Pl2 output from the output port 258 of the fourth line
In the R range, the reverse brake 76
To the hydraulic actuator 76 'to operate the
To port 98, to ports 98 and 100 for D range
Lead each. The relief valve 102 is connected to the first
When the line pressure Pl1 exceeds a predetermined value, the oil in the line
It has a function as a safety valve to let the valve escape. The secondary hydraulic passage 104 is connected to the orifice 106 and the primary
Port 110 for discharging excess oil from the
Connected to the line pressure oil passage 82 via
The hydraulic valve 112 is connected to the secondary hydraulic oil via the orifice 114.
A control room 116 connected to the road 104,
In connection with the hydraulic pressure and the load of the spring 118, the secondary hydraulic
Control the connection to the secondary hydraulic oil passage 104
Maintain Pz at a predetermined value. Lube oil passage 122 is connected to port 120 and
And is connected to the secondary hydraulic passage 104 through the orifice 124
I have. The lock-up control valve 126 flows through the secondary hydraulic oil passage 104.
The engagement side and disengagement of the lock-up clutch 32 in the joint 10
Selectively connect to the release side. Lock-up solenoid valve 128
Is the control chamber 130 and the drain 132 of the lock-up control valve 126.
The solenoid valve 128 is off (de-energized state)
If it is the secondary oil to the release side of the lock-up clutch 32
The secondary hydraulic pressure Pz is transmitted from the pressure oil passage 104 to
It is transmitted via the fluid in the hand 10. However, the solenoid valve 128
Lock-up clutch when is on (excited)
To the engagement side of 32 and to the oil cooler 134
The secondary hydraulic pressure Pz is supplied and power is locked up.
It is transmitted through the switch 32. Cooler bypass valve 136
Control the pressure. The gear ratio control valve device includes a first spool valve 142 and a first spool valve 142.
A shift direction switching valve device 138 comprising an electromagnetic valve 144;
Speed changeover device comprising a throttle valve 146 and a second solenoid valve 148
Device 140 is provided. During the period when the first solenoid valve 144 is off
The spool of the first spool valve 142 is controlled by the secondary hydraulic pressure Pz of the chamber 150.
Resilient spring 152 and the first line of port 154
Pressure Pl1 is supplied to the second spool port 156 via the port 156 of the first spool valve 142.
It is sent to port 158 of spool valve 146 and
The connection with the Inn 162 has been broken. As a result, the gear ratio γ
Is switched in the decreasing direction. When the first solenoid valve 144 is on
During a certain period, the oil pressure in the chamber 150 is changed to the drain 164 of the first solenoid valve 144.
And the spool of the first spool valve 142
Pressed toward chamber 150 by spring 152, line 156
No pressure Pl1 occurs, and port 160 is connected to drain 162.
You. As a result, the gear ratio is switched in the increasing direction. While the second solenoid valve 148 is off, the second spool valve 146
Is pushed toward the spring 168 by the secondary hydraulic pressure Pz in the chamber 166.
Port 158 and port 170 are disconnected,
Port 172 is connected to port 174. Ports 170 and 172 are C
It is connected to the input side hydraulic cylinder 50 of VT12. 2nd
While the magnetic valve 148 is on, the oil pressure in the chamber
8 is discharged from the drain 176 of the second spool valve 146,
The pool is pressed by spring 168 towards chamber 166 and port 15
8 is connected to port 170 and the connection between port 172 and port 174.
The connection is cut off. Port 174 is connected to port 160 via oil passage 180
Connected to Orifice 182 is the second solenoid valve 148
A small amount of oil is introduced from port 158 to port 170 at the time of the start.
Therefore, the first solenoid valve 144 is off and the second solenoid valve 148
While the is on, turn off the input side hydraulic cylinder 50 of CVT12.
Is supplied quickly, and the gear ratio γ decreases rapidly.
You. When the first solenoid valve 144 is off and the second solenoid valve 148 is off
During a certain period, oil is supplied to the input side hydraulic cylinder 50 of the CVT12.
The supply is performed through the orifice 182 and the gear ratio γ of the CVT 12
Gradually becomes smaller. When the first solenoid valve 144 is on and the
2 When the solenoid valve 148 is ON, the input side hydraulic
Oil is not supplied or discharged to the
The speed ratio γ gradually decreases according to leakage from the hydraulic cylinder 50, etc.
To increase. The first solenoid valve 144 is on and the second solenoid valve 148 is
During the off period, the oil in the input side hydraulic cylinder 50 is drained.
The gear ratio γ of CVT12 is rapidly
To increase. The speed ratio detection valve 184 is in sliding contact with the movable rotator 46 on the input side.
Rod 194, and the rod 194 is the axis of the movable rotating body 46.
Move in the axial direction by a displacement equal to the displacement in the linear direction
Can be The gear ratio detection valve 184 has a fixed rotation on the input side of CVT12.
As the displacement of the movable rotating body 46 with respect to the body 42 increases,
The discharge flow rate of the oil supplied through the orifice 218
The speed ratio pressure Pr at the output port 216 is
It decreases with increasing γ. Gear ratio pressure Pr is output port 21
6 by controlling the discharge of hydraulic medium supplied to
Generated. The cut-off valve 262 controls the lock-up control valve 126.
The chamber 230 communicating with the control chamber 130 via the oil passage 228, and
Relative to the oil pressure in the chamber 230 and the spring force of the spring 232.
Spool 234 and the solenoid valve 128 is off,
That is, when the lockup clutch 32 is in the released state.
(When shifting gears in the auxiliary transmission 14, when the power transmission system
Lock-up clutch 32 released to absorb shots
Is closed) and the gear ratio pressure Pr is
The transmission to the regulator valve 108 is prevented. Primary regulation as first line pressure generating means
Data valve 108 is throttle pressure P _th Port to which is supplied
236, port 238 to which gear ratio pressure Pr is supplied, line pressure oil passage 8
Port 240 connected to 2, suction side of oil pump 54
Through port 242 and orifice 244
Port 246, which is supplied with the first line pressure Pl1,
Moves linearly to control connection between port 240 and port 242
Spool 248, throttle pressure P _th Receiving spool 248
250, which biases the
The spring 252 biases the 248 toward the support 238.
You. Remove the pressure receiving areas of the two lands from under the spool 248.
A1, A2 respectively, throttle pressure P _th 250 spools
A3 is the land pressure receiving area, and W1 is the acting force of the spring 252.
Then, equations (1) and (2) hold. The cutoff valve 226 opens and the gear ratio pressure Pr
Is coming, Pl1 = (A3 · P _th + W1-A1 · Pr) / (A2-A1)… (1) The cut-off valve 226 closes and the gear ratio pressure Pr is applied to the port 238.
If not, Pl1 = (A3 · P _th + W1) / (A2-A1) (2) Sub-primary valve as second line pressure generating means
Block 254 is connected to an input port 256, to which the first line pressure Pl1 is led.
The output port 258 at which the second line pressure Pl2 is generated, and the gear ratio P
r port 260, the second as feedback pressure
Of the line pressure Pl2 through the orifice 262
264, control opening and closing of input port 256 and output port 258
Spool 266, throttle pressure P _th Port 268,
Throttle pressure P from port 268 _th Receiving spool 26
Spool 270 biasing 6 toward port 260, and
A spring 272 that urges the valve 266 toward the port 260.
You. The pressure receiving area of the two lands from the bottom of the spool 266 is B1,
B2, throttle pressure P _th Receiving spool 270 land
The compression area is defined as B3, and the elastic force of the spring 272 is defined as W2.
In other words, the second line pressure Pl2 is obtained according to the following equation (3).
Is forced. Pl2 = (B3 · P _th + W2−B1 · Pr) / (B2−B1) (3) The shift valve 274 is a clutch for the high speed stage of the subtransmission 14.
Switch 72 and the hydraulic
Selectively apply hydraulic pressure in the tutors 72 'and 74'
The shift lever D, S, L range when the second
Input port 276 and output port 27 through which the line pressure Pl2 is led
8,280 with orifice 282 and ending at drain 284
Port 288 connected to the drain oil passage 286
When the manual valve 94 is
Control port 300 to which pressure Pl2 is supplied, and other control ports.
302, 304, drain 306, spool 308, and its
Has a spring 310 that biases the pool 308 toward the control port 304
doing. Control ports 302 and 304 are connected through orifices 312.
The secondary hydraulic pressure Pz is guided by the
It is controlled by a solenoid valve 314 for the shaft. Under spool 308
The pressure receiving areas of the two lands are S1 and S2, respectively.
1 <S2. The solenoid valve 314 is turned on and off when the vehicle is running.
It is controlled in relation to the transfer parameters. When the spool 308 is located at the spring 310 side, the input port
Port 276 is connected to output port 278, and output port 280 is
Port 288. Therefore, from output port 278
Accumulator with second line pressure Pl2 having piston 318
To the actuator 320 and the hydraulic actuator 72 'for the high-speed stage
And the inside of the hydraulic actuator 74 'for low speed
As a result, the auxiliary transmission 14 is brought into a high gear. If the spool 308 is at the position on the control port 304 side,
Output port 276 is connected to output port 280 and output port 27
8 is connected to the drain 306. Therefore, the output port
The second line pressure Pl2 from 280 is
Hydraulic activator supplied to eta 74 'and for high speed
The pressure in the heater 72 'is exhausted, and the sub-transmission 14
Becomes For the L and S ranges, the second line pressure
Since Pl2 is not guided, when the solenoid valve 314 is turned off,
The spool 308 initially acts on the land having the pressure receiving area S2.
The next hydraulic pressure Pz then acts on the land of the pressure receiving area S1.
The secondary hydraulic pressure Pz moves to the spring 310 side, but the solenoid valve 3
When 14 turns on, the hydraulic pressure at control ports 302 and 304 decreases.
Therefore, the spool 308 is controlled according to the biasing force of the spring 310.
Move to the port 304 side. Therefore, in the L and S ranges,
In response to the off and on states of the valve 314, the auxiliary transmission 14
Is switched to the high gear and the low gear.
You. In the D range, the second line pressure Pl2 is introduced to the control port 300.
The spool 308 is once in the position of the spring 310 side
And the second from the control port 300 to the land of the pressure receiving area S2
The line pressure Pl2 acts, and the solenoid valve 314 is turned on and off thereafter.
The spool 308 is held in the position on the spring 310 side
You. Therefore, the auxiliary transmission 14 is held at the high gear. The shift timing valve 324 is a hydraulic
A control port 326 communicating with the tutor 72 ', and
The axial position is controlled by the hydraulic pressure at control port 326.
Has a spool 328 for shifting from a low gear to a high gear.
Hydraulic actuator 72 'for high speed gear during upshift
Hydraulic Actuator for Oil Supply Flow and Low Speed
The amount of oil discharged from the motor 74 'is controlled. FIG. 5 shows an electronic device for controlling the operation of the above-mentioned hydraulic control device.
The circuit is shown. So-called microphone consisting of CPU, RAM, ROM, etc.
The electronic control unit 330 equipped with a computer
Linked to accelerator pedal (not shown)
Throttle valve opening θ of throttle valve, output shaft 34 of CVT12
Rotation speed N _out (Rotation speed of the input-side rotary shaft of the auxiliary transmission 14
n _in ), Rotation speed N of input shaft 26 of CVT12 _in Engine cooling water
Temperature T _W , Shift lever operating position P _S Signals representing
Is supplied. The CPU in the electronic control unit 330 temporarily stores the RAM.
Using a program stored in ROM in advance while using the memory function
Therefore, the input signal is processed, and the solenoid valves 128, 144, 148, 314 are processed.
The signals for driving the
Output. In the electronic control unit 330, a main
The electronic control unit is initialized by executing
And input signals from each sensor are read
On the other hand, based on the read signal,
Calculated and according to the input signal conditions, the engine and CVT1
A die for diagnosing whether the 2nd class is operating normally
Agnosis, engine ignition timing, fuel injection amount, etc.
Control interaction with engine computer to control
Control between running engine computers, vehicle speed V and
Relationship determined in advance based on the throttle valve opening θ
Control the solenoid valve 128 that activates the lock-up clutch 32
Control, vehicle speed V, throttle valve
Based on the opening θ and the change ratio, the gear stage of the
Gear shifting system that automatically switches to one of the low gear stages
The gear ratio control of the CVT12 is sequentially or selectively repeated.
Returned and executed. Hereinafter, in order to automatically change the gear position of the subtransmission 14,
Shift control operation will be described with reference to the flowchart of FIG.
I do. FIG. 1 shows a shift control for switching and controlling the gear stage of the auxiliary transmission 14.
This is the main part of the control routine. First, step S1 is executed.
As a result, the current gear of the subtransmission
The shift solenoid valve 314 determines whether the gear is a gear or a low gear.
Is determined on the basis of the drive signal and the like supplied to the controller. S
If it is determined in step S1 that the gear is a high-speed gear,
Switches from a high gear to a high gear (shift down
Step 2 and the following steps are performed to control (i). In step S2, the throttle valve opening θ, the output shaft
34 rotation speed N _out , And the rotation speed N of the input shaft 26 _in Read
And the rotation speed N of the output shaft 34 _out , Sub transmission 14
Current gear ratio, differential gear ratio, drive wheel radius
The vehicle speed v is calculated based on the rotation speed of the output shaft 34.
Degree N _out And the rotation speed N of the input shaft 26 _in Based on the actual
The gear ratio γ is calculated. Then, follow the steps S3 and
In step S4, downshift permission based on the shift diagram is
Yes, and downshift permission based on gear ratio
Is determined. First, in step S3, for example, as shown in FIG.
The shift down line in the shift diagram previously stored in the ROM
Based on the actual vehicle speed v and the throttle valve opening θ
Downshift is determined. That is, the actual vehicle speed v and
Point indicating the throttle valve opening θ
It is determined when you cross the downshift line.
Next, in step S4, the gear ratio γ of the CVT 12 is determined in advance.
Value γ ₀ It is determined whether it is less than or ratio. Sand
That is, in step S4, the actual gear ratio γ is determined as shown in FIG.
Whether it is within the shift down permission area indicated by the shaded area
It is for refusing. Note that the above value γ ₀ Is a constant
May be a function of the throttle valve opening θ.
Is determined based on the actual throttle valve opening θ
May be. At least one of step S3 and step S4
If downshift permission is not determined in
Step S5 is executed to maintain the high gear of the subtransmission 14.
However, the shift is performed in both Step S3 and Step S4.
If downdown permission is determined, execution of step S6
The gear is switched from the high gear to the low gear. That is,
The solenoid valve 314, which was in the non-excited state
Switches the high-speed gear of the auxiliary transmission 14 to the low-speed gear
And the lock-up clutch 32 is engaged.
The solenoid valve 128 does not excite for a certain period
The lock-up clutch 32 is primary by being magnetized.
Will be released. In the step S1, the current gear of the subtransmission 14 is
If it is determined that the gear is a low gear,
To shift to a higher gear (upshift)
Step S7 and the subsequent steps are executed. In step S7, the vehicle speed is set in the same manner as in step S2.
V, throttle valve opening θ and gear ratio γ are detected respectively.
You. Then, in step S8 and step S9,
Shift up permission based on the shift diagram, and
The following shift up permission is determined. First,
In step S8, for example, the data stored in the ROM shown in FIG.
From the shift-up line in the shift diagram
Upshift is determined based on the throttle valve opening θ.
You. That is, the actual vehicle speed v and the throttle valve opening θ
Point crosses the upshift line in the direction of increasing vehicle speed
It will be judged when it comes. Then, in step S9
Is the gear ratio γ of the CVT 12 is a predetermined value γ ₁ Less than
It is determined whether or not it is. That is, in step S9
It is determined that the actual gear ratio γ is the shift ratio indicated by the oblique lines in FIG.
To determine whether or not it is within the
You. Note that the above value γ ₁ Can be a constant value, but even if
Is the function of the throttle valve opening θ and the actual slot
May be determined based on the valve opening degree θ. At least one of step S8 and step S9 above
If shift up permission is not determined in
Step S10 is executed to maintain the low gear of the subtransmission 14.
However, in both step S8 and step S9,
When the downshift permission is determined, execution of step S11 is performed.
The lower gear is switched to the higher gear. Sand
The solenoid valve 314, which was in the excited state, is now in the non-excited state.
And the lower gear of the auxiliary transmission 14 is shifted to the higher gear.
The gears can be switched to gears and the lock-up clutch 32
Is in the engaged state, the solenoid valve 128 is
Lock-up clutch by being de-energized for a fixed period
32 is temporarily released. In this embodiment, the above steps are repeated.
Be executed by the shift down line and higher
A predetermined line consisting of an upshift line separated to the vehicle speed side
The actual speed of the vehicle and the actual
Gear change, which is determined based on the required output when
Shift permission determined based on the actual speed ratio γ of the speed change device 12.
The gear stage of the auxiliary transmission 14 is switched when
The optimal condition according to the speed ratio γ of the continuously variable transmission 12.
The gear stage of the auxiliary transmission 14 is switched under the
The shock is suitably reduced. Also, even if the continuously variable transmission 12
Is the gear ratio γ that allows downshifting ₀ than
Speed-up side (downshift is permitted on the side where the gear ratio becomes smaller)
Gear ratio γ within the range) and allowing upshifting ₁ Than
Also on the speed increasing side (the side where the gear ratio becomes smaller and
Area), the kick-down operation
Even if a shift is performed, a request is issued by that operation.
As the power increases, the vehicle condition is shifted to the lower vehicle speed side of the upshift line.
Because it is located, the vehicle speed increases and it exceeds the upshift line
The next shift up cannot be performed until
Repeat the downshift and upshift during
And prevent drivability from being impaired due to it
Is done. That is, the determination of the gear change of the subtransmission 14 is determined by the CV
T12 gear ratio γ (constant value or throttle valve opening θ
Number), the value of the gear ratio γ is
Upshift permitted area and high speed at 14 low gears
When the gear is in the downshift permission area
is there. In such a case, for example, shifting to the point A in FIG.
Kick down operation with accelerator pedal when ratio γ is present
Is performed, the CV
The gear ratio γ of T12 is still shifting as shown at point B in FIG.
In the up-permission area and the gear is immediately shifted up.
U. Immediately after this upshift, the gear ratio γ is shifted.
The gear is shifted down immediately because it is within the
Would. Conventionally, such an alternate gear shift is performed.
Hunting occurred and the drivability was impaired
It is. However, in the present embodiment, the gear speed of the subtransmission
As a condition for the switching, for example, as shown in FIG.
Shift permission judgment based on the shift
Immediately after going down, the vehicle speed v reaches the upshift line.
Therefore, the hunting does not occur. Further, in the present embodiment, the gear stage of the subtransmission 14 is switched.
The value of the gear ratio γ of the CVT 12 ₀ Or γ ₁ less than
Because of the restriction, shift shock is appropriately suppressed.
It is. Those γ ₀ Or γ ₁ Values are for all vehicle transmissions
The gear ratio of the body is set to a value that does not easily cause shift shock.
Is being used. As described above, one application example of the present invention has been described.
Applies to other embodiments. For example, instead of the actual throttle valve opening θ,
The amount representing the required output such as the cell pedal operation amount and the intake pipe negative pressure
May be used. In the above-described embodiment, the sub-transmission 14 is continuously variable.
Directly connected to machine 12, but not necessarily limited to this.
Not. The above is merely an example of the present invention.
Therefore, the present invention may be variously modified without departing from the spirit thereof.
Further modifications can be made.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flowchart for explaining the main part of the operation of the apparatus to which the present invention is applied. FIG. 2 is a skeleton view showing a vehicle power transmission device to which the present invention is applied. FIG. 3 shows the second
FIG. 4 is a diagram illustrating a relationship between a range of a subtransmission and a friction engagement device in the illustrated device. FIG. 4 is a circuit diagram showing in detail a hydraulic control device for operating the device of FIG. Fifth
FIG. 3 is a block diagram showing an electric control circuit provided in the apparatus shown in FIG. FIGS. 6, 7, and 8 show the first embodiment.
It is a figure which shows the shift determination reference value of the subtransmission used by the flowchart of a figure, respectively. 12: continuously variable transmission 14: auxiliary transmission

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Claims (1)

(57) [Claims] Control method for a vehicle transmission including a continuously variable transmission in which a gear ratio is steplessly changed, and a subtransmission having at least two forward gears and connected in series with the continuously variable transmission Wherein a determination is made based on the actual speed of the vehicle and the actual required output of the vehicle from a predetermined shift diagram including a shift-down line and a shift-up line separated to a higher vehicle speed side than the shift-down line. The gear stage of the auxiliary transmission is switched when both a shift permission and a shift permission determined based on an actual gear ratio of the continuously variable transmission are obtained. Control method.