JPS61132434A - Gear ratio control device in stepless speed change unit - Google Patents

Abstract

PURPOSE:To make it possible to restrain variations in drive force transmitted from an engine to wheels, by changing the gear ratio of a stepless speed change unit with the use of a gear ratio regulating means when the load of the engine varies. CONSTITUTION:In a stepless speed change unit 9 in which the gear ratio is changed by adjusting the groove gaps of drive and driven pulleys by means of hydraulic actuators, there is provided a gear ratio regulating means a for changing the gear ratio. Further there is provided a load variation detecting means (accessory operation detecting sensors, etc.) for detecting variations in load of an engine, such as, for example, variations in load which is effected when the accesories including an air-conditioning system are changed over from their inoperative condition to their operative condition or vice versa. Further, upon detection of variations in load, a gear ratio control means C delivers a control signal for decreasing the change rate of gear ratio of the stepless speed change unit 9 to a regulating means d for restraining variations in drive force transmitted to the engine to the wheels.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a gear ratio control device that controls a gear ratio in a continuously variable transmission mechanism provided in a power transmission path from an engine to drive wheels.

(Prior art) In vehicles, in order to efficiently transmit the output of the engine to the wheels, which are driven objects, a transmission mechanism is disposed between the engine and the wheels, and the output of the engine is transmitted to the wheels via the transmission mechanism. As this transmission mechanism, one that employs a continuously variable transmission mechanism that can continuously change the transmission ratio within a predetermined range is known. A continuously variable transmission mechanism installed in such a vehicle is disclosed in, for example, Japanese Patent Application Laid-Open No. 55-767.
As described in Japanese Patent No. 09, the gear ratio is controlled based on the vehicle speed or engine rotational speed and the throttle valve opening adjusted by operating an accelerator adjustment means such as an accelerator pedal.

In such a case, the gear ratio of the continuously variable transmission mechanism is usually controlled such that the engine speed, and therefore the manual rotation speed of the continuously variable transmission mechanism, is uniquely determined by the throttle valve opening. . That is, the gear ratio is controlled so that a constant engine speed is obtained for each throttle valve opening value, and therefore a constant engine output is obtained.

For example, the relationship between the accelerator opening α corresponding to the throttle valve opening and the input shaft rotation speed Np of the continuously variable transmission mechanism is
Control is performed so as to follow the speed change characteristics represented by the speed change diagram as shown in FIG. In the shift diagram of FIG. 10, the area labeled "down" is the shift area, and the area labeled "1" ρ° is the shift amplifier area. Such control is
The electronic control means for the continuously variable transmission mechanism is supplied with detection signals from the flo-sotorhalb opening detection means or the accelerator opening detection means and the input rotation speed detection means of the continuously variable transmission mechanism, and the electronic control means responds to each detection signal. The control output is sent to the gear ratio adjustment section of the continuously variable transmission mechanism.

By the way, when the speed ratio control is performed based on such speed change characteristics, for example, when the vehicle is running at a constant speed with a constant accelerator opening, the motor operates by receiving the driving force from the engine. , when auxiliary equipment such as an air conditioner installed in the vehicle is switched from an inactive state to an active state, or from an active state to a non-active state, or when the vehicle enters a downhill or uphill slope, etc. When a load fluctuation occurs for the engine, the continuously variable transmission mechanism performs rapid upshifts or shifts according to predetermined speed change characteristics as shown in Figure 10 in order to maintain the input shaft rotation speed. It will be controlled to go down. As a result, fluctuations in the driving force transmitted from the engine to the wheels of the vehicle occur, resulting in an undesirable drop or rise in vehicle speed, and the driver must use the accelerator pedal etc. to correct this. This results in the inconvenience of having to operate the accelerator adjustment means.

(Objective of the Invention) In view of the above, the present invention is designed to control the gear ratio of a continuously variable transmission mechanism provided in a power transmission path from the engine of a vehicle to the wheels according to predetermined gear change characteristics, for example. ,
If the load on the engine changes while the vehicle is running with a constant accelerator opening, the resulting fluctuations in the driving force transmitted from the engine to the wheels can be suppressed, making driving easier. To provide a gear ratio control device for a continuously variable transmission that does not force a user to frequently perform troublesome accelerator operations.

(Structure of the Invention) The gear ratio control device for a continuously variable transmission according to the present invention, as shown in the basic structure in FIG. transmission ratio adjustment means for changing the transmission ratio of the engine; load fluctuation detection means for detecting load fluctuations on the engine; and transmission from the engine to the wheels when a load fluctuation occurs on the engine based on the detection output from the load fluctuation detection means. In order to suppress fluctuations in the driving force caused by the transmission, the gear ratio control means sends a control signal to the gear ratio adjustment means to change the gear ratio of the continuously variable transmission mechanism.

With this configuration, when a load fluctuation occurs on the engine, a control signal sent from the gear ratio control means to the gear ratio adjustment means can be used to control, for example, the speed ratio change speed of the continuously variable transmission mechanism or the speed change. The shift characteristics represented by the diagram are changed, and fluctuations in the driving force transmitted from the engine to the wheels are suppressed.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows an outline of a drive control section of a vehicle to which an example of the gear ratio control device for a continuously variable transmission according to the present invention is applied. In FIG. 2, the intake passage 2 of the engine 1 has a 9
A throttle valve 3 is provided to change the load.

This throttle valve 3 is a throttle actuator 4
The open/close position is driven to open and close by the fluorochrome position sensor 5. Note that the bundle portion of the intake passage 2 on the downstream side of the throttle valve 3 forms branch passages 2a, 2b, 2c, and 2d that communicate with each cylinder, and these branch passages 2a.

Fuel injection valves (not shown) are provided at 2b, 2c, and 2d.

The output shaft 6 of the engine 1 is connected to a continuously variable transmission m9 via a clutch 7 and a switching gear train 8, and the output shaft 10 of this continuously variable transmission 9 is connected to drive wheels 12 via a differential gear 11. .

Also, an engine rotation speed detection sensor 13 that detects the rotation speed of the output shaft 6 of the engine 1. A clutch output shaft rotation speed detection sensor 15 for detecting the rotation speed of the output shaft 14 of the clutch 7.
Transmission input shaft rotation speed detection sensor 17 for detecting the rotation speed of the input shaft 16 of the continuously variable transmission a9. Further, transmission output shaft rotation speed detection sensors 18 for detecting the rotation speed of the output shaft 10 of the continuously variable transmission 9, and therefore the vehicle speed, are installed at predetermined positions. Then, the aforementioned throttle position sensor 5
Throttle position signal P5. The engine rotation speed signal P2 from the engine rotation speed detection sensor 13 mentioned above.
Clutch output shaft rotation speed signal P4 from clutch output shaft rotation speed detection sensor 15, transmission input shaft rotation speed signal P6 from transmission input shaft rotation speed detection sensor 17, gear shift from transmission output shaft rotation speed detection sensor 18 Each of the machine output shaft rotational speed signals P8 is input to an electronic control circuit section 22 that includes an interface section 19, a CPU 20, and a memory 21 as main components.

Furthermore, the amount of depression of the accelerator pedal 23 operated by the driver, that is, the accelerator opening degree, is detected by the accelerator opening detection sensor 24, the depression state of the brake pedal 25 is detected by the brake operation detection sensor 26G, and further, , the shift position of the shift lever 27 is detected by the shift 1 lever position detection sensor 28, and the gradient of the road surface is detected by the gradient sensor 55, and an accelerator opening signal PI corresponding to the amount of depression of the accelerator pedal 23 is generated.

Brake operation signal P3. obtained when the brake pedal 25 is depressed. A shift lever position date signal P7 corresponding to the position of the shift lever 27 and a slope signal P9 corresponding to the road surface slope are sent to the electronic control circuit section 2, respectively.
2 is input.

Further, the electronic control circuit section 22 includes - the above-mentioned various signals P1 to
P9 Jin' - In addition, obtained from the auxiliary equipment operation detection sensor 56, which detects whether the auxiliary equipment 57, such as an air conditioner, which is operated by the driving force from the engine 1, is in an operating state or a non-operating state. Auxiliary machine IJJ signal PIO is input.

Then, the electronic control circuit unit 22 outputs various control signals 31 . S2. S3,34. S5 and S6 are sent.

FIG. 3 shows an example of a gear ratio control device for a continuously variable transmission according to the present invention, to which the device is applied to control a clutch 7 and a switching gear disposed in a power transmission system from the engine 1 to the driving wheels 12. Gear train 8. 1 schematically shows the entire electronically controlled continuously variable transmission device including a continuously variable transmission 9 and an electronic control circuit section 22.

Here, various control signals 81 to S from the electronic control circuit section 22
6, the clutch connection control signal S1 is transmitted to the clutch control valve 29.
In order to energize the connection solenoid 30 of the clutch control valve 29, the clutch cutoff control signal S2 energizes the cutoff solenoid 31 of the clutch control valve 29, and the shift amplifier control signal S3 energizes the speed increase solenoid 33 of the speed change control valve 32. The downshift control signal S4 sends the line pressure control signal S5 to the line pressure control valve 37 to energize the deceleration solenoid 34 of the speed change control valve 32 with a predetermined duty. A throttle control signal S6 is supplied to the throttle actuator 4 to operate the throttle actuator 4 to adjust the opening degree of the throttle valve 3.

And Tarafuchi actuator 41. The continuously variable transmission a9 and the shift actuator 44 include the above-mentioned clutch control valve 29. The shift lever 27 is set to reverse R and neutral N by the speed change control valve 32 and the driver's manual operation.
, Drive D, and Low (2), the hydraulic oil is sucked from the oil tank through the filter 35 and discharged by the oil pump 36 through the shift control valves 43 that are controlled by being switched to the respective shift positions of , Drive D, and Low ■. It is supplied through each oil channel.

The electronically controlled continuously variable transmission, which is controlled by supplying hydraulic oil in this way, is operated by the engine 1 as described below.
It is configured such that the output of the drive wheel 12 can be transmitted to the drive wheels 12 and the related control can be performed.

】0 That is, the rotation of the output shaft 6 of the engine 1 is first caused by the rotation of the output shaft 6.
The signal is intermittently pressure-connected to a flywheel 38 provided at the end of the output shaft 6, and is transmitted to a clutch 7 that rotates coaxially with the output shaft 6. This clutch 7 has a friction plate 39 that presses against the flywheel 38, and a diaphragm-shaped clutch spring 40 to which a pressing plate that presses the friction plate 39 is fixed, and the clutch connection control signal S1 is transmitted to the clutch control valve. When the oil is sent to the connection solenoid 30 of the clutch actuator 29, the connection solenoid 30 is turned on by II iff, and as a result, the hydraulic oil is supplied from the open boat to the crunch actuator 41, and the piston moves inside the spring. It moves against the elastic force and rotates the lever 42 counterclockwise. As a result, the clutch spring 40 in the open state is moved to the closed state, pressing the friction plate 39, and the clutch 7 is brought into the connected state. Thereby, the rotation of the output shaft 6 of the engine 1 is transmitted to the output side of the clutch 7.

Further, when the clutch disconnection control signal S2 is sent to the disconnection solenoid 31 of the clutch control valve 29,
The cutoff solenoid 1'31 is turned on by iiJ+E41, and the operating pressure oil is discharged from the thalassodia actuator 41, and the piston is returned by the elasticity of the spring inside the solenoid, and the clutch spring 40 is opened. As a result, the flywheel 38 of the friction plate 39
The pressing state of the clutch 7 is released, and the clutch 7 is placed in a disengaged state. In this state, the rotation of the output shaft 6 of the engine 1 is not transmitted to the output side of the clutch 7.

Further, a clutch connection control signal S is sent to the connection solenoid 30 and cutoff solenoid 31 of the clutch control valve 29.
1 and clutch disconnection control signal S2, the opening port of the clutch control valve 29 is closed and the piston in the Thalassochia actuator 41 is maintained in its immediately previous state, so that the friction plate 39 is closed. The suppressed state appearing in the flywheel 38 is maintained.

The output side of the clutch 7 that operates in this manner transmits the rotation of the output shaft 6 of the engine 1 to the input shaft 16 of the continuously variable transmission 9 in accordance with the above-mentioned respective shift positions of the shift lever 27. A switching gear train 8 is provided. In this switching gear train 8, when the shift lever 27 is placed in the drive D or low I position, the piston of the shift actuator 44 moves in the direction D in the figure, and the output shaft 14 of the clutch 7 moves.
A gear 46 provided on the input shaft 16 of the continuously variable transmission 9 engages with a forward gear 45 fixed to the forward gear 45 to move the input shaft 16 of the continuously variable transmission 9 in the opposite direction to the output shaft 14 of the clutch 7. Rotate it. On the other hand, when the shift lever 27 is placed in the reverse R position, the piston of the shift actuator 44 moves in the R direction in the figure, and the gear 47 provided on the input shaft 16 of the continuously variable transmission 9 moves toward the output shaft of the clutch 7. 14, and engages with an idler gear 49 that is engaged with a reverse gear 48 fixed to the
The input shaft 16 of the continuously variable transmission 9 is rotated in the opposite direction to that of the drive D described above, that is, in the same direction as the output shaft 14 of the clutch 7. Furthermore, when the shift lever 27 is placed in the neutral N position, the piston of the shift I actuator 44 is held in the center of the cylinder, and the rotation of the output shaft 14 of the clutch 7 is transmitted to the input shaft 16 of the continuously variable transmission a9. It is done so that it is not done.

The continuously variable transmission 9 to which the rotation of the output shaft 14 of the clutch 7 is transmitted includes an input shaft 16 that rotates coaxially with the output shaft of the switching gear train 8, and a drive that rotates integrally with the input shaft 16. It has a pulley 50, a driven boob IJ 52 to which rotation of the drive boob IJ 50 is transmitted via a heald 51, and an output shaft 10 that rotates integrally with the driven boob IJ52.

The drive boo IJ50 includes a movable conical plate 50a and a fixed conical plate 5.
The movable conical plate 50a and the fixed conical plate 50b have their conical surfaces facing each other to form a V-shaped pulley groove.

The movable conical plate 50a is provided with a cylinder chamber 50C behind it, and can slide in the axial direction so as to approach or separate from the fixed conical plate 50b depending on the state of supply of hydraulic oil to the cylinder chamber 50c. Yes, there is also a fixed conical plate 50
b is fixed to the input shaft 16. On the other hand, the driven Boo'J
52 also has the same configuration as the drive pulley 50 described above,
A V-shaped pulley groove is formed by the movable conical plate 52a and the fixed conical plate 52b, and the movable conical plate 52a
It is possible to slide in the axial direction so as to be close to the fixed conical plate 52b depending on the supply state of the working pressure oil to the cylinder chamber 52C installed later. It is fixed.

A V-bell I-51 is stretched over each pulley groove formed in the drive pulley 50 and the driven pulley 52, whereby the rotation of the drive pulley 50 is transmitted to the driven pulley 52. Then, the rotation of the driving pulley 50 is controlled by the driven pulley 52.
When transmitting data to the V heald 5, which is determined by the width of the pulley groove of the driving pulley 50,
The rotation ratio between the drive pulley 50 and the driven pulley 52 can be changed by changing the rotation radius of the first driven pulley 52 and the second.

The width of the pulley grooves of the drive boob IJ 50 and the driven boob IJ 52 can be changed by changing the width of the pulley grooves of the respective movable conical plates 50a and 52.
The sliding control of the movable conical plates 50a and 52a is performed every time a is slid in the axial direction. This is performed by the shift control valve 32 which receives S4. That is, the shift up control signal S3 from the electronic control circuit section 22 is applied to the speed increasing solenoid 3 of the speed change control valve 32.
3, the speed-increasing solenoid/noise 133 is intermittently energized and turned on/off, thereby causing the cylinder chamber 50c of the drive boolean IJ50 to be turned on and off in accordance with the control duty of the shift-up control signal S3. While the working pressure oil is supplied, the working pressure oil is removed from the cylinder chamber 52c of the driven pulley 52. On the other hand, when the downshift control signal S4 is supplied to the deceleration solenoid 34, the deceleration solenoid 134 is intermittently excited. turned on and off,
As a result, the working pressure oil is supplied to the cylinder chamber 52C of the driven pulley 52 in accordance with the control duty of the lift-down control signal S4, and the working pressure oil is removed from the cylinder chamber 50c of the Q-driving pulley 50. Furthermore, when both the speed increase solenoid 33 and the deceleration solenoid 34 are turned off, the supply and removal of hydraulic oil to and from the cylinder chambers 50c and 52C of the drive pulley 50 and the driven pulley 52, respectively, is stopped.

Therefore, when the speed increasing solenoid 33 is turned on and off by the shift 1 to up control body S3, the movable conical plate 50a is moved in a direction approaching the fixed conical plate 50b, and the movable conical plate 50a The width of the pulley groove formed by the fixed conical plate 50b is reduced, and the radius of rotation of the heald 51 on the drive pulley 50 side is expanded. At the same time, the movable conical plate 52a is moved in a direction away from the fixed conical plate 52b, and the width of the pulley groove formed by the movable conical plate 52a and the fixed conical plate 52b is expanded. The turning radius on the driven boob IJ 52 side is reduced. Therefore, the gear ratio in the continuously variable transmission 9 becomes small. On the other hand, when the deceleration solenoid l'34 is turned on/off by the downshift control signal S4, the width of the pulley groove of the drive pulley 50 is expanded, contrary to the above case, and The radius of rotation on the driving pulley 50 side is reduced, and at the same time, the rotation radius on the driven pulley 52 side is reduced.
The width of the pulley groove is reduced, and the rotation radius of the heald 51 on the driven pulley 52 side is expanded. Therefore, in this case, the gear ratio of the continuously variable transmission 9 is determined to be positive.

Furthermore, the speed increasing solenoid 33 and the speed increasing solenoid 34
On the other hand, when neither the shift amplifier control signal S3 nor the shift down control signal S4 is sent out and each solenoid is turned off, the width of the pulley groove of each of the driving pulley 50 and the driven pulley 52 is Therefore, the respective rotation radii of the belt 51 on the driving pulley 50 side and the driven pulley 52 side are maintained, and the gear ratio in the continuously variable transmission 9 is changed to the speed increasing solenoid 33.
And the deceleration solenoid 34 is kept at the state immediately before it was turned off.

In this way, by changing the supply state of hydraulic oil to the cylinder chambers 50c and 52c of the drive boob IJ 50 and the driven pulley 52, respectively, the speed change lL can be changed continuously. In the transmission 9,
The greater the required driving force, the more it is necessary to increase the pressing force of the movable conical plates 50a and 52a against the V-belt 51 to increase the heald transmission force by the V-belt 51 (transmission torque capacity of the V-belt 51). There is. Therefore, in this example, the hydraulic pressure of the working pressure oil supplied from the oil pump 36 to the cylinder chamber 50c or 52C via the speed change control valve 32, that is, the line pressure is
Line pressure control valve 3 receiving line pressure control signal S5 from
7. That is, the line pressure control valve 37 is configured to be able to change the amount of oil that passes through it and is discharged, depending on the level of the line pressure control signal S5 supplied to the solenoid 37a, for example. In this case, the higher the level of the line pressure control signal S5 is, the more the amount of oil discharged is reduced and the line pressure is lowered.

1- In an example of the gear change control device for a continuously variable transmission according to the present invention configured as described above, the electronic control circuit unit 22 causes the flo-sotor valve 3 to perform throttle actuation uniquely in accordance with the amount of depression of the accelerator pedal 23. 4, and the gear ratio of the continuously variable transmission 9 is normally controlled in accordance with the shift characteristics shown in the shift diagram as shown in FIG. 10 mentioned above. .

Here, for example, if the vehicle is running at a constant speed with a constant accelerator opening and the air conditioner or other auxiliary a57 is activated or deactivated, no special control is required. (If not, hereafter referred to as the case of no Hil+ control)
As mentioned above, large fluctuations in the driving force transmitted from the engine 1 to the drive wheels 12 may occur, causing problems such as the vehicle speed undesirably decreasing or increasing. There is.

Therefore, in this example, the electronic control circuit unit 22 changes the auxiliary equipment 851 such as an air conditioner from a non-operating state to an operating state due to a change in the auxiliary equipment operation signal I) 10 inputted from the auxiliary equipment operation detection sensor 56. Alternatively, the switching from the operating state to the non-operating state, that is, the occurrence of a load fluctuation on the engine 1, is detected, and a shift is sent to the speed change control valve 32 for a predetermined period from the time when the load fluctuation occurs. Up control signal S3 b L, <4; t: The duty of the downshift control signal S4 is set such that the speed of change in the gear ratio of the continuously variable transmission 9 is small, for example, when almost no load fluctuation occurs on the engine 1. Adjust so that it is smaller than when it is not present.

As shown in the figure, when the auxiliary equipment operation signal P10 inputted from the auxiliary equipment operation detection sensor 56 changes, that is, from when a load change to the engine 1 occurs, the signal is sent to the speed change control valve 32 for a predetermined period of time. The duty of the shift amplifier control signal S3 or the shift down control signal S4 is made small, and the speed change speed of the continuously variable transmission 9 is made small, so that the continuously variable transmission 9 is reduced due to the trajectory fluctuation with respect to the engine 1. When the human shaft rotational speed 1'Jp decreases or increases by 1'Jp, the gear change operation (upshift or downshift) of the continuously variable transmission 9, which changes to follow the dirt, is performed at a relatively slow speed. . As a result, sudden fluctuations in the driving force transmitted from the engine 1 to the drive wheels 12 are suppressed, and the decrease or increase in vehicle speed is made relatively gradual.

As mentioned above, for example, when the vehicle is running with a constant accelerator opening, the auxiliary equipment 57 such as an air conditioner changes from a non-operating state to an operating state, or from an operating state to a non-operating state. The auxiliary machine operation signal P10. in the case where the change in load on the engine 1 occurs due to switching. Changes in the human power shaft rotational speed Np, gear ratio, and vehicle speed of the continuously variable transmission 9 are shown in FIG. 4A.

In B, C, and D, the results are as shown in comparison with the uncontrolled case (indicated by dashed lines in FIG. 4B, C, and D).

First, when the auxiliary machine 57 is switched from the non-operating state to the operative state, the auxiliary machine operating signal PIO is activated as shown in FIG.
At time t1), the input shaft rotational speed Np changes from a level representing an OFF state to a level representing an ON state, as shown in FIG. 4B, and immediately after this, as shown in FIG. Accordingly, the speed change of the continuously variable transmission 9 is increased, but at this time, in this example, the duty of the downshift control signal P4 is made smaller than in the case of no control, so that the duty ratio shown in FIG. As shown in , since the speed ratio change speed is smaller than that in the case of no control, the speed change operation of the continuously variable transmission 9 is completed at a later point in time (t2) than the time point (t2) at which it would end in the case of no control. finish. For this reason, from engine 1 to drive wheel 1
As a result, as shown in the fourth diagram, the decrease in vehicle speed becomes more gradual than in the case without control.

On the other hand, when the auxiliary machine 57 is switched from the production J state to the non-operating state, as shown in FIG. 4A, the auxiliary machine operating signal PI
At time t3), as shown in FIG. Figure 4C
As shown in , the gear ratio of the continuously variable transmission 9 is accordingly decreased, but in this example, the duty of the shift control signal S3 is made smaller than in the case of no control. , as shown in FIG. 4B, since the speed of change of the gear 1L is smaller than that in the case of no control, the time (t) at which the shift operation of the continuously variable transmission 9 ends in the case of no control
4) Finish at a later point. Therefore, in this case too,
Fluctuations in the driving force transmitted from the engine 1 to the drive wheels 12 are suppressed, and as shown in the fourth diagram, the increase in vehicle speed becomes more gradual than in the case without control.

1”j to the engine when the vehicle as described above is running.
A series of controls including control when the fluctuation is 4 times are performed based on the operation of the CPU 20 of the power control circuit section 22. An example of a program executed by the CP tJ 20 is shown in FIG. , will be explained with reference to flowchart I shown in FIGS. 6 and 7.

First, as shown in Figure 5, after starting the process [
Perform initial jiJl settings for each part using jO, then process 6
First of all, 1 of each! Input the data obtained based on the signal obtained from the sensor and proceed to process 62.
In step 2, program program J for clutch control is executed 7, and then in process 63, a program ri for gear ratio control is executed, and the process returns to process 61.

An example of a program for clutch control executed in the above-described process 62 is as shown in FIG. 1. After the start, in decision 70, it is determined whether the shift lever 27 is currently in the neutral range (N range) position, and the shift lever 27 is in the neutral range (N range). If the vehicle speed flag is in the position shown in FIG. The solenoid 31 is turned on and the connection solenoid 30 is turned off. Thereby, the clutch 7 is brought into the disconnected state.

If it is determined in decision 70 that the shift lever 27 is not in the neutral range position, then decision 73 determines that the current vehicle speed V is greater than a preset predetermined vehicle speed Va. Determine whether or not. Here, the vehicle speed Va is set to a vehicle speed at which there is a high risk of engine stoppage, and the vehicle speed V is set to such a vehicle speed ■
If it is determined that the speed is greater than δ, the vehicle speed flag is reset in the subsequent process 74 and the process proceeds to decision 75.

In decision 75, it is determined whether the change Ne' in the engine speed Ne is positive or negative. If the change Ne' in the engine speed Ne is positive, in decision 76, the engine speed Ne is changed to the clutch output. It is determined whether the shaft rotation speed is greater than the shaft rotation speed NC.

If it is determined that the engine speed Ne is greater than the clutch output shaft speed Nc, a clutch connection control signal S1 is sent to the connection solenoid F' 30 of the clutch control valve 29 in process 77, and the connection solenoid 30 is activated. At the same time, the cutoff solenoid 31 is turned on. This causes the friction plate 39 of the clutch 7 to
8 is forced into a state where clutch 7 is pressed, transmission of clutch 7]・
The torque capacity gradually increases. Also, in Decision 76,
If it is determined that the engine rotational speed Ne is smaller than the clutch output shaft rotational speed Nc, the process proceeds to process 79;
In process 79, clutch connection control signal S1 and clutch connection control signal S1
The connection solenoid 30 and the cutoff solenoid 31 are both turned off.This causes the friction plate 39 of the clutch 7 to suppress the flywheel 38 from the current state. Therefore, the transmission one herk capacity of the clutch 7 is maintained as it is.

On the other hand, in decision 75, engine speed Ne
If it is determined that the amount of change Ne' in If the number Ne is smaller than the clutch output shaft rotational speed NC, the process proceeds to process 77. This results in
Similarly to the above, the transmission torque capacity of the clutch 7 gradually increases. If it is determined in decision 78 that the engine speed Ne is not smaller than the clutch output shaft speed Nc, the process proceeds to process 79, in which both the connection solenoid 30 and the cutoff solenoid 1 and 31 are in the OFF state, as described above. be made into

If it is determined in the above-described decision 73 that the current predetermined vehicle speed ■ is lower than the vehicle speed Va, the process proceeds to decision 80, where it is determined whether the accelerator pedal 23 is on, that is, whether the accelerator pedal 23 is being depressed. If it is determined that the accelerator pedal 23 is in the on state, the process advances to decision 75, and the flow continues as shown in the above.

On the other hand, if it is determined in decision 80 that the accelerator pedal 23 is not in the on state, a decision is made in decision 81 to determine whether the vehicle speed flag is in the set state. is decision 82
Then, it is determined whether the brake pedal 25 is in the on state, that is, whether the brake pedal 25 is being depressed. If it is determined that the brake pedal 25 is in the on state, the process advances to decision 83. If it is determined in decision 81 that the vehicle speed flag is not set, the process proceeds to process 72, in which the cutoff solenoid 31 is turned on and the connection solenoid 31 is turned off, as described in section 1.

Then, in decision 83, engine rotation 13
It is determined whether Ne is below a predetermined value, for example 1500 rpm. Here, the engine rotation speed is 150 rpm
is the rotation speed that may cause the engine to stop when the brake pedal 25 is on. If the engine rotation speed Ne is not 1500 rpm or less, the process proceeds to decision 75, and the following steps are performed as described in -. Go with the flow. As a result of the engine speed decision 82, if it is determined that the brake pedal 25 is not in the on state, the process proceeds to decision 84, where it is determined whether the engine speed Ne is below a predetermined value, for example, 11000 rpm. Decide whether or not. Here, the engine speed is 1
1000 rpm is a rotation speed that may cause the engine to stop when the brake pedal 25 is in the OFF state, and if the engine rotation speed Ne is not 11000 rpm or less, the process advances to decision 75, and the flow as described above is followed. Proceed with On the other hand, the engine speed Ne is 10QOr
If it is less than or equal to pm, proceed to process 71 and proceed as follows.
Proceed according to the flow described above.

Next, an example of a program for speed ratio control executed in process 63 of the program shown in FIG. 5 is as shown in FIG. Here, first, after the start I, in process 101, the change α'' in the accelerator opening degree α is calculated based on the accelerator opening degree signal P1, and then the process proceeds to decision 102, in which the change amount α'' in the accelerator opening degree α is calculated based on the shift lever position signal P7. It is determined whether or not it is in the low range (L range), and if it is determined that it is in the low range, the process proceeds to process 103.
In step 3, a constant load accelerator opening degree A is added to the accelerator opening degree α, and the added accelerator opening degree α+ is set as a new accelerator opening degree α, and then the process proceeds to process 104.

On the other hand, if it is determined in decision 102 that it is not in the low range, the process proceeds to process 104 without passing through process 103, and here, the speed change characteristic map does not exhibit the speed change characteristics as shown in FIG. Based on the accelerator opening degree α obtained in process 103, the target input shaft rotation speed TNp of the continuously variable transmission 9 is set. Then, in the subsequent process 105, the input shaft rotation speed Np set in process 104 is set to the target manual shaft rotation RT.
It is determined whether the rotation speed is greater than Np plus the allowable rotation speed B, and if it is determined that it is large, process 1
Proceed to step 07, set coefficient C to -1 and make decision 10.
Proceed to step 8.

In decision 108, α' mDX, which is the maximum value of the changes α' in the accelerator opening up to that point, is
Change α in accelerator opening α calculated in process 101
If it is determined that it is smaller, in process 109, the change α' in the accelerator opening is set as the maximum value α' max, and then in process 1
On the contrary, if it is determined that the size is not small, the process advances to step 110 without going through process 109. On the other hand, if it is determined in the two consecutive decisions 106 that the input shaft rotational speed Np'l<TNp4-B is not greater, the process proceeds to decision 113. Here, it is determined whether the input shaft rotation speed Np is smaller than the rotation speed obtained by subtracting the allowable rotation speed B from the target input shaft rotation speed TNp, and if it is small, the coefficient C is increased by +1 in process 114.
108, process 109, and decision 110 in sequence, and in process 111, the target input times, and in each of the above-mentioned decisions 106 and 113, the input axis is If it is determined that the rotational speed Np is not larger than TNp10B and not smaller than TNp-B, the input shaft rotational speed Np is
The change α in the accelerator opening α that matches or is close to the shift characteristic line X shown in the figure, meaning that it has converged to the so-called control dead zone Clear the maximum value α'max of ゛ to O,
Proceed to decision 112.

Then, in decision 112, when the accessory operation signal PIO from the accessory operation detection sensor 56 changes,
That is, the built-in timer, which is started when the off-state level changes from the on-state level to the on-state level, or vice versa, determines whether or not Lll remains low for a predetermined period of time.

Here, as described above, when the auxiliary equipment 57 such as an air conditioner is shifted from the non-operating state to the operating state or from the operating state to the non-operating state, the engine rotation speed Ne, and therefore, due to load fluctuations on the engine 1, The input shaft rotation speed Np of the continuously variable transmission 9 increases or decreases, but if the accelerator opening α is constant at that time, the input shaft rotation speed Np
In order to maintain the rotation speed according to the accelerator opening α, the electronic control circuit unit 22 transmits a shift up control signal S3 or a shift down control signal S4 having a predetermined control duty as described later to the shift control valve 32. speed increasing solenoid 3
3 or to the deceleration solenoid 34 to cause the continuously variable transmission 9 to perform a speed change operation. In this case, the time required for the speed change operation of the continuously variable transmission 9 is changed by the control duty of the shift amplifier control signal S3 or the shift/down control signal S4. The gear change operation of the transmission 9 is performed slowly.

Therefore, the above-mentioned predetermined time t11 is set to leave a sufficient margin even when the continuously variable transmission 9 performs a gradual speed change operation, and also allows the driving force to be transmitted from the engine 1 to the drive wheels 12 due to load fluctuations on the engine 1. The time is selected at a time that does not interfere with the speed change operation of the continuously variable transmission 9 when there is no fluctuation in the speed.

Therefore, the predetermined time t□ selected in this way is
On the other hand, if it is determined that the predetermined time t11 has elapsed, the process 117 is enlarged.

Then, proceed to process 119 and process 118
It is determined whether the speed ratio change speed calculated in is positive or not, and if it is not positive, the process proceeds to process 121, and the speed increase solenoid 33 of the speed change control valve 32 Shift amplifier control signal S with control duty
3 to turn the dirt on and off, and also turn off the deceleration solenoid 34 of the speed change control fffll valve 32. As a result, the gear ratio is made small, and the downshift control signal S4 having the above-mentioned control duty is supplied to the deceleration solenoid 34 of the control valve 32, and it is turned on and off. The quick release solenoid 33 is in the off state. As a result, the gear ratio is set to "inverted", and the rotational speed Np of the input shaft G increases.

The responsiveness of the continuously variable transmission [9] that operates according to the characteristics is made good, and the operation is performed at the speed of the auxiliary equipment operation signal PIO. Fluctuations in the driving force transmitted to the vehicle are reduced.

- In the above example, the control duty of the shift amplifier control signal S3 or the shift down control signal S4 sent to the speed change control valve 32 is set to be small for a predetermined period from the time when a load change occurs to the engine 1, Although the speed ratio change speed of the continuously variable transmission 9 is made small, and as a result, rapid fluctuations in the driving force transmitted from the engine 1 to the drive wheels 12 are suppressed, instead of such control, For a predetermined period of time from when a load change occurs on the engine 1,
Control may be performed to stop the gear ratio control for the continuously variable transmission 9. In the case of other examples of the gear ratio control device for a continuously variable transmission according to the present invention, similarly to the above-mentioned example,
Rapid fluctuations in the driving force transmitted from the engine 1 to the drive wheels 12 can be suppressed.

Next, still another example of the gear ratio control device for a continuously variable transmission according to the present invention will be described.

In this example, the driving force of engine 1 is
When the auxiliary equipment 57 such as an air conditioner is activated, the electronic control circuit section 22 detects the auxiliary equipment operation detection sensor 5.
A change in the auxiliary equipment operating signal PLO obtained from 6 is detected from a level representing an OFF state to a level representing an ON state, or vice versa, and the throttle actuator 4 shown in FIG. control signal S6
, the opening of the throttle valve 3 is automatically increased by a predetermined angle from the current position, and the output of the engine 1 is increased, or the opening of the flotrotor valve 3 is further increased by a predetermined angle from the current position. It is automatically reduced, causing the engine 1 to reduce its output.

As described above, an idle amplifier mechanism is known as a device that increases the output of the engine 1 when the auxiliary machine 57 is activated, and in this case, the increase in the output of the engine 1 due to the idle amplifier mechanism is The loss is said to be greater than the loss caused by the auxiliary machine 57.

In this example, the shift characteristic line X that falls on the shift characteristic map that shows the shift characteristic as shown in FIG. or vice versa, to change the ranges of the shift amplifier region and shift down region in the speed change characteristic.

The operation of this example will be described below with reference to FIG. 8 in comparison with the case without control. First, when the auxiliary machine 57 is switched from the non-operating state to the operative state, the auxiliary machine operating signal PIO changes from a level representing an OFF state to a level representing an ON state, as shown in the 8th national. The electronic control circuit section 22 detects this, and the engine 1
In order to increase the output of the Flotor actuator 4, as shown in FIG. 8B, the Flotor control signal S6
is supplied to further open the flo-sotor valve 3 by a predetermined angle from the position corresponding to the accelerator opening degree α. As a result, as shown in FIG. 8C, in the case of no control (dotted chain line), the input shaft rotational speed Np of the continuously variable transmission 9 increases by -J-, and then returns to approximately steady rotation at time t2. In this example, the speed change characteristic line X as shown in FIG. The gear ratio of the continuously variable transmission 9 is controlled in accordance with the shift characteristic line X after this movement. Therefore, as shown in Figure 8, the gear ratio is increased, contrary to the case of no control (dotted chain line), and as shown in Figure 8C, the input shaft rotation speed Np is approximately the steady rotation speed. will be maintained. As a result, fluctuations in the driving force transmitted from the engine j to the drive wheels 12 are suppressed, and the vehicle speed is kept substantially constant, as shown in FIG. 8E4.

On the other hand, when the auxiliary machine 57 is switched from the operating state to the non-operating state, the auxiliary machine operating signal P
At a time point E3) when LO changes from a level representing an on state to a level representing an off state, the electronic control circuit section 22
In order to detect this and reduce the output of the engine 1, the supply of the throttle control signal S6 to the throttle actuator 4 is stopped as shown in FIG.
Return the throttle valve 3 to the position corresponding to the accelerator opening degree α. As a result, as shown in FIG.
p decreases and then returns to a substantially steady rotational speed at time t2, but in this example, the speed change characteristic line X as shown in FIG. The position is returned to the original position shown by the solid line, and the speed ratio of the continuously variable transmission 9 is controlled according to the speed change characteristic line X after this return, so the speed ratio is as shown in Figure 8. , in the case of no control (dotted chain line), 1 is reduced inversely, and the eighth
As shown in Figure C, the input shaft rotational speed Np is maintained at a substantially steady rotational speed. As a result, from the engine 1 to the driving wheel 12
Fluctuations in the driving force transmitted to the vehicle are suppressed, and the vehicle speed is kept substantially constant as shown in FIG. 8E.

A series of controls including i+ and ++ control when a load change occurs on the engine while the vehicle is running as described above is performed based on the operation of the electronic control circuit section 220 CPU 20. An example of a program executed by the computer will be described with reference to flowchart 1 shown in FIG.

Here, first, after the start, in decision 150, it is determined whether or not the shift lever position signal P7 is in the low range (■7 range).If it is determined that it is in the low range, the process advances to process 151; A constant load accelerator opening A is applied to the accelerator opening α.
is added, and the added accelerator opening degree (α+A) is set as the new accelerator opening degree α, followed by process 152.
Proceed to. On the other hand, if it is determined in decision 150 that the range is not in the low range (L range), the process proceeds to process 152 without passing through process 151.

In process 152, the target human power shaft rotation speed TNp of the continuously variable transmission a9 is calculated from the accelerator opening α obtained in process 151 based on the speed change characteristic map, which does not represent the speed change characteristics as shown in FIG. 10 described above. Then proceed to decision 153. Then, in decision 153, the auxiliary equipment operation signal P
It is determined whether or not IO is input, and if it is input, the supplementary air conditioner etc. [57] is in the operating state, and the flow control valve 3 is in the throttle actuator 4.
Since the accelerator opening is further opened to a predetermined opening from the position corresponding to the accelerator opening α, and the engine output is increased, the process proceeds to process 154 and the target input shaft rotation vJ is
, the predetermined rotational speed y is added to TNp and the result is 7, which is newly calculated as 1.
Dingeon 1 by setting the standard input shaft rotation speed TNp.
Proceed to step 55.

Here, the predetermined rotational speed y is determined according to the input shaft rotational speed Np which increases when the double complement m57 is in the operating state and the flo-sotor valve 3 is opened at a predetermined angle by the slot actuator 4. TNp
+y corresponds, for example, to the input shaft rotation speed Np of the continuously variable transmission 9 corresponding to the accelerator opening αa of the shifted shift characteristic line X'2 shown by the chain line in FIG. If it is determined in process 153 that the auxiliary equipment operation signal PIO is not input, the process proceeds to decision 155 without going through process 154, and input shaft rotational speed N
It is determined whether p is smaller than the target input shaft rotation speed "FNp", and if it is, the process proceeds to process 157 where the downshift control signal S4 is sent to the speed change control valve 32 in order to keep the speed change ratio at the same level. [Deceleration solenoid] is sent to S34 and this flow ends.On the other hand, if it is determined in decision 155 that the input shaft rotation speed Np is not smaller than the target input shaft rotation speed TNp, the process proceeds to process 156 to increase the gear ratio. To begin with, the shift amplifier control signal S3 is sent to the speed increase solenoid 1:33 of the speed change control valve 32, and this flow ends.

In the above example, load fluctuations on the engine 1 are caused by auxiliary equipment such as an air conditioner that operates in response to the driving force from the engine 1, but the present invention is not limited to this, and the load fluctuation on the engine Even if the variation is due to, for example, the road surface slope, the above-mentioned case can be applied in the same manner. In such a case, based on the gradient signal P9 obtained from the gradient sensor 55, the electronic control circuit section 22
It is sufficient to configure the continuously variable transmission 9 to change the speed change characteristics according to the magnitude of the road surface gradient to control fluctuations in the driving force transmitted from the engine 1 to the drive wheels 12.

(Effects of the Invention) As is clear from the above description, according to the shift control device for a continuously variable transmission according to the present invention, the continuously variable transmission mechanism provided in the power transmission path from the engine to the wheels of the vehicle can be controlled. The gear ratio is controlled according to predetermined gear shift control characteristics, and for example, when the vehicle is running at a constant speed with a constant accelerator opening, auxiliary equipment such as an air conditioner, road slope, etc. When a load change occurs on the engine due to a change in the load on the engine, the control signal sent from the gear ratio control means to the gear ratio adjustment means changes the speed change characteristics of the continuously variable transmission mechanism, thereby increasing the driving force transmitted from the engine to the wheels. Since the fluctuations are automatically suppressed, it is possible to avoid a situation where the vehicle speed undesirably increases or decreases due to load fluctuations, and the driver is not forced to operate the troublesome accelerator adjustment means.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration diagram of a gear ratio control device for a continuously variable transmission according to the present invention, and FIG. 2 is a drive control section of a vehicle to which an example of the gear ratio control device for a continuously variable transmission according to the present invention is applied. FIG. 3 is a schematic configuration diagram showing an example of the gear ratio control device for a continuously variable transmission according to the present invention together with an electronically controlled continuously variable transmission to which the same is applied; FIG. 4 are characteristic diagrams used to explain the operation of the example shown in FIG. 3, FIGS. 5 and 6.
7 and 7 are flowcharts showing an example of an operation program in the electronic control circuit section used in the example shown in FIG. 3, and FIG. 8 is another example of the gear ratio control device for a continuously variable transmission according to the present invention. Figure 9 is a characteristic diagram used to explain the operation of the IJ in the electronic control circuit used in the example shown in Figure 8.
Flowchart showing an example of an operation program, No. 10
The figure is a speed change diagram for explaining speed ratio control of the continuously variable transmission mechanism. In the figure, 1 is the engine, 3 is the throttle valve, 7 is the clutch, 9 is the continuously variable transmission, 22 is the electronic control circuit, 23 is the accelerator pedal, 24 is the accelerator opening detection sensor 4'',
32 is a speed change control valve, 55 is a gradient sensor, 56 is an auxiliary equipment operation detection sensor, and 57 is an auxiliary equipment.

Claims (1)

[Claims] A gear ratio adjusting means for changing the gear ratio of a continuously variable transmission mechanism provided in a power transmission path from the engine to the wheels of the vehicle, a load fluctuation detecting means for detecting load fluctuations on the engine, and from the load fluctuation detecting means. control means for sending a control signal to the gear ratio adjusting means based on the obtained signal in order to suppress fluctuations in the driving force transmitted from the engine to the wheels when a load fluctuation occurs on the engine; A gear ratio control device for a continuously variable transmission.