JPH052858B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention has a continuously variable transmission and a clutch that are interposed between an engine and drive wheels, and uses these to detect the operating state of the engine, etc. The present invention relates to an electronically controlled continuously variable transmission which is controlled by an electronic control means based on a detection signal obtained by the above.

(Prior Art) Conventionally, in a transmission device used in an automobile, the gear ratio of each gear range, such as 1st to 5th gear, is set to a constant value in advance, so the driver can In order to obtain the required vehicle speed etc. with appropriate or efficient engine output, it is necessary to perform frequent switching between each gear range, and this switching operation requires intermittent switching between the engine and transmission. This also adds to the need to operate the clutch mechanism, which is troublesome. In addition, there are automatic transmissions that use a torque converter that uses fluid as a power transmission medium so that each gear range can be changed automatically, but transmissions that use this torque converter are prone to fluid slippage. Therefore, there is a problem that there is considerable power transmission loss.

For this reason, a continuously variable transmission that can automatically and continuously change the gear ratio, for example, connects two pulleys with V-shaped grooves with a V belt and changes the width of the pulley grooves. , V-belt pulley continuously variable transmissions with variable gear ratios have been proposed. The output of the engine is transmitted to the wheels, which are driven bodies, through such a continuously variable transmission,
In automobiles employing an electronically controlled continuously variable transmission in which the continuously variable transmission is controlled using electronic control means, the driver is freed from the hassle of clutch operation. However, even in such a case, the clutch mechanism is not unnecessary, and is useful when starting or stopping the vehicle, or when the driver shifts the shift lever from the neutral range to the drive range or reverse range. When switching, etc., intermittent control is required for the clutch mechanism to transmit the engine output to the continuously variable transmission, so the clutch mechanism is automatically controlled within the electronically controlled continuously variable transmission. It is being understood. Regarding the control of the clutch mechanism associated with such a continuously variable transmission, for example, as described in Japanese Patent Laid-Open No. 52-98862, in the clutch mechanism associated with a V-belt pulley type continuously variable transmission, Proposals have been made to detect the tension of the V-belt and to bring the clutch mechanism into the connected state when the tension of the V-belt is sufficiently increased.

In a car equipped with an electronically controlled continuously variable transmission in which the gear ratio is automatically controlled as described above,
Usually, the gear ratio of the continuously variable transmission is controlled such that the engine rotational speed, and therefore the input rotational speed of the continuously variable transmission, are uniquely determined by the throttle valve opening. That is, the gear ratio is controlled so that a constant engine output is obtained with respect to the value of the throttle valve opening. For example, control is performed such that the relationship between the throttle valve opening Th and the input shaft rotational speed Np of the continuously variable transmission follows the speed change characteristics as shown in FIG.
In the shift characteristics shown in Figure 1, the area labeled "down" is a downshift area, and the area labeled "up" is a throttle valve opening detected by the electronic control means for the continuously variable transmission. Detection signals from the input rotation speed detection means of the continuously variable transmission and the continuously variable transmission are supplied, and a control output corresponding to each detection signal is sent from the electronic control means to the gear ratio adjustment section of the continuously variable transmission.

Further, the basic acceleration pattern of the automobile in such a case is as shown in FIG. Figure 2A
, the gear ratio and throttle valve opening are plotted on the vertical axis, and time t is plotted on the horizontal axis, and in Fig. 2B, the rotation speed is plotted on the vertical axis, and time t is plotted on the horizontal axis. , the period from the start of the accelerator depression operation until the engine reaches a steady rotation speed is defined as region P, and the period thereafter is defined as region Q, and the gear ratio H and throttle valve opening are defined as
The solid lines represent changes in Th and the input shaft rotation speed Np of the continuously variable transmission, and the broken lines represent changes in the output shaft rotation speed No of the continuously variable transmission. Here, for example,
When the driver depresses the accelerator, the throttle valve opening Th increases in proportion to the amount of accelerator depression in region P, and as a result, the engine output shaft rotation speed Ne increases, causing the continuously variable transmission to The input shaft rotation speed Np and gear ratio H increase, and therefore the output shaft rotation speed No of the continuously variable transmission gradually increases.
Changes in the acceleration of the vehicle at this time are relatively small. In addition, in region Q, the throttle valve opening
Although Th is constant, the gear ratio H gradually decreases, so the output shaft rotational speed No of the continuously variable transmission increases and the vehicle speed increases.

However, in cars equipped with such electronically controlled continuously variable transmissions, even if the driver suddenly presses down on the accelerator in an attempt to accelerate suddenly, the car does not adjust to the accelerator opening due to the pedal operation. It takes a relatively long time to reach the corresponding vehicle speed V compared to the accelerator depression speed, and as a result, drivers are dissatisfied with the car's responsiveness to accelerator operation, resulting in poor acceleration performance and power performance. This resulted in a feeling of unsatisfactory performance, and furthermore, there were problems such as repeated depressing of the accelerator, which worsened fuel efficiency.

(Object of the Invention) In view of the above, the present invention transmits driving force from an engine installed in an automobile to driving wheels using a clutch means and a continuously variable transmission, and operates the clutch means. The state and gear ratio of the continuously variable transmission are controlled based on control signals sent from the electronic control means, and when the vehicle is required to accelerate rapidly, that is, due to the driver's accelerator operation, etc. When the engine load suddenly increases, the change in driving force from the engine is quickly transmitted to the drive wheels in response, improving the acceleration performance and power performance of the vehicle, and improving fuel efficiency accordingly. The purpose is to provide an electronically controlled continuously variable transmission.

(Structure of the Invention) The electronically controlled continuously variable transmission according to the present invention is connected between an automobile engine and drive wheels to which the torque of the engine is transmitted, and continuously changes an input/output torque ratio. a continuously variable transmission, a gear ratio adjusting means for changing the input/output torque ratio of the continuously variable transmission, and a clutch means for selectively interrupting or connecting torque transmission from the engine to the continuously variable transmission; The first one detects the engine load condition.
a second detection means for detecting the rotational speed of at least one rotating body that rotates by being transmitted with the torque of the engine or drive wheels; and electronic control means for sending a control signal to the gear ratio adjusting means in light of predetermined speed change control characteristics, and for sending a control signal to the clutch means to control the operation of the clutch means. The electronic control means disables the clutch means when the engine load suddenly increases, adjusts the gear ratio of the continuously variable transmission to bring the input side rotation speed of the clutch means to the target rotation speed, and then closes the clutch means. from the disconnected state to the connected state.

By doing this, when the load on the engine increases rapidly, the torque transmitted from the engine to the output side of the clutch means can be rapidly increased, making it possible to rapidly accelerate the vehicle.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows an outline of a drive control section of an automobile to which an example of an electronically controlled continuously variable transmission according to the present invention is applied. In the figure, reference numeral 1 denotes a reciprocating piston type engine, in which an intake passage 2 is provided with a throttle valve 3 for controlling fuel supply, and the throttle valve 3 is opened and closed by a throttle actuator 4. The opening degree is detected by a throttle position sensor 5. Note that the end 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. A fuel injection valve is disposed at 2d.

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

Further, an engine rotation speed detection sensor 13 detects the rotation speed of the output shaft 6 of the engine 1, a clutch output shaft rotation speed detection sensor 15 detects the rotation speed of the output shaft 14 of the clutch 7, and an input shaft of the continuously variable transmission 9. 16
A transmission input shaft rotation speed detection sensor 17 detects the rotation speed of the continuously variable transmission 9, and a transmission output shaft rotation speed detection sensor 18 detects the rotation speed of the output shaft 10 of the continuously variable transmission 9, and therefore the vehicle speed. Installed in place. Then, the throttle valve position signal from the aforementioned throttle position sensor 5 is transmitted.
P ₅ , engine output shaft rotation speed signal P ₂ from the engine rotation speed detection sensor 13 mentioned above, clutch output shaft rotation speed signal P ₄ from the clutch output shaft rotation speed detection sensor 15 , transmission input shaft rotation speed detection sensor 1
The transmission input shaft rotation speed signal P ₆ from the transmission output shaft rotation speed detection sensor 18 and the transmission output shaft rotation speed signal P ₈ from the transmission output shaft rotation speed detection sensor 18 are transmitted to the interface section 19 .
and is input to an electronic control circuit section 22 that includes a CPU 20 and a memory 21 as main components.

Further, the amount of depression of the accelerator pedal 23 operated by the driver, that is, the accelerator opening is detected by the accelerator opening detection sensor 24, and the depression state of the brake pedal 25 is detected by the brake operation detection sensor 24.
6, and furthermore, the shift position of the shift lever 27 is detected by the shift lever position detection sensor 2.
8, an accelerator opening signal P ₁ corresponding to the amount of depression of the accelerator pedal 23, a brake operation signal P ₃ obtained by depression of the brake pedal 25, and a brake operation signal P 3 corresponding to the position of the shift lever 27. Shift lever position signal _P7 is
Each is input to the electronic control circuit section 22.

Based on the signals P ₁ to P ₈ obtained and input from each sensor, the electronic control circuit section 22 outputs various control signals S ₁ , S ₂ , S ₃ , S ₄ , S ₅ , S ₆ is output.

FIG. 2 shows an electronically controlled continuously variable transmission according to the present invention, which includes the clutch 7, the switching gear train 8 forming the torque transmission switching means, the continuously variable transmission 9, and the electronic control circuit section 22. An example of the outline is shown below. Here, the A solenoid ₃₀ of the clutch control valve 29 receives the clutch control signal _S1 among the various control signals S1 to _S6 from the electronic control circuit section 22, and the A solenoid 30 of the clutch control valve 29 receives the clutch control signal _S2 and performs the clutch control. Valve 29 B
The solenoids 31 are energized, respectively, and the clutch 7
The supply state of hydraulic oil to is controlled. Further, in response to the shift control signal S ₃ , the C solenoid 33 of the shift control valve 32 is energized, and in response to the shift control signal S ₄ , the D solenoid 34 of the shift control valve 32 is energized. The supply status of hydraulic oil is controlled,
Its gear ratio is controlled.

Furthermore, the shift control valve 43 is controlled by switching the shift lever 27 to the forward D, neutral N, and reverse R shift positions by manual operation by the driver, and the clutch control valve 29 described above.
and the speed change control valve 32 are supplied with operating pressure oil from an oil tank via a filter 35 and a hydraulic pump 36. The line pressure supplied from the hydraulic pump 36 is adjusted by a pressure reducing valve 37 that receives a line pressure control signal _S5 from the electronic control circuit section 22.

Furthermore, the throttle actuator 4 operates in response to the throttle control signal _S6 , thereby
The opening degree of the throttle valve 3 is adjusted.

The continuously variable transmission that is controlled by being supplied with hydraulic oil in this manner is configured to be able to transmit the output of the engine 1 to the drive wheels 12 and perform related control as described below. ing.

That is, the rotation of the output shaft 6 of the engine 1 is first
A flywheel 38 provided at the end of the output shaft 6
The signal is transmitted to a clutch 7 which is intermittently pressure-connected to the output shaft 6 and 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 control signal _S1 is transmitted to the clutch control valve. 29
When the oil is sent to the A solenoid 30, the A solenoid 30 is energized and turned on, and as a result, the hydraulic oil is supplied from the open port to the clutch actuator 41, and inside the clutch actuator 41, the piston is moved by the elasticity of the spring. Move against it and press lever 4.
Rotate 2 counterclockwise. As a result, the clutch spring 40 in the open state is moved to the closed state and presses the friction plate 39, thereby bringing the clutch 7 into the connected state. As a result, the rotation of the output shaft 6 of the engine 1 is transmitted to the output side of the clutch 7.

Also, the clutch control signal _S2 is transmitted to the clutch control valve 2.
When sent to the B solenoid 31 of No. 9, B
The solenoid 31 is energized and turned ON, hydraulic oil is discharged from the clutch actuator 41, and the piston is returned by the elasticity of the spring inside the clutch actuator 41, so that the clutch spring 40 is opened. As a result, the pressing state of the friction plate 39 against the flywheel 38 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.

Furthermore, the A solenoid 3 of the clutch control valve 29
When neither the clutch control signals S ₁ nor S ₂ are sent to the 0 and B solenoids 31, the open port of the clutch control valve 29 is closed, and the piston in the clutch actuator 41 is returned to its previous state. Therefore, the pressing state of the friction plate 39 against the flywheel 38 is maintained.

On the output side of the clutch 7 that operates in this way,
To the input shaft 16 of the continuously variable transmission 9, the shift lever 27
A switching gear train 8 forming a torque transmission switching means is provided so that the rotation of the output shaft 6 of the engine 1 is transmitted according to the forward D, neutral N, and reverse R shift positions. This switching gear train 8
When the shift lever 27 is placed in the forward position D, the forward range is assumed, and the piston of the shift actuator 44 moves in the direction D in the figure.
A gear 46 provided on the input shaft 16 of the continuously variable transmission 9 engages with a forward gear 45 fixed to the output shaft 14 of the clutch 7, so that the input shaft 16 of the continuously variable transmission 9
is rotated in the opposite direction at the same rotation speed as the output shaft 14 of the clutch 7. On the other hand, when the shift lever 27 is placed in the reverse position R, the reverse range is assumed, and the piston of the shift actuator 44 moves in the R direction in the figure. The driven gear 47 engages with an idle gear 49 that is engaged with a reverse gear 48 fixed to the output shaft 14 of the clutch 7, so that the input shaft 16 of the continuously variable transmission 9,
In the case of forward movement D described above, the clutch 7 is rotated in the opposite direction, 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, it assumes a neutral range, and the piston of the shift actuator 44 is held in the center of the cylinder, and the output shaft 14 of the clutch 7 is prevented from rotating. This is done so that the signal is not transmitted to the input shaft 16 of the gear transmission 9.

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 pulley 52 to which rotation of the drive pulley 50 is transmitted via a V-belt 51, and an output shaft 10 that rotates integrally with the driven pulley 52.

The drive pulley 50 has a movable conical plate 50a and a fixed conical plate 50b.
0a and the fixed conical plate 50b have their conical surfaces facing each other to form a V-shaped pulley groove. A cylinder chamber 50c is provided behind the movable conical plate 50a.
Fixed conical plate 50b depending on the supply state of hydraulic oil to
The fixed conical plate 50b is axially slidable toward or away from the input shaft 16. The fixed conical plate 50b is fixed to the input shaft 16. On the other hand, the driven pulley 52 has the same configuration as the driving pulley 50 described above, and a V-shaped pulley groove is formed by a movable conical plate 52a and a fixed conical plate 52b, and the movable conical plate 52a is located behind the movable conical plate 52a. Depending on the state of supply of working pressure oil to the provided cylinder chamber 52c, it can be slid in the axial direction so as to approach the fixed conical plate 52b, and the fixed conical plate 52b is fixed to the output shaft 10.

A V-belt 51 is stretched over each of the pulley grooves formed in the drive pulley 50 and the driven pulley 52, thereby transmitting the rotation of the drive pulley 50 to the driven pulley 52. And drive pulley 5
When transmitting zero rotation to the driven pulley 52, the rotation radius of the V-belt on the drive pulley 50 side is determined by the width of the pulley groove of the drive pulley 50, and the driven drive of the V-belt is determined by the width of the pulley groove of the driven pulley 52. By changing the rotation radius on the pulley 52 side, the rotation ratio between the driving pulley 50 and the driven pulley 52 can be changed.

The width of each pulley groove of the driving pulley 50 and the driven pulley 52 is changed by sliding the respective movable conical plates 50a and 52a in the axial direction. A speed change control valve 32 is provided for this purpose. This speed change control valve 32 is connected to the electronic control circuit section 22.
C is turned on and off by the shift control signal _S3 from
A solenoid 33 and a D solenoid 34 which is turned on and off by the speed change control signal _S4 are provided.
When the C solenoid 33 is turned on,
While supplying working pressure oil to the cylinder chamber 50c of the driving pulley 50, the cylinder chamber 5 of the driven pulley 52
When the D solenoid 34 is turned on, the hydraulic oil is supplied to the cylinder chamber 52c of the driven pulley 52 and the hydraulic oil is removed from the cylinder chamber 50c of the drive pulley 50. do. Further, when both the C solenoid 33 and the D solenoid 34 are turned off, the supply and removal of hydraulic oil to the cylinder chambers 50c and 52c of the driving pulley 50 and the driven pulley 52, respectively, is stopped.

In the shift control valve 32 having the above-mentioned role, when the C solenoid 33 is turned on by the shift control signal _S3 , the hydraulic oil from the hydraulic pump 36 is supplied from the supply port to the cylinder chamber of the drive pulley 50. As a result, the movable conical plate 50a is moved in a direction approaching the fixed conical plate 50b, and the width of the pulley groove formed with the fixed conical plate 50b is reduced, and the drive pulley 50 of the V-belt 51 is The turning radius on the side increases. Also,
At the same time, the cylinder chamber 52 of the driven pulley 52
The working pressure oil filled in c is removed from the discharge port, thereby moving the movable conical plate 52a in a direction away from the fixed conical plate 52b,
The width of the pulley groove formed by the fixed conical plate 52b is expanded, and the radius of rotation of the V-belt 51 on the driven pulley 52 side is reduced. Therefore, the continuously variable transmission 9
The gear ratio becomes small. On the other hand, when the D solenoid 34 is turned on by the speed change control signal _S4 , the working pressure oil from the hydraulic pump 36 is supplied from the supply port to the cylinder chamber 52c of the driven pulley 52, contrary to the above case. At the same time, the working pressure oil is removed from the cylinder chamber 50c of the drive pulley 50, the width of the pulley groove of the drive pulley 50 is expanded, and the rotation radius of the V-belt 51 on the drive pulley 50 side is reduced. 5
The width of the second pulley groove is reduced, and the rotation radius of the V-belt 51 on the driven pulley 52 side is expanded. Therefore, in this case, the gear ratio in the continuously variable transmission 9 is made large. Furthermore, C solenoid 3
3 and D solenoid 34, a shift control signal
When neither S ₃ nor S ₄ 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 maintained at the width immediately before it. , the rotation radii of the V-belt 51 on the drive pulley 50 side and the driven pulley 52 side are maintained, and the gear ratio in the continuously variable transmission 9 is adjusted to the C solenoid 33 and the D solenoid 3.
4 is kept at the state immediately before it was turned off.

In an example of the electronically controlled continuously variable transmission according to the present invention having the above-described configuration, changing the gear ratio of the continuously variable transmission 9 and operating the clutch 7 are controlled by a control signal S ₁ from the electronic control circuit section 22. - This is done based on _S4 , but especially when the engine load increases rapidly due to accelerator operation etc., the clutch 7 is disengaged and the gear ratio of the continuously variable transmission 9 is adjusted to reduce the clutch output. Shaft rotation speed Nc, that is, continuously variable transmission 9
A distinctive feature is that the clutch 7 is operated from the disconnected state to the connected state after the input shaft rotational speed Np has reached the target rotational speed.

Hereinafter, the operation of the example of the electronically controlled continuously variable transmission according to the present invention described above when the automobile is started down will be explained. For example, when a vehicle is running, a driver may suddenly depress the accelerator pedal 23 in order to overtake or otherwise attempt to accelerate the vehicle rapidly by performing a kick-down motion. During such a kickdown, response performance of the automobile is strictly required, and acceleration performance, especially dynamicity with slight shock, is desired. For this purpose, the time of area P in FIG. 2 mentioned above,
That is, the time required for the engine 1 to reach a steady rotation speed is shortened, and the acceleration is increased in a short time.
Although it is necessary to increase the speed of change of the gear ratio,
In the above example, control for this purpose is performed as described below.

When the automobile shifts to a rapid acceleration state, the load state of the engine 1 increases rapidly, but in the above example, this is detected by the accelerator opening α, and as shown in Fig. 5A.
As shown in FIG.
4 inputs to the electronic control circuit 22 that it is the time of kick-down, and therefore the electronic control circuit section 22 controls the B solenoid 31 of the clutch control valve 29.
The clutch 7 is switched from the connected state to the disconnected state by sending out a clutch control signal _S2 that turns on the clutch 7. At this time, the electronic control circuit unit 22 calculates the target input shaft rotation speed TNp of the continuously variable transmission 9 for the accelerator opening α based on the predetermined gear ratio control characteristics, and also calculates the target input shaft rotation speed TNp of the continuously variable transmission 9 at that time. input shaft rotation speed
Np (same as the clutch output shaft rotation speed Nc) is calculated, and the gear ratio of the continuously variable transmission 9 is controlled so that the current input shaft rotation speed Np approaches the target input shaft rotation speed TNp. For example, when the actual input shaft rotation speed Np of the continuously variable transmission 9 is smaller than the target input shaft rotation speed TNp, the electronic control circuit section 22 turns on the D solenoid 34 of the speed change control valve 32. Sends a shift control signal _S4 . Drive pulley 50 of continuously variable transmission 9
At the same time as the width of the pulley groove of the driven pulley 52 is expanded, the width of the pulley groove of the driven pulley 52 is reduced, and due to this variation, the rotation radius of the V-belt 51 on the drive pulley 50 side is reduced, and the rotation of the driven pulley 52 side is reduced. The radius is expanded to increase the input shaft rotation speed of the continuously variable transmission 9.
Np is increased. Here, since the clutch 7 is in the disconnected state, the transmission torque capacity of the clutch 7 suddenly drops to zero, as shown in FIG. 5B, and the engine output decreases as shown in FIG. 5C. The shaft rotation speed Ne suddenly increases as the external load is removed. At the same time, as shown in FIG. 5D, the gear ratio H when the clutch 7 is in the disengaged state changes at a steeper slope than the gear ratio H' when the clutch 7 is in the engaged state (indicated by the chain line in the figure). The input shaft rotation speed Np of the continuously variable transmission 9 is
Rotation speed when clutch 7 is engaged (Fig. 5C)
Although the target input shaft rotational speed TNp is reached earlier than the target input shaft rotational speed TNp (indicated by a chain line in the figure), the rate of increase is smaller than the rate of increase of the input shaft rotational speed Np. Therefore, the difference between the engine output shaft rotation speed Ne and the input shaft rotation speed Np of the continuously variable transmission 9 increases from the time when the clutch 7 is placed in the disengaged state. When the target input shaft rotation speed TNp of the continuously variable transmission 9 and the input shaft rotation speed Np match, the electronic control circuit section 2
The A solenoid 30 of the clutch control valve 29 is turned on by the clutch control signal _S1 from the clutch control valve 29, and the clutch actuator 41 is actuated to connect the clutch 7. When the clutch 7 operates in the connected state, as shown in FIG. 5B and C, the transmission torque capacity of the clutch 7 increases while the engine output shaft rotation speed Ne increases; When the rotational speed Ne passes the peak and decreases, a shelf-like staircase is formed to maintain a predetermined value.

As a result, as shown in FIG. 5E, the acceleration G of the automobile once drops when the clutch 7 is disengaged, but the electronic control circuit 22 increases the gear ratio of the continuously variable transmission 9. After that, the clutch 7 is controlled to maintain a constant value, and when the clutch 7 operates to the connected state, it rises at a steep slope, and the transmission torque capacity of the clutch 7 is maintained at a constant value. When the vehicle is running, the acceleration G is also assumed to maintain a constant value.

As mentioned above, once the clutch 7 is brought into the disengaged state at the time of kick-down, the engine output shaft rotational speed Ne rapidly increases, and the gear ratio changing speed of the continuously variable transmission 9 can also be increased. And continuously variable transmission 9
When the input shaft rotation speed Np of the engine 1 matches the target input shaft rotation speed TNp, by shifting the clutch 7 to the connected state, the transmission torque capacity of the clutch 7 from the output shaft 6 of the engine 1 can be rapidly increased in a short period of time. Therefore, the rate of increase (gradient) of the acceleration G in region P in FIG. 2 is increased, and by adjusting the transmission torque capacity of the clutch 7, it is possible to add some flavor to the shock.

A series of controls as described above are carried out by the electronic control circuit section 2.
This is done based on the operation of the CPU 20 in 2.
An example of a program executed by such a CPU 20 will be explained with reference to flowcharts shown in FIGS. 6, 7, and 8.

First, as shown in FIG. 6, after starting, initial settings are made for each part in process 60, then a program for clutch control is executed in process 61, and then a gear ratio and throttle control is executed in process 62. The program for controlling the opening degree of the tutle valve is executed and the process returns to process 61.

An example of a program for clutch control executed in the above-mentioned process 61 is as shown in FIG. Here, after the start, the shift lever is currently 27 at day 70.
It is determined whether the shift lever 27 is in the neutral range (N range) position, and if the shift lever 27 is in the neutral range position, the vehicle speed is adjusted in process 71. Set flag FV to reset state and continue process 7
2, a clutch control signal _S2 is sent to the B solenoid 31 of the clutch control valve 29, turning the B solenoid 31 on and the A solenoid 30 off. As a result, the clutch 7 is placed in the disconnected state.

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

In process 75, the amount of depression of the accelerator pedal 23, that is, the accelerator opening degree α, is read, and in the subsequent decision 76, it is determined whether the accelerator opening degree α is in a kick-down (KD) region where it is large. If it is in the kick-down area, the process advances to decision 77; if it is not in the kick-down area, the kick-down flag KD' is set to 0 (reset) in process 78, and the process advances to decision 81. Decision 77 determines the target input shaft rotation speed of the continuously variable transmission 9 for the accelerator opening α.
It is determined whether the absolute value of the difference between TNp and the current input shaft rotation speed Np is smaller than a predetermined value ε. As a result, if the absolute value of the difference between the target input shaft rotation speed TNp and the current input shaft rotation speed Np is smaller than ε, the kick down flag KD' is set to 1 in process 80.
(set) and proceed to decision 79. on the other hand,
When the absolute value of the difference between the target input shaft rotational speed TNp and the input shaft rotational speed Np is greater than or equal to ε, the process advances to decision 79, where it is determined whether the kick down flag KD' is 0, that is, in the reset state. If the kick down flag KD' is 0, that is, in the reset state, the process proceeds to process 72, where the A solenoid 30 of the clutch control valve 29 is turned off;
The B solenoid 31 is turned on and the clutch 7 is placed in a disconnected state. On the other hand, Kitsuku Downflag
If KD′ is 1, that is, the process is in the set state, process 9
Go to 1.

Decision 91 determines whether the change Ne' in the engine output shaft rotation speed Ne is positive or negative. If the change Ne' in the engine output shaft rotation speed Ne is positive, the decision 92 determines whether the change Ne' in the engine output shaft rotation speed Ne is positive or negative. It is determined whether the rotational speed Ne is greater than the clutch output shaft rotational speed Nc. If it is determined that the engine output shaft rotation speed Ne is greater than the clutch output shaft rotation speed Nc, in process 93 the clutch control valve 2
A clutch control signal _S1 is sent to the A solenoid 30 of No. 9 to turn the A solenoid 30 on and the B solenoid 31 off. As a result, the friction plate 39 of the clutch 7 is connected to the flywheel 3.
8 is pressed, the clutch 7 is brought into the connected state, and the transmission torque capacity of the clutch 7 gradually increases.

On the other hand, if it is determined at decision 91 that the change Ne' in the engine output shaft rotation speed Ne is negative, the process proceeds to decision 94, where the engine output shaft rotation speed Ne is lower than the clutch output shaft rotation speed Nc. If the engine output shaft rotation speed Ne is smaller than the clutch output shaft rotation speed Nc, the process proceeds to process 93. As a result, the transmission torque capacity with the clutch 7 in the connected state gradually increases as described above. If it is determined in decision 94 that the engine output shaft rotation speed Ne is not smaller than the clutch output shaft rotation speed Nc, the process proceeds to process 95.
Clutch control signals S ₁ and S ₂ are both prevented from being sent out, thereby maintaining the current pressing state of the friction plate 39 of the clutch 7 against the flywheel 38, and therefore, the transmission torque capacity of the clutch 7 remains the current state. maintained.

If it is determined at decision 73 that the current vehicle speed V is not greater than vehicle speed Va, the process proceeds to decision 80, where the accelerator pedal 23 is
It is determined whether or not the accelerator pedal 23 is in the on state, that is, the accelerator pedal 23 is depressed. If it is determined that the accelerator pedal 23 is in the on state, the process proceeds to decision 75, and the following flow follows as described above. .

On the other hand, the accelerator pedal is 23 at decision 80.
If it is determined that the vehicle speed flag FV is not on, decision 81 determines whether the vehicle speed flag FV is set. If the vehicle speed flag FV is set, decision 82 determines whether the brake pedal 25 is turned on. status, i.e. brake pedal 2
5 is depressed, and if it is determined that the brake pedal 25 is in the on state, the process advances to decision 83.

Then, in decision 83, it is determined whether the engine output shaft rotation speed Ne is less than a predetermined value, for example, 1500 rpm. Here, the engine output shaft rotation speed 1500 rpm is a rotation speed that may cause the engine to stop when the brake pedal 25 is on, and if the engine output shaft rotation speed Ne is not below 1500 rpm, the process 7
Step 5 follows, and the flow continues as described above. If the engine output shaft rotational speed Ne is 1500 rpm or less, the process proceeds to process 71, and the process proceeds as described above.

If the decision 82 determines that the brake pedal 25 is not in the on state, the process proceeds to decision 84, where it is determined whether the engine output shaft rotation speed Ne is below a predetermined value, for example 1000 rpm. do. Here, the engine output shaft rotation speed 1000 rpm is the rotation speed that may cause the engine to stop when the brake pedal 25 is in the OFF state, and if the engine output shaft rotation speed Ne is not below 1000 rpm, the process 75
The process proceeds as described above. On the other hand, if the engine output shaft rotational speed Ne is 1000 rpm or less, the process proceeds to process 71, and the flow proceeds as described above.

Next, an example of a program for speed change control executed in process 62 of the program shown in FIG. 6 is as shown in FIG. After the start, the accelerator opening degree α is read in process 100 based on the accelerator opening signal P ₁ , and in the subsequent decision 101, the shift lever 2
7 is placed in the low range (L range) position. In addition, in Figure 4,
Although the shift lever 27 is not shown to be in the low range position, the shift lever 27 is capable of being in the low range position. If the shift lever 27 is not in the low range position, the process proceeds to process 103; if the shift lever 27 is in the low range position, the process goes through process 102 and then proceeds to process 103.
Proceed to step 3. In process 102, process 100
The accelerator opening degree α1 is obtained by adding a preset supplementary opening degree C to the accelerator opening degree α read in .

Next, in process 103, the target input shaft rotation speed TNp of the continuously variable transmission 9 is calculated for the accelerator opening degree α or α obtained in this way. Then, in the next process 104, the current input shaft rotation speed Np of the continuously variable transmission 9 is read based on the transmission input shaft rotation speed signal _P6 , and in the subsequent decision 105, the current input shaft rotation speed Np is read in the process 104. It is determined whether the current input shaft rotation speed Np is greater than the target input shaft rotation speed TNp. As a result of this judgment, if it is large, the process 106
A shift control signal _S30 is sent to the C solenoid 33 to turn the C solenoid 33 on, and the D solenoid 34 to turn off. Thereby, the speed change control valve 32 controls the speed ratio of the continuously variable transmission 9 to be small, and as a result, the input shaft rotation speed Np of the continuously variable transmission 9 is reduced. On the other hand, as a result of the determination at decision ₁₀₅ , if the input shaft rotation speed Np is lower than the target input shaft rotation speed TNp, the process ₁₀₇ causes the D solenoid 3 of the speed change control valve 32 to
A shift control signal _S4 is sent to turn the D solenoid 34 on and the C solenoid 33 off. As a result, the speed change control valve 32 controls the continuously variable transmission 9.
As a result, the input shaft rotation speed Np of the continuously variable transmission 9 is increased. In this way, the actual input shaft rotation speed Np of the continuously variable transmission 9 is made to match the target input shaft rotation speed TNp by the operation of process 10 ₆ or 10 ₇ , and the program for gear ratio control is ended. A process 61 for controlling the clutch by
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(Effects of the Invention) As is clear from the above description, according to the electronically controlled continuously variable transmission according to the present invention, the torque of the engine installed in the automobile is efficiently transmitted to the driving wheels via the continuously variable transmission. At the same time, when the engine load suddenly increases, the clutch is placed in the disconnected state, and the gear ratio of the continuously variable transmission 9 is adjusted to bring the output shaft rotation speed of the clutch to the target rotation speed, and then the clutch is placed in the disconnected state. When the vehicle is operated from the connected state to the connected state when a sudden acceleration is required, it is possible to increase the speed ratio change speed of the continuously variable transmission 9, and the speed of the transmission from the engine to the clutch output side can be increased. As a result, the vehicle can quickly respond to operations such as the driver stepping on the accelerator, improving the vehicle's acceleration performance, power performance, response performance, etc. be able to. Furthermore, by controlling the transmission torque capacity of the clutch, it is also possible to add dynamic performance with some shock.

[Brief explanation of drawings]

1 and 2 are diagrams used to explain the characteristics of the electronically controlled continuously variable transmission according to the present invention and the running pattern during acceleration of a vehicle equipped with a conventional electronically controlled continuously variable transmission. FIG. 3 is a schematic configuration diagram showing a drive control section of an automobile to which an example of the electronically controlled continuously variable transmission according to the present invention is applied, and FIG. 4 shows an example of the electronically controlled continuously variable transmission according to the present invention. A schematic configuration diagram, FIG. 5 is a characteristic diagram used to explain the operation of the example shown in FIG. 4, and FIGS.
2 is a flowchart showing an example of an operation program in an electronic control circuit section used in the example shown in the figure. In the figure, 1 is an engine, 7 is a clutch, 9 is a continuously variable transmission, 17 is a transmission input shaft rotation speed detection sensor,
22 is an electronic control circuit section, 23 is an accelerator pedal,
24 is an accelerator opening detection sensor, 29 is a clutch control valve, and 32 is a speed change control valve.

Claims (1)

[Claims] 1. A continuously variable transmission that is connected between the engine and the drive wheels to which the engine's torque is transmitted and that can continuously change the input/output torque ratio, and a continuously variable transmission that can change the input/output torque ratio of this continuously variable transmission. a clutch means arranged to selectively interrupt or connect torque transmission from the engine to the continuously variable transmission; and a first detection means for detecting a load condition of the engine. and a second device for detecting the rotational speed of at least one rotating body that is rotated by the torque of the engine or drive wheels.
and electronic control means for sending a control signal to the gear ratio adjusting means and to the clutch means based on the signals obtained from the first and second detecting means. Equipped with
The electronic control means shuts off the clutch means when the load on the engine increases rapidly, and adjusts the gear ratio of the continuously variable transmission to bring the output side rotation speed of the clutch means to the target rotation speed. The electronically controlled continuously variable transmission is characterized in that the clutch means is then operated from the disconnected state to the connected state.