JPH06109120A - Continuously variable transmission for vehicle - Google Patents

Abstract

PURPOSE:To prevent shocks of a vehicle attributable to the engine brake during the deceleration of the vehicle. CONSTITUTION:A clutch mechanism 4 to transmit the driving force of an engine, an output member to transmit the driving force to the driving wheels after speed change, an input side pulley device provided between the clutch mechanism 4 and the output member 8, and an output side pulley device 6 are provided. A continuously variable transmission 1 for the vehicle is provided with a transmission belt 7 to transmit the driving force of the input side pulley device 5 to the output side pulley device 6 and a speed change control device 28 to execute the speed change control by controlling the engagement pressure of the clutch mechanism 4, the pressure to be introduced into the input side pulley device 5, the pressure to be introduced into the output side pulley device 6 and the fuel injecting condition of the engine. In this continuously variable transmission 1, the speed change control device 28 sets the engine to the fuel injection controlling condition when the vehicle speed is extremely low and the accelerator pedal is not stepped on.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The continuously variable transmission according to the present invention is widely used as an automatic transmission for vehicles.

[0002]

2. Description of the Related Art As an automatic transmission for a vehicle, "Mira Service Manual Explanation" by Daihatsu Motor Co., Ltd .:
Some are described on page II-96 issued in March, 1990. This prior art transmission is an automatic transmission equipped with a torque converter. In this transmission,
When the engine speed is equal to or higher than the set value during deceleration, when the driver releases the accelerator pedal and the idle switch is turned on, the fuel injection device of the engine is set to the fuel cut control state to generate the engine brake.

However, in the case of a continuously variable transmission which is not equipped with a torque converter, when the fuel cut control is carried out in an extremely low speed range, an engine braking phenomenon appears prominently, which causes a great shock to the vehicle.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to prevent a vehicle shock caused by engine braking during deceleration of the vehicle.

[0005]

In order to solve the above-mentioned problems, in a first aspect of the present invention, a clutch mechanism for transmitting a driving force of an engine, an output member for transmitting a driving force after shifting to a driving wheel, An input side pulley device including an input side movable pulley and an input side fixed pulley installed between the clutch mechanism and the output member; an output side pulley device including an output side movable pulley and an output side fixed pulley; A transmission belt that transmits the driving force of the side pulley device to the output side pulley device, a shift position signal generator that generates a shift position signal that detects the position of the shift lever, and an accelerator signal that detects whether the accelerator is operating or not. An accelerator signal generator that generates a vehicle speed signal, a vehicle speed signal generator that generates a vehicle speed signal that detects a vehicle speed, the shift position signal, and the accelerator signal. Based on the vehicle speed signal and the vehicle speed signal, the engagement pressure of the clutch mechanism, the pressure for urging the movable pulley of the input side pulley device, the pressure for urging the movable pulley of the output side pulley device, and the fuel injection of the engine. In a continuously variable transmission for a vehicle equipped with a shift control device for performing shift control by controlling the state of the shift state, the shift position signal detects that the shift lever is in a position other than the P and N positions, and the accelerator signal is detected. Detects that the accelerator is not operating, and further detects that the vehicle speed signal is equal to or lower than a predetermined first speed value and is equal to or higher than a predetermined second speed value, the shift control device. Provides a continuously variable transmission for a vehicle, which sets the engine in a fuel injection control state.

Further, according to a second aspect of the present invention, a clutch mechanism for transmitting the driving force of the engine, an output member for transmitting the driving force after shifting to the driving wheels, and an input side installed between the clutch mechanism and the output member. An input side pulley device including a movable pulley and an input side fixed pulley, an output side pulley device including an output side movable pulley and an output side fixed pulley, and a driving force of the input side pulley device is transmitted to the output side pulley device Transmission belt, a shift position signal generator that generates a shift position signal that detects the position of the shift lever, an accelerator signal generator that generates an accelerator signal that detects activation / deactivation of the accelerator, and a vehicle speed A vehicle speed signal generating device for generating a vehicle speed signal, and a clutch detection for generating a clutch state detection signal for detecting completion of engagement of the clutch mechanism. Signal generator, the shift position signal, the accelerator signal, the vehicle speed signal, and the clutch state detection signal based on the engagement pressure of the clutch mechanism, the pressure for urging the movable pulley of the input side pulley device, In a continuously variable transmission for a vehicle equipped with a shift control device for performing shift control by controlling a pressure for urging a movable pulley of an output side pulley device and a state of fuel injection of an engine, the shift position signal is a shift lever. Is not in the P and N positions, and the accelerator signal detects that the accelerator is not operating,
Further, the vehicle speed signal is less than or equal to a predetermined first speed value,
Further, when the clutch state detection signal detects that the engagement of the clutch mechanism is completed, the shift control device puts the engine into a fuel injection control state, and a continuously variable transmission device for a vehicle is provided. .

[0007]

According to the above construction, the fuel cut control is not performed and the fuel injection control is performed in the extremely low speed region during deceleration, so that excessive engine braking does not occur and the shock of the vehicle can be prevented.

[0008]

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

FIG. 1 shows the structure of a continuously variable transmission 1 according to the present invention. In FIG. 1, a continuously variable transmission 1 includes a vibration absorbing device 2, and the vibration absorbing device 2 is attached to an engine (not shown) to transmit a driving force, and a flywheel 2a that is connected to the flywheel 2a and has a cushioning function. And a damper mechanism 2b. A clutch mechanism 4 includes a clutch 4a, a brake 4b, and a planetary gear 4c.
It consists of and. The clutch mechanism 4 is installed between the input member 3 and the fixed pulley 5b of the input side pulley device 5, and has an intermittent function between the input member 3 and the input side pulley device 5, and the continuously variable transmission 1. It has a function to switch between forward and backward. The rotational force of the engine transmitted to the input member 3 via the vibration absorbing device 2 is transmitted to the input side pulley device 5 via the clutch mechanism 4. The input side pulley device 5 includes a movable pulley 5a in addition to the fixed pulley 5b described above, and a pressure chamber 5c is provided on the right side of the movable pulley 5a in the drawing. 6 is an output side pulley device, and like the input side pulley device 5,
A movable pulley 6a and a fixed pulley 6b are provided, and a pressure chamber 6c is installed in contact with the movable pulley 6a. The input side pulley device 5 and the output side pulley device 6 are connected by a transmission belt 7, and by introducing appropriate pressures into the pressure chambers 5c and 6c, respectively, the movable pulley 5a,
The position of 6a is changed to change the contact radius of the transmission belt 7 with respect to each of the input side pulley device 5 and the output side pulley device 6 to realize a desired gear ratio. The rotational force after shifting, which is transmitted to the output side pulley device 6, is applied to the rotary gear 8 spline-fitted onto the output side fixed pulley 6b.
After being transmitted to the counter gear 9 via and being decelerated again,
It is transmitted to the differential device 11 via the rotary gear 10 to rotate the drive wheels of the vehicle (not shown).

Next, 21 is a shift sensor linked with a shift lever 22 for shifting the vehicle, 23 is an accelerator switch for detecting whether the accelerator pedal 24 is operating or not, 25 is an engine speed sensor, Reference numeral 26 is an input side pulley rotation speed sensor, and 27 is an output side pulley rotation speed sensor which functions as a vehicle speed sensor. Reference numeral 28 denotes a shift control device, which is a shift position signal detected by the shift sensor 21, an accelerator signal detected by the accelerator switch 23, an engine rotation speed signal detected by the engine rotation speed sensor 25, and the input side pulley. Based on the input side pulley rotation speed signal detected by the rotation speed sensor 26 and the vehicle speed signal detected by the output side pulley rotation speed sensor 27, the input side pulley pressure control signal, the output side pulley pressure control signal and the clutch engagement A combined pressure control signal is sent to the pressure control circuit device 29 to control the shifting of the continuously variable transmission 1.

Next, referring to FIG. 2, a method for controlling the shift of the transmission and a method for controlling the fuel injection state of the engine by the shift control device 28 will be described. When the vehicle is in a normal traveling state, the shift lever position is determined to be the D or S position at 31. Further, since the accelerator pedal 24 is actuated, when it is judged at 32 that the accelerator is on, the transmission is in the shift control state 38 and the engine is in the fuel injection control state 38, and the input side pulley device 5 is
An appropriate control pressure is introduced to the output side pulley device 6 to select a desired gear ratio, and an appropriate amount of fuel is supplied to the engine according to the running state. Next, when the vehicle is in the initial stage of the deceleration state, it is determined in 32 that the accelerator pedal is in the non-actuated state, and when it is determined in 33 that the vehicle speed is equal to or higher than the first set value, the transmission device is The control pressure to the input side pulley device 5 is reduced and the output side pulley device 6
The control pressure is increased to the deceleration control state 37 in which the shift to the LOW side progresses, and the engine enters the fuel cut control state 37 to limit the fuel supply. Next, when deceleration of the vehicle progresses and the vehicle speed is sufficiently reduced, it is determined in 33 that the vehicle speed is equal to or lower than the first set value, and in 34, the vehicle speed is set to the second set value that is lower than the first set value. When it is determined that the value is lower than the value, the transmission is set to the LOW fixed control state 35, the pressure in the pressure chamber 5c is drained, the engine is set to the idle control state, and the idle speed is kept constant.

Next, when the vehicle is in an extremely low speed state, 3
In 3 and 34, it is determined that the vehicle speed is between the first set value and the second set value (for example, about 5 km / h),
The transmission enters the deceleration control state 36, and the movement of the pulley toward the LOW side proceeds. However, since the engine is now in the fuel injection control state 36, the supply of fuel is not restricted and excessive engine braking does not occur.

Further, as described above, instead of determining in 34 whether the vehicle speed is lower than the second set value, as shown in 39, it is determined whether the clutch mechanism 4 is completely engaged. The detection signal may be used. In this case, an engine rotation speed sensor and an input side pulley rotation speed sensor may be used as the clutch detection signal generator,
Alternatively, the engagement pressure sensor of the clutch mechanism may be used.

[0014]

In the continuously variable transmission according to the present invention, even if the accelerator pedal is released at an extremely low speed, the engine is in the fuel injection control state, so that fuel supply is not restricted and excessive engine braking occurs. Therefore, a shock of the vehicle does not appear, and a continuously variable transmission for a vehicle having high comfort and safety can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram of a continuously variable transmission for a vehicle according to the present invention.

FIG. 2 is a control flowchart of a continuously variable transmission for a vehicle.

[Explanation of symbols]

1 continuously variable transmission 4 clutch mechanism 5 input side pulley device 6 output side pulley device 5a, 6a movable pulleys 5b, 6b fixed pulley 7 transmission belt 8 output member 21 shift sensor 23 accelerator switch 25 engine speed sensor 26 input side pulley rotation Speed sensor 27 Output side pulley rotation speed sensor 28 Shift control device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display area F16H 59:56 8009-3J

Claims (3)

[Claims] 1. A clutch mechanism for transmitting a driving force of an engine, an output member for transmitting a driving force after shifting to a driving wheel, an input side movable pulley and an input side fixed member installed between the clutch mechanism and the output member. An input side pulley device including a pulley, an output side pulley device including an output side movable pulley and an output side fixed pulley, a transmission belt for transmitting the driving force of the input side pulley device to the output side pulley device, and a shift A shift position signal generator that generates a shift position signal that detects the lever position, an accelerator signal generator that generates an accelerator signal that detects whether the accelerator is operating or not, and a vehicle speed that generates a vehicle speed signal that detects the vehicle speed. A signal generator, an engagement pressure of the clutch mechanism based on the shift position signal, the accelerator signal, and the vehicle speed signal; Vehicle equipped with a shift control device for performing shift control by controlling the pressure for urging the movable pulley of the input side pulley device, the pressure for urging the movable pulley of the output side pulley device, and the state of fuel injection of the engine In the continuously variable transmission for vehicle, the shift position signal detects that the shift lever is in a position other than the P and N positions, the accelerator signal detects that the accelerator is not operating, and the vehicle speed signal is predetermined. Is less than or equal to the first speed value and is greater than or equal to a predetermined second speed value, the shift control device puts the engine into a fuel injection control state. apparatus. 2. A clutch mechanism for transmitting a driving force of an engine, an output member for transmitting a driving force after shifting to a driving wheel, an input side movable pulley and an input side fixed member installed between the clutch mechanism and the output member. An input side pulley device including a pulley, an output side pulley device including an output side movable pulley and an output side fixed pulley, a transmission belt for transmitting the driving force of the input side pulley device to the output side pulley device, and a shift A shift position signal generator that generates a shift position signal that detects the lever position, an accelerator signal generator that generates an accelerator signal that detects whether the accelerator is operating or not, and a vehicle speed that generates a vehicle speed signal that detects the vehicle speed. A signal generator, a clutch detection signal generator that generates a clutch state detection signal that detects completion of engagement of the clutch mechanism, and the shifter. Based on the transmission position signal, the accelerator signal, the vehicle speed signal, and the clutch state detection signal, the engagement pressure of the clutch mechanism, the pressure for urging the movable pulley of the input side pulley device, the movement of the output side pulley device. In a continuously variable transmission for a vehicle equipped with a shift control device for performing shift control by controlling a pressure for urging a pulley and a fuel injection state of an engine, the shift position signal indicates that the shift lever is other than the P and N positions. Is detected, the accelerator signal detects that the accelerator is not operating, the vehicle speed signal is less than or equal to a predetermined first speed value, and the clutch state detection signal is the clutch mechanism. For the vehicle, wherein the shift control device puts the engine into a fuel injection control state when it is detected that the engagement of Variable transmission. 3. The clutch detection signal generator includes an engine rotation speed detection device for detecting an engine rotation speed and an input side pulley rotation speed detection device for detecting a rotation speed of the input side pulley device. Claim 2
Continuously variable transmission that satisfies the requirements