JPH06123353A - Speed change control method - Google Patents

Abstract

PURPOSE:To prevent the generation of a mechanical damage of a transmission by stopping the current carrying to a transmission driving motor when the rotating ratio is smaller than a determined value in the speed increasing process of the motor. CONSTITUTION:In a speed change control in which a control circuit 15 looks up a target ratio of a transmission stored in a memory on the basis of throttle opening and vehicle speed and drives a motor 6 on the basis of the target ratio looked up to control the driving pulley 2 of the transmission, the carrying of a driving current to the motor 6 is stopped, when the rotation ratio of the driving pulley 2 to a driven pulley 3 is judged smaller than a fixed value in the speed increasing process of the motor 6, and an abnormality is displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle shift control method.

[0002]

2. Description of the Related Art Conventionally, a target ratio of a transmission is determined by looking up a three-dimensional map showing a relationship between a throttle opening, a vehicle speed and a target ratio as shown in FIG. 1, and based on the target ratio. Motor for driving the transmission
Is being driven to control the transmission. This motor slides the movable pulley of the drive pulley of the transmission, and the rotation ratio changes according to the sliding position of the movable pulley. That is, the transmission is composed of a drive pulley and a driven pulley to which the rotation from the drive pulley is transmitted via a belt, and the shift control is performed from the output shaft of the driven pulley. Driving force is output. A pull position sensor is provided to detect the sliding position of the movable pulley, and the pull ratio is detected by the output signal of the pull position sensor. Further, in order to recognize the rotation ratio of the drive pulley and the driven pulley, a sensor for detecting the rotation speed of each shaft is provided.

[0003]

In the above-described conventional shift control device, if the pulley position sensor becomes abnormal and the pulley ratio becomes undetectable, the shift up is continued. Since the maximum ratio is reached, mechanical damage such as gear shifting components of the transmission and mo
Burner may occur.

Therefore, in the present invention, when the rotation ratio exceeds a predetermined value while the motor is in the speed increasing process, the motor is
The technical problem to be solved is to prevent the occurrence of mechanical damage such as burnout of the speed change components of the transmission and the motor by stopping the energization to.

[0005]

The technical means for solving the above-mentioned problems is to determine a target ratio of a transmission and drive a motor for driving the transmission based on the target ratio to change the transmission. In the speed change control method for controlling the pulley to reach the target ratio, the rotation ratio between the rotation of the drive pulley of the transmission and the rotation of the driven pulley in the speed increasing process of the motor. When it is determined that is smaller than a certain value, the supply of the drive current to the motor is stopped and the abnormality is displayed.

[0006]

In the above speed change control, a failure of the drive position sensor of the drive pulley occurs during the speed increasing process of the motor, making it impossible to detect the pulley ratio. If the rotation ratio between the rotation of the drive pulley and the rotation of the driven pulley of the transmission becomes smaller than a certain value, mechanical damage such as burnout of gear components of the transmission and the motor will occur. Therefore, the supply of the drive current to the motor is stopped, further shift up is stopped, and the abnormality is displayed.

[0007]

Next, an embodiment of the present invention will be described. Figure 2
Shows a control configuration of the continuously variable transmission 1 of the vehicle. In FIG. 2, a belt 4 is hung between the drive pulley-2 and the driven pulley-3 of the continuously variable transmission 1. The input shaft 2A of the drive pulley-2 is connected to an output mechanism of an engine (not shown), and the output shaft 3A of the driven pulley-3 is connected to a traveling drive system. A movable pulley 5 is slidably mounted on the drive pulley-2, and the rotational diameter of the belt 4 is variable depending on the sliding position of the movable pulley-5. Gear shift control 1 is controlled by controlling the sliding position of the movable pulley 5.

The movable pulley-5 of the drive pulley-2 is slid by a motor-6. That is, the output gear 7 attached to the output shaft of the motor 6 rotates the intermediate gear 8,
Further, in order to rotate the gear 10 attached to the end of the gear shaft 9A, the gear 9 at the other end is rotationally driven. As a result, the gear slider 11 that meshes with the gear 9 is also driven to rotate. The shaft portion of the slider 11 has a screw structure, and the rotation of the slider 11 moves the slider 11 in the pulley axial direction. Also, the slider 11 is the bearing 11
Since it is connected to the pulley 5 via A, the input shaft 2
Slide the movable pulley 5 along A.

A slider 11 meshing with the gear 9 has a position sensor for detecting the sliding position of the movable pulley 5.
12 are connected. This position sensor-12
Is configured so that the internal resistance changes with the movement of the slider 11, and as a result, a voltage signal corresponding to the sliding position of the movable pulley 5 connected via the bearing 11A is transmitted. Output. Therefore, this position sensor
Based on the voltage signal output from 12, the pre-ratio is detected.

A rotation sensor is provided on the outer peripheral portion of the input shaft 2A.
13 is provided, and a signal corresponding to the rotation speed of the input shaft 2A is output. Further, a rotation sensor-14 is arranged on the outer peripheral portion of the output shaft 3A, and a signal corresponding to the rotation speed of the output shaft 3A is output.

The position sensor-12 and the rotation sensors-13, 14 are connected to the control circuit 15, and the microcomputer incorporated in the control circuit 15 receives a signal from the position sensor-12. , It is possible to recognize the sliding position of the movable pulley 5 and detect the pulley ratio, and the actual gear ratio is calculated by inputting the signals from the rotation sensors 13 and 14. be able to. The control circuit 15 is connected to a motor drive circuit 16 which supplies a drive current to the motor 6, and the movable pulley 5 is connected to the motor drive circuit 16. The control signal for sliding the to the target position is output. When the control signal is input, the motor drive circuit 16 drives the motor 6 and slides the movable pulley 5 to the target position.

The memory of the microcomputer contained in the control circuit 15 stores a three-dimensional map showing the relationship between the throttle opening, the vehicle speed and the target ratio as shown in FIG. Therefore, in addition to the signals from the position sensor-12 and the rotation sensors-13 and 14, the control circuit 15 receives the throttle opening signal from the throttle opening sensor and the vehicle speed signal from the vehicle speed sensor. . Further, an alarm display unit 17 is connected to the control circuit 15, and when the rotation state of the motor 6 indicates an abnormality as described later, the control circuit 15 displays the abnormality on the alarm display unit 17. Let

FIG. 3 shows an electric circuit of the motor drive circuit 16. As shown in FIG. 3, the motor
6 is a field effect transistor (FET) TR1, TR2
It is driven by a transistor chopper using TR3 and TR4. That is, a field effect transistor (FET) TR
When 1 and TR4 are turned on, the motor 6 is rotated in the positive direction, while field effect transistors (FET) TR2 and T4 are turned on.
When R3 is turned on, the motor 6 is rotated in the reverse direction.
When the motor 6 is rotated in the forward direction, the movable pulley 5 is slid in the direction in which the rotational diameter of the belt 4 of the drive pulley 2 is increased, so that the driven pulley 3 is Be accelerated. on the other hand,
When the motor 6 is rotated in the reverse direction, the movable pulley 5 is slid in the direction in which the rotational diameter of the belt 4 of the drive pulley 2 is reduced, so that the driven pulley 3 is moved. Be slowed down.

The motor 6 is controlled at a variable speed by the duty control by the control circuit 15. That is, since the duty control signal from the microcomputer incorporated in the control circuit 15 is applied to the gates of the field effect transistors (FETs) TR1 and TR2 through the buffer gate, the transistors TR1 and TR1 are connected. TR2 is ON / OFF controlled according to the duty ratio. On the other hand, the control circuit 1 is connected to the gates of the field effect transistors (FET) TR3 and TR4.
Since the normal rotation or reverse rotation signal from the built-in microcomputer 5 is applied through the buffer gate,
The transistors TR3 and TR4 are turned on / off according to the forward / reverse rotation control.

Motor current detection resistors RA and RB are connected between the transistor TR3 and the ground and between the transistor TR4 and the ground, and the voltages of these resistors RA and RB must be detected. To detect the actual current of the motor 6.

FIG. 4 is a control flowchart of the motor 6 for controlling the shift of the continuously variable transmission 1 of the vehicle constructed as described above. When the microcomputer of the control circuit 15 drives and controls the motor 6 in the upshifting direction, the microcomputer determines whether the vehicle speed is a constant value and the vehicle speed is constant. When it is higher than the value, the rotation ratio is calculated based on the signals from the rotation sensors-13 and 14. When the rotation ratio is smaller than a predetermined value, that is, when the rotation ratio is higher than the predetermined value, it is determined that the state is higher, and the detection of the pulley ratio becomes impossible due to a failure of the position sensor-12 of the drive pulley-2. If
Since the transmission 1 may be shifted up to the maximum ratio and the mechanism of the transmission 1 may be damaged, the current supply to the motor 6 is stopped and the alarm display 17 displays the abnormality. .

[0017]

As described above, according to the present invention, when the target ratio of the transmission is determined and the transmission driving motor is controlled based on the target ratio, the transmission is controlled by the motor. If it becomes impossible to detect the pulley ratio due to a failure of the pulley position sensor of the drive pulley during the speed increasing process of the motor, the transmission drive pulley When it is recognized that the rotation ratio between the rotation of the motor and the rotation of the driven pulley has become smaller than a certain value, the current supply to the motor is stopped,
Since the abnormality is displayed, it is possible to prevent mechanical damage to the transmission.

[Brief description of drawings]

FIG. 1 is a three-dimensional map diagram showing a stepwise relationship between a throttle opening, a vehicle speed, and a target ratio.

FIG. 2 is an explanatory diagram of a control configuration of a continuously variable transmission of a vehicle.

FIG. 3 is an electric circuit diagram of a chopper.

FIG. 4 is a motor control flow chart.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 transmission 2 drive pulley 3 driven pulley 4 belt 5 movable pulley 6 motor 9 gear 11 slider 12 position sensor 13 rotation sensor 14 rotation sensor 15 control circuit 16 mode -Ter drive circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sadao Yamada 7-22 Minamiichibancho, Atsuta-ku, Nagoya Aichi Kikai Kogyo Co., Ltd.

Claims (1)

[Claims] 1. A gear shift for determining a target ratio of a transmission, driving a motor for driving the transmission based on the target ratio, and controlling the pulley of the transmission so as to attain the target ratio. In the control method, when it is determined that the rotation ratio between the rotation of the drive pulley of the transmission and the rotation of the driven pulley of the transmission is smaller than a certain value in the process of increasing the speed of the motor, the motor is controlled. The method for controlling gear shift is characterized by stopping the supply of drive current to the vehicle and displaying an abnormality.