JPS6237548A - Automatic transmission - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

[Field of Industrial Application] The present invention relates to automatic transmissions, and in particular calculates an appropriate gear position by a calculation means, and automatically adjusts the gear position by an actuator when the IJ value obtained by this calculation is different from the current gear position. Concerning automatic transmissions that are designed to change position. KSummary of the Invention The present invention provides an automatic transmission in which the gear position is automatically changed by an actuator so that the gear position is the optimum gear position obtained by a calculation means.
If slippage of the drive wheels is detected and the slip value of the drive wheels exceeds a predetermined value, the automatic gear shifting operation described above is prohibited and This prevents the transmission from automatically shifting up when the drive wheels slip on the road surface, and prevents the vehicle from being unable to start on snowy roads, etc.

[Conventional technology]

Automatic transmissions combined with automatic clutches have been proposed. This automatic transmission is equipped with an actuator that automatically performs gear shifting operations, and a microcomputer calculates the optimal transmission gear A7 position from the vehicle speed and the accelerator stroke. The gear shifting operation is performed by the actuator so that the gear shift operation is performed by the actuator. At this time, the clutch is automatically disengaged by the actuator. Therefore, with such an automatic transmission, the driver is freed from complicated gear shifting operations. [Problems to be solved by invention K] However, in such automatic transmissions, the micro combicoater detects the vehicle speed, and when the vehicle speed reaches an upper limit, the transmission is automatically shifted up accordingly. . Therefore, if the tie A7 slips on a road surface with a low coefficient of friction such as a snowy road, the vehicle speed will be detected from this slipped rotational speed, even though the vehicle speed has not actually reached the specified speed. When the tires slip, the transmission automatically shifts up. Therefore, when driving on such snowy roads, the torque transmitted to the drive wheels becomes smaller due to upshifting, and the problem arises that the vehicle will eventually become unable to start. If the drive wheels slip when starting on such snowy roads, you can switch the operation to manual mode and change gears, but this operation is not only troublesome, but also The advantage of the transmission is reduced by 1.Furthermore, in the case of a driver who is not familiar with manual operation of an automatic transmission, the vehicle will not be able to start in such a situation.The present invention is as follows. This was done in view of the above problems, and when the drive wheels of a vehicle equipped with an automatic transmission slip, the transmission is prohibited from shifting up, thereby preventing the vehicle from being able to start. It is an object of the present invention to provide an automatic transmission that prevents the above problems. Means for solving the problem Σ As shown in FIG. In addition, in a transmission in which the gear position is automatically changed by an actuator when the value obtained by this calculation is different from the current gear position, there is provided a means for detecting the slip of the drive wheel, and a means for detecting the slip of the drive wheel. A means for determining whether the slip value exceeds a predetermined value is provided, and a means for prohibiting a gear shifting operation when the determining means determines that the slip value exceeds a predetermined value. Therefore, according to the present invention, if the driving wheels do not slip and the slip value of the driving wheels exceeds a predetermined value, the gear shifting operation is prohibited. Therefore, if the drive wheels slip on a road surface with a low coefficient of friction, such as a snowy road, the transmission's gear shifting operation is prohibited, which prevents automatic upshifting. Embodiment K] The present invention will be explained below with reference to an embodiment shown in the drawings. Fig. 2 shows an embodiment of the present invention in combination with an automatic transmission according to an embodiment of the present invention. This figure shows an automobile engine used, and this engine is composed of, for example, a diesel engine 10 for a truck.A fuel injection pump 11 is provided on the side of the engine 10. The fuel injection pump 11 is configured to sequentially inject and supply fuel to each cylinder.Furthermore, this fuel injection pump 11 is driven by the engine 10 via a timer 12, and the timing of injection is adjusted by the timer 12. There is. The fuel injection pump 11 also includes an actuator 13, which moves a control rack to control the amount of fuel supplied. And the actuator 13 is the microcomputer 1
It is controlled by 4. In addition, the detection outputs of a rotation sensor 15 that detects the rotation of the engine 10 and a rack position sensor 16 that detects the rack position of the fuel injection pump 11 are input to the micro combination coke 14, respectively. . A flywheel housing 17 is provided on the rear side of the engine 10, and a transmission 18 is arranged on the rear side of the housing 17. The clutch on the rear side of the flywheel disposed within the flywheel housing 17 is controlled to engage and disengage by a clutch actuator 19. The transmission 18 also includes a shift actuator 20 and a select actuator 21 for selecting the gear position. Additionally, a vehicle speed sensor 22 detects the rotation speed on the output side of this transmission 1B.
The transmission 18 is provided with a gear position sensor 25 for detecting the gear position of the transmission 18, and the outputs of these sensors 22, 25 are input to the microcomputer 14. Further, an accelerator stroke sensor 2/I for detecting the depression of the accelerator pedal 23 is connected to the microcomputer 14. Next, the automatic speed change operation of the transmission 18 combined with the engine 10 having the above configuration will be explained based on the flowchart shown in FIG. The microcomputer 14 reads the stroke of the accelerator pedal 23 or the load of the engine 10 using an accelerator stroke sensor 24. Further, the vehicle speed is read from the rotational speed on the output side of the transmission 18 by the vehicle speed sensor 22. Then, the detection output of the vehicle speed sensor 22 is differentiated to calculate the rate of change in vehicle speed. Calculation of the rate of change in vehicle speed is used to detect whether the driving wheels are slipping.In addition to determining whether the rate of change is below a certain value, it is also necessary to calculate whether the driving wheels are slipping. Therefore, if the rate of change is greater than a predetermined value, no gear shifting operation is performed. In other words, in the case of starting, if 13.
The transmission 18 is prevented from performing an upshift operation. On the other hand, if the drive wheels are not slipping and the rate of change in vehicle speed is below a certain level, the microcomputer 14 uses the gear position sensor 25 of the transmission 18 to read the gear position. Further, the transmission 18 reads a shift map of the transmission 18 from its storage means, for example, a ROM. The optimal gear position of the transmission 18 is then calculated with reference to this map. This optimum gear position is then compared with the current gear position, and if the two match, no gear change operation is performed and the transmission 18 is maintained in its current state. On the other hand, if the current gear position and the appropriate gear position do not match, a gear shifting operation is performed. This speed change operation is performed as follows. First, the microcomputer 14 once disengages the clutch in the flywheel housing 17 using the clutch actuator 19. In this state, the microcomputer 74 uses the shift actuator 20 and the selection actuator 21 to perform a speed change operation so that the gears of the transmission 18 are at optimal gear positions. If a new gear is selected, the microcomputer 14 again uses the clutch actuator 19 to connect the clutch. This completes the series of shift 01 operations, and the transmission 18 is automatically switched to an appropriate gear position. In this way, in the automatic transmission according to this embodiment, the microcomputer 14 differentiates the vehicle speed value obtained by the vehicle speed sensor 22 to determine the rate of change in the vehicle speed, and if the value of the rate of change is greater than or equal to a certain one shift, If it is determined that the drive wheels are slipping, the automatic speed change operation of the transmission 18 is prohibited. Therefore, when the tires of the driving wheels slip on a road surface with a low coefficient of friction such as a snowy road, it is possible to avoid a situation where the transmission 18 does not shift up and the vehicle cannot start. Therefore, when the tires slip in this way, there is no need for the driver to manually shift the transmission 18, making the operation easier. In addition, even a driver who does not know how to use manual operation will be able to start the vehicle on a snowy road. [Effects of the Invention] As described above, the present invention includes a means for detecting slip of a driving wheel, a means for determining whether or not the value of slip of the driving wheel exceeds a predetermined value, and a means for detecting slip of the driving wheel by means of this determining means. In this embodiment, there is provided a means for prohibiting the gear shifting operation when it is determined that the value of . Therefore, according to the present invention, when the drive wheels slip, the gear shifting operation is prohibited by the prohibition means, and when the drive wheels slip on a road surface with a low coefficient of friction such as a snowy road, the transmission shift operation is prohibited. This will prevent the upward movement. Therefore, it is possible to prevent the vehicle from being unable to start on snowy roads or the like.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an automatic transmission showing the gist of the present invention, FIG. 2 is a side view of an engine equipped with this automatic transmission, and FIG. 3 is a flow chart showing the operation of this automatic transmission. In the symbols used in the drawings, 14...Microcomputer 17...Flywheel housing 18...Transmission 19...Clarachi actuator 20...Shift acticoator 21...Select 1~ actuator 22 ...Vehicle speed sensor 24...Accelerator stroke sensor 25...Gear position sensor.

Claims (1)

[Claims] In a transmission in which an appropriate gear position is calculated by a calculating means, and the gear position is automatically changed by an actuator when the value obtained by this calculation is different from the current gear position. , means for detecting the slip of the drive wheel, and means for determining whether the value of the slip of the drive wheel exceeds a predetermined value;
An automatic transmission characterized in that it is provided with means for prohibiting a gear shifting operation when the determination means determines that the slip value exceeds a predetermined value.