JPH0481066B2 - - Google Patents

Abstract

PURPOSE:To allow a drive feeling at a time of cornering and others to be improved by arranging a detecting means to determine that the difference in revolution between a right and a left driving wheels exceeds the started value, so as to restrain a change-speed operation from being effected when the difference is found to exceed the stated value. CONSTITUTION:When a shift lever 23 is in an auto-position of an automatic transmission, a computer 21 allows the required gear ratio to computed based on the output signal from both an acceleration sensor 25 and a speed sensor 26 permitting actuators 17 and 18 for the shift selection to be controlled based on the computed result. This allows the gear of the transmission 15 to be automatically selected. In this case, the number of revolution of the right and left driving wheels 31 and 32 is detected by each of respective revolution sensors 34 and 35, and it is determined to see if the difference in revolution exceeds the stated value. And if the difference is found to exceed the stated value, a change-speed signal is allowed to be cancelled. This configuration restrains a change-gear operation at a time of cornering and others from being effected enabling an improved drive feeling to be maintained.

Description

[Detailed Description of the Invention] 〓Field of Industrial Application〓 The present invention relates to an automatic transmission that can automatically change the gear ratio, and particularly relates to an automatic transmission that can change the gear ratio automatically.
The present invention relates to an automatic transmission in which a calculation means selects a gear to be used in accordance with an accelerator opening degree, etc., and an actuator engages the selected gear to obtain a predetermined gear ratio.

〓Prior Art〓 In order to utilize the rotational torque of an automobile engine most efficiently, a transmission has conventionally been attached to the engine. This transmission selects the gear to be used according to the driver's gear change operation, and changes the engine speed to an appropriate value and transmits it to the drive wheels. . However, with such conventional transmissions, the driver has to operate the gear shift lever depending on the driving condition of the vehicle, which makes driving operations extremely complicated.

To overcome these drawbacks, automatic transmissions have been proposed. In this automatic transmission, a calculation means such as a microcomputer selects the most suitable gear according to vehicle speed, accelerator opening, etc., and an actuator meshes the selected gears to automatically set a predetermined gear ratio. It was designed to obtain By equipping automobiles with such automatic transmissions,
The driver hardly needs to operate a lever to change gears.

However, with such automatic transmissions, gear shifting operations are performed automatically according to vehicle speed and accelerator opening, so gear shifting operations are difficult to perform even when turning, for example, where conventionally the driver did not consciously shift gears. It will be done. If a variable movement is performed during a turn, a problem occurs in which the engine brake temporarily becomes ineffective.

〓Object of the Invention〓 The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an automatic transmission that prevents automatic gear shift operation when a vehicle turns. It is something.

〓Structure of the Invention〓 According to the present invention, a calculation means selects a gear to be used according to vehicle speed and accelerator opening, and an actuator meshes the selected gear to obtain a predetermined gear ratio. In an automatic transmission that is equipped with The gear shift operation is prohibited when the difference between the rotational speeds of the left and right drive wheels is greater than or equal to a predetermined value.

〓Example〓 The present invention will be described below with reference to an illustrated example.
FIG. 1 shows an engine for a motor vehicle equipped with an automatic transmission according to an embodiment of the present invention, and this engine is composed of a diesel engine 10 for a truck. The diesel engine 10 is equipped with a fuel injection pump 11, which sequentially supplies fuel to each cylinder of the engine 10.
The fuel injection pump 11 is driven by the engine 10 via a timer 12, and the timing of fuel injection is adjusted by the timer 12. Furthermore, the fuel injection pump 11 is equipped with a mechanical governor 13, and the governor 13 is adapted to adjust the amount of fuel to be injected.

A flywheel housing 14 is provided on the rear side of the engine 10, and this housing 1
A flywheel fixed to the end of the crankshaft is housed within the crankshaft. A clutch (not shown) is provided on the back side of the flywheel, and a transmission 15 is attached to the back side of the flywheel housing 14 so as to be connected to this clutch. This transmission 15 is configured to change the rotational speed of the engine 10 to an appropriate value and transmit it to the drive wheels via a propeller shaft 16.

The transmission 15 constitutes an automatic transmission, and a shift actuator 17 and a selection actuator 18 are provided above the transmission. Furthermore, a clutch actuator 19 is mounted on the outer surface of the casing of the transmission 15 for controlling the connection and disconnection of a clutch mounted on the rear side of the flywheel. Furthermore, a fuel control actuator 20 is provided at the front end of the fuel injection pump 11 to adjust the position of a control latch and control the amount of fuel supplied. These four actuators 17, 18,
19 and 20 are adapted to be driven based on instructions from the microcomputer 21 via respective driving means.

The input side of the microcomputer 21 is connected to a control box 22. This control box 22 is the gear shift lever 2.
It has 3. Furthermore, this microcomputer 21 is connected to an accelerator sensor 25 that detects the opening degree of the accelerator or the amount of depression of the accelerator pedal 24. Further, the microcomputer 21 is connected to a vehicle speed sensor 26, an engine rotation sensor 27, a rack sensor 28, and a clutch sensor 29, respectively.

The vehicle speed sensor 26 is provided on the side of the transmission 15.
The vehicle speed is detected based on the rotational speed on the output side of the engine. Further, the engine rotation sensor 27 is attached to the front side of the engine 10 and is adapted to detect the rotation speed of the engine 10. Furthermore, the rack sensor 28 is connected to the actuator 20.
It is attached to the tip side of the fuel injection pump 1.
The position of the control rack No. 1 is detected. Further, a clutch sensor 29 is attached to the tip side of the clutch actuator 19, and is adapted to detect the state of engagement and disconnection of the clutch.

Furthermore, a microcomputer 21 constituting the calculation means of the automatic transmission according to this embodiment
The input side of is connected to two rotation sensors 34 and 35, respectively. These rotation sensors 34,
35, as shown in FIG. 2, left and right drive wheels 31,
32, respectively, and the rotational speed of these drive wheels 31, 32 is detected. Note that these drive wheels 31 and 32 are connected to a transmission 15 via a propeller shaft 16 and a differential gear 33.
It is designed to be driven by the torque on the output side of.

Next, the operation of this automatic transmission configured as described above will be explained. This operation is performed based on a program preset in the microcomputer 21.
When the shift lever 23 of the control box 22 is in the automatic position, the shift operation is automatically performed. On the other hand, when the shift lever 23 is in the manual position, the manually selected shift operation is performed by the actuator 1.
7 and 18.

To give an overview of the automatic shift operation, the microcomputer 21 detects whether the shift lever 23 of the control box 22 is in the automatic position, and if it is in the automatic position, the accelerator pedal 24 is depressed at regular intervals. The accelerator sensor 2 detects the amount or accelerator opening degree and the vehicle speed.
5 and the vehicle speed sensor 26. Further, the microcomputer 21 reads the map stored in its memory, and based on this map, calculates whether automatic gear shifting is possible. If automatic gear shifting is possible, gear shifting is performed to obtain the calculated gear ratio. On the other hand, if it is determined that automatic gear shifting is not possible, gear shifting is not performed.

The specific operation of automatic gear shifting is such that the shift actuator 17 and the selection actuator 18 are operated based on a command from the microcomputer 21 via a drive means (not shown), and the gears of the transmission 15 are selected. The selected gears of the transmission 15 are thereby brought into mesh. Therefore, a predetermined gear ratio can be obtained in this way. During this shift operation, the actuator 19 temporarily switches the clutch to the disengaged state, and then returns the clutch to the connected state in synchronization with the end of the shift operation.

Further, according to the automatic transmission according to this embodiment, the automatic gear shifting operation of the transmission 15 is prohibited when the vehicle is turning. This operation will be explained based on the flowchart shown in FIG.
1 reads the rotation speeds of the left and right drive wheels 31 and 32 based on the detection outputs of the left and right rotation sensors 34 and 35, respectively. Next, the microcomputer 21 calculates the difference in rotational speed between the left and right drive wheels 31 and 32. Then, it is determined whether the difference in rotation speed is above a certain value, and only if it is below a certain value, a shift operation signal is generated, and if the difference in rotation speed is above a certain value, the shift signal is canceled. The gear shifting operation is prohibited.

When the vehicle turns, the differential gear system 33 creates a difference in the rotational speed of the left and right drive wheels 31, 32, so the above operation allows the speed change when the vehicle turns. The operation will be prohibited. Therefore, a gear change operation is performed while turning,
It becomes possible to prevent the engine brake control from being temporarily released. Therefore, it is possible to improve the driving feeling during cornering. Furthermore, the above-mentioned operation prevents a shift operation when one of the drive wheels is idling, so it is also possible to prevent a shift operation during a slip.

〓Effects of the Invention〓 As described above, according to the present invention, the shift operation is prohibited when the difference in the rotational speed between the left and right drive wheels is equal to or greater than a predetermined value. Therefore, with such a configuration, the gear change operation is prohibited when turning, and the gear change operation is also prevented when the drive wheels slip.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an automatic transmission according to an embodiment of the present invention, Fig. 2 is a plan view of main parts showing the installation of a rotation sensor of a drive wheel, and Fig. 3 is a gear shift operation of this transmission. This is a flowchart for the ban. The names of the main parts in the drawing are as follows.
15... Transmission, 17... Shift actuator, 18... Select actuator, 19... Clutch actuator, 21...
... Microcomputer, 25 ... Accelerator sensor, 26 ... Vehicle speed sensor, 31 ... Drive wheel (left),
32... Drive wheel (right), 34... Rotation sensor (left), 35... Rotation sensor (right).

Claims (1)

[Claims] 1. A calculation means selects a gear to be used according to vehicle speed and accelerator opening, and an actuator meshes the selected gear to obtain a predetermined gear ratio. In an automatic transmission, means for detecting a difference in rotational speed between left and right driving wheels, and means for prohibiting a gear shifting operation of the transmission when the difference in rotational speed between left and right driving wheels is greater than or equal to a predetermined value. An automatic transmission characterized in that it is provided with the following.