JPS6237558A - Automatic transmission - Google Patents

Abstract

PURPOSE:To make accelerability ever so better, by reducing the number of shift motions by jumping one shift-down line of the upper step side at a time when the number of the shift down line of a shift map to be crossed is more than two in case of supposing that an accelerator pedal is pressed down to the specified extent. CONSTITUTION:When an accelerator pedal 24 is operated, a microcomputer 21 refers to a shift map and simultaneously when judging to go beyond more than two shift-down lines, it jumps a shift-down line at the upper step side, performing a shift-down line alone at a lowermost step. Therefore, the shift motion frequency of unnecessary shift-down is reduced so that a torque interruption time is shortened, thus speedy acceleration takes place.

Description

[Detailed description of the invention]

[Field of Industrial Application] The present invention relates to an automatic transmission, and in particular to a self-help system that calculates an appropriate gear position and automatically changes the gear position using an actuator to the value obtained by this calculation. Regarding transmission.

[Summary of the invention]

The present invention, in an automatic transmission that automatically shifts gears to the appropriate gear position, determines the downshift line on the shift map that intersects when the accelerator pedal is depressed by a predetermined amount. At the same time, when it is determined that there are two or more intersecting downshift lines, at least one shift down line on the upper gear side is jumped and a gear shift operation is suddenly performed to a lower gear position. The system is designed to reduce the number of times the vehicle shifts, and to omit unnecessary downshift operations during acceleration. K. PRIOR ART Automatic transmissions have been proposed in order to omit the driver's complicated operations for shifting gears. In this automatic transmission, a calculation means such as a microcomputer selects the gears to be used depending on the vehicle speed, accelerator opening degree, etc., and an actuator meshes the selected gears to automatically obtain a predetermined gear ratio. This is what I did. By equipping a vehicle with such an automatic transmission, the driver hardly needs to operate a lever to change gears. [Problems to be solved by invention K] In such an automatic transmission, even if the vehicle speed decreases while the accelerator pedal is released, it does not immediately downshift.
This prevents unnecessary engine braking from being applied. Therefore, when the accelerator pedal is depressed for re-acceleration while the transmission is in the upper gear position, the operating locus will cross multiple downshift lines as shown in FIG. Since automatic transmissions perform gear shifting operations while referring to the upshift and downshift lines on the shift map, in this case, the automatic transmission first shifts from 5th gear to 4th gear, and then from 4th gear to 3rd gear. , two gear shifts will be performed. When the gears are changed twice like this in a short period of time,
Because the torque is interrupted each time, it is difficult to accelerate. Therefore, not only the driving feeling deteriorates, but also the acceleration performance deteriorates. The present invention has been made in view of such problems, and when the operation locus intersects with a plurality of downshift lines, the downshift line on the lower gear side is jumped, thereby changing the gear shifting operation. The purpose of the present invention is to provide an automatic transmission that reduces the number of times the vehicle is operated, improves driving feeling, and improves acceleration performance. Means for Solving Problem K] As shown in FIG. 1, the present invention calculates an appropriate gear position and automatically adjusts the gear position using an actuator so that the value obtained by this calculation is achieved. In a transmission to be changed, means for determining the number of downshift lines of a shift map that intersect when the accelerator pedal is depressed by a predetermined amount, and when the number of downshift lines that intersect is two or more. A means for jumping at least one downshift line on the lower gear side to reduce the number of gear shifting operations is provided. [1] According to the present invention, when the accelerator pedal is depressed for re-acceleration while the transmission is in the upper gear position, the shift caused by intersecting the downshift line on the lower gear side Down operation is omitted,
The gear will suddenly be shifted to the lower gear position,
It becomes possible to prevent wasteful gear shifting operations and reduce the number of them. Therefore, the driving feeling is improved, and the torque interruption time is shortened, making it possible to accelerate quickly. K Embodiment The present invention will be described below with reference to an illustrated embodiment. FIG. 2 shows an automobile engine 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 connected to the engine 10 via the timer 12.
Moreover, the timing of fuel injection is adjusted by this timer 12. Roughly speaking, 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. The flywheel housing 1 is located on the back side of the engine 10.
4 is provided, and a flywheel fixed to the end of the crankshaft is accommodated within this housing 14. 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 has an engine 10
Shift the rotation speed of the propeller shirts 1 to 16 to a specified value.
The signal is transmitted to the drive wheels via the The transmission 15 constitutes an automatic transmission, and a shift actuator 17 and a selection actuator 18 are provided above the transmission. Further, a clutch actuator 19 is mounted on the outer surface of the casing of the transmission 15 for controlling connection and disconnection of a clutch mounted on the back side of the flywheel. Furthermore, a fuel control actuator 20 is provided on the front end side of the fuel injection pump 11 to adjust the position of the control rack and control the supply of fuel. These four actuators 17, 18, 19, and 20 are each driven based on instructions from the microcomputer 21 via driving means. The input side of the microcomputer 21 is connected to a control box 22 . This control box 22 is equipped with a gear shift lever 23. Furthermore, this microcomputer 21 is connected to an accelerator sensor 25 that detects the opening degree of the accelerator or the maximum depression of the accelerator pedal 24. Further, the microcomputer 21 is connected to a heavy 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 surface of the transmission 15 and detects the vehicle speed based on the rotational speed of the output side of the transmission 15. Further, the engine rotation sensor 27 is attached to the front side of the engine 10 and is configured to detect the rotation speed of the engine 10. Moreover, the rack sensor 28 is attached to the tip side of the actuator 20, and the rack sensor 28 is attached to the tip side of the actuator 20.
The position of the control rack No. 1 is detected. Further, the clutch sensor 29 is attached to the tip side of one of the clutch actuators, and is adapted to detect the connected and disconnected states of the clutch. 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, and when the shift lever 23 of the control box 22 is in the automatic position, the shift operation is automatically performed. There is. On the other hand, when the gear shift lever 23 is in the manual position, the manually selected gear shift operation is performed by the actuator 17.1.
This is done via B. To give an overview of the operation of automatic gear shifting, the microcomputer 21 detects whether the gear 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 opening degree and vehicle speed are read from the accelerator sensor 25 and the vehicle speed sensor 26, respectively. Furthermore, the microcomputer 21 reads the map stored in its memory, and based on this map,
Performs calculations to determine 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 performed by the microcomputer 21.
Based on the command, the shift actuator 17 and the selection actuator 18 are activated via a drive means (not shown).
is operated to select a gear of the transmission 15, thereby achieving meshing of the selected gear of the transmission 15. Therefore, a predetermined gear ratio can be obtained in this way. During this shift operation, the actuator 19 switches the clutch to the disconnected state, and at the same time synchronizes with the end of the shift operation, the clutch is brought into the connected state again. Further, in the automatic transmission according to this embodiment, when the accelerator pedal 24 is depressed for re-acceleration in the upper gear, unnecessary gear shifting operations are omitted. This operation will be explained based on the flowchart shown in FIG. The microcomputer 21 reads the depression period of the accelerator pedal 24 using the accelerator sensor 25, and also determines whether the accelerator pedal 24 is in the released state. If the accelerator pedal 24 has been released, the output of the accelerator sensor 25 is further increased to W, and it is determined whether the accelerator pedal 24 has been depressed for re-acceleration. Therefore, from this,
If the accelerator pedal 24 is depressed with the intention of re-accelerating, this can be detected. When the accelerator pedal 24 is depressed, the microcomputer 21 refers to the shift map, and if the accelerator pedal 24 is depressed by more than 80%, for example, as shown in FIG. 4, the microcomputer 21 crosses two or more downshift lines. Make a judgment as to whether or not. If it is determined that two or more downshift lines are to be crossed, the shift down line on the upper side is jumped, and only the lower shift down line is performed again. For example, as shown in Figure 4, if the downshift line from 5th gear to 4th gear intersects with the downshift line from 4th gear to 3rd gear, the downshift operation to 4th gear will be performed. Skip this and suddenly shift down from 5th gear to 3rd gear. Therefore, in this case, the operation of downshifting from 5th gear to 4th gear is omitted, and the number of gear changes is reduced by one. Assuming that the accelerator pedal 24 is depressed by 80% or more, if only one downshift line is crossed, a normal downshift operation is performed. According to the automatic transmission according to this embodiment, when the accelerator pedal 24 is released, no downshift is performed even if the vehicle speed decreases, thereby preventing unnecessary engine braking. If the transmission 15 is in the upper gear position and the accelerator pedal 24 is depressed for re-acceleration just before the vehicle is about to stop, the operating locus will intersect with two or more downshift lines, so each time A gear shifting operation is performed every time, and this often results in torque interruption. However, according to the automatic transmission according to the present embodiment, as described above, the shift map is referred to when the accelerator pedal 24 is depressed by a certain amount or more, for example, 80% or more, and the downshift line on the upper side is jumped. In this way, the gear shifting operation is omitted, thereby shortening the torque interruption time and allowing prompt acceleration. Furthermore, since the number of gear changes is reduced, the driving feeling is improved.

【Effect of the invention】

As described above, the present invention determines the number of intersecting downshift lines of the shift map when the accelerator pedal is depressed by a predetermined amount, and when the number of intersecting downshift lines is two or more, at least One downshift line on the upper side is jumped to reduce the number of gear shifting operations. Therefore, according to the present invention, the number of unnecessary downshifts is reduced, driving feeling is improved, and the torque interruption time is shortened, making it possible to accelerate quickly. It becomes possible.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the gist of the present invention, FIG. 2 is a block diagram of an automatic transmission according to an embodiment of the present invention, FIG. 3 is a flowchart for omitting the speed change operation of this automatic transmission, and FIG. The figure is a graph for this operation, and FIG. 5 is a graph showing the downshift operation of a conventional automatic toss-run mission. In the symbols used in the drawings, 15...Transmission 17...Shift actuator 18...Select actuator 21...Microcomputer 24...Accelerator pedal 25...Accelerator sensor 26...Vehicle speed It is a sensor.

Claims (1)

[Claims] In a transmission that calculates the appropriate gear position and automatically changes the gear position using an actuator to reach the value obtained by this calculation, it is assumed that the accelerator pedal is depressed by a predetermined amount. A means for determining the number of shift down lines of a shift map that intersect in the case of a shift map, and a means for determining the number of shift down lines in a shift map that intersect when An automatic transmission characterized by being provided with means for reducing the number of times.