JPH0624897B2 - Automatic transmission - Google Patents

Description

The present invention relates to an automatic transmission, and particularly to calculating a proper gear position, and automatically shifting the gear position by an actuator so as to obtain a value obtained by this calculation. Regarding the automatic transmission that has been changed.

[Outline of Invention]

The present invention, in an automatic transmission that automatically shifts gears to an appropriate gear position, when the clutch is engaged after the shift operation is completed, the engine speed and the clutch The engine speed is controlled so that they are almost equal to each other, and after the half-clutch start point, the means for controlling the amount of fuel supplied to the engine is gradually changed to the increasing side. The torque fluctuation when the clutch is engaged is suppressed to reduce the shock feeling.

[Conventional technology]

Automatic transmissions have been proposed in order to avoid the driver's cumbersome shifting operations. This automatic transmission selects a gear used by a computing means such as a microcomputer according to a vehicle speed, an accelerator opening, etc., and meshes the gear selected by an actuator to automatically obtain a predetermined gear ratio. It was done. By equipping an automobile with such an automatic transmission, the lever operation for the driver to shift gears becomes almost unnecessary.

[Problems to be solved by the invention]

When shifting is performed by such an automatic transmission, the clutch is disengaged by the actuator, and the clutch is re-engaged when the shifting operation is completed. If there is a difference between the number of revolutions of the engine and the number of revolutions of the clutch when the clutch is engaged after shifting, a shock is generated due to the difference in the number of revolutions. Therefore, both were set to the same rotation speed. However, even if such a rotation speed control is performed, there is a problem that the torque is changed by connecting the clutch, and in some cases, the engine brake is activated immediately after the clutch is engaged. Therefore, according to the conventional automatic transmission, there is a problem in that the torque is varied due to the engagement of the clutch after the gear shift to give a shock.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide an automatic transmission that suppresses fluctuations in torque at the time of ending automatic gear shifting and engaging a clutch to reduce shock. It is intended.

[Means for solving problems]

The present invention calculates an appropriate gear position and automatically changes the gear position by an actuator so as to obtain the value obtained by this calculation. An automatic transmission that disengages and re-engages the clutch by the clutch actuator when the gear position is changed.When the clutch is engaged after the shifting operation is completed, the transmission is connected to the starting point of the half-clutch. Means to control the diesel engine speed so that the diesel engine speed and the clutch speed are almost equal to each other, and determine whether the half-clutch range is entered during the clutch engagement operation. And the means for determining When it is detected that the clutch has entered the region of the clutch, means for forcibly gradually moving the control rack of the fuel injection pump that supplies fuel to the diesel engine to the increasing side, and the moving position of the control rack is the accelerator pedal. The present invention relates to an automatic transmission including means for canceling the forced movement of the control rack when a position corresponding to a stepping amount is reached.

[Action]

Therefore, the shift operation is changed by the actuator such that the clutch is temporarily disengaged by the clutch actuator and the gear position of the transmission becomes the value obtained by the calculation. After that, the clutch is connected again.

When the clutch is engaged after the shift operation is completed, the control means controls the diesel engine speed so that the rotational speed of the diesel engine connected to this transmission and the rotational speed of the clutch are substantially equal to each other until the starting point of the half-clutch. The rotation speed is controlled. When the judging means detects that the half-clutch area has been entered,
The control rack of the fuel injection pump that supplies fuel to the diesel engine is forcibly moved to the increasing side by the moving means. This movement operation is performed until the movement position of the control rack reaches the position corresponding to the depression amount of the accelerator pedal, and the above-mentioned forced movement is released at that position.

〔Example〕

The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 2 shows an engine of an automobile equipped with an automatic transmission according to an embodiment of the present invention, which is composed of a diesel engine 10 for a truck. The diesel engine 10 is equipped with a fuel injection pump 11, and the engine 11 is driven by the pump 11.
Fuel is sequentially supplied to each of the cylinders.
The fuel injection pump 11 is connected to the engine 10 via the timer 12.
The timer 12 adjusts the timing of fuel injection. Further, the fuel injection pump 11 is provided with a mechanical governor 13, and the governor 13 adjusts the fuel injection amount.

The flywheel housing 1 is on the rear side of the engine 10.
4 is provided, and a flywheel fixed to the end of the crankshaft is housed in the housing 14. A clutch 30 is provided on the rear side of the flywheel, and a transmission 15 is mounted on the rear side of the flywheel housing 14 so as to be connected to the clutch 30. This transmission 15 is the engine 1
The speed is changed to a predetermined value of 0 rpm, and the propeller shaft 16
It is adapted to be transmitted to the drive wheels via.

The transmission 15 constitutes an automatic transmission, and a shift actuator 17 and a select actuator 18 are provided on the upper portion thereof. Further, the clutch actuator 19 for controlling connection and disconnection of the clutch 30 mounted on the rear side of the flywheel is provided by the transmission 1
5 is mounted on the outer surface of the casing. Further, on the front end side of the fuel injection pump 11, there is provided a fuel control actuator 20 for adjusting the position of the control rack to control the fuel supply amount. These 4
The two actuators 17, 18, 19, and 20 are driven based on instructions from the microcomputer 21 via driving means.

The input side of the microcomputer 21 is connected to the control box 22. The control box 22 has a speed change lever 23. Further, the microcomputer 21 is connected to an accelerator sensor 25 that detects the accelerator opening or the depression amount 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 surface of the transmission 15 and detects the vehicle speed by the number of rotations on the output side of the transmission 15. The engine rotation sensor 27 is attached to the front side of the engine 10 and detects the rotation speed of the engine 10. Further, the rack sensor 28 is attached to the tip end side of the actuator 20, and the fuel injection pump 11
It is designed to detect the position of the control rack. The clutch sensor 29 is attached to the tip end side of the clutch actuator 19, and the clutch 30
It is designed to detect the connection and disconnection status of the.

Next, the operation of the automatic transmission having the above structure will be described. This operation is performed based on a program preset in the microcomputer 21, and when the position of the speed change lever 23 of the control box 22 is the automatic position, the speed change operation is automatically performed. There is. On the other hand, when the shift lever 23 is at the manual position, the manually selected shift operation is performed by the actuators 17, 1
8 is performed.

The outline of the automatic shift operation will be described. The microcomputer 21 detects whether or not the position of the shift lever 23 of the control box 22 is the automatic position, and in the case of the automatic position, the accelerator pedal 24 is depressed at a constant cycle. The amount or the accelerator opening and the vehicle speed are read from the accelerator sensor 25 and the vehicle speed sensor 26, respectively. Further, the mylo computer 21 reads the map stored in the memory and, based on this map, calculates whether or not automatic shifting is possible. If automatic gear shifting is possible, the gear shifting operation is performed so as to obtain the calculated gear ratio. On the other hand, when it is determined that the automatic shift is impossible, the shift operation is not performed.

The specific operation of automatic shifting is performed by the microcomputer 21.
On the basis of the command from the above, via a drive means (not shown), the shift actuator 17 and the select actuator 18
Is operated so that the gears of the transmission 15 are selected, so that the meshing of the selected gears of the transmission 15 is achieved. Therefore, a predetermined gear ratio can be obtained in this way. During this gear shifting operation, the actuator 19 switches the clutch 30 to the disengaged state, and the clutch 30 is brought into the engaged state again in synchronization with the end of the gear shifting operation.

When the clutch is engaged by performing the above-mentioned automatic shift, control based on the flow chart shown in FIG. 3 is performed in order to reduce shock due to torque fluctuation. That is, the microcomputer 21 determines whether or not the clutch 30 connection signal is present, and when the clutch 30 connection signal is present, controls the engine speed of the engine 10 so as to be equal to the clutch 30 speed. , And the clutch 30 in this state
The connection is started, and the stroke is read by the clutch sensor 29 to determine whether or not the half-clutch region has been entered. When the clutch 30 enters the half-clutch region, the microcomputer 21 causes the actuator 20 to gradually return the control rack of the fuel injection pump 11 to the position corresponding to the depression amount of the accelerator pedal 24. Clutch 3 at the same time
The connection of 0 is continued, and the actuator 19 is operated until the clutch 30 is completely connected.

As described above, in the automatic transmission according to the present embodiment, as shown in FIG. 4C, the rotation speed of the engine 10 is set to be equal to the rotation speed of the clutch 30 until the clutch 30 reaches the half-clutch region. After that, in the area of the half-clutch, the control rack is returned by the actuator 20 to a rack position corresponding to the depression amount of the accelerator pedal 24 at a substantially constant gradient as shown in FIG. 4A. ing. Since the amount of fuel supplied by the fuel injection pump 11 is increased in the half-clutch state as described above, the rotation speed of the engine 10 does not drop when the clutch 30 is completely connected, and , The transmission torque does not shift to the negative side. Therefore, it is possible to prevent the engine brake from being applied immediately after the clutch 30 is engaged to cause torque fluctuations or a shock.

The dotted line characteristics shown in FIGS. 4B, 4C and 4D are characteristics of a conventional automatic transmission that does not control the increase of fuel in the half-clutch state. In this case, when the clutch is connected after shifting, the engine and the clutch are controlled to rotate in the same way,
Although the shock due to the difference in rotational speed is reduced, torque fluctuation occurs as shown by the dotted line in FIG. 4D at the moment the clutch is completely engaged, or the engine rotational speed decreases, and in some cases Immediately after engaging the clutch, the engine brake was to be applied, which caused a shocking feeling. Such a defect of the conventional automatic transmission is solved by gradually increasing the amount of fuel in the half-clutch state, and its characteristic is shown by the solid line in FIG.

〔The invention's effect〕

As described above, according to the present invention, when the shifting operation is ended and the clutch is engaged, the rotational speed of the diesel engine and the rotational speed of the clutch which are connected to the transmission up to the starting point of the half-clutch are substantially equal to each other. Means for controlling the number of revolutions of the diesel engine, means for judging whether or not the clutch is in the half-clutch region at the time of engaging operation of the clutch, and means for judging that the half-clutch region has been detected. , A means for forcibly gradually moving the control rack of the fuel injection pump that supplies fuel to the diesel engine to the increasing side, and forcing the control rack when the position where the control rack moves corresponds to the accelerator pedal depression amount And a means for releasing the desired movement.

Therefore, according to the present invention, the half-clutch state is started in a state where the rotation speed of the diesel engine and the rotation speed of the clutch are substantially equal to each other, after which the control rack of the fuel injection pump is forcibly moved to the increasing side. It is like this. Therefore, not only does the shock due to the difference in the number of revolutions when the clutch is engaged disappear, but also the engine braking does not work immediately after the clutch is engaged. Moreover, since the control rack is gradually moved to the increasing side in conjunction with the clutch connection operation, it is possible to prevent the torque from being reduced immediately after the clutch is engaged. In addition, since the forced movement of the control rack to the increase side is released at the position corresponding to the depression of the accelerator pedal, the manual control by the driver from the electronic control of the fuel injection pump when the clutch is engaged. A smooth transition to control is possible.

[Brief description of drawings]

FIG. 1 is a block diagram showing the gist of the present invention, FIG. 2 is a block diagram showing an automatic transmission according to an embodiment of the present invention, and FIG. 3 is an operation of clutch engagement after completion of a shift operation of the automatic transmission. FIG. 4 is a graph showing the operation of clutch engagement. In the drawings, reference numerals 10 ... Diesel engine 11 ... Fuel injection pump 15 ... Transmission 17 ... Shift actuator 18 ... Select actuator 19 ... Clutch actuator 20 ... Fuel control actuator 21 ... Microcomputer 25 ... Accelerator sensor 26 ... Vehicle speed sensor 27 ... Engine rotation sensor 30 ... Clutch.

Claims (1)

[Claims] 1. An appropriate gear position is calculated, and the gear position is automatically changed by an actuator so as to obtain a value obtained by this calculation. Is an automatic transmission in which the clutch is re-engaged when the gear position is changed and the clutch actuator is re-engaged. A means for controlling the rotational speed of the diesel engine so that the rotational speed of the coupled diesel engine and the rotational speed of the clutch are substantially equal to each other, and whether or not the half-clutch region is entered during the engaging operation of the clutch. And a means for judging, When it is detected that the control unit of the fuel injection pump for supplying fuel to the diesel engine is forcibly gradually moved to the amount increasing side when it is detected that the half-clutch region has been entered, the moving position of the control rack is the accelerator position. An automatic transmission comprising: means for canceling the forcible movement of the control rack when a position corresponding to the pedal depression amount is reached.