JPH0741808B2 - Automatic transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission, and particularly to calculating an appropriate gear position and automatically changing the gear position to a gear position obtained by this calculation by an actuator. The present invention relates to an automatic transmission whose position is changed, and further to a suitable one used for an automatic transmission in which a mechanical clutch and a gear transmission are controlled by a microcomputer to perform an automatic transmission operation.

[Outline of Invention]

According to the present invention, when the engine of a vehicle equipped with an automatic transmission is started and after the start of the engine and the accelerator pedal is not depressed, the clutch is connected to drive the transmission, thereby quickly warming up the transmission. In addition, the clutch is disengaged when the accelerator pedal is depressed to reduce the load at the time of starting and improve the starting performance.

[Conventional technology]

BACKGROUND ART Automatic transmissions have been put into practical use in order to reduce driver's complicated shifting operations and facilitate driving operations. This automatic transmission inputs a signal from a sensor that detects a vehicle speed, an accelerator opening, etc. to select a gear used by a computing means such as a microcomputer, and automatically meshes the gear selected by an actuator with a predetermined gear. The gear ratio of is obtained. By equipping an automobile with such an automatic transmission, the lever operation for the driver to shift gears becomes almost unnecessary. As a prior art related to the present invention, for example, there is JP-A-52-127559, but there is no description relating to the gist of the present invention.

[Problems to be solved by the invention]

The clutch used in a conventional manual transmission is in an engaged state when the clutch pedal is not depressed. However, the electronically controlled mechanical automatic transmission is designed so that the clutch is disengaged when the vehicle is stopped or the engine is not started from the viewpoint of vehicle safety. In such an automatic transmission, the clutch is disengaged when the engine is started, so that the transmission does not rotate. Therefore, the transmission cannot be warmed up. If the clutch is connected at the time of starting the engine in order to solve such a drawback, there is a drawback that the load applied to the engine increases.

The present invention has been made in view of the above problems, and provides an automatic transmission that reduces the load at the time of starting the engine and can quickly warm up the inside of the transmission as needed. The purpose is to do.

[Means for solving problems]

As shown in FIG. 1, the present invention calculates an appropriate gear position and automatically changes the gear position by an actuator so that the value obtained by this calculation is used to start an engine. If the vehicle is not running and the vehicle is stopped at the time of starting the engine and after the engine is started and the gear position is in neutral, the clutch is engaged or disengaged depending on whether or not the accelerator pedal is depressed. With a means for controlling, the clutch is disengaged at the time of starting the engine and when the accelerator pedal is depressed after the starting,
The present invention relates to an automatic transmission in which a clutch is connected to drive a transmission when the accelerator pedal is not depressed.

[Action]

Therefore, when the accelerator pedal is depressed when the engine is started and after the engine is stopped, and the gear position of the transmission is neutral, the clutch is disengaged. Therefore, the interlock between the engine and the transmission is cut off, and the transmission is not driven by the engine. Therefore, it is possible to reduce the load on the engine.

On the other hand, when the accelerator pedal is not depressed, it is considered that the driver wants warm-up operation and the clutch is engaged. Therefore, the engine and the transmission are transmitted via the clutch, and the engine drives the transmission. Therefore, the transmission is warmed up quickly.

〔Example〕

The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 2 shows an automobile engine equipped with an automatic transmission according to an embodiment of the present invention. The diesel engine 10 includes a fuel injection pump 11, and the pump 11
The fuel is sequentially supplied 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. Further, the fuel injection pump 11 includes a mechanical governor 13, and the governor 13 adjusts the fuel injection amount.

A flywheel housing 14 is provided on the back side of the engine 10, and the flywheel fixed to the end of the crankshaft is housed in the housing 14. A clutch 30 is provided on the back side of the flywheel, and the clutch 30
A transmission 15 is attached to the rear side of the flywheel housing 14 so as to be connected to the transmission 15. The transmission 15 changes the number of revolutions of the engine 10 to a predetermined value and transmits it to the drive wheels via a propeller shaft 16.

The transmission 15 constitutes an automatic transmission, and the shift actuator 17 is provided above it.
And a select actuator 18 are provided respectively. Further, a clutch actuator 19 for controlling connection and disconnection of the clutch 30 mounted on the rear side of the flywheel is mounted on the outer surface of the casing of the transmission 15. Further, on the front end side of the fuel injection pump 11, a fuel control actuator (linear solenoid) 20 for adjusting the position of the control rack to control the fuel supply amount is provided. The linear solenoid 20 cooperates with the microcomputer 21 to form an electronic governor, and when electronically controlling the engine 10, the mechanical governor 13 is prioritized to move the control rack. The four actuators 17, 18, 19, 20 are driven based on an instruction from the microcomputer 21 via air or electric 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 which detects the accelerator opening degree or the depression amount of the accelerator pedal 24. Further, the microcomputer 21 is connected to the vehicle speed sensor 26, the engine rotation sensor 27, the rack sensor 28, the clutch sensor 29, and the gear position sensor 31, respectively.

The vehicle speed sensor 26 is provided on the side surface of the transmission 15, and the vehicle speed is detected 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.
The rack sensor 28 is attached to the tip end side of the actuator 20 and detects the position of the control rack of the fuel injection pump 11. The clutch sensor 29 is attached to the tip end side of the clutch actuator 19 and detects the connection and disconnection states of the clutch 30. The gear position sensor 31
Is provided on the upper part of the transmission 15 and detects where the gear is shifted.

Next, the operation of the automatic transmission having the above configuration 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 speed change position, the speed change operation is automatically performed. ing. On the other hand, when the speed change lever 23 is at the manual position, the manually selected speed change operation is performed via the actuators 17 and 18.

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 shift position. In the case of the automatic shift position, the accelerator pedal 24 is operated at a constant cycle. The depression amount or accelerator opening degree, vehicle speed, and engine speed are read from the accelerator sensor 25, the vehicle speed sensor 26, and the engine rotation sensor 27, respectively. Further, the microcomputer 21 reads a map stored in the memory and, based on this map, calculates whether automatic shift is possible or not. 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.

A specific operation of the automatic shift is based on a command from the microcomputer 21, and an electromagnetic valve (not shown) is actuated to send air from the air tank to the shift actuator 17 and the select actuator 18, and the respective actuators 17 and 18 are operated.
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 shift operation, the clutch 30 is temporarily switched to the disengaged state by the actuator 19, and the clutch 30 is controlled to be in the engaged state again in synchronization with the end of the shift operation.

The transmission 15 that automatically shifts in this way
The transmission 15 can be warmed up as necessary when the engine 10 connected to the engine is started. This operation is performed by the microcomputer 21
According to the flowchart shown in FIG. The microcomputer 21 reads the position of the speed change lever 23 of the control box 22 and determines whether this position is neutral. If it is not neutral, start is prohibited. On the other hand, when the speed change lever 23 is in the neutral position, the engine can be started. Therefore, the engine 10 is started in this state. Whether or not the engine is started is detected by whether or not the engine 10 is rotating, and when the engine 10 is rotating, it is determined that the starting is completed.
On the other hand, when the engine 10 is not rotating, the clutch 30 is disengaged because it has not been started.

When the engine 10 is started and its rotation is started, after this, the microcomputer 21 operates the accelerator pedal.
The accelerator sensor 25 detects the depression of 24. When the accelerator pedal 24 is depressed, the clutch is disengaged. Therefore, in this case, the torque is not transmitted to the transmission 15 and the transmission 15
No fifteen loads are added to the engine 10. This makes it possible to reduce the load.

On the other hand, when the accelerator pedal 24 is not depressed after the engine 10 is started, the gear position sensor 31 detects the gear position of the transmission 15, and
Determine if the gear position is in neutral. In the case of neutral, the clutch 30 is connected so that the engine 10 drives the countershaft of the transmission 15 to quickly warm up the transmission 15. On the other hand, transmission
When the gear position of 15 is not neutral, the transmission 15 is switched to neutral by the actuators 17 and 18. This is to prevent the vehicle from accidentally starting traveling during warm-up.

Thus, according to the transmission 15 of this embodiment,
During normal start-up, the accelerator pedal 24 is depressed to cut off the clutch 30 to reduce the load, and when warm-up is required, release the accelerator pedal 24 after start-up to connect the clutch 30 and the transmission 15 The counter shaft is rotated to warm up the inside of the transmission 15. This makes it possible to reduce the load at the time of starting and warm up the inside of the transmission 15 at the same time.

〔The invention's effect〕

As described above, the present invention is to increase the engine speed when the accelerator pedal is stepped on when the vehicle is stopped and after the engine is started and the gear position is neutral. Since the clutch is disengaged at this time, even when the engine is starting, especially when it is cold and the oil temperature is low and the rotation resistance of the gear of the transmission is large, the engine is not affected by the resistance of the transmission. Can be started. On the other hand, when the accelerator pedal is not depressed, it is regarded as warm-up operation and the clutch is engaged, so that the gear of the transmission rotates and the oil temperature of the transmission can be raised.

[Brief description 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 one embodiment of the present invention, and FIG. 3 is a flowchart showing a warm-up operation at the time of starting. In the reference numerals used in the drawings, 15 ... Transmission 17 ... Shift actuator 18 ... Select actuator 19 ... Clutch actuator 21 ... Microcomputer 22 ... Control box 24 ... Accelerator pedal 25 ... Accelerator sensor 30 ...... It's a clutch.

Claims (1)

[Claims] 1. A transmission in which an appropriate gear position is calculated and the gear position is automatically changed by an actuator so as to obtain a value obtained by the calculation, and the clutch is used when the engine is not started. And a means for controlling engagement / disengagement of the clutch depending on whether or not the accelerator pedal is depressed when the vehicle is stopped at the time of starting the engine and after the engine is started and the gear position is in neutral. When the accelerator pedal is stepped on and after the engine is started, the clutch is disengaged, and when the accelerator pedal is not stepped on, the clutch is connected to drive the transmission. An automatic transmission characterized by that.