JPH0624898B2 - Automatic transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic truss transmission, and particularly to calculating an appropriate gear position and automatically changing the gear position by an actuator so as to obtain a value obtained by this calculation. It relates to an automatic transmission that is adapted to change its position.

[Outline of Invention]

The present invention, in an automatic transmission that automatically shifts gears to an appropriate gear position, disengages the current gear when the vehicle speed falls below a certain value, for example, just before stopping, and changes the engine speed. It is controlled so that it becomes a synchronous speed, puts in the start gear, and in this state it is made to stand by without connecting the clutch, and it is possible to start by connecting the clutch by the start signal. Is.

[Conventional technology]

Automatic transmissions have been proposed in order to avoid the driver's cumbersome shifting operations. In this automatic truss mission, the gears used by the computing means such as the microcomputer are selected according to the vehicle speed, the accelerator opening degree, etc., and the gears selected by the actuator are meshed to automatically obtain a predetermined gear ratio. It is the one. By equipping an automobile with such an automatic transmission, it is almost unnecessary to operate a lever for a shift operation of a driving vehicle.

[Problems to be solved by the invention]

In a vehicle equipped with such an automatic transmission, after the vehicle is completely stopped, the vehicle is shifted to a gear position such as a first speed, a second speed, or a reverse position where the vehicle can start. This is because the rotation of the dog clutch of the transmission does not match unless the vehicle stops, and the gear sounds when the vehicle is forced to shift without stopping. Therefore, according to the conventional transmission, when starting again, it is necessary to completely stop the vehicle and then perform a gear shift capable of starting, which is disadvantageous in that it takes time to start. In addition, the gears that can be started as described above are often composed of constant mesh gears that do not have synchronizers. There is a possibility of disappearing.

The present invention has been made in view of the above problems, and it is possible to start quickly, and further, no gear squeal occurs when shifting to a starting gear, or a dog of a constant mesh gear. An object of the present invention is to provide an automatic transmission that prevents the top parts of the clutches from hitting each other and being unable to shift to the starting gear.

[Means for solving problems]

The present invention is an automatic transmission that is connected to an engine via a mechanical clutch, wherein the engagement / disengagement of the mechanical clutch is controlled by a clutch actuator, and the automatic transmission comprises a gear type transmission. The transmission is provided with a shift actuator for selecting gears and a select actuator, and further with arithmetic means for calculating an appropriate gear position, so that the value for the shift can be obtained by the arithmetic means. In an automatic transmission in which the operation of an actuator and the operation of the select actuator are combined to change the gear position, the clutch actuator disengages the clutch to disengage the shift actuator when the vehicle speed falls below a predetermined value. A means for disengaging the gear at that time by the eater and the selecting actuator, and the clutch is connected again by the clutch actuator after the gear is disengaged, and the rotational speed of this transmission becomes a synchronous rotational speed for inserting the start gear. Means for controlling the rotation speed of the engine via the clutch, and when the rotation speed of the engine reaches a rotation speed corresponding to the synchronous rotation speed of the transmission, the clutch actuator disengages the clutch again to A means for setting a starting gear by means of the shift actuator and the selecting actuator; and, even if the starting gear is entered, waits until the starting signal is applied to the calculating means without connecting the clutch actuator by the clutch actuator. It relates an automatic transmission comprising a stage, respectively.

[Action]

Therefore, when the vehicle speed becomes equal to or lower than a predetermined value, the clutch actuator disconnects the clutch, and the shift actuator and the select actuator disengage the gear at that time. Then, after the gear is disengaged, the clutch is connected again by the clutch actuator, and the engine speed is controlled via the clutch so that the speed of the transmission becomes a synchronous speed for putting the start gear. When the rotational speed of the engine reaches the rotational speed corresponding to the synchronous rotational speed of the truss transmission, the clutch actuator disengages the clutch again, and the shift actuator and the select actuator engage the start gear. And in this state, until the start signal is added by the calculating means,
The clutch actuator is put on standby without performing the clutch connection operation.

〔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
Change the rotation speed of 0 to an appropriate value, and
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, 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, there is provided a fuel control actuator 20 for adjusting the position of the control rack to control the fuel supply amount. These four 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 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 the fuel injection pump 1
The position of the control rack No. 1 is detected. The clutch sensor 29 is attached to the tip end side of the clutch actuator 19, and the clutch 3
It is designed to detect 0 connection and disconnection states.

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 microcomputer 21 reads the map stored in the memory, and based on this map,
Calculates whether automatic gear 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.

Further, according to the automatic transmission according to the present embodiment, when the vehicle speed decreases and is about to stop, the gear is shifted to the start gear and the clutch 30 is not connected to stand by. This operation will be described with reference to the flowchart shown in FIG. 3. The microcomputer 21 reads the vehicle speed by the vehicle speed sensor 26, and determines whether the vehicle speed is just before the stop, that is, a certain low value or less. When the value becomes equal to or less than a certain value on the verge of stopping, the clutch 30 is disengaged by the actuator 19. After that, according to an instruction from the microcomputer 21, the current gear is disengaged using the shift actuator 17 and the select actuator 18.

After this, the microcomputer 21 connects the clutch 30 again by the clutch actuator 19, reads the rotation speed of the engine 10 by the rotation detection sensor 27, and raises or lowers the rotation speed of the engine 10. Then, it is determined whether or not the rotation speed of the engine 10 has reached the rotation speed for putting in the starting gear, and when the rotation speed of the engine 10 matches the synchronous rotation speed, the clutch 19 is disengaged by the actuator 19 again. . Then, after this, the actuators 17 and 18 are used to shift to the starting gear, for example, the first speed or the second speed. In this way, a series of gear shift operations are completed, and the clutch 30 is not connected and the vehicle stands by in this state.

Therefore, in this state, if the clutch 30 is connected, the vehicle can be started at any time. Then, the microcomputer 21 determines whether or not there is a start signal, and when there is a start signal, the actuator 19
Thus, the clutch 30 is connected and the starting operation is performed.

Generally, the shift control of the mechanical automatic transmission is ended by finally engaging the clutch. However, here, a start preparation program is provided in which only the last clutch 30 is connected. Then, when the running state is changed to the stopped state and the vehicle is about to stop, this program is used to change the gear position to a gear position in which the vehicle can start.
The shift to the starting gear is performed by adjusting the rotational speed of 0 to the synchronous rotational speed.

If such control is not performed, the rotations of the dog clutches are not matched and the vehicle cannot shift to the start gear unless the vehicle stops. Further, if the gears are forcedly shifted without synchronizing the rotation speeds, gear squeal will occur. Further, if the vehicle is stopped and then the shift gear is tried to be engaged, the dog clutch may be caught, and there is a possibility that the shift cannot be performed. However, gear squealing and dog clutch catching are prevented by shifting gears in synchronism with rotation. Further, since the clutch is not connected and the vehicle is on standby, the starting signal can be improved by simply connecting the clutch 30 by supplying the starting signal.

〔The invention's effect〕

As described above, according to the present invention, when the vehicle speed becomes equal to or lower than the predetermined value, the clutch actuator disengages the clutch, the shift actuator and the select actuator disengage the gear at that time, and the clutch actuator reconnects the clutch. The engine rotation speed is controlled so that the transmission rotation speed becomes the synchronous rotation speed, the clutch actuator disengages the clutch again, and the shift actuator and select actuator engage the start gear, and the start signal is calculated. The actuator waits without engaging the clutch until it is added.

Therefore, according to the present invention, when the vehicle speed becomes equal to or lower than the predetermined value, the rotation speed of the transmission is forcibly set to the synchronous rotation speed by controlling the rotation speed of the engine before the vehicle stops. It becomes possible to shift to the starting gear in this state by controlling and synchronizing. That is, it becomes possible to shift to the starting gear before the vehicle stops. Moreover, when shifting to such a starting gear,
Because the transmission speed is synchronized by the engine via the clutch,
No special synchronism means is used and no gear squeal is generated during the shift operation. Also, because the vehicle shifts to the start gear before it stops,
Since the gears are shifted in synchronization with the rotation, the inconvenience of being unable to shift due to the dog clutch being caught can be eliminated. This makes it possible to smoothly shift to the start gear immediately before the vehicle stops.

Further, since the clutch actuator is not engaged by the clutch actuator in the state where the start gear is engaged and the clutch is disengaged and waits until the start signal is applied to the calculation means, the clutch actuator is immediately supplied with the start signal. The clutch is connected by means of this, which enables a quick start operation and improves the startability. Therefore, the startability of the automatic transmission can be improved.

[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 truss mission according to an embodiment of the present invention, and FIG. 3 shows a shift operation to a starting gear of this automatic transmission. It is a flowchart. In the reference numerals used in the drawings, 10 ... Diesel engine 15 ... Transmission 17 ... Shift actuator 18 ... Select actuator 19 ... Clutch actuator 21 ... Microcomputer 25 ... Accelerator sensor 26 ... Vehicle speed sensor 27 ...... Engine rotation sensor 30 ...... It is a clutch.

Claims (1)

[Claims] 1. An automatic transmission connected to an engine via a mechanical clutch, wherein engagement and disengagement of the mechanical clutch is controlled by a clutch actuator, and the automatic transmission comprises a gear type transmission, The transmission is provided with a shift actuator for selecting gears and a select actuator, and further with arithmetic means for calculating an appropriate gear position, so that the shift is performed so that the value obtained by the arithmetic means becomes a value. In an automatic transmission in which the gear position is changed by combining the operations of the actuator for selection and the actuator for selection, when the vehicle speed falls below a predetermined value, the clutch actuator disengages the clutch to disengage the shift actuator. A means for disengaging the gear at that time by the eater and the select actuator, and the clutch is connected again by the clutch actuator after the gear is disengaged, and the rotation speed of this transmission becomes a synchronous rotation speed for inserting the start gear. Means for controlling the rotation speed of the engine via the clutch, and when the rotation speed of the engine reaches a rotation speed corresponding to the synchronous rotation speed of the transmission, the clutch actuator disengages the clutch again to A means for setting a starting gear by means of the shift actuator and the selecting actuator; and, even if the starting gear is entered, waits until the starting signal is applied to the calculating means without connecting the clutch actuator by the clutch actuator. Automatic transmission comprising the steps, respectively.