JPS61129346A - Automatic transmission - Google Patents

Abstract

PURPOSE:To allow an automatic transmission to be provided with a function of creep operation by prohibiting the start operation and allowing the creep operation when it is sensed that a brake is being operated. CONSTITUTION:A service brake sensor 30 and a parking brake sensor 31 connected to the input side of a microcomputer 21 sense whether each brake is in the operation state. In addition, if both brakes are not operated, a transmission 15 is switched to the first speed or back gear and a clutch is connected by a clutch actuator 19 to perform creep operation.

Description

[Detailed description of the invention]

FIELD OF INDUSTRIAL APPLICATION The present invention relates to an automatic transmission in which a clutch is switched to a disengaged state and selected gears are engaged to obtain a predetermined gear ratio.

[Prior art]

In order to change the rotational speed of an automobile engine to an appropriate value, a transmission has conventionally been attached to the engine. In this transmission, the gear to be used is selected in response to the driver's gear change operation, and the engine speed is changed to an appropriate value and transmitted 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. Automatic transmissions have been proposed to overcome these drawbacks. 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 an automobile with such an automatic transmission, the driver hardly needs to operate a lever to change gears. However, in the case of automatic transmissions equipped with semi-dry or dry clutches instead of using fluid-type clutches, they cannot release torque like fluid-type clutches can, so they move the vehicle slowly forward or backward. However, it was not possible to provide a function to perform a creep operation. When an automatic transmission equipped with a semi-dry or dry clutch is provided with a creep function, a large load is applied to the clutch, causing the clutch facing to burn out.

[Purpose of the invention]

The present invention has been made in view of these problems, and provides a mechanical transmission in which a clutch is switched to a disengaged state using an actuator to change gears, and a creep operation function can be added to the mechanical transmission. The purpose is to provide an automatic transmission with K Structure of the Invention] The present invention selects a gear to be used by a calculating means according to vehicle speed, accelerator opening degree, etc., switches a clutch to a disengaged state by an actuator, and meshes the selected gear to set a predetermined gear. In an automatic transmission designed to obtain a ratio, a detection means for detecting whether or not the brake is in operation is provided, and if the detection means detects that the brake is in operation, the starting operation is prohibited, thereby preventing creep operation. The present invention relates to an automatic transmission characterized in that the automatic transmission has a dry or semi-dry clutch and is provided with a creep operation function. EXAMPLE 1 The present invention will be described below with reference to an illustrated example. FIG. 1 shows an engine for an automobile 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 a 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
The rotational speed of the engine is changed to an appropriate value and transmitted to the driving wheels via the roller shaft 16. The transmission 15 constitutes an automatic transmission, and a shift actuator 17 and a selection actuator 18 are provided above the transmission. 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 that is mounted roughly 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 amount of fuel supplied. 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 connected to the speed change (-23. It's turning into a sea urchin. Further, the microcomputer 21 includes a vehicle speed sensor 26, an engine rotation sensor 2-a rack sensor 28,
and two Taranochi 7 pumps. 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, an engine rotation sensor 2.7 is attached to the front side of the engine 10 to detect the rotation speed of the engine 10.A rack sensor 28 is attached to the tip side of the actuator 20. The clutch sensor 29 detects the position of the control rack of the fuel injection pump 11.Furthermore, five clutch sensors 29 are attached to the tip side of the clutch actuator 19, and detect the connection and disconnection state of the clutch. Furthermore, in the automatic transmission according to this embodiment, as shown in FIG. Brake sensors 31 are connected to each other.These sensors 30 and 31 are designed to detect whether or not the service brake and parking brake are in operation.Such service brake sensors 30F3 and parking brake Ginsa 31
By providing the automatic transmission 15 with a dry or semi-dry clutch whose connection and disconnection are controlled by the clutch actuator 19, it is possible to provide a creep operation function. 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 memory of the microcomputer 21, and the speed change operation is performed automatically when the shift lever 23 of the control box 22 is in the automatic position. It has become. On the other hand, when the shift lever 23 is in the manual position, a manually selected shift operation is carried out via the actuators 17, 18. 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 amount or accelerator opening degree and vehicle speed are read from the accelerator sensor 25 and 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. In addition, during this shift operation, the clutch is switched to the disconnected state by one actuator, and the clutch is brought into the engaged state again in synchronization with the end of the shift operation. Roughly speaking, according to the automatic transmission according to this embodiment, the service brake sensor 30 and the parking brake sensor 31 are connected to the input side of the microcomputer 21 as described above. , 31 detect whether or not the service brake and parking brake are activated, thereby providing a creep operation function. This action is the second
The process is carried out based on the flowchart shown in the figure, and the detection outputs of the sensors 30 and 31 are read, and these detection outputs are used to control the microcomputer 21.
The system detects whether the service brake or parking brake is in operation. If neither brake is in operation, calculations are performed and the vehicle is enabled to start. This starting output causes the clutch actuator 19 to
Since the clutch is switched to the connected state, the vehicle starts moving. This therefore causes a creep operation. Furthermore, when the service brake or parking brake is in operation, as is clear from the flowchart shown in FIG.
5 is held in a neutral state and no creep takes place since no launch takes place. As described above, in the automatic transmission according to this embodiment, the service brake sensor 30 and the parking brake sensor 31 are installed, and these sensors 30.3
1, when both the service brake and the parking brake are not operated, the transmission 15 is switched to first speed or reverse, and the clutch is connected by the clutch actuator 19 to cause creep. Therefore, it becomes possible to slowly move the vehicle little by little in one direction or backwards only by operating the brake pedal or parking brake lever, making it possible to safely and accurately park the vehicle. Moreover, this creep action is interrupted by depressing the brake pedal or pulling the parking brake lever - the clutch is disengaged, so there is no significant load on the clutch, and the problem of burnout of the clutch facing is eliminated. be able to. In the case of vehicles such as large vehicles and trailer trucks, this type of leap function not only enables safer and more accurate parking for vehicles such as large vehicles and trailer trucks, but also makes driving easier by assisting the driver's driving operations. It becomes possible to provide vehicles. [Effects of the Invention] As described above, the present invention provides a detection means for detecting whether or not the brake is in operation, and prohibits the starting operation when the detection means detects that the brake is in operation. This enables the creep operation. Therefore, according to the present invention, it is possible to provide a creep operation function to an automatic transmission equipped with a dry or semi-dry clutch.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an automatic transmission according to an embodiment of the present invention, and FIG. 2 is a flow chart showing the creep operation of this automatic transmission. In the symbols used in the drawings, 15... Transmission 17... Shift actuator 18... Select actuator 19... Clutch actuator 21... Microcomputer 25... Accelerator sensor 26... Vehicle speed Sensor 30...Service brake sensor 31...Parking brake sensor.

Claims (1)

[Claims] An automatic system in which a calculation means selects a gear to be used according to vehicle speed, accelerator opening, etc., and an actuator switches a clutch to a disengaged state and engages the selected gear to obtain a predetermined gear ratio. The transmission is provided with a detection means for detecting whether or not the brake is in operation, and when this detection means detects that the brake is in operation, the creep operation is enabled by prohibiting the start operation. An automatic transmission characterized by: