JP4152111B2 - Automatic transmission system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic transmission system for performing engine rotation restriction control in a vehicle having an engine equipped with an electronically controlled fuel injection device and an automatic transmission equipped with a mechanical clutch, and a start control method therefor.
[0002]
[Prior art]
In a transmission that electrically shifts a mechanical transmission using an electrical signal, a semi-automatic transmission that is configured to manually operate a clutch when starting and to be an automatic clutch during traveling is a control device that controls clutch pedal operation during traveling. Or the automatic clutch actuator is mechanically canceled (see, for example, Japanese Utility Model Laid-Open No. 60-69855 and Japanese Utility Model Laid-Open No. 62-102056 by the present applicant). .
[0003]
Further, in the same semi-automatic transmission as described above, the clutch meet point is learned, and a clutch stroke at the time of shifting is determined from the control map in accordance with this learned value (for example, Japanese Utility Model Application No. 6-8825 by the present applicant). Has been proposed).
[0004]
However, the above-described semi-automatic transmission does not have an automatic start control function, and when performing automatic start control, the elapsed time from the start of start and the manner in which the engine speed increases with respect to the clutch stroke are problematic. .
[0005]
In other words, if the driver depresses the accelerator with sufficient margin without taking care to adjust the accelerator with automatic start, the clutch will automatically operate and the shift gear should be shifted up, but if the accelerator opening is too large, the engine The rotational speed increases unnecessarily, resulting in a problem that the clutch load increases and the life of the clutch is shortened.
[0006]
[Problems to be solved by the invention]
The present invention has been proposed in view of the above-described problems of the prior art, and the clutch slippage is controlled by controlling the engine speed to a predetermined speed or less regardless of the clutch transmission load at the time of automatic start. It is an object of the present invention to provide an automatic transmission system and a start control method thereof that suppresses clutch wear with a minimum and suppresses the generation of shocking start torque and improves the start acceleration feeling.
[0007]
[Means for Solving the Problems]
According to the present invention, the accelerator opening sensor 4a that detects the accelerator opening, the engine rotation sensor 1a that detects the engine rotation speed, the gear rotation sensor 3a that detects the gear rotation speed of the transmission, and these accelerator opening degrees. In the automatic transmission system having a mechanical clutch provided with a control means 10 for outputting a control signal to the engine control unit 9 based on input information from the sensor 4a, the engine rotation sensor 1a and the gear rotation sensor 3a, the engine control The unit 9 has a rotation speed limit mechanism and a torque suppression mechanism, and performs engine speed limit control when it is determined that the vehicle is in a starting state based on input information from the accelerator opening sensor 4a and the gear rotation sensor 3a. Control signal and accelerator opening exceeds a certain value In this case, the control means 10 is configured to transmit a control signal for controlling the starting torque. Whether the engine rotation restriction start condition is satisfied from the detection signals of the accelerator opening sensor 4a and the gear rotation sensor 3c. If the rotation restriction start condition is satisfied, the engine speed is plotted on the horizontal axis, and the accelerator opening is plotted on the vertical axis. As a point, the engine speed information and the gear speed information are requested by requesting a speed limit to limit the injection amount so as to trace a governor line having a gradient that the engine speed becomes small when the accelerator opening becomes large. Based on this, it is determined whether or not the value obtained by subtracting the gear speed of the transmission 3 from the engine speed is a half-clutch state within a predetermined value. The rotation restriction request is terminated, and it is determined whether or not the accelerator opening exceeds a predetermined value from the detected value of the accelerator opening sensor 4a, and torque suppression control is performed, so that the driver's requested starting torque is less than the actual starting torque. Whether the required starting torque is equal to or less than the actual starting torque, the torque suppression control is terminated.
[0008]
In the present invention, the control means is divided into a first control unit (20) for controlling the electronically controlled fuel injection pump (9A) and a second control unit (30) for controlling the automatic transmission. The first control unit (20) controls the rotation limit and torque limit to the fuel injection pump (9A), and is connected to the second control unit (30) via the communication line (L) to share information. I'm crazy.
[0013]
According to the automatic transmission system of the present invention having such a configuration, the slippage of the clutch can be minimized by controlling the engine speed to an arbitrary predetermined speed or less regardless of the transmission load of the clutch at the time of automatic start. Limit the wear of the clutch.
[0014]
As a result of the suppression of clutch wear, the clutch life is extended and an economic effect is obtained, and the maintenance interval is extended.
[0015]
Further, by detecting the condition that the starting torque becomes excessive, the generation of shocking starting torque is suppressed in advance, and the feeling of starting acceleration is improved.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0017]
1 to 5 show a first embodiment. In FIG. 1, a gear to which engine-side rotational force is transmitted is connected to an engine 1 having an engine rotation sensor 1 a via a clutch 2. A transmission 3 having a gear rotation sensor 3a for determining whether or not it has been detected and detecting the rotation speed of the gear is attached.
[0018]
The accelerator pedal 4 is provided with an accelerator opening sensor 4a. The accelerator opening sensor 4a, the engine rotation sensor 1a, and the gear rotation sensor 3a are controlled by input signal lines L4, L1, and L3 in the order of signs. It is connected to a certain transmission control unit (hereinafter referred to as TM control unit) 10.
[0019]
The TM control unit 10 is connected to an engine control unit 9 having a rotation speed limiting mechanism and a torque suppression mechanism via an output signal line Lo, and receives input information from the accelerator opening sensor 4a and the gear rotation sensor 3a. Based on this, a control signal (output signal) for performing engine rotation restriction control is transmitted when it is determined that the vehicle is in a starting state, and a control signal for suppressing starting torque is transmitted when the accelerator opening exceeds a certain value. Is configured to do.
[0020]
Next, a control method is demonstrated based on FIGS.
In step S1 (measurement step), the accelerator opening sensor 4a detects the accelerator opening, and the gear rotation sensor 3a detects whether the engine rotation is connected to the transmission gear.
[0021]
In the next step S2 (start determination step), the TM control unit 10, which is a control means, determines whether or not an engine rotation restriction start condition is satisfied.
[0022]
When the rotation restriction start condition is satisfied (for example, when the accelerator is depressed and the accelerator opening is equal to or greater than the first predetermined value and the engine speed is connected to the transmission gear / YES in step S2), the process proceeds to the next step S3. The engine control unit 9 is requested to restrict the advance rotation, and the process proceeds to step S4.
[0023]
If the rotation restriction start condition is not satisfied (NO in step S2), the process proceeds to step S6.
[0024]
In step S4, the engine speed information detected by the engine speed sensor 1a and the gear speed sensor 3a (the gear speed sensor 3a detects whether the engine speed is connected to the gear and the gear speed). The difference between the engine speed and the transmission input speed, that is, the value obtained by subtracting the gear speed of the transmission 3 from the engine speed is a predetermined value (for example, 30 rpm). It is determined whether the half clutch state is within.
[0025]
If the difference between the engine speed and the transmission input speed is within a predetermined value, that is, if the clutch is in a half-clutch state (YES in step S4), the process proceeds to step S5, where the clutch state is changed from the half-clutch state. Since it becomes unnecessary, the rotation restriction request is terminated, and the process proceeds to the next step S6.
[0026]
If the rotational speed difference exceeds the predetermined value in step S4 (if NO), the process returns to step S3.
[0027]
In step S6, the TM control unit 10 determines whether or not the torque limiting condition is satisfied, that is, whether or not the accelerator opening exceeds a predetermined value from the detected value of the accelerator opening sensor 4a. If it is (YES), it will progress to step S7, and if it is not materialized (if it is NO), control will be complete | finished.
Here, when the engine speed control is finished when the accelerator pedal is so-called "stomping", the engine speed and the vehicle speed rapidly increase as shown by the VA line (vehicle speed) and the NA line (engine speed) in FIG. This will shock the driver. Therefore, in order to avoid such a situation, the control after step S7 is performed.
[0028]
In step S7, the TM control unit 10 performs a torque suppression control by transmitting a control signal to the engine control unit 9 via the output signal line Lo so as to reduce the fuel injection amount, for example. Upon receiving the output signal, the engine control unit 9 reduces the amount of injection and reduces the shock by reducing the engine speed and vehicle speed as shown by the Va line (vehicle speed) and Na line (engine speed) in FIG. Proceed to step S8.
[0029]
In step S8, the TM control unit 10 determines whether or not the driver's required starting torque is still below the actual starting torque. If the required starting torque is below the actual starting torque (YES), step TM8 is performed. Proceeding to S9, the torque suppression control is terminated. If the requested start torque is not less than the actual start torque (NO in step S8), the process returns to step S7 and the control is repeated.
[0030]
According to the automatic transmission system and the start control method in the first embodiment of FIGS. 1 to 5 provided with such a configuration and control method, as a specific method of the rotation restriction request in step S3 in the control flow of FIG. As shown in the governor map in FIG. 4, a governor line having an inclination (shown by a broken line) as shown in the figure with an arbitrary speed limit (point Ns in FIG. 4) as a reference point at the time of clutch meet when starting the vehicle. The rotation limit is controlled by controlling the injection amount so as to trace. By performing control based on the rotation restriction request in this way, it is possible to reduce clutch wear in the half clutch.
[0031]
The governor line (broken line portion) applied to the governor map in FIG. 4 has substantially the same action as the governor map shown in FIG. 5 and controls the rotation restriction request by diverting the high idle control. For this reason, even if there is a load change, it becomes a flexible behavior with respect to the restriction only by moving up and down on the governor line.
[0032]
Further, the start torque suppression control is performed according to the accelerator opening, thereby facilitating the start particularly in a commercial vehicle having a large load difference between an empty vehicle and a loaded vehicle.
[0033]
FIG. 6 shows a second embodiment. In contrast to the configuration shown in FIG. 1, the control means is divided into a first control unit 20 for controlling the electronically controlled fuel injection device 9A and a second control unit 30 for controlling an automatic transmission (ATM). It is a thing. The function and the control method are the same as in FIG. 2, but the first control unit 20 controls the fuel injection device 9A by sending a rotation limit request and a torque suppression control signal. The information is shared by being connected to two control units 30. The second control unit 30 performs automatic transmission control of the transmission, but this unit may be 30 or an external unit. If the control unit is divided in this way, it is possible to reduce the time and cost of creating a program.
[0034]
FIG. 7 shows the control of the governor line as a two-dimensional map in the second control unit 30 in the second embodiment of FIG. 6, and fine rotation restriction control can be achieved by controlling in this way.
[0035]
【The invention's effect】
The effects of the present invention are listed below.
(1) By controlling the engine speed below an arbitrary speed, clutch slippage is minimized and clutch wear is suppressed regardless of the clutch transmission load during automatic start.
(2) As a result of suppressing clutch wear, the clutch life is extended and an economic effect is obtained, and the maintenance interval is extended.
(3) By detecting the condition that the starting torque becomes excessive, it is possible to suppress the generation of shocking starting torque and to improve the feeling of starting acceleration.
(4) By performing the start torque suppression control according to the accelerator opening, it is possible to make the start easy especially in commercial vehicles having a large load difference between empty and loaded vehicles.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an automatic transmission system according to a first embodiment of the present invention.
FIG. 2 is a control flowchart according to the first embodiment of the present invention.
FIG. 3 is a characteristic diagram showing changes in engine speed and vehicle speed when the engine speed limit control is performed and when it is not performed.
FIG. 4 is a governor map for comparison between when the control according to the first embodiment of the present invention is not performed and when the control is not performed.
FIG. 5 is a governor map in the case of performing control according to the first embodiment of the present invention.
FIG. 6 is an overall configuration diagram of an automatic transmission system according to a second embodiment of the present invention.
FIG. 7 is a governor map in the case of performing control according to the second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Engine 1a ... Engine rotation sensor 2 ... Clutch 3 ... Transmission 3a ... Gear rotation sensor 4 ... Accelerator pedal 4a ... Accelerator opening sensor 9 ... Engine control unit 10 ... TM control units L1, L3, L4 ... Input signal line Lo ... Output signal line

Claims (2)

  An accelerator opening sensor (4a) for detecting the accelerator opening, an engine rotation sensor (1a) for detecting the engine speed, a gear rotation sensor (3a) for detecting the gear speed of the transmission, and the accelerator opening A mechanical clutch provided with a control means (10) for outputting a control signal to the engine control unit (9) based on input information from the sensor (4a), the engine rotation sensor (1a) and the gear rotation sensor (3a). In the automatic transmission system, the engine control unit (9) has a rotation speed limiting mechanism and a torque suppression mechanism, and starts based on input information from the accelerator opening sensor (4a) and the gear rotation sensor (3a). If it is determined that the engine is in a state, a control signal for engine speed limit control is When the accelerator opening exceeds a certain value, a control signal for controlling the starting torque is transmitted, and the control means (10) first includes an accelerator opening sensor (4a) and a gear rotation sensor (3c). Is determined from the detection signal, and when the rotation restriction start condition is satisfied, the governor map is obtained by taking the engine speed on the horizontal axis and the accelerator opening on the vertical axis. Rotation that limits the injection amount so as to trace a governor line that has a slope where the engine speed decreases as the accelerator opening increases, with the speed limit (Ns) at clutch meet when starting the vehicle as a reference point When the limit is requested, the value obtained by subtracting the gear speed of the transmission (3) from the engine speed based on the engine speed information and the gear speed information is within a predetermined value. If it is within the predetermined value, the rotation restriction request is terminated, and it is determined whether the accelerator opening exceeds the predetermined value from the detected value of the accelerator opening sensor (4a). The torque suppression control is performed, and it is determined whether or not the driver's required starting torque is equal to or less than the actual starting torque. If the required starting torque is equal to or less than the actual starting torque, the torque suppressing control is terminated. An automatic transmission system characterized by that.   The control means is divided into a first control unit (20) for controlling the electronically controlled fuel injection pump (9A) and a second control unit (30) for controlling the automatic transmission, and the first control unit (20 ) Performs control of rotation limitation and torque limitation to the fuel injection pump (9A) and is connected to the second control unit (30) by the communication line (L) to share information. The automatic transmission system described.

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