JP2004293371A - Vehicle speed limiting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a vehicle speed limiting function (including a function to temporarily cancel vehicle speed limits during gear shift) inexpensive in a vehicle with automatic transmissions. <P>SOLUTION: The vehicle with automatic transmissions is provided with an engine control unit 12 controlling to an engine revolution/engine torque according to an accelerator opening or a control command for automatic gear shift, a transmission control unit 11 controlling connection/disconnection of a clutch and the gear shift of a transmission so as to automatically shift to a target shift stage matched with operating condition, a communicating means exchanging control command between the unit 12 and the unit 11, and a means artificially manually controlling the connection/disconnection of the clutch, the gear shift of the transmission and the accelerator opening of an engine. In the vehicle with automatic transmissions, means (S1-S4) canceling vehicle speed limits during gear shift that does not receive the control command from the transmission control unit 11 are set to the engine control unit 12. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a speed limiting device for an automatic transmission vehicle.
[0002]
[Prior art]
The speed limiting device controls the engine speed so that the vehicle speed does not exceed the limit value. Due to the relationship with vehicle shifting, the clutch may be depressed and the accelerator depressed in order to match the engine rotation with the gear rotation when downshifting. Because it is suppressed, it is possible that the engine rotation may not be adjusted properly.
[0003]
In the conventional example, there is provided a switch which is turned on when the clutch pedal is depressed, and a means for temporarily releasing the vehicle speed limit while the switch is turned on. Since it is set to be turned on when the pedal is depressed to the extent that the clutch is half-engaged, the vehicle speed limitation can be intentionally released by operating the pedal, not for adjusting the rotation of the engine during downshifting. Therefore, there is disclosed a device in which a switch for detecting the neutral position of the shift lever is provided to allow the release of the vehicle speed limitation only during the gear shift (Japanese Patent Application Laid-Open No. H10-163,086).
[0004]
In order to achieve both fuel economy and easy drive, there is an electronically controlled mechanical type automatic transmission which is mainly used for large vehicles (Patent Document 2). This system performs an engine control unit that controls the engine rotation / engine torque according to the accelerator opening or the engine rotation / engine torque according to the automatic shift control command, and performs an automatic shift to a target stage according to the operating state. A transmission control unit for controlling the on / off operation of a clutch (mechanical friction clutch) and the gear shift of a transmission (gear-type transmission), communication means for exchanging control commands between these units, the on / off operation of the clutch and the transmission Means for manually manually controlling the gear shift and the accelerator opening of the engine.
[0005]
[Patent Document 1]
JP-A-11-351000 [Patent Document 2]
JP-A-2001-227630
[Problems to be solved by the invention]
It is conceivable to add a speed limiting function (including a function of temporarily releasing the vehicle speed limit during shifting) also in such an automatic transmission. In that case, the speed limit function will be set in the engine control unit, but when the engine control unit receives the control command from the transmission control unit, it performs control to match the engine speed to the request, In order to check the engaged / disengaged state of the clutch and the shift position of the transmission, it is not possible to manually control the shift of the vehicle manually (during manual shift operation by the driver). It is possible that rotation adjustment cannot be performed. At least, at the time of shifting by a manual operation of the driver, the engine speed cannot be increased beyond the maximum speed of the vehicle speed limit.
[0007]
An object of the present invention is to provide an effective means for solving such a problem.
[0008]
[Means for Solving the Problems]
The first invention is
Engine control means for controlling engine rotation / engine torque according to the accelerator opening during non-shifting, and engine rotation / engine torque according to control commands for automatic shifting during shifting;
Transmission control means for controlling the engagement / disengagement of the clutch and the gear shift of the transmission so as to perform the automatic shift to the target stage according to the driving state;
Communication means for exchanging control commands between them,
Means for manually manually controlling the on / off of the clutch, the gear shift of the transmission, and the accelerator opening of the engine;
In an automatic transmission vehicle comprising:
Means for controlling the engine speed so that the vehicle speed does not exceed the limit value;
Means for executing a control command from the transmission control means in preference to a vehicle speed limit during a shift receiving a control command from the transmission control means;
Is set in the engine control means.
[0009]
The second invention is
Engine control means for controlling engine rotation / engine torque according to the accelerator opening during non-shifting, and engine rotation / engine torque according to control commands for automatic shifting during shifting;
Transmission control means for controlling the engagement / disengagement of the clutch and the gear shift of the transmission so as to perform the automatic shift to the target stage according to the driving state;
Communication means for exchanging control commands between them,
Means for manually manually controlling the on / off of the clutch, the gear shift of the transmission, and the accelerator opening of the engine;
In an automatic transmission vehicle comprising:
Means for controlling the engine speed so that the vehicle speed does not exceed the limit value;
Means for releasing the vehicle speed limit during gear shifting without receiving a control command from the transmission control means;
Is set in the engine control means.
[0010]
The third invention is
Not receiving a control command from the transmission control means that the control command of the communication means does not exist or is invalid.
[0011]
The fourth invention is
Means for determining whether or not communication between the engine control means and the transmission control means is normal is provided. Not receiving a control command from the transmission control means means that the communication means is not normal.
[0012]
The fifth invention is
A clutch pedal detecting means for detecting that the clutch pedal is not depressed is provided, and it is assumed that the result of the detection by the clutch pedal detecting means is negative during a gear shift.
[0013]
【The invention's effect】
In the first aspect, during a shift receiving a control command (an engine control command required for automatic shifting) from the transmission control means, the engine control means performs engine control necessary for shifting in preference to vehicle speed limitation. Therefore, it is possible to increase the engine speed at the time of downshifting to be higher than the maximum speed limit of the vehicle speed.
[0014]
In the second aspect of the invention, the vehicle speed limit is released during a shift that does not receive a control command from the transmission control means, so that the engine speed can be increased to a value equal to or higher than the maximum speed limit by the driver's accelerator operation. It becomes.
[0015]
According to the third aspect, the vehicle speed limit is released during a shift in which the control command is not present or invalid from the transmission control means. Therefore, the driver operates the accelerator to increase the engine speed to the maximum speed of the vehicle speed limit or more. It is possible to do.
[0016]
According to the fourth aspect of the invention, the vehicle speed limit is released during a gear shift in which communication with the transmission control means is not normal, so that the engine speed can be increased to a value equal to or higher than the maximum speed limit by the driver's accelerator operation. It becomes.
[0017]
In the fifth aspect, if the communication with the transmission control means is not normal, and the detection result of the clutch pedal detection means becomes “No” (the clutch pedal is depressed), the vehicle speed restriction is released during that time. The driver's speed change operation makes it possible to increase the engine speed to a value equal to or higher than the maximum speed of the vehicle speed limit.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
In FIG. 1, 1 is a diesel engine, 2 is a friction clutch, 3 is a synchronous mesh transmission (transmission), and an output shaft of the transmission 3 is connected to a rear axle via a propeller shaft (not shown). An electronic governor device 1A for controlling the fuel injection amount to the engine fuel injection pump, a clutch booster 2A for driving the clutch 2 to connect and disconnect the clutch (an automatic control system and a manual control system are provided in the circuit configuration), and a gear shift for driving the transmission 23 to the gear shift. A unit 3A is provided. 27 is a supply / exhaust valve of the clutch booster 2.
[0019]
Engine speed sensor 29 for detecting engine speed, accelerator position sensor 28 for detecting the amount of depression of accelerator pedal 7 (required amount of accelerator position), stroke position of clutch 2 as detection means necessary for vehicle shift control. , A shift position sensor for detecting a shift position of the transmission 3 (built-in to the gear shift unit 3A), a vehicle speed sensor 21 for detecting a rotation speed from an output shaft of the transmission 3, and a main shaft of the transmission 3. And a gear rotation sensor 23 that detects the rotation speed of the main gear that idles.
[0020]
In order to switch between manual control and automatic control of the clutch 2, a clutch engagement switch 24 for detecting the initial position of the clutch pedal (the connection state of the clutch 2) and a clutch disconnection switch 25 for detecting the depression position (disconnection state of the clutch 2). And are provided. A shift lever unit 4 is provided in a cab as a shift instructing means of the transmission 3, and outputs a shift position signal (shift instructing signal) of the shift lever 4A. The display unit 13 displays the shift position of the transmission 3 in the driver's cab, a manual shift mode in which the shift of the vehicle is performed according to a shift operation of the driver, and an automatic shift mode in which the shift is automatically performed according to the driving state. A switch 31 (automatic speed change switch) for selection and a foot brake switch 26 for detecting depression of a brake pedal (not shown) are provided. 13A is an alarm buzzer.
[0021]
The transmission control unit 11 and the engine control unit 12 are responsible for the shift control. These units are connected by serial communication, so that shift information and control commands (control commands) can be exchanged. Normally, the engine control unit 12 controls the electronic governor device 1A so that the fuel injection pump supplies a fuel injection amount according to the detection signal of the accelerator opening sensor 28 and the detection signal of the engine rotation sensor 29, while automatically controlling the electronic governor device 1A. At the time of shifting, the electronic governor device 1A is controlled so as to obtain an engine rotation speed according to a control command from the transmission control unit 11.
[0022]
When the automatic shift switch 31 is ON, the transmission control unit 11 determines a target gear from a shift map (preset in a memory) based on a detection signal from the vehicle speed sensor 21 and a detection signal from the accelerator opening sensor 28, and shifts. When the detection signal (current gear) of the position sensor does not match the target gear, it is determined that the shift to the target gear is necessary, and the detection signal of the clutch stroke sensor 29 and the shift position are set so as to smoothly perform the gear shift to the target gear. While controlling the clutch booster 1A and the gear shift unit 3A based on the detection signal of the sensor, the detection signal of the gear rotation sensor 23, and the detection signal of the vehicle speed sensor 21, the engine control unit 12 Communicate to When the automatic shift switch 31 is OFF, the gear shift unit 3A is controlled based on the shift instruction signal of the shift lever unit 4 and the detection signal of the shift position sensor in order to perform a gear shift according to the shift lever operation of the shift lever unit 4. . The clutch booster 2A is switched to manual control by depressing a clutch pedal, and can be operated to a stroke corresponding to the depressed amount. This operation is communicated from the transmission control unit 11 to the engine control unit 12 as shift information.
[0023]
A vehicle speed limiting function is added to the engine control unit 12. The vehicle speed limiting function controls the electronic governor device 1A based on the detection signal of the vehicle speed sensor 21 so that the vehicle speed does not exceed the limit value (reduces the fuel injection) so that the rotation can be adjusted during gear shifting. The conditions for releasing the vehicle speed limit are set. FIG. 2 is a flowchart illustrating the vehicle speed limiting function. In S1, the detected value of the vehicle speed is compared with the vehicle speed limit to determine whether the vehicle speed is greater than the vehicle speed limit. When the determination in S1 is yes, the process proceeds to S2, while when the determination in S1 is no, there is no need to limit the vehicle speed, the process jumps to S8, and the normal control of the electronic governor device 1A (depending on the engine rotation and the accelerator opening) The control for supplying the fuel injection amount is performed.
[0024]
In S2, it is determined whether the serial communication between the transmission control unit 11 and the engine control unit 12 is normal. When the determination in S2 is yes, the process proceeds to S3, and when the determination in S2 is no, the process jumps to S7. In S7, it is determined whether or not the clutch engagement switch is OFF (whether or not the clutch pedal is depressed). If the determination in S7 is yes, it is determined that the driver has started the manual shift operation. Therefore, the process proceeds to S8, while if the determination in S7 is no, the process proceeds to S6.
[0025]
In S3, it is determined whether or not a shift is being performed (whether there is communication of shift information). If the determination in S3 is yes, the process proceeds to S4, while if the determination in S3 is no, the process jumps to S6, and the vehicle speed is limited based on the determination in S1. In S4, it is determined whether there is no (or invalid) engine control command. If the determination in S4 is yes, it is determined in S5 that the shift in S3 is performed by manual control, so that the vehicle speed restriction is released (the fuel injection amount reduction control is temporarily canceled). On the other hand, when the determination in S4 is no, it is determined that the automatic transmission is being performed during the shift in S3, and in S6, the engine control according to the control command from the transmission control unit 11 is prioritized over the vehicle speed limit control. Run.
[0026]
With such a configuration, the fuel injection amount is normally supplied in accordance with the accelerator opening and the engine speed within the range of the vehicle speed limit. When the vehicle speed limit is exceeded, the fuel injection amount is reduced, and the engine speed is limited to the vehicle speed limit. Less than the maximum rotation of. When the automatic transmission is started during traveling, the engine speed, the on / off of the clutch 2, the disengagement and the engagement of the transmission 3 are controlled in accordance with a predetermined processing order, and the engine control unit 12 controls the transmission control. Since the engine control according to the control command from the unit 11 is executed prior to the control of the vehicle speed limitation, the shift operation to the target gear is also smoothly performed.
[0027]
When the manual shift is performed, the engine control unit 12 determines that the shift is being performed without a control command. If the vehicle speed is being limited, the limitation is released. As a result, the engine speed can be increased to a value equal to or higher than the maximum vehicle speed limit by operating the accelerator.
[0028]
If the communication between the transmission control unit 11 and the engine control unit 12 is impaired, it will not be determined whether or not a shift is in progress. However, the driver's depression of the clutch pedal cancels the vehicle speed limitation. The rotation of the engine can be adjusted in accordance with the shift, and the running of the vehicle can be continued without any trouble.
[0029]
In FIG. 2, the processing from S1 to S5 is a means for releasing the vehicle speed restriction during a shift without receiving (or invalid) a control command from the transmission control unit 11, and the processing from S1 to S4 to S6 is a transmission control unit. Means for executing the control command prior to the vehicle speed limit during the shift receiving the control command from S11, the processing from S1, S2, S7 to S8 is performed when the communication is not normal and the clutch pedal is depressed. Means for releasing the restriction.
[0030]
By setting such control, the vehicle speed limiting function of the automatic transmission vehicle (including the function of temporarily canceling the vehicle speed limitation during gear shifting) is inexpensive without using new detecting means by using existing detecting means. It can be realized in
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a system representing an embodiment of the present invention.
FIG. 2 is a flowchart illustrating control contents of an engine control unit.
[Explanation of symbols]
1A Electronic governor device 2A Clutch booster 3A Gear shift unit 4 Shift lever unit 11 Transmission control unit 12 Engine control unit 21 Vehicle speed sensor 22 Clutch stroke sensor 23 Gear rotation sensor 24 Clutch contact switch 28 Accelerator opening sensor 29 Engine rotation sensor 31 Automatic transmission switch

Claims (5)

Engine control means for controlling engine rotation / engine torque according to the accelerator opening during non-shifting, and engine rotation / engine torque according to control commands for automatic shifting during shifting;
Transmission control means for controlling the engagement / disengagement of the clutch and the gear shift of the transmission so as to perform the automatic shift to the target stage according to the driving state;
Communication means for exchanging control commands between them,
Means for manually manually controlling the on / off of the clutch, the gear shift of the transmission, and the accelerator opening of the engine;
In an automatic transmission vehicle comprising:
Means for controlling the engine speed so that the vehicle speed does not exceed the limit value;
Means for executing a control command from the transmission control means in preference to a vehicle speed limit during a shift receiving a control command from the transmission control means;
A speed limiter for an automatic transmission vehicle, wherein the speed limiter is set as engine control means. Engine control means for controlling engine rotation / engine torque according to the accelerator opening during non-shifting, and engine rotation / engine torque according to control commands for automatic shifting during shifting;
Transmission control means for controlling the engagement / disengagement of the clutch and the gear shift of the transmission so as to perform the automatic shift to the target stage according to the driving state;
Communication means for exchanging control commands between them,
Means for manually manually controlling the on / off of the clutch, the gear shift of the transmission, and the accelerator opening of the engine;
In an automatic transmission vehicle comprising:
Means for controlling the engine speed so that the vehicle speed does not exceed the limit value;
Means for releasing the vehicle speed limit during gear shifting without receiving a control command from the transmission control means;
A speed limiter for an automatic transmission vehicle, wherein the speed limiter is set as engine control means. 3. The vehicle speed limiting device according to claim 2, wherein not receiving a control command from the transmission control means means that a control command of the communication means does not exist or is invalid. 3. A system according to claim 2, further comprising means for determining whether communication between the engine control means and the transmission control means is normal, and not receiving a control command from the transmission control means that the communication means is not normal. The speed limiting device as described. 5. The speed limiting device according to claim 4, further comprising a clutch pedal detecting means for detecting that the clutch pedal is not depressed, and wherein the result of the detection by the clutch pedal detecting means is negative during a shift.

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