JPS6349537A - Speed control device - Google Patents

Abstract

PURPOSE:To reduce the number of speed changes during traveling by selectively controlling an automatic speed change control means and a constant speed traveling control means, and releasing (connecting) a lock-up clutch when the deviation of vehicle speed is large (small), at the time of the controlled condition of both control means. CONSTITUTION:The electronic control means of a speed control device has a microcomputer CPU, which has an automatic speed change control means for making a speed change control as a speed change stage corresponding to the output of a vehicle speed or engine speed and an engine load or throttle opening, and a constant speed traveling control means for controlling so that a defined set vehicle speed is maintained by controlling the throttle opening. In this case, the selective control between the automatic speed change control means and the constant speed traveling control means is made and, when both control means are in controlled conditions, a lock-up clutch is released (connected) when the deviation of vehicle speed is large (small). Thereby, the number of times of down-shift during the constant speed traveling control can be reduced, relieving a speed change shock.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to the functions of an automatic speed change control means such as an electronically controlled two-way four-speed automatic transmission with overdrive, and the constant speed control device and the like. This relates to a speed control device for an automobile that has the function of a speed control means, and in particular, the function of an automatic transmission control device and the function of a constant speed control device, which were controlled independently, is
Common control times.

This article relates to a speed control device for road control.

[Prior Art] For example, in the drive (D) range, the shift control of a vehicle equipped with a conventional automatic shift control device uses a shift map that stores a predetermined shift line based on the vehicle speed and throttle opening at that time; For example, the optimum gear position is selected and controlled in accordance with a shift map in which the shift lines shown in FIG. 14 are stored.

In addition, the lock-up function of a torque converter with a lock-up clutch in an automatic transmission connects the lock-up clutch when the vehicle speed exceeds a certain speed in a certain gear position, for example, 3rd gear or overdrive (4th gear). hand,
The output shaft of the automatic transmission is directly connected to the engine output shaft in the lock-up clutch state (hereinafter, this state is referred to as "lock-up").
In other cases, the lock-up clutch state is released, that is, the lock-up is released, and the input shaft of the automatic transmission is connected to the engine output shaft.

In this way, by releasing the lock-up and making use of the torque converter's function, when the car starts, suddenly accelerates, shifts, etc., the gears are changed according to the load, resulting in smooth starting and smooth acceleration. This enables smooth gear changes and prevents the engine from knocking or stopping.

However, when the load is small and the engine speed is high, the torque converter is locked up to prevent power loss due to torque converter slip and a reduction in fuel efficiency.

The constant speed traveling device sets the desired traveling vehicle speed to the set vehicle speed and controls the opening degree of the throttle valve to maintain this set vehicle speed, and performs control according to the road conditions.

[Problems to be Solved by the Invention] However, in automobiles equipped with the above-mentioned conventional independent automatic transmission control device and constant speed driving device, even if the vehicle speed is maintained constant while driving at a constant speed, The automatic transmission control device may detect the state of the throttle opening that has been changed due to this change, and the gear position of the automatic transmission may change.

For example, when traveling at a constant speed of 80 km/h on an uneven road, the throttle opening is 80% on the uphill road and 40% on the downhill road. At this time, if the shift map shown in Fig. 14 is used, the gear position selectively controlled by the automatic transmission control device is downshifted from OD (overdrive) to 3rd gear on the uphill road, and 3rd gear on the downhill road. is upshifted from to OD.

In this way, when the automatic transmission control device shifts up or down, a slight shift shock is transmitted to the vehicle body, and it is predicted that the ride comfort may be poor. In particular, if we assume that the road has many ups and downs and a hunting situation occurs where downshifts and upshifts are repeated,
There arises a need to consider passenger comfort.

Therefore, the constant speed driving function has an automatic gear shifting function while driving at a constant speed. Japanese Unexamined Patent Publication No. 60-237258 discloses a technology that prohibits shifting of the gear position by not having the gear position, thereby preventing the shock caused by changing the gear position while driving at a constant speed.

Furthermore, Japanese Patent Laid-Open No. 56-39354 discloses a technique for releasing the lock-up of a torque converter during gear shifting.

However, even if the lock-up of the torque converter is released when changing gears during constant speed driving control, it does not reduce the number of downshifts. As a result, the control of the throttle opening became a factor that caused the automatic transmission control device to change gears, and the number of times the automatic transmission control device changed gears increased, causing problems with shocks and the number of times they changed gears.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a speed control device that can reduce the number of downshifts that occur during constant speed driving control during automatic speed change control. be.

[Means for Solving the Problems] The speed control device of the present invention controls an automatic transmission with a built-in torque converter with a lock-up clutch to change gears according to vehicle speed or rotational speed output, engine load, or throttle opening. an automatic shift control means; a constant speed running control means for controlling the throttle opening to maintain a predetermined set vehicle speed; When the constant speed running control means is in the control state, the vehicle is equipped with electronic control means for releasing the lock-up clutch when the vehicle speed deviation becomes large and for enabling the lock-up clutch when the vehicle speed deviation becomes small. .

[Function] The present invention includes an automatic transmission control means that controls an automatic transmission with a built-in torque converter with a lock-up clutch to change gears according to vehicle speed or rotational speed output, engine load, or throttle opening; A constant speed running control means for controlling to maintain a predetermined set vehicle speed, and an electronic control means for selectively controlling the automatic shift control means and the constant speed running control means, and the electronic control means automatically shifts the speed. While the control means and constant speed running control means are operating, the lock-up clutch is released when the vehicle speed deviation becomes large, the torque converter function compensates for the insufficient torque, and the lock-up clutch is enabled when the vehicle speed deviation becomes small. As a state, it is locked up depending on the conditions. Therefore, in the event of insufficient driving force within the range where the torque converter function can compensate for the insufficient torque, the driving force can be compensated for without downshifting, and when the automatic shift control means and constant speed driving control means are in operation. The number of gear changes can be reduced.

[Embodiment] FIG. 1 is a control circuit diagram configuring electronic control means of a speed control device according to an embodiment of the present invention.

In the figure, the microcomputer CPU is a microcomputer,
It is also called a one-chip microcomputer or microprocessor, and is composed of a control section, an arithmetic section, and registers. Battery B
E denotes a DC power supply for use in the vehicle, and a constant voltage power supply circuit CON supplies power to the microcomputer CPtJ, input interface circuit IP, and output interface circuit OP, and becomes operational when the ignition switch IG is turned on. The speed sensor SP1 is a reed switch configured by forming a pair with a magnet connected to a speedometer cable, and obtains a pulse number proportional to speed. The speed sensor SP2 is a reed switch configured by forming a pair with a magnet that rotates integrally with the output shaft attached to the output shaft of the automatic transmission, and obtains a pulse number proportional to the rotation speed of the output shaft. The reed switch of Speed Sen'J-3P1 is diode D1.
and is connected to the base of the transistor Q1 via the resistor R1. When the reed switch of the speed sensor SP1 is on, the transistor Q1 is turned on and a voltage is applied to the terminal of the resistor R3, and the input port P1 of the microcomputer CPU is It becomes “H”. Further, when the reed switch of the speed sensor SP1 is turned off, the transistor Q1 is turned off by the resistor R2, the terminal of the resistor R3 becomes the ground potential, and the panono port P1 of the microcomputer CPU becomes "L". And the speed sensor +
: The reed switch of J-3P2 is connected to the base of the transistor Q2 via the resistor R5, and when the reed switch of the speed sensor SP2 is turned on, the transistor Q2 is turned on and a voltage is applied to the terminal of the resistor R7. The input port P2 of the computer CPU is “Hpt
becomes. Furthermore, when the reed switch of speed sensor SP2 is off, transistor Q2 is turned off by resistor R4 and resistor R6, the terminal of resistor R7 becomes ground potential, and input port P2 of microcomputer CPU is "
It becomes L ml.

The shift position switch SPS is a switch that detects the position of the shift lever. N indicates that the shift lever is in the neutral range, D indicates that the shift lever is in the drive range, 2 indicates that the shift lever is in the 2nd gear range, and L indicates that the shift lever is in the 1st gear range. The detection switch detects the neutral range detection switch 5PS-N and the 2nd speed range detection switch 5PS-N.
PS-2 and 1st speed range detection switch 5PS-1 are connected to pull-down resistors R8, R9, and RIO, respectively, and when the shift levers are not in their respective positions, the outputs of buffer amplifiers DRI, DR2, and DR3 are “L”. l?, and input port P3゜R4 of microcomputer CPU.
, R5 becomes "LH". Also, the shift lever stops at the predetermined position and the neutral range detection switch 5PS
- When the 2nd speed range detection switch 5PS-2 and 3rd speed range detection switch 5PS-3 are turned on, the battery power supply B
E becomes the input of the buffer 7 amplifiers DRI, DR2, and DR3, the output thereof becomes "HIF", and the input ports P3, R4, and R5 of the microcomputer CPU become "H".

The mode switch MS is a switch that switches to the automatic shift control mode at the E and P positions, and to the automatic shift constant speed traveling control mode at the A position. At position P, battery BE connects to resistor R11.
becomes the input of the buffer 7 amplifier DR4 via the resistor R12, and its output becomes "'H", and the input port P6 of the microcomputer CPU becomes "Het".At the P position, the battery BE becomes the input of the buffer 7 amplifier DR5 via the resistor R12. The output becomes HIF, and the microcomputer CP
The input port P7 of U becomes "Hpe. At the P position and A position where the mode switch MS is not in the stopped state, it becomes the input of the buffer 7 amplifier DR4 or DR5 by the pull-down resistor R13 or pull-down resistor R14, and its output becomes "L'', and the input port P6 or R7 of the microcomputer CPtJ becomes "L".

The throttle opening sensor SS detects the depression of the accelerator pedal or the throttle opening, and in this embodiment,
The throttle opening is determined by the 3-bit contacts Ll and L2 on the code board.
．． L3 “H (high level)”, “”L (low level)
'' outputs the throttle speed in stages 0 to 7 as a signal.The contact IDL supplies a signal to detect that the foot is released from the throttle.In other words, the 3-bit contact Ll on the code board , 12.13 are in the on state, they become inputs to buffer amplifiers DRf3, DR7, DR8 via series resistors R15, RIB, R17, and their output becomes "U PI", which is input to the microcomputer CP.
Input ports P8, R9, and PIO of U are 141 F#.

Also, the 3-bit contacts Ll and L2 on the code board.

When L3 is off, pull-up resistor R18゜R19
, R20, the inputs of the buffer 7 amplifiers DR6, DR7, and DR8 are set to “H” via the series resistors R15, R16, and R17.
'', the input port P of the microcomputer CPU
8, R9, and Plo become ""Hpt.

When the common contact IDL is on, the base current of the transistor Q3 flows through the diode D2 and the resistor R21,
Transistor Q3 is turned on, voltage is applied to the terminal of resistor R23, and the input port P11 of the microcomputer CPU becomes "Hto."Furthermore, when the common contact IDL is turned off, transistor Q3 is turned off by resistor R22, and the terminal of resistor R23 is turned off. becomes the ground potential, and the input port P11 of the microcomputer CPU becomes "L".

The voltage of the battery BE is connected to the fuse F at the input port P12.
It is applied via U, and resistor R24 and resistor R25.
As a result, the transistor Q4 is turned on, and the input port P12 of the microcomputer CPU is set to "L".

When the fuse FU is blown due to an abnormality in the brake system or the like, the transistor Q4 is turned off and the input port P12 of the microcomputer CPU is set to Het.

The brake switch BS operates when the brake is depressed, and at this time lights up the brake lamp BL. That is, when the brake is depressed and the brake switch BS is turned on, the voltage of the battery BE is turned on by the resistor R27 and the resistor R28, and the transistor Q5 is turned on.
Set the input port P13 of the microcomputer CPU to “L”.
IF. Then, when the brake pedal pressure is released and the brake switch 83 is turned off, the transistor Q
5 is turned off, and the input port P13 of the microcomputer CPU is set to "HIt".

Parking switch PK is a detection switch that detects that the shift lever is in the parking position.
This is a switch that turns on when the vehicle is in the parking position.

When the parking switch PK is turned on, the transistor Q6 is turned on by the resistor R30, resistor R31, resistor R32, and diode D3, and a voltage drop occurs across the resistor R33, causing the input port P14 of the microcomputer CPU to become "H".
It becomes u. Further, when the parking switch PK is turned off, the transistor Q6 is turned off, and the input port P14 of the microcomputer CPU is set to L'' by the resistor R33.

The set switch SP is used to set the constant speed traveling control means to a predetermined speed, and when the set switch SP is turned on, the current traveling speed is set as the constant traveling speed. That is, when the set switch SP is on, the base current of the transistor Q7 flows through the diode D4 and the resistor R34, the transistor Q7 is turned on, a voltage is applied to the terminal of the resistor R3B, and the input port P15 of the microcomputer CPU is " When the set switch SP is off, the transistor Q7 is turned off by the resistor R35, the terminal of the resistor R36 becomes the ground potential, and the input port P15 of the microcomputer CPU becomes "L".

The resume switch R3 is used to control constant speed driving again at the set speed after the set speed is set to set the constant speed driving control means to a predetermined speed. By turning on R3, the vehicle enters constant speed driving control again. That is, when the resume switch R3 is turned on, the base current of the transistor Q8 flows through the diode D5 and the resistor R37, the transistor Q8 is turned on, and a voltage is applied to the terminal of the resistor R39, and the input port P16 of the microcomputer CPU is turned on. H+
It becomes 1. Further, when the resume switch R3 is turned off, the transistor Q8 is turned off by the resistor R38, the terminal of the resistor R39 becomes the ground potential, and the input port P16 of the microcomputer CPU becomes #L $1.

The vacuum switch (S) detects the pressure state of a surge tank that stores negative pressure that controls the constant speed running control means, and operates when the pressure decreases. That is, the negative pressure in the vacuum tank controlled by a release valve RV and a control valve 'CV, which will be described later, is supplied by a vacuum pump VP driven by a vacuum pump motor M, and the supply pressure is supplied by a vacuum switch VS.
detected by. When the vacuum switch S is turned on, the base current of the transistor Q9 flows through the diode D6 and the resistor R40, the transistor Q9 is turned on, a voltage is applied to the terminal of the resistor R42, and the input port P17 of the microcomputer CPU is "H". ”.

Also, when the vacuum switch ■S is off, the resistor R4
1, the transistor Q9 is turned off, the terminal of the resistor R42 becomes ground potential, and the microcomputer CPU
The input port P17 becomes "LT1".

The constant-speed running main switch ADS has a constant-speed running function when its contact is ON, and cancels the constant-speed running function when its contact is on the F side. Constant speed driving main switch ADS is contact O
When on the N side, the base current of transistor QIO flows through diode D7 and resistor R43, transistor QIO is turned on, voltage is applied to the terminal of resistor R45, and input port P18 of microcomputer CPU becomes HIF.

Also, when the constant speed running main switch ADS is on the contact point F side, the transistor QIO is switched to the contact point F side by the resistor R44.
Therefore, the terminal of the resistor R45 becomes the ground potential, and the input port P18 of the microcomputer CPU becomes OP.

The output side of the microcomputer CPU is connected as follows.

The shift solenoid SL1 and the shift solenoid SL2 are actuators that determine the gear stage of the automatic transmission, and the shift solenoid SL1 and the shift solenoid SL2 are energized and de-energized to shift from 1st speed to OD (overdrive).
It allows for 4-speed shifting. The following table shows an example.

Further, the lock-up solenoid SL3 is an actuator that determines the gear stage of the automatic transmission, and performs lock-up control by energizing and de-energizing the actuator. When the lock-up solenoid SL3 is energized, it locks up,
Release lock-up in de-energized state.

When the output port P21 and the output port P22 of the microcomputer CPU are LIT and "H", the outputs of the buffer amplifiers DR11 and DR12 are L" and "HII".
Therefore, transistor Q21 turns on, and resistor R51
, transistor Q21, and shift solenoid SLI are energized. In addition, output port P21 and output port P
When Q22 is at 1" and "Lee," the outputs of buffer amplifiers DR11 and DR12 are "HIF" and "L," and the transistor Q21 is off and the shift solenoid SL is turned off.
1 is in a de-energized state.

Similarly, the output port P2 of the microcomputer CPU
When output port P23 and output port P24 are "H" and "H", shift solenoid SL2 is energized, and when output port P23 and output port P24 are "H" and L It, shift solenoid SL2 is de-energized. . Furthermore, when the output port P25 and the output port P2B of the microcomputer CPU are "L tt" and "H99," the lock-up solenoid SL3 is energized, and the output port P25 and the output port P2B are "H" and "L 9%."
At this time, the lock-up solenoid SL3 is de-energized. Note that the resistor R52, the transistor Q22, the resistor R53, and the transistor Q23 constitute a switching circuit, and the diode [)11. [)12. D13 is a flywheel diode. Further, buffer amplifiers DR11 to DR20 function as drive circuits.

The release valve RV and the control valve CV are used to determine the degree of opening and closing of the throttle valve using a negative pressure actuator.During constant speed driving control, the set vehicle speed and the vehicle speed at that time are compared, and the above-mentioned When the solenoid is energized, the control valve C2 forms a path for sending negative pressure from the surge tank to the negative pressure actuator, and when the solenoid is not energized, it blocks the path. Further, the release valve RV discharges the negative pressure of the negative pressure actuator to the atmosphere when the solenoid is in a non-energized state, and blocks the path when the solenoid is in an energized state.

That is, the output port p27 of the microcomputer CPU
When "Hto" and output port P29 are "L", transistor Q24 and transistor 02B are turned on, and the solenoid of release valve RV is energized.

Output port P27 is 411 tt and output port P29
When "Htt" is turned off, transistor Q24 and transistor 026 are turned off, and the solenoid of release valve RV is de-energized. Output port P2B of microcomputer CPU is "H" and output port P29 is "L".
When It, transistor Q25 and transistor Q
2B is turned on, and the solenoid of the control valve CV is energized. When output port P28 is “L” and output port P29 is “HIT”, transistor Q25
Then, transistor Q2B is turned off, and the solenoid of control valve RV is de-energized.

Hey, release valve RV and control valve CV
The negative pressure in the surge tank controlled by is supplied by a vacuum pump, and the vacuum pump VP is driven by a vacuum pump motor M. In the vacuum pump motor M, when the output port P30 of the microcomputer CPU is L11, the output of the buffer amplifier DR20 is "Ltp", and the transistor Q27 is turned on, so that the vacuum pump motor M is in the driving state. At this time, the output of the buffer 7 amplifier DR20 becomes "Hpp", and the transistor Q27 is turned off to be in a stopped state.

The control circuit of the speed control device of this embodiment configured as described above is controlled as follows.

2 to 6 are general flowcharts for controlling the speed control device of this embodiment.

First, in step G1, the memory and output ports necessary for executing this control are initialized. In step G2, the status of each input port is read. Then, it determines whether the current control state is constant speed driving control during automatic speed change control (automatic speed constant speed driving control), and executes a routine that determines the conditions for entering automatic speed change constant speed driving control. do.

In step G3, it is determined whether the constant speed driving main switch ADS is on or off, and when the constant speed driving main switch ADS is on in step G3, the constant speed driving set flag is set (“H”) in step G4. ). When the constant speed running set flag is set, it is determined in step G5 whether the gear is currently being changed. When the gear is not being shifted in step G5, constant speed driving i1+L (
Set the ECT-A/D (automatic shift constant speed driving control) flag to perform iT. In step G7, it is determined whether the constant speed driving cancel flag for canceling the constant speed driving control is set, and when the constant speed driving cancel flag is lowered ("L") in step G7, this determination routine is exited. Also, in step G3, the constant speed driving main switch AD
When it is determined that S is in the off state, step G
If it is further determined in step G8 that the gear is currently being shifted, or if it is determined in step G8 that the gear is not currently being shifted, the ECT-A/D flag is lowered in step G9 and this determination routine is exited. . In other words, if the gear is currently being shifted, that state will continue and the ECT-A/D will be activated when the gear shift is completed.
Raise and lower flags.

Next, the ECT-A/D flag is checked to select a speed change map for automatic speed constant speed traveling control and automatic speed change control. In addition, when controlling the driver's accelerator operation, that is, when requesting a kickdown by rapidly opening the throttle, automatic shifting control is activated even if the conditions for automatic shifting constant speed driving control are met. .

First, in step G10, the speed of the currently running vehicle is calculated.

In step G11, it is determined whether the ECT-A/D flag is set, and when the ECT-A/D flag is not set, in step G21, a shift map for automatic shift used only during automatic shift control as shown in FIG. and step G22.
Select the automatic shift lock-up map shown in FIG. 10, which is used only during automatic shift control. Then, in step G23, the gear position and lock-up clutch state corresponding to the current vehicle speed are searched from the automatic transmission shift map and the automatic transmission lock-up map, and in step G24, the automatic transmission shift map and the automatic transmission lock-up map are searched for. Based on the shift lockup map data, it is determined whether the gear position and lockup clutch state are appropriate according to the current vehicle speed.

When the ECT-A/D flag is set in step G11, it is determined in step G12 whether the accelerator operation flag is set. Normally, at the beginning of this control, the accelerator operation flag is not set, so in step G13, the accelerator operation is detected, that is, the variable of the throttle opening sensor SS is detected. If a variable of the predetermined throttle opening sensor SS is detected in step G14, step G14
The process moves to step G15, and an accelerator operation flag is set. Furthermore, since a relatively long timer is used during the automatic shift-constant speed running control in step G16, the upshift prohibition timer Tim■ set for the time limit is cleared. Then, in step 'G21, a shift map for automatic shift used only during automatic shift control shown in FIG. 9 is selected, and in step G22, a lockup map for automatic shift shown in FIG. 10 used only during automatic shift control is selected. Select.

Furthermore, in step G23, the gear position and lock-up clutch state corresponding to the current vehicle speed are searched from the automatic transmission shift map and the automatic transmission lockup map, and in step G24, the automatic transmission shift map and the automatic transmission lockup map are searched. Based on the shift lockup map data, it is determined whether the gear position and lockup clutch state are appropriate according to the current vehicle speed.

Further, if it is determined in step G12 that the accelerator operation flag is set, and if it is determined in step G17 that the vehicle speed deviation is smaller than a predetermined threshold, the accelerator operation flag is lowered in step 018, and the accelerator operation flag is set in step G19. 11
In step G20, the selection of the automatic shift map for constant speed travel used during the automatic shift constant speed travel control shown in the figure is selected as the lockup map for automatic shift constant speed travel used during the automatic speed change constant speed travel control shown in FIG. Then, in step G23, from the automatic gear shift map for constant speed running and the lockup map for automatic gear constant speed drive,
The gear position and lock-up clutch state corresponding to the current vehicle speed are checked, and in step G24, the current speed is determined from the data of the automatic transmission constant speed driving shift map and the automatic transmission constant speed driving lockup map. It is determined whether the gear position and lock-up clutch state are appropriate depending on the vehicle speed. Incidentally, this routine also performs the processing of the routine from step G19 to step G24 even if the accelerator operation is detected in step G13 and the detected variable is determined to be less than the threshold of the predetermined throttle opening sensor SS in step G14. Become.

Then, if it is determined in step G12 that the accelerator operation flag is set, and furthermore, if it is determined in step G17 that the vehicle speed deviation is larger than a predetermined threshold value, the routine from step G21 to step G24 is executed. .

That is, when the driver operates the accelerator due to a kickdown or the like, an accelerator operation flag is set in step G15, and then the flag is set only during automatic shift control in step G21 until the vehicle speed deviation becomes small in step G17. Select the shift map for automatic shift to be used in step G22.
Select the lock-up map for automatic gear shift to be used only during automatic gear shift control. Then, in step G17, when the vehicle speed deviation becomes smaller, in step G19, the selection of the automatic speed change map for constant speed driving to be used during automatic speed constant speed driving control is performed, and in step G20, the selection of the automatic speed change map for use in automatic speed changing constant speed driving control is performed. Select the lock-up map for constant speed driving.

Next, control of the lock-up clutch during constant speed driving control is started.

Checking the state of the ECT-A/D flag in step G30,
It is determined whether the automatic shift is under constant speed driving control, and when the constant speed driving control is being performed, it is determined in step G31 whether the vehicle speed deviation is greater than or equal to a predetermined threshold.When the vehicle speed deviation is greater than or equal to the predetermined threshold, automatic The transmission's torque converter function releases lockup to obtain torque. That is,
During constant speed running control, the lock-up of the torque converter is released when a predetermined vehicle speed deviation becomes large regardless of the shift line. In step G33, a lock-up prohibition timer Tim[ that prohibits lock-up is set to 5 seconds and started.

Further, when it is determined in step G30 that constant speed driving control is being performed, and it is determined in step G31 that the vehicle speed deviation is smaller than a predetermined threshold value, it is determined in step G34 whether the vehicle speed deviation is small enough to maintain the lock-up state, When the vehicle speed deviation is small, lockup is permitted in step G35.

Next, the actual gear shifting operation begins, and various timers are set to obtain the timing for gear shifting.

If it is determined in step G36 that a shift is necessary as a result of the processing in steps G23 and G24, the gear position to be shifted is set in step G38. Check whether the ECT-A/D flag is set in step G39, that is, whether the automatic shift constant speed driving control is being performed.
The state of the flag is determined, and when the ECT-A/D flag is not set, the set time limits of various shift timers during automatic shift control are searched in step G40, and the time up of the upshift delay timer T 1ml1l is determined in step G41. do. Upshift delay timer T 1m1II
has timed up, and when it is determined in step G42 that the full shift timers T1 to T5 or the shift timer T1 are not operating at their initial values, the shift timers T1 to T5 are started in step G43. Also, step G
If it is determined in step G36 that there is no need for a shift as a result of the processing in step G23 and step G24, an upshift delay flag that delays the upshift shift operation for a certain period of time is lowered after determining an upshift in step G37. Then, in step G44, it is determined whether the set time limits of the shift timers T1 to T5 have timed up, and when the set time limits of the shift timers 94711 to 94711 to T5 have timed up, in step G45, it is determined whether the set time limits of the upshift prohibition timer TimI have timed up, When the upshift prohibition timer TimI has exceeded the set time limit, step G4 is further executed.
In step G46, it is determined whether an upshift is being performed, and in step G47, it is determined that an upshift is prohibited based on the upshift prohibition flag. If the upshift prohibition flag is not set, the gear position and Release the lock-up clutch condition. Also, if the amplifier is not being shifted in step G46, step G
At step 48, the gear position and lock-up clutch status are output.

However, in step G44, when the set time limits of the shift timers T1 to T5 have not yet elapsed, and in step G45, before the set time limits of the upshift prohibition timer TimI have elapsed, it is determined that an upshift is in progress in step G46, and in step G47
When the upshift prohibition flag is set, the gear position and lock-up clutch status are not output.

Furthermore, if it is determined in step G39 that the ECT-A/D flag is set, and furthermore, it is determined that the accelerator operation flag is set in step G49, the driver's kickdown operation is performed by rapidly opening the throttle. Since the request is assumed, automatic shift control is performed, and the routine processing from step G40 to step G4B is performed.

When it is determined in step G39 that the ECT-A/D flag is set and the accelerator operation flag is lowered in step G49, it is determined in step G50 whether the gear shift is an upshift or a downshift.

In the case of a downshift, a downshift timer for constant speed running is searched for in step G60, and an upshift prohibition timer Tim■ is set and started in step G61. Lower the upshift delay flag in step G62,
The routine processing from step G41 to step 048 is performed.

If the gear shift is determined to be an upshift in step G50, the upshift timer for constant speed driving is searched in step G51, and after the upshift determination is made in step G52, an upshift delay flag is set to delay the upshift for a certain period of time. determine whether When the upshift delay flag is not set, set 5 seconds to the upshift delay timer T 1ml in step G53.
Then, in step G54, the upshift delay timer T
Start with 1ml.

Furthermore, in step G55, the current driving force TN is calculated, in step G56, the maximum driving force TN+1 after upshifting is calculated, and in step G57, the calculated current driving force T is calculated.
N and the maximum driving force T N+1 after upshifting are compared, and if TN < TN+1, an upshift prohibition flag is set in step G58 to prohibit upshifting.

When TN<TN+1, the upshift prohibition flag is lowered in step G59 to cancel the upshift prohibition. After the processing in step 058 or step G59, the routine processing from step G41 to step G48 is performed.

Note that the driving force is Driving force = engine torque x gear ratio x reduction ratio ×Power transmission efficiency X torque converter torque conversion ratio ×loss correction coefficient It is expressed as

Next, throttle opening control is started to reduce shift shock when a shift occurs during constant speed running control. At the end of this process, the state of mode switching of the automatic transmission control means is checked.

It is determined in step G'70 whether the accelerator operation flag is set, and when the accelerator operation flag is not set, it is determined in step G71 whether the ECT-A/D flag is set, and the ECT-A/D flag is set. At this time, it is further determined in step G72 whether or not gears are being changed. That is, if the accelerator operation flag is set after entering the automatic speed change constant speed driving control, it is ignored that a kickdown request has been issued. If the gear is currently being shifted, it is determined in step G73 whether a throttle hold flag is set to reduce the opening of the throttle during the gear shift. If the throttle hold flag is not set, step G74 sets the throttle hold flag, step G75 calculates the current driving force TN, and step G76 calculates the post-shift driving force closest to the current drive horn TN. Throttle opening θ
N@calculate. Then, in step G77, it is confirmed that this is necessary before the set time limit of the shift timer has elapsed, that is, during the shift period, the throttle opening θN is set in step G78, and the state of the throttle opening θN is maintained in step G79. Therefore, the duty ratio of the negative pressure actuator of the constant speed traveling control means is controlled. Then, in step G96, the resume switch R8 is turned off, in step G97, the brake switch BS and the parking switch PK are turned off, and in step G9
8, it is confirmed that it is in the D range, and furthermore, step G
99, the minimum set travel speed for constant speed driving is 40 Klll/h.
If it is confirmed that the following is not the case, step G2
Return to the routine processing from.

If it is not determined in step G72 that the gear is being shifted, it is determined in step G90 whether the constant speed running main switch ADS is on or off, and if the constant speed running main switch ADS is on, the current constant speed running speed is determined in step G91. Determine whether it is set.

When constant speed running set switch SP or resume switch R3 is turned on and the set vehicle speed is set,
In step G92, lower the constant speed driving cancel flag,
Also, set the constant speed running set flag. Step G93
When it is determined that the ECT-A/D flag is set, constant speed running control is entered in step G94. Then, in step G95, the throttle hold flag is lowered, and the routine from step G96 to step G100 is executed.

Note that at the initial stage when the constant speed running set flag is set in step G92, the ECT-A/D flag is not set in step G93, so the steps from step 096 to step G1
00 routine processing is performed. Further, when the constant speed driving main switch ADS is turned off in step G90, the constant speed driving cancel flag is set in step G101, and the constant speed driving set flag is lowered, the routine processing from step G99 to step G100 is also performed. .

When the resume switch R8 is turned on in step G96, the constant speed driving cancel flag is lowered in step G102, and it is confirmed that the brake switch BS and parking switch PK are turned on in step G97, or that the vehicle is not in the D range in step G98. If so, a constant speed running cancel flag is set in step G103. Then, in step G99, the lowest setting traveling speed for constant speed traveling is 4.
If it is determined that the speed is 0 Km/h or less, a constant speed running cancel flag is set in step G100, and after the constant speed running set flag is lowered, the process returns to the routine from step G2.

Also, if it is determined in step G77 that the set time limit of the shift timer has not yet elapsed, steps G90 to G1
00 routine processing is performed.

That is, to enter automatic shift constant speed running control from automatic shift control, constant speed running main switch DS is switched in step G90.
is turned on, and when the constant speed running set switch SP or the resume switch R3 is turned on in step 91 and the set vehicle speed is set, the constant speed running set flag is set in step G92, and this is determined in step G4. However, when it is determined in step G5 that the shift timer has timed up, the ECT-A/D flag can be set in step G5. Then, in step G39, ECT-
The state of the A/D flag is judged, and when the ECT-A/D flag is set, the upshift timer for constant speed driving or the downshift timer for constant speed driving is selected. , determine whether the maximum driving force when upshifting is greater than or equal to the current driving force. Then, when it is confirmed in step 93 that the ECT-A/D flag is set, automatic speed change constant speed running control can be entered.

Conversely, to enter automatic shift control from automatic shift constant speed running control, resume switch R3 is turned off in step G96, brake switch BS or parking switch PK is turned on in step G97, and when the vehicle is not in the D range in step G98, A high-speed travel cancel flag is set, and in step G99, the minimum set travel speed for constant-speed travel is set to 4.
When it is determined that the speed is less than Q Km/h, a constant speed running cancel flag is set, and when it is determined in step G7 that the time-up of the shift timer is determined in step G8, the 20-speed A/D is set in step G9. You can take down the flag. Then, in step G39, the state of the ECT-A/D flag is determined, and when the ECT-A/D flag is down, a shift timer for automatic shift control is selected, and further, in step G93, the ECT-A/D flag is When it is confirmed that the D flag is lowered, automatic shift control can be entered from automatic shift constant speed running control.

Further, regarding the routine from step G30 to step G35, EC is performed using a general flow chart showing partial details of the general flow chart of FIGS. 7 and 8.
Lockup control during T-A/D control will be explained in detail.

If the ECT-A/D flag is set in step 1 (G30), it is determined whether automatic gear shift constant speed driving control is in progress, and if the ECT-A/D flag is set, in step 2 Calculate the vehicle speed deviation by subtracting the set vehicle speed. In step 3, it is determined whether the vehicle speed deviation is negative, and if it is negative, in step 4, the vehicle speed deviation is multiplied by "-1" to obtain the absolute value of the vehicle speed deviation. In step 5, it is determined whether the absolute value of the vehicle speed deviation is greater than a predetermined threshold of 2 Km/h. When the absolute value of the vehicle speed deviation is greater than a predetermined threshold value, the lockup permission flag is lowered in step 6 to release the lockup. In step 7, the lock-up prohibition timer Tim[ is set to 5 seconds. Lock-up prohibition timer T is set in step 8.
Start 1m1J, release the lock-up clutch in step 9, and move to step G of the main program.
Step 36 begins.

This state continues until the absolute value of the vehicle speed deviation becomes less than or equal to the predetermined threshold of 2 Km/h in step 5, and the absolute value of the vehicle speed deviation is greater than the predetermined threshold of Q, 5 Km/h in step 1Q. Ru.

Further, in step 5, the absolute value of the vehicle speed deviation is set to 2 of the predetermined threshold.
Km/h or less, and furthermore, when the absolute value of the vehicle speed deviation becomes smaller than a predetermined threshold Q, 5 Km/h in step 10, a lock-up permission flag is set to perform lock-up in step 11.

Next, lockup determination processing is performed in step G47 of the general flowchart. The outline will be explained below.

First, in step 21, the lock-up prohibition timer Tim
[Determine if is zero. In step 22, it is determined whether the lockup permission flag is set to release the lockup. When the lock-up prohibition timer TimII is zero and the lock-up permission flag is set, step 23
Performs lock-up control.

This will be explained using the timing chart shown in FIG. 13 which shows an example of the control state of the lock-up clutch.

When the road gradient of the vehicle approaches 3% to 3.5%, the vehicle speed decreases and the throttle opening is increased to compensate for the decreased vehicle speed. At this time, if the insufficient driving force can be compensated for by the torque converter's ability, constant speed running can be maintained without changing gears by performing lock-up control. At this time, if lock-up control is not performed, the gear shift will be performed even if the insufficient driving force can be compensated for by the torque converter's ability.

As described above, the speed control device of this embodiment is capable of controlling the automatic transmission constant speed driving control using the electronic control means when using an automatic transmission with a built-in torque converter with a lock-up clutch for automatic speed changing constant speed driving control. It is determined whether the vehicle speed deviation is greater than or equal to a predetermined threshold value during automatic shift constant speed running control, and when the vehicle speed deviation is greater than or equal to the predetermined threshold value, lockup is released and torque is obtained by the function of the torque converter. In this way, during constant speed driving control, regardless of the shift line of the automatic transmission, if a predetermined vehicle speed deviation becomes large, the lockup is released and the necessary driving force is obtained by the torque converter function, and the gear is shifted. This is to maintain constant speed driving control without any problems. When it is determined that the vehicle speed deviation is small enough to maintain the lock-up state, lock-up is permitted and the lock-up clutch is locked up to eliminate slip in the torque converter itself, eliminate losses caused by the torque converter, and improve fuel efficiency. It's something that will make you. In particular, the lock-up inhibition timer T i
If the torque converter built into the automatic transmission cannot compensate for the insufficient driving force even after a predetermined period of time has elapsed due to m■, the torque converter is locked up, so in this case, gear shifting is performed. It turns out.

Therefore, the speed control device of this embodiment is an automatic transmission control system that controls an automatic transmission with a built-in torque converter with a lock-up clutch according to a memory map that stores a shift line for selecting a gear position according to the rotational speed output and throttle opening. A speed control device is constituted by means, a constant speed running control means for controlling to maintain a predetermined set vehicle speed by controlling the throttle opening, and an electronic control means for selectively controlling the automatic shift control means and the constant speed running control means. Further, when the automatic shift control means and the constant speed traveling control means are in a controlled state by the electronic control means, the lock-up clutch is released when the vehicle speed deviation becomes large, and the lock-up clutch is released when the vehicle speed deviation becomes small. Since it is in the permission state, it is possible to release the lock-up of the torque converter and reduce the number of downshifts when changing gears during constant speed driving control, and it is possible to reduce the number of downshifts when changing gears during constant speed driving control. The control of the throttle opening degree in the constant-speed running control becomes a factor in shifting the automatic shift control device, and it is possible to prevent the number of gear changes during the automatic shift constant-speed running control from increasing.

Under normal driving conditions, when it is determined that the vehicle speed deviation is small enough to maintain the lock-up state, the torque converter is locked up and the lock-up clutch is locked up to eliminate slip in the torque converter itself and reduce fuel consumption. can be improved.

Note that the automatic transmission control means for controlling the automatic transmission with a built-in torque converter with a lock-up clutch according to the above-mentioned embodiment according to a memory map that stores a shift line for selecting a gear position according to the rotational speed output and the throttle opening degree is a known automatic transmission control means. The automatic transmission has a configuration equivalent to an independent automatic transmission control device including an automatic transmission and a control circuit for controlling it. In addition, the constant speed running control means that controls the vehicle speed to maintain a predetermined set vehicle speed by controlling the throttle opening is a means for controlling the vehicle to maintain a predetermined vehicle speed by controlling the opening and closing of the throttle opening.
It has a configuration that corresponds to a known constant speed cruise control device that can independently perform constant speed cruise control.

Furthermore, in the embodiment described above, constant speed running control is performed by control mainly based on the automatic speed change control means, but when implementing the present invention, automatic Shift control may also be performed.

[Effects of the Invention] As described above, the speed control device of the present invention controls an automatic transmission with a built-in torque converter with a lock-up clutch to change gears according to vehicle speed or rotational speed output, engine load, or throttle opening. an automatic shift control means; a constant speed running control means for controlling the throttle opening to maintain a predetermined set vehicle speed; When the constant speed running control means is in the controlled state, the vehicle is equipped with electronic control means for releasing the lock-up clutch when the vehicle speed deviation becomes large and enabling the lock-up clutch when the vehicle speed deviation becomes small. Therefore, if the torque converter function compensates for insufficient torque during constant speed driving, the driving force can be compensated for without downshifting, and automatic shift control means and constant speed driving control The number of gear changes during operation of the means can be reduced. Therefore, the number of times the vehicle is shifted during driving can be reduced, and the discomfort experienced by the occupant due to the shock caused during gear shifting can be reduced.

[Brief explanation of drawings]

FIG. 1 is a control circuit diagram configuring the electronic control means of a speed control device according to an embodiment of the present invention, FIGS. 2 to 6 are general flowcharts for controlling the speed control device according to an embodiment of the present invention, and FIG. 8 is a general flowchart showing partial details of the general flowchart, FIG. 9 is a shift map for automatic shift according to an embodiment of the present invention, FIG. 10 is a lockup map for automatic shift according to an embodiment of the present invention, and FIG. The figure also shows a shift map for automatic transmission constant speed driving, FIG. 12 shows a lock-up map for automatic transmission constant speed driving, FIG. 13 shows a timing chart illustrating the control state of the lock-up clutch, and FIG. This is the speed change map of the speed change control device. In the figure, CPU: Microcomputer, SPS: Shift position switch, SS: Throttle opening sensor, BS Ni-brake switch, PK: Parking brake switch, SP Nijo set switch R8: Resume switch, ADS: Constant speed main switch, SLl, SL2: Shift solenoid, SL3: Lock-up solenoid, RV: Release valve, CV: Control valve, VP: Vacuum pump. In addition, in the figures, the same reference numerals and the same symbols indicate the same or equivalent parts. Patent applicant: Aisin Seiki Co., Ltd. Figure 9 Figure 10 Speed sensor υ output Rotational speed [4'? PM] Fig. 11 Speed sensor output Rotation Wl [RPM] Fig. 12 Speed sensor output Rotation speed [RPM] Fig. 13 Fig. 14

Claims (2)

[Claims] (1) Automatic transmission control means that controls an automatic transmission with a built-in torque converter with a lock-up clutch to change gears according to vehicle speed or rotational speed output, engine load, or throttle opening, and a predetermined setting by controlling the throttle opening. A constant speed running control means that controls to maintain the vehicle speed, and selectively controlling the automatic shift control means and the constant speed running control means, and when the automatic shift control means and the constant speed running control means are in the controlled state, the vehicle speed deviation is large. 1. A speed control device comprising: electronic control means for releasing a lock-up clutch when the vehicle speed deviation becomes small, and enabling the lock-up clutch when the vehicle speed deviation becomes small. (2) The speed control device according to claim 1, wherein the lock-up clutch is released after a predetermined time limit when the vehicle speed deviation becomes large.