JPH0351216Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a constant speed traveling device for driving a vehicle at a constant speed set by a driver.

(Prior Art) Constant-speed traveling devices for vehicles have recently been adopted in many vehicles from the viewpoint of reducing driver fatigue and saving fuel consumption when driving on highways.

By the way, this constant speed traveling device generally operates by turning the constant speed traveling switch when the vehicle speed reaches a predetermined speed.
When turned on, the vehicle will drive at a constant speed using the current speed as the set vehicle speed. The relationship between vehicle speed and throttle opening for constant speed driving is
In general, control lines are determined depending on whether the road is flat, uphill, or downhill, and the throttle opening for vehicle speed control is adjusted along the above control line in response to changes in running resistance due to changes in the road. It is becoming more and more controlled. The above control line is stored in the microcomputer of the constant speed running control unit.

Therefore, when driving uphill, the actual vehicle speed is first detected and this vehicle speed signal is input to the controller, and the vehicle speed signal value when the constant speed driving switch is ON is stored and set as the set vehicle speed. There is a known technique in which the tilt angle of the vehicle is separately detected by a tilt angle detection means, the control value is determined based on this detection signal, and the set vehicle speed is corrected and changed (for example, Utility Model Application No. 57-198612). (see official bulletin).

However, in the configuration of this prior art, since the inclination angle detection means is constituted by a potentiometer having a weight that maintains a vertical state suspended from its rotation axis, it is difficult to use an expensive potentiometer, for example. Requires a yometer; Errors are likely to occur in the detection signal due to vibration of the weight due to changes in vehicle speed; The detection signal is an analog signal, making it unsuitable for digital processing; Trackability of tilt angle detection with changes in vehicle speed. There are drawbacks such as poor performance, and at the same time, there is a drawback that it becomes difficult to drive at the set vehicle speed.

(Purpose of the invention) The present invention was made to improve the above-mentioned drawbacks, and is capable of maintaining constant speed running on uphill slopes with accuracy and good followability, and is also inexpensive in terms of constant speed running for vehicles. The purpose is to provide a device.

(Means for Achieving the Object) In order to achieve the above object, the present invention provides a speed control means for controlling the throttle opening so that the vehicle travels at a constant speed set by the vehicle speed setting operation, and a transmission. In a constant speed traveling device for a vehicle equipped with an automatic transmission that automatically performs a gear change operation, a deceleration change detection means for detecting a deceleration change in the actual vehicle speed with respect to the set vehicle speed, and an input from the deceleration change detection means a shift-down control means for supplying a shift-up prohibition command signal and a shift-down command signal to the automatic transmission when a change in deceleration exceeds a predetermined value; and a shift-down control means for setting a predetermined vehicle speed range for the set vehicle speed. , stores the throttle opening degrees in each case when the vehicle speed exceeds the set vehicle speed range after the transmission downshifts and when the vehicle speed is within the set vehicle speed range after the transmission downshifts. Throttle opening storage means; and shift-up inhibition canceling means for canceling the shift-up inhibition state caused by the shift-up inhibition command signal when the actual opening in the driving state becomes smaller than the opening stored in the throttle opening storage means. It is characterized by the fact that

(Operation) According to the above means, when traveling uphill,
When the amount of deceleration change in the actual vehicle speed with respect to the set vehicle speed becomes greater than a predetermined value, it is determined that the slope is uphill, the automatic transmission is downshifted and at the same time upshifting is prohibited, allowing constant speed driving at the predetermined set vehicle speed.
In addition, special analog sensors such as potentiometers that detect the angle of inclination of the road surface are no longer required, making it suitable for digital processing. Since only changes are required, manufacturing costs can also be reduced. Furthermore, in the above configuration, a predetermined vehicle speed range is set for the set vehicle speed during constant speed driving, and the throttle opening is adjusted in each case when the actual vehicle speed exceeds the vehicle speed range after the downshift and when it does not exceed the vehicle speed range. is stored in memory, and upshifting is only possible when the actual throttle opening during driving becomes smaller than the memorized opening. Therefore, it is possible to perform control with good responsiveness without causing hunting in accordance with the current traveling vehicle speed.

(Embodiment) Drawings 1 to 3 show an embodiment of the present invention, in which Fig. 1 is a control circuit diagram of a constant speed traveling device for a vehicle according to the embodiment, and Fig. 2 is a control circuit diagram of a constant speed traveling device for a vehicle according to the embodiment. A flowchart showing all the control operations of the automatic transmission control including the constant speed running function of the device according to the example, and FIG. 3 is a flowchart showing the control operations of the automatic transmission control during constant speed driving of the device according to the above embodiment. It is.

First, the control circuit shown in FIG. 1 will be explained, and then the control operation shown in FIGS. 2 and 3 will be explained.

In FIG. 1, reference numeral 1 indicates a control unit for constant speed running control, and this control unit 1 mainly includes a microcomputer (CPU), an interface (I/0) section, and a memory section (RAM and ROM). It is composed of: The interface section of the control unit 1 contains a memory value signal stored in the storage means 4 for the throttle opening signal when the vehicle speed is set by the vehicle speed setting means 2, as well as a direct throttle opening detection means 3.
Throttle opening signal at that time detected by
The deceleration detection signals detected by the deceleration detection means 6 (corresponding to the deceleration change detection means in the claims of the utility model registration) are respectively inputted.

The vehicle speed setting means 2 is constituted by, for example, a set switch for constant speed driving, and causes the storage means 4 to read the throttle opening corresponding to the instantaneous vehicle speed when the driver turns on the set switch. This storage signal is then supplied to the control unit 1 as described above.

The deceleration detection means 6 compares the vehicle speed detection signal from the vehicle speed detection means 5 with the set vehicle speed signal, detects that the detection signal is a negative change with respect to the set vehicle speed, and converts the detected value as described above. is supplied to the control unit 1. Based on the above inputs, the control unit 1 operates as shown in FIG.
The control operation shown in the flowchart of FIG. 3 is performed, and the shift-up prohibition command signal 7 and the shift-down command signal 8 or the shift-up inhibition cancellation signal 9 are outputted, and the automatic transmission is controlled according to the flowchart of FIG. , control unit 1
functions as a downshift control means and a shift up prohibition release means within the scope of the utility model registration claim).

Next, the basic control operation of the automatic transmission in this embodiment will be explained using the flowchart of FIG.

First of all, control unit 1
The count value T of the shift timer is initialized in accordance with S ₁ to _{S 3} and set to a predetermined initial value at the time of shift change of the automatic transmission.
After decrementing by 1, input the shift range set by the shift lever. If the range of the automatic transmission is determined in step _S4 and range 1 is set, steps _S5 to _S9 are executed from step _S4 . That is, first, the lockup is released (step _S5 ), and it is calculated (step _S6 ) whether or not the engine rotation will overrun when downshifting to 1st gear, and then confirmed (step _S7 ).
Then, if an overrun occurs, the gear is shifted to second gear (step S ₈ ), and if there is no overrun, the gear is shifted to first gear (step S ₉ ). If the gear is set to range 2, steps _S4 to _S10 to _S12 are executed to release the lock-up and then shift to second gear.

On the other hand, other than range 1 and range 2, that is, D
(Drive) range, step _S13 moves to constant speed driving control operation (auto speed control, abbreviated as auto speed control in the following explanation and drawings).
Execute _S14 to _S16 . In the shift-up control in step _S14 , after confirming that the automatic transmission gear mechanism is in a state in which shift-up is possible for speeds other than 4th, the shift-up is performed based on the data of the shift-up map and the current transmission turbine rotation speed. In addition, in the shift down control in step _S15 , after confirming that the automatic transmission gear mechanism is in a state where downshifts other than 1st gear are possible, downshifting is performed based on the data of the shift down map and the current transmission turbine rotation speed. Take control. Furthermore, in the lock-up control in step _S16 , the lock-up control is performed based on the lock-up map data and the current transmission turbine rotation speed, provided that a predetermined time has elapsed since the shift timer count value. conduct.

When one cycle of each of the above-mentioned controls is completed, step _S17 is executed for a predetermined period of time (for example,
After a delay time of 50 msec), control operation for the next cycle is started.

Next, the control operation during the constant speed running control shown in FIG. 3 will be explained in more detail.

First, when the control operation is started, step _S1
Input (read) the operating state (ON or OFF) of the set switch for constant speed driving control (auto speed control) to the control unit 1 shown in Fig. 1 above. Next, in step _S2 , turn on the switch,
OFF is determined from the above input, and if it is OFF (NO), the control operation is ended (END), while ON
If (YES), the process moves to step _S3 , where the vehicle speed change signal from the deceleration detection means 6 shown in FIG. 1 is input. This vehicle speed change is a negative change (deceleration) in the actual vehicle speed relative to the set vehicle speed within a certain period of time.
This means that the value corresponds to the running resistance (angle of inclination) when the running road is uphill. Next, in step _S4 , it is determined whether this change in vehicle speed is larger or smaller than a predetermined value X. If it is smaller (NO), it is recognized that the road is substantially flat and the control operation is ended. On the other hand, if the vehicle speed change is greater than X (YES), it is recognized that the vehicle is going uphill;
Furthermore, it is compared with a predetermined value Y that is larger than X (step S ₅ ). As a result of this comparison, if the vehicle speed change is smaller than Y (NO), the process moves to step _S7 , where a shift-up prohibition command signal and a shift-down command signal are generated, and the automatic transmission is shifted down by one gear. .

On the other hand, if the vehicle speed change is greater than Y (YES), the automatic transmission is similarly downshifted by two gears (step _S6 ).

Next, when the above-mentioned control operations are completed, control operations proceed to steps _S8 to _S19 for maintaining the set vehicle speed. First, in step _S8 , a vehicle speed value A ₁ (=A+α), which is the set vehicle speed A set by the vehicle speed setting means 2 shown in FIG. 1 and a predetermined hysteresis value (insensitive value) α, is input. Then, in the next step _S9 , the actual vehicle speed B is compared with the above _A1 . As a result, if the actual vehicle speed B is greater than _A1 (YES), proceed directly to the step described below.
The process moves on to the memorization operation of the throttle opening degree θ in _S17 . On the other hand,
If the actual vehicle speed B is smaller than _A1 (NO), further input a vehicle speed value _A2 (=A-α) obtained by subtracting the predetermined hysteresis value α from the set vehicle speed A (step _S10 ); Next, in step _S11 , the actual vehicle speed B is compared again. As a result, if the actual vehicle speed B is smaller than the above _A2 , the control operation is ended (END). On the other hand, if the actual vehicle speed B is greater than _A2 (YES),
The above-mentioned speed change timer (FLAG: 1) is determined (step _S12 ). As a result, if it is not FLAG1 (NO), a new timer set (step
S ₁₃ ) and then FLAG set (step
_S14 ) to end the control operation.

On the other hand, if FLAG1 is on (YES), enter the timer count value in step _S15 ,
In step _S16 , it is determined whether the count value is 0 or not.

As a result, when the count value of the timer is not 0 (NO), the control operation is ended (END), and the other timer is 0.
In the case (YES), in the next step _S17 , the throttle opening θ when the vehicle speed returns to the set speed detected by the throttle opening detecting means 3 shown in FIG. 1 is stored in the storage means 4. Then step
In _S18 , the current throttle opening θ ₁ during running, which has elapsed for a predetermined period of time since the time of storage, is compared with the throttle opening θ stored in the storage means 4. As a result, if θ ₁ is smaller than θ (YES), the shift-up prohibition state is canceled and the normal shift operation in step _S19 is executed, and then the control operation is ended (END).
However, if θ ₁ is larger than θ (NO), the control operation is ended (END).

In the above control operation, if a timer is not used, the above-mentioned shift-up inhibited state is canceled immediately when the vehicle speed returns to the set speed based on the throttle opening.

(Effects of the invention) As explained above, the present invention automatically controls the speed control means that controls the throttle opening so that the vehicle travels at a constant speed set by the vehicle speed setting operation, and the speed change operation of the transmission. In a constant speed traveling device for a vehicle equipped with an automatic transmission that performs automatic transmission, there is provided a deceleration change detection means for detecting a deceleration change in the actual vehicle speed with respect to the set vehicle speed, and a deceleration change detection means that detects a change in deceleration based on an input from the deceleration change detection means. a shift-down control means for supplying a shift-up prohibition command signal and a shift-down command signal to the automatic transmission when the speed exceeds the set vehicle speed; Throttle opening storage means for storing the throttle opening in each case when the vehicle speed exceeds the set vehicle speed range and when the vehicle speed is within the set vehicle speed range after the transmission is downshifted; and a shift-up inhibition canceling means for canceling the shift-up inhibited state caused by the shift-up inhibition command signal when the actual throttle opening in the running state becomes smaller than the throttle opening stored in the throttle opening storage means. It is something to do.

Therefore, for example, when the road surface is an uphill slope, the slope state is accurately detected as a negative change in the actual vehicle speed with respect to the set vehicle speed, and the set vehicle speed can be maintained. Furthermore, in the above configuration, in this case, a predetermined vehicle speed range is set for the set vehicle speed during constant speed driving, and in each case when the actual vehicle speed exceeds the vehicle speed range after the downshift and when it does not exceed the vehicle speed range. The throttle opening degree is memorized, and upshifting is only possible when the actual throttle opening degree during driving becomes smaller than the memorized opening degree. Therefore, it is possible to perform control with good responsiveness without causing hunting in accordance with the current traveling vehicle speed. Moreover, in that case, there is no need for a special sensor for detecting road surface inclination such as a conventional potentiometer, and a normal vehicle speed detection means can be used.
Since it can be used as is, the cost is low. Furthermore, since the detection signal of the vehicle speed detection means is normally output in the form of a pulse signal, it is accurate and suitable for digital processing. Therefore, the above-mentioned drawbacks of the conventional method do not occur. Further, since the configuration of the entire control device can be easily realized by only changing a part of the interface part of the control unit and adding a control program, there is no increase in cost in this respect as well.

[Brief explanation of the drawing]

FIG. 1 is a control circuit diagram of a constant speed traveling device for a vehicle according to an embodiment of the present invention, FIG. 2 is a flowchart for schematically explaining the overall automatic transmission control operation in the device, and FIG. The figure is a flowchart of the constant speed running operation of the above device when running uphill. DESCRIPTION OF SYMBOLS 1...Control unit, 2...Vehicle speed setting means, 3...Throttle opening detection means, 4...Storage means, 5...Vehicle speed detection means, 6...Deceleration detection means.

Claims (1)

[Scope of utility model registration request] In a constant speed traveling device for a vehicle, comprising a speed control means that controls a throttle opening so that the vehicle travels at a constant speed at a set speed set by a vehicle speed setting operation, and an automatic transmission that automatically performs a gear shifting operation of the transmission. , a deceleration change detection means for detecting a deceleration change in the actual vehicle speed with respect to the set vehicle speed, and a shift-up prohibition command signal to the automatic transmission when the change in deceleration based on the input from the deceleration change detection means exceeds a predetermined value. and a shift-down control means for supplying a shift-down command signal; and a shift-down control means that sets a predetermined vehicle speed range for the set vehicle speed, and when the vehicle speed exceeds the set vehicle speed range after the transmission is downshifted, and when the same gear shift is performed. a throttle opening storage means for storing the throttle opening in each case when the vehicle speed is within the set vehicle speed range after downshifting; A constant speed traveling device for a vehicle, comprising a shift-up prohibition canceling means for canceling the shift-up prohibition state caused by the shift-up prohibition command signal when the actual opening becomes small.