JPH02175338A - Constant speed running control device for car - Google Patents

Abstract

PURPOSE:To eliminate any protection circuit and simplify the device configuration by incorporating such a constitution that the gain of control output to an actuator is made relatively small in case the integrated value of this control output for every constant speed run exceeds the equivalent to at least one of the stroke limits of the actuator. CONSTITUTION:A car speed calculating means 3 calculates actual car speed on the basis of the period of output signals from a car speed sensor 2, and the result from calculation is fed to a constant speed running control means 8. In case a set signal is given by a constant speed running command means 4, the actual car speed at the time is set to the target car speed value, and thereafter the degree of opening of a throttle valve 7 is controlled by an actuator 5 according to the control amount based on the deviation of actual car speed from its target value. At this time, the control output from the constant speed running control means 8 is fed to an actuator motion amount sensing means 9, and the integral value of the input signal is compared with the threshold value. If the integral value exceeds the equivalent to at least one of the stroke limits of the actuator 5, the gain of the control output shall be varied to a relatively small value.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a constant speed cruise control device for a vehicle that automatically keeps the traveling speed of a vehicle constant.

[Prior Art] A conventional constant speed cruise control device for a vehicle detects the traveling speed of the vehicle using a vehicle speed detection means, and is installed in the intake pipe of the engine based on the constantly detected traveling speed and a target speed. The control amount of the actuator that controls the opening and closing of the throttle valve is calculated by the constant speed running control means, and the actuator is driven based on the calculation result to adjust the opening degree of the throttle valve so that the running speed is equal to the target speed. There were 41 regulations. As this actuator, an electric motor type actuator that uses a DC motor as its drive source is known, but in its fully open position, the stroke is mechanically limited and the stroke is mechanically locked. For this reason, an excessive current flows through the motor armature due to the opening direction command and the closing direction command from the constant speed traveling control means that outputs a control signal to the actuator, and the DC motor and its drive circuit generate heat. In the worst case, it will burn out.

For this reason, in conventional devices, the throttle valve is fully opened,
A limit switch is installed to detect the fully closed position, fully open,
When the actuator stroke reaches the fully open position,
The command signal from the constant speed traveling control means was mechanically cut off by the switch operation of the limit switch. This will be explained in detail with reference to FIG.

In Fig. 5, 101 is a DC motor, 102゜103
A beam mint switch, 104 and 105 are diodes that regulate the current direction, and 106. ．． 107 is a terminal, 10B is an electromagnetic clutch for engaging and disengaging the rotating shaft of the DC motor 101 and the valve shaft of the throttle valve 109, and 110 and 111 are the terminals thereof. When driving the throttle valve 109, the terminal 1
．． 10. An electromagnetic clutch to which a signal was applied between 111 and 1.
08 operates to engage the rotating shaft of the DC motor 101 and the valve shaft of the throttle valve +09. In this state, terminal 106
．． When a drive signal is applied between 107 and t current flows through the DC motor 101, the DC motor 101 rotates and drives the throttle valve 309 to rotate.

When the throttle valve 109 is in the fully open (or fully closed) position, the corresponding one of the limit switches 102 and 103 is operated from the illustrated position by the pressing action of an arm (not shown) attached to the valve shaft, and the diode 104. 105
Close (or open) the DC motor 101 only to the corresponding one of the
Allows flow to rotate in one direction only, and prevents flow in the opposite direction.

[Problem to be solved by the invention]

Since the conventional constant speed running control device for a vehicle is configured as described above, the actuator circuit may open or short circuit due to poor contact of the electric contacts of the limit switch 102103, and when the limit switch 102103 is opened, the DC motor 101 cannot be energized. Because there is no constant speed running control, there is a problem that in the event of a short circuit, an excessive current flows through the armature of the DC motor 101, causing it to burn out.

In addition, since electric elements such as diodes 1.04 and 105 are required, it is necessary to incorporate an electric circuit inside the actuator, making the distribution and image configuration complicated and expensive.
- Actuators are often installed in the engine room for boat fishing, and in order to protect the circuit from the external environment, the design must take into consideration water intrusion, dust, etc., which poses problems such as troublesome design. .

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a constant speed cruise control device for a vehicle that can omit an actuator protection circuit composed of a limit switch and the like.

[Means to solve the problem]

The constant-speed running i control device for a vehicle according to the present invention controls the actuator every time the vehicle runs at a constant speed. The gain of the control output is reduced when the integral value of the l output exceeds at least one of its stroke limits.

[For production]

The constant speed cruise control device for a vehicle according to the present invention detects the movement amount of the actuator by integrating the control output of the actuator, and when the stroke limit is exceeded, the gain of the lI#l output is reduced and the output is sent to the actuator. Reduce the amount of current.

(Example〕 Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an apparatus according to an embodiment of the present invention. In FIG. 1, I is composed of a vehicle speed sensor 2 that outputs a pulse signal with a frequency corresponding to the vehicle speed, and a vehicle speed calculation means 3 that calculates the vehicle speed based on the measured value of the period of this pulse signal, and calculates the actual vehicle speed. Vehicle speed detection means for detecting, 4
is a constant speed running command 7 means for generating signals for instructing various modes of constant speed running (for example, 7 speeds, cancel, etc.).

An actuator 5 opens and closes a throttle valve 7 installed in an intake pipe 6 of an engine (not shown), and is composed of, for example, a DC motor. Reference numeral 8 denotes a constant speed running control means for controlling constant speed running, which inputs each output signal of the vehicle speed detection means 1, constant speed running command means 4, and actuator movement amount detecting means 9 (described later), and controls constant speed running. A control signal is output to the actuator 5 to control the engine output so that the detected actual vehicle speed matches the target vehicle speed. Reference numeral 9 denotes actuator movement amount detection means whose detailed configuration is shown in FIG.
<' Input the II output and the output signal of the constant speed running command means 4, detect the movement amount of the actuator 5, compare it with the dark value corresponding to the fully open position of the stroke of the actuator 5, and determine the signal according to the comparison result. It is output to the speed running control means 8. 1
0 is a microcomputer consisting of a person, an output circuit, a CPU, a ROM, a RAM, etc. in which the flow shown in FIG. .

In FIG. 2, actuator movement amount detection means 9,
The actuator movement amount integrating means 11 that integrates the actuator movement amount, that is, the control output of the constant speed traveling control means 8, and the actuator movement! A comparison in which the magnitude of the integrated value of the actuator movement amount rj 4-value generation means 12 that generates a threshold value and the actuator movement amount integration means 11 is compared with the threshold value of the actuator movement amount threshold generation means 12, and a signal is output according to the comparison result. means 13. Reference numeral 14 denotes actuator gain changing means forming a part of the constant speed traveling control means 8, which variably sets the gain of the control tn output to the actuator 5 according to the comparison result from the comparison means 13.

Next, the operation will be briefly explained with reference to FIGS. 1 and 2.

When the vehicle is running, the vehicle speed sensor 2 generates a signal with a frequency corresponding to the vehicle speed. The actual vehicle speed is calculated by the vehicle speed calculation means 3 based on the period of the output signal of the vehicle speed sensor 2, and is inputted to the constant speed running control means 8. When the set signal S61 is generated from the constant speed running command means 4, the constant speed running control means 8 sets the vehicle speed V detected by the vehicle speed detection means 1 at that time to the target vehicle speed V. Thereafter, the constant speed running control means 8 calculates the control amount of the actuator 5 based on the vehicle speed V detected every moment and the target vehicle speed V, and outputs a control signal to the actuator 5. This causes the actuator 5 to operate and drive the throttle valve 7, increasing the engine output to 2B.

On the other hand, the control output of the constant speed traveling control means 8 is inputted to the actuator movement amount integrating means 11 of the actuator movement amount detection means 9 as an actuator opening direction command signal Sl or an actuator closing direction command signal S. The actuator movement amount integrating means 11 integrates the human power signal in the opening direction and the closing direction ((→, ←→ direction. The integral value S
, is compared with the dark value S1 output from the actuator movement amount dark value generating means 12. This dark value S corresponds to, for example, the fully open position of the stroke of the actuator 5, that is, the fully open position of the throttle valve 7. Its integral value S, and threshold value S
, then the gain change signal S of "1" from the comparing means 13
4 is output, otherwise r□.

A signal S4 is output. This gain change signal S.

The actuator gain changing means 14 inputs fl
'', the gain K is changed to 2, for example, and when the signal r□ is input, the gain K is left at 1. The constant speed running control means 8 uses the set gain K to control (determine the B output and supply it to the actuator 5,
Feedback is provided to the actuator movement amount detection means 9. In addition, when the actuator movement amount integrating means 11 inputs an initialization number 13 such as a cancel signal 5.8 from the constant speed running command means 4, the integral (i s x
, and the integral value S is locked to O so that it does not become the value H.

Next, the operation of the microcomputer]0 shown in FIG. 1 will be explained in detail with reference to FIG. In FIG. 3(a), step 20 is an initial value setting routine for constant speed driving, step 30 is a constant speed driving control routine,
Step 40 is a routine for determining the integrated value of the actuator movement amount, and after the processing of step 40, the process returns to step 30.

3) shows the details of the routine of step 40. In the same figure, in step 401, the fl neck of the control output is determined, and if the actuator opening direction command signal S+, then in step 402, the integral value S3 up to the previous time is determined. The current output amount is added to the current output amount to update the integral value, and if the actuator closing direction command signal S2, the previous integral value Sa is added in step 403.
The current output amount is subtracted from and the integral value is updated. Otherwise, or after processing either step 402 or 403, the process proceeds to step 404, where it is determined whether the integral value has fallen below the lower limit value 0, and whether or not an initial signal such as cancellation has been generated. , is below the lower limit value 0 or an initial signal is generated, in step 405 the integral (I S 3 is set to O; otherwise, the process proceeds to step 406. In step 406, the above integral value S,
It is determined whether or not is equal to or greater than the threshold value Sub, and if it is equal to or greater than the threshold value Sub, the gain change flag "IJ" is set in step 407.
Otherwise, the flag is reset in step 40B.

FIG. 3(C) shows details of the routine of step 30,
In the figure, in step 301, the detected actual vehicle speed V
, and the target vehicle speed V, based on the actuator system? 211
The pulse width T is calculated by calculating the amount. In step 302, it is determined whether the gain change flag is set or not, and if it is set, the gain K is changed to, for example, 2 in step 303, and the pulse width T calculated in step 301 is multiplied by the gain K to generate a pulse. Update width T. If it is a reset, do not change the gain K (=1.) and step 3
The pulse width T calculated in step 01 is left unchanged. This pulse width T is output as a pulse to the actuator 5 and the actuator movement amount detection means 9 as an actuator command signal.

FIG. 4 shows the timing of each signal in the above operation. In the figure, S represents vehicle speed command means 4.
cent signal S, r, reset signal S, !
, 5I-54, and S are already explained in the above operation, so their explanation will be omitted.

In the above embodiment, the gain K was changed to 2, but
Any other value smaller than 1 may be used, for example, as long as it provides an output amount with a pulse width that does not cause the DC motor or its drive circuit to generate heat and burn out at the fully open position of the actuator stroke.

Furthermore, although the above embodiments have been described for the opening direction side, the closing direction side can also be realized by the same means, and the same effects as in the above embodiments can be achieved.

Also, between step 40G and step 407, the integral value S
You may include processing to make , equal to the threshold (+IS),
In this case, the output signal of the comparing means I3 is fed back to the actuator movement M integrating means 11. Based on this feedback signal, the actuator movement amount integrating means II
is set to s, and if 2s is set to S, =S is set.

〔Effect of the invention〕

As described above, according to the present invention, when the integral value of the control output to the actuator exceeds at least one of its stroke limits during constant speed running, the gain of the control output is made relatively small. This eliminates the need for a protection circuit consisting of a limit switch, etc., which simplifies and lowers the cost of the device structure, and prevents the inability to control constant speed travel due to faulty electrical contacts and burnout of the actuator. This has the effect of improving safety and making it easier to design.

[Brief explanation of the drawing]

1 and 2 are block diagrams of a device according to an embodiment of the present invention, FIG. 3 is a flow diagram showing the operation of the microcomputer shown in FIG. 1, and FIG. 4 is a block diagram of the device according to the above embodiment. FIG. 5 is a configuration diagram of a conventional actuator, etc. In the figure, 1... vehicle speed detection means, 4... constant speed running command means, 5... actuator, 6... intake pipe, 7...
・Throttle valve, 8...Constant speed traveling auxiliary door means, 9...
- Actuator movement amount detection means, lO... microcomputer. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] A constant speed cruise control device for a vehicle that performs constant speed cruise control by providing a control output to an actuator that drives an engine throttle valve based on a target vehicle speed and a detected actual vehicle speed,
A constant speed vehicle characterized in that when the integral value of the control output to the actuator exceeds at least one stroke limit of the actuator, the gain of the control output is changed to a relatively small value. Travel control device.