JPH01160736A - Constant speed running control device - Google Patents

Abstract

PURPOSE:To make it possible to exactly compute a throttle opening on the output of a stroke sensor by correcting the play of an actuator stroke by monitoring an idle switch. CONSTITUTION:A stroke Li is detected at the working point of an idle switch, and a throttle opening Q is computed by the equation, Q=(L-Li)XK1+Qi, in which K1, L and Qi denote throttle opening/stroke (proportion constant), the stroke of an actuator and the throttle opening, respectively.

Description

[Detailed Description of the Invention] [Summary] This is a constant running travel control device in which there is play in the stroke of the actuator that adjusts the throttle opening. Calculated using a formula using degrees.

[Industrial application field]

The present invention relates to a constant traveling control device that calculates a throttle opening degree from an actuator stroke.

[Conventional technology]

A constant speed cruise control (autodrive) device is a device that uses an actuator to control the engine's throttle valve in order to maintain a constant vehicle speed.In order to accurately control the throttle opening, a stroke sensor is built into the actuator. There is a method in which the signal is returned to the control device.

FIG. 2 shows an example of this, in which l is a computer for constant speed running control, 2 is an actuator, 3 is a built-in stroke sensor, 4 is a throttle, and 5 is its return spring.

When the set switch is pressed, the computer 1 stores the vehicle speed at that time as the target vehicle speed, and thereafter performs erratic driving control until a cancel signal from the brake or the like is input. That is, by changing the control signal given to the actuator 2, the opening degree of the throttle 4 is changed around eight times. At this time, the throttle opening degree is calculated based on the signal from the stroke sensor 3 to improve control accuracy.

[Problem that the invention seeks to solve]

By the way, the actuator 2 has some play so that when the accelerator pedal (not shown) is not depressed, there is no idle amplifier and the throttle valve is reliably fully closed. Therefore, the throttle opening remains fully closed until a certain stroke, so if this play is large, the throttle opening calculated based on the stroke sensor signal will differ greatly from the actual value, making accurate control impossible.

For example, in the characteristic diagram of actuator stroke L and throttle opening θ as shown in Fig. 3, if the design center indicated by the solid line is set with a play of 51 mm, the actual example indicated by the broken line If there is a play of 101, the following error will occur. In other words, a straight line with the same slope as the design center and an allowance of 01 m passes through θ=80° at L=40 fins. This L
=40m is a full stroke Lli'! θ-80° is the corresponding maximum throttle opening θM. On the other hand, the design center that allows play of 5 dragons has an effective stroke of 35 tm (=40 sm - 5 mm), and the throttle opening changes only from 0° to 70° during that full stroke. Furthermore, in an example where the play is 10 dragons, there is a difference of 5 M■ in play and 10% in throttle opening compared to the design center.

An error in the throttle opening amount due to play in the actuator stroke appears as a deviation in the traveling vehicle speed. FIG. 4 is an explanatory diagram of this. The throttle opening corresponding to the cent vehicle speed is set as the initial opening θS, and the target opening is determined according to the control line. If the vehicle speed falls below the cent vehicle speed, the target opening degree is increased to increase the speed, and conversely, if the vehicle speed increases above the cent vehicle speed, the target opening degree is lowered and the vehicle is decelerated, thereby controlling the vehicle to travel at the cent vehicle speed.

According to this logic, a set deviation occurs if the initial opening degree θS is not set appropriately. For example, if an opening degree of θ1 is actually required, the vehicle speed is decelerated along the control line from point A, and the vehicle speed is controlled to be lower than the set vehicle speed at point B. For this reason, methods are known to eliminate the set deviation by integrally correcting the initial opening degree θS, but if the correction speed is too fast, hunting may be induced, so it is difficult to quickly converge the deviation.

As shown in FIG. 3, a phenomenon similar to that shown in FIG. 4 also occurs when the deviation between the stroke L and the throttle opening θ is large. For example, at θ5-20%, the stroke L deviation is 5 degrees (1 degree in opening).
0%), the result is actually the same as setting θ5-10%, resulting in a significant decrease in vehicle speed.

The present invention attempts to correct the play in the actuator stroke described above by monitoring the idle switch.

[Means for solving problems]

The present invention provides a fixed connection system for a vehicle that is equipped with an actuator that adjusts a throttle opening (θ), a sensor that detects the stroke (L) of the actuator, and an idle switch that operates at a predetermined throttle opening (θi). The driving control device is characterized in that the stroke (Li) at the operating point of the idle switch is detected, and the throttle opening degree (θ) is calculated using the following formula.

[Effect]

The operating point of the idle switch is the specific throttle opening (θi
), the output (Li) of the stroke sensor when the switch operates is memorized, and Li in the throttle opening (θ) calculation formula 0 is calculated from the fixed value based on the design for each system. If the value is corrected to the value actually obtained, the throttle opening degree (θ) can be calculated without being affected by the play of the actuator stroke (L).

(Example) Fig. 1 is a flowchart showing an embodiment of the present invention.Step S1 is the initial setting of Li, and the design-centered play 5 dragon in Fig. 3 is temporarily set.Next, in step S2, the automatic The vehicle speed Vn required for drive control is measured.Then, if the cancel SW is ON, 1. Auto drive control is not performed, so the control flag is set (steps S3 and S4), but if the set SW is ON, A control flag is set (steps S5 and S6).Then, in step S7, the vehicle speed Vn at that time is stored as cent vehicle speed Vm, and auto drive control is started.

When the setting of the control flag is confirmed in step S8, the actuator stroke Ln is detected in step S9. Then, in step SIO, the idle switch turns from ON to OFF.
When it changes to FF (operating point), the stroke L at that time
n is reset to Li (step SIO, 5ll).

In the example of FIG. 3 (dashed line), L i = l l mm. Step S12 is the calculation of the current throttle opening degree θn, and K1 is a proportionality constant indicating the slope shown in FIG. Step S13 converts the difference between the set vehicle speed Vm and the actual vehicle speed VnO into the target opening degree θ.
In the calculation reflected in A, G is the control gain showing the slope in FIG.

If the obtained θ is θn and θA>θn, the actuator is operated at an increased speed (step S14゜515);
Conversely, when θ8<θn, deceleration is performed (steps 316, 517). Furthermore, when θA=θn, the operation of the actuator is stopped (step 818).
.

〔Effect of the invention〕

As described above, according to the present invention, there is an advantage that the throttle opening degree can be accurately calculated from the output of the stroke sensor in a constant running traveling control device using an actuator with play in the stroke.

[Brief explanation of the drawing]

Fig. 1 is a flowchart showing an embodiment of the present invention, Fig. 2 is a configuration diagram of a constant traveling control device, Fig. 3 is a characteristic diagram showing the relationship between actuator stroke and throttle opening, and Fig. 4 is a vehicle speed diagram. It is a control characteristic diagram which shows the relationship between and a target opening degree. Applicant Fujitsu Ten Ltd. Representative Patent Attorney Minoru Aoyagi - 5 謬Hahej・嬶】[Sendqki℃P.

Claims (1)

[Claims] A vehicle equipped with an actuator that adjusts the throttle opening (θ), a sensor that detects the stroke (L) of the actuator, and an idle switch that operates at a predetermined throttle opening (θi). In the constant traveling control device, the stroke (Li) at the operating point of the idle switch
A constant speed cruise control device that detects and calculates the throttle opening (θ) using the following formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼.