JPS6194808A - Car height regulating method - Google Patents

Abstract

PURPOSE:To enable regulation of car height with high precision to prevent the occurrence of erroneous regulation, by a method wherein, when a car height value determined by averaging processing is outside a previously set proper car height value region, a compressor or an exhaust valve is actuated. CONSTITUTION:A car height sensor 1 is attached to a suspension 4, and a compressor 2 is driven by a motor 5. By means of an output signal which is computed by a controller 8 based on an output from the sensor 1, the motor 5 or an exhaust valve 3 is selectively operated and controlled. Provided the sampling time of a car height is set to 500msec and a car height averaging time is set to 5sec, car height is computed 10 times during a time between present and past. As described above, even if a car height is fluctuated resulting from the suspension (4)'s receipt of vibration during running, the car height values, exceeding a proper car height value, of car height values computed during a specified time are averaged for processing to discriminate a car height value, and this regulates a car height.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle height adjustment method for adjusting the vehicle height to a target vehicle height by controlling the supply and discharge of fluid to and from a suspension.

[Conventional technology]

In conventional vehicle height adjustment devices, when the vehicle height value detected by the vehicle height sensor is higher than the preset appropriate vehicle height, the controller stops driving the compressor, opens the exhaust valve, and bleeds air from the suspension. It lowers the vehicle height to the appropriate vehicle height, and if the vehicle height is lower than the appropriate vehicle height, it drives the compressor, closes the exhaust valve, introduces air pressure to the suspension, and raises the vehicle height to the appropriate vehicle height. It is configured as follows.

By the way, in such a conventional vehicle height adjustment device, for example, as shown in FIG. At the same time, if the vehicle height is initially low, the vehicle height is raised until it is higher than the appropriate position, and when the vehicle height becomes lower than the appropriate position again, the vehicle height control is finished. The vehicle height can be adjusted with high precision.

- [Problems to be Solved by the Invention] However, if such control is performed while the vehicle is running, the adjustment may end with the vehicle height completely deviating from the appropriate position.

Figure 6 (α) (h) shows such a situation.

In other words, if the vehicle height becomes lower than the proper positioning device even temporarily due to vibrations while the vehicle is running, the average value of the vehicle height will change as shown in Figure 6 (α
) Even though the vehicle height is at an extremely high position PH, the adjustment is finished at the vehicle height P, and even though the average vehicle height QH is at an extremely low position as shown in Figure 6 (15), the vehicle height Q is This will end the adjustment. Such poor vehicle height adjustment accuracy becomes more significant as the vibration amplitude increases.

The present invention has been made in view of these conventional problems, and it is an object of the present invention to provide a vehicle height adjustment method that enables appropriate vehicle height adjustment even while the vehicle is running.

[Means for solving problems]

In order to solve the above problems, the present invention includes the following steps: sampling vehicle height values at regular intervals; averaging the sampled vehicle height values at regular intervals;
This vehicle height adjustment method includes the steps of comparing the averaged vehicle height value with a preset appropriate vehicle height value, and selectively controlling the compressor or exhaust valve depending on the magnitude of this comparison value. be.

[For production]

In the present invention, the vehicle height values from the current time up to a certain period of time are sampled at regular intervals, and the average value of the sampled vehicle height values after the vehicle height exceeds the appropriate position is determined. When the high value is outside the set range determined as a reference, the compressor or exhaust valve is operated to adjust the vehicle height, and after the vehicle height adjustment, when the average value is within the set range, the vehicle height is adjusted. I'm trying to finish it. Therefore, even when the vehicle is running, the vehicle height can be controlled and maintained at the set vehicle height with high precision.

〔Example〕

Figure 1 shows a vehicle height adjustment device used to implement the method of the present invention. This is basically the same as the conventional one, but is different, especially in the vehicle height adjustment program in the controller. Briefly, 1 is a vehicle height sensor attached to the suspension 4, 2 is a compressor driven by a motor 5, 3 is an exhaust valve, 16 is a dryer, and 7 is a pressure sensor. A controller 8 selectively controls the operation of the motor 5 or the exhaust valve 3 based on an output signal calculated based on the output of the vehicle height sensor 1. When the vehicle height sensor 1 detects that the vehicle height is low, the controller 8 performs calculations described later to stop the motor 5.
Open exhaust valve 3 and lower the vehicle height to the appropriate level. Conversely, when the vehicle height sensor 1 detects that the vehicle height is low,
The controller 8 drives the motor 5, closes the exhaust valve 3, and raises the vehicle height to a proper vehicle height value. Next, the vehicle height adjustment method according to the present invention will be explained in detail according to the flowchart shown in FIG.

Ca) First, the counter of the controller 8 is the vehicle height sensor l.
For example, the vehicle height value is read 10 times at a time.
First, the number N of readings of the vehicle height value is reset to zero.

(6) Next, start reading the vehicle height value and increase the number of readings by N=N+1.

(C) While reading the vehicle height value, it is determined whether the Nth vehicle height value is higher or lower than the appropriate vehicle height value.

(d) If it is determined in step (c) that the value is low, reset the contents of the register for the Nth time.

(e) If it is determined in step (c) that the value is high, set the contents of the register for the Nth time.

(G) Here, it is determined whether the number of vehicle height readings N exceeds the number of averaged data M, and if it does not, it is determined that the averaging process is impossible and the vehicle height reading is continued again. let

0) However, if it is determined that the number of vehicle height readings N exceeds the number of averaging processing data M, averaging processing becomes possible, so the average of the vehicle height values read from the N-Mth time to the Nth time. Find the value S.

(A) Then, it is determined whether this average value S is a dog based on the vehicle height value (M/2+α) obtained by adding an error error of α to the appropriate vehicle height value M/2.

(and the average vehicle height value S is set as the vehicle height value (M
/2+α), the exhaust valve 3 is opened, the drive of the compressor 2 is stopped, and the air in the suspension 4 is removed to lower the vehicle height.

0) If it is determined in step (A) that S) is not M/2+α, then it is determined whether the average vehicle height value S is smaller than M/2−α.

(k) If it is determined that S<M/2-α, the exhaust valve 3 is closed, the compressor 2 is driven to supply air to the suspension 4, and the vehicle height is raised.

<1> Also, if it is determined that S(M/2-α is not the case at step (kl), then M/2-α<S<M/2+α, so the exhaust valve 3 closes and the compressor 2 stops, The averaged vehicle height value is held as being within the appropriate range.

Figure 3 and Figure 4 show an example of the above-mentioned averaging process method. According to this, the vehicle height sampling time is, for example, 5
00m5CC and the vehicle height averaging time is 5 Bec, the vehicle height values from the present to the past 10 times (M=10) are always calculated.

Further, α=2 is set in advance. According to this, M
The adjustment is completed when S<M/2+α, so 3
When <:S < 7, the adjustment ends.

In this way, even if the suspension 4 is subjected to vibrations and the vehicle height fluctuates while the vehicle is running, the vehicle height within a certain period of time is
By determining the vehicle height by averaging the vehicle height values when the vehicle height exceeds the appropriate vehicle height value, it is possible to adjust the vehicle height close to the appropriate vehicle height value.

〔Effect of the invention〕

According to the present invention, the vehicle height values near the appropriate vehicle height are averaged from the current time until a certain time ago, and the vehicle height value obtained by this averaging process is the preset appropriate vehicle height value. By activating the compressor or exhaust valve when the vehicle is outside the range, the vehicle height can be adjusted with high precision to around the appropriate vehicle height value while the vehicle is running, even if the vehicle body vibrates significantly due to rough roads or bumps. It is possible. Therefore, there is an advantage that there is no misadjustment of the vehicle height as in the conventional case.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of a vehicle height adjustment device for carrying out the method of the present invention, Figures 2 and 2 are flow charts showing the method of adjusting vehicle height of the present invention, Figures 3 and 4 are vehicle height values in vehicle height adjustment. Fig. 5 (α) (h) is an explanatory diagram showing the averaging processing method, Fig. 5 (α) (h) is an illustration of the conventional vehicle height adjustment while the vehicle is stopped, and Fig. 6 (α) (h) is an illustration of the vehicle height adjustment while the vehicle is running. It is a diagram. 1...Vehicle height sensor, 2...Compressor, 31.Exhaust valve, 4.1 Suspension.

Claims (1)

[Claims] In a vehicle height adjustment device that expands and contracts the suspension by selectively controlling a compressor or exhaust valve to maintain an appropriate vehicle height based on the output of a vehicle height sensor, there are two steps: sampling the vehicle height value at regular intervals; a step of averaging the sampled vehicle height values at regular intervals when the vehicle exceeds the appropriate vehicle height; a step of comparing the averaged vehicle height value with a preset appropriate vehicle height value; and a step of comparing the averaged vehicle height value with a preset appropriate vehicle height value. 1. A vehicle height adjustment method comprising the step of selectively controlling a compressor or an exhaust valve depending on the size of the vehicle height.