JPS6350207B2 - - Google Patents

Description

[Detailed description of the invention]

[Object of the invention] (Industrial application field) The present invention relates to height control of a vehicle body, and in particular, detects the height of the vehicle body with a vehicle height detector, and controls vehicle height adjustment means in accordance with the detected vehicle height. The present invention relates to adjusting the height of a vehicle to keep the vehicle height within a predetermined range. (Prior Art) In this type of vehicle height adjustment, for example, as disclosed in U.S. Pat. No. 4,105,216, a vehicle height detector detects a vehicle height region, and a signal processing circuit processes a detection signal. to obtain a signal that energizes the vehicle height adjustment drive system, and sends this signal to the vehicle height control circuit, which lowers the fluid pressure in the suspension system when the vehicle height is "high" in the drive system, and lowers the fluid pressure when the vehicle height is "low". At certain times, the fluid pressure is increased. Therefore, in order to prevent repeated fluid pressure reduction operations when the detected vehicle height vibrates near the boundary between "medium" and "high", and when the detected vehicle height vibrates near the boundary between "medium" and "low", In order to prevent pressure-up operation, the vehicle height control circuit generally includes one set of rise delay circuits for the vehicle height "high" signal processing system and the vehicle height "low" signal processing system, respectively. The delay time is, for example, about 10 seconds. (Problem to be solved by the invention) If this delay time is short, the number of repetitions of vehicle height adjustment in response to bumps in the road or climbing and descending increases, resulting in poor vehicle height stability and frequent operation of the drive system. ,
If it is too long, the vehicle height will continue to shift for a long time, making it difficult to adjust the vehicle height. On the other hand, the height of the vehicle changes as people get on and off the vehicle and as cargo is loaded and unloaded, and it is preferable that the vehicle height be adjusted quickly at this time. An object of the present invention is to quickly adjust the vehicle height in response to changes in vehicle height caused by people getting on and off the vehicle. [Structure of the Invention] (Means for Solving the Problems) Since the door is opened and closed when a person gets on or off the vehicle, it can be determined that a person may get on or off the vehicle by opening or closing the door. Therefore, in order to achieve the above object, the present invention provides an adjusting means for adjusting the height of the vehicle body relative to the wheels; a vehicle height detecting means for generating a signal according to the height of the vehicle body; Vehicle height energizing control means for energizing the adjustment means to adjust the height of the vehicle body relative to the wheels to a target range after a delay time from when a change requiring vehicle height adjustment appears in the signal in response to the signal; In a vehicle height adjustment device comprising: door state detection means for detecting a change in the vehicle door from open to closed; Immediately after, a delay time adjusting means is provided to shorten the delay time of the vehicle height biasing control means. (Function) That is, a change from opening to closing of the door is detected, and immediately after this change occurs, the vehicle height adjustment delay time is set short. As a result, if someone gets on or off the vehicle, the vehicle height is quickly adjusted to the appropriate range. Even if there is no one getting in or out, when the door changes from open to closed, the vehicle is usually stopped or running at an extremely low speed, so even if the vehicle height adjustment delay time is set short immediately after that, as described above, It does not impair the stability of the vehicle height. Therefore, the vehicle height is adjusted to an appropriate range in response to changes in vehicle height due to people getting on and off the vehicle, and highly stable vehicle height adjustment is performed while the vehicle is running. Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings. (Embodiment) FIG. 1 shows how a vehicle height detector 100 used in an embodiment of the present invention is attached to a vehicle. The vehicle height detector 100 is fixed to the vehicle body frame 10, and one end of a link 20 is connected to its rotating shaft, and the other end of the link 20 is connected to the outer case of the differential gear 30. 40 is an axle. A cross-sectional view of the vehicle height detector 100 is shown in FIG. 2a.
In the vehicle height detector 100, the light shielding plate 1 has an arc-shaped fold 104 formed at the tip of the rotating shaft 103.
05 is fixed, and a link 20 is fixed to the other end. The base 106 has a printed circuit board 10
7 is fixed to the printed circuit board 107, and photo sensors 101 and 102 are fixed to this printed circuit board 107. 2b to 2d.
As shown in the figure. In addition, Fig. 2b shows the state of the vehicle height "high", Fig. 2c shows the state of the vehicle height "medium", and Fig. 2d shows the state of the vehicle height "medium".
The figure shows the vehicle height "low". The photo sensors 101 and 102 are composed of a light emitting diode and a photo transistor as shown in FIG.
The fold 104 of No. 5 cuts off. Outputs A and B of photo sensors 101 and 102 according to the vehicle height (3rd a)
Figure) is shown in Table 1 below.

[Table] FIG. 3a shows an embodiment of the present invention using the vehicle height detector described above. In this embodiment, the vehicle height adjustment control device is comprised of a clock pulse generator 210 and an energization control device 220. The clock pulse generator 210 is connected to a power source (+
V ₁ ) Delay circuit for closing detection (resistance Rd and capacitor Cd), inverter IN1, mono multivibrator MM1 for door close detection, pulse oscillator 2
11. Counter CO1 for frequency division, counter CO2 for time limit, and gate elements OR1, NA1 to NA3
It is made up of etc. In this clock pulse generator 210, when +V ₁ is applied to the resistor Rd by closing the ignition key switch, the inverter IN1 outputs one pulse (plus) when +V ₁ is applied.
will occur. The door switch 50 opens when the door is closed,
They are closed when the door is opened, and if at least one of them is closed (door open), the warning lamp 60 lights up. Mono multivibrator MM1
is the rise of the input from L (earth) to H (plus constant level), that is, the state change from open to closed of the door,
Since the mono-multivibrator MM1 generates one pulse (plus) when one door changes from open to closed, the mono-multivibrator MM1 outputs one pulse. The input/output timing of the clock pulse generator 210 is shown in FIG. 3b. The operation of the clock pulse generator 210 will be explained with reference to FIG. 3b.
When the power supply +V ₁ is turned on, a voltage is simultaneously applied to each of the circuit elements, and the oscillator 211 operates to generate a pulse f. This pulse f is applied to the counter CO1, which causes its Q ₀
A pulse with a period twice that of the pulse f is generated at the end, a pulse with a period eight times as long as the pulse f is generated at the _Q2 end, and a pulse with a period 16 times the period _Q3 is generated at the Q3 end, and while the power is on, i.e. While the ignition key switch is closed,
These pulses are output continuously. Counter CO2 counts the Q ₂ output pulses of counter CO1, but counts 8 pulses and outputs Q _3.
When the end reaches a high level H, the count up is stopped. Then, when the clear input terminal CLR becomes H, the clear state is entered. Therefore, the counter CO2 is
After the power is turned on (pulse b) or the vehicle door changes from open to closed, until the _Q2 end output pulse of CO1 is counted 8 times, the _Q3 end is set to L, and the
When counting is completed, the _Q3 end is set to H. The output L at the _Q3 end of counter CO2 is a significant signal,
While the output of _Q3 terminal is L, NAND gate NA2 is
Outputs the inverted pulse h of the Q ₀ end pulse of CO1,
When the output of _Q3 terminal becomes H, NAND gate NA1
Outputs the inverted pulse g of the _Q3 end pulse of CO1. As a result, as shown in FIG. 3b, the output i of the NAND gate NA3, that is, the output clock pulse of the device 210, is T ₀
(while the _Q3 end output of counter CO2 is a significant signal L), it becomes the output pulse of the _Q0 end of counter CO1, and after that, it becomes the output pulse of the _Q3 end of counter CO1 (the output pulse of the _Q0 end). (8 times the period). This output pulse i of NAND gate NA3 is
is applied to the bias control device 220. The energization control device 220 includes a Noah gate NR1, a counter CO3, AND gates A1 and A2, and an inverter IN2. Vehicle height detection signals A and B of the vehicle height detector 100 are applied to the Noah gate NR1, and the AND gates A1 and A2 are applied with signals A and B, respectively. These signals change depending on the vehicle height as shown in Table 1. Counter CO3 is clear while its clear input is at H. Since the NOR gate NR1 outputs the inversion of the logical sum of A and B (inversion of A+B), referring to Table 1, the counter CO3 indicates that the vehicle height is "medium".
is cleared, and the vehicle height is "high" (A=H)
Or when it becomes “low” (B=H), the clock pulse i
starts counting and is cleared when the vehicle height returns to "medium". When the counter CO3 counts eight clock pulses i, the _Q3 terminal changes from L to H, the output of the inverter IN2 changes from H to L, and the count stops. AND gate A1 has signal A and
Q ₃ terminal output, AND gate A2 has signal B and Q ₃
Since the end output is applied, if the vehicle height changes from "medium" to "high" and remains "high", the output of AND gate A1 will be output when 8 clock pulses i are counted from the change to "high". changes from L to vehicle height lowering instruction level H, which opens the relief valve 300, lowers the air pressure in the air chamber of the suspension system 500, and lowers the vehicle height. Signal A is H
When it changes from (“high”) to L (“low”), the counter CO3
is cleared, both inputs of AND gate A1 become L, and relief valve 300 is closed. When the vehicle height changes from "medium" to "low" (B=H) and remains "low", the output of AND gate A2 changes from L to "L" when 8 clock pulses i are counted from the change to "low". The vehicle height increase instruction level changes to H, which causes the motor energizing relay 403 to
is closed, the motor 401 rotates, the air compressor 402 is driven, and the air pressure in the air chamber of the suspension system 500 increases, raising the vehicle height. When signal B changes from H to L (vehicle height "low"), counter CO3 is cleared, so both inputs of AND gate A2 become L, relay 403 opens and compressor 402 stops. As described above, the clock pulse generator 210
gives a short-period pulse from power-on or door closing to T ₀ , and thereafter a long-period pulse of 8 times the period as clock pulse i to the energization control device 220, and the energization control device 220 controls the vehicle height. When the state changes from "medium" to "high" or "low", as long as that state continues, the vehicle height lowering instruction signal or vehicle height increasing instruction signal is output after a delay time Td of 8 counts of clock pulse i. After turning on the power or closing the door
Delay time Tds between T ₀ and delay time after T ₀ elapses
Tdr is Tds/Tdr = 1/8, and if the delay time Tdr during driving is, for example, 8 seconds, immediately after the power is turned on or the door is closed, when the vehicle height becomes "high" or "low", then Tds = 1 second. Control to set the vehicle height to ``medium'' is then started, and the vehicle height is automatically adjusted to the appropriate ``medium'' range much faster than before. FIG. 4 shows the configuration of a vehicle height adjustment control device 200 according to another embodiment of the present invention. In this, device 2
00 is composed of a timer 250 and an energizing control device 220. In the timer 250, the counter CO2 starts counting pulses f in response to turning on the power or closing the door, and when it counts 64 pulses, the output at the _Q6 terminal becomes H. In the embodiment of FIG. 3a, one pulse is generated at the _Q2 end of the counter CO1 every 8 periods of pulse f, and when the counter CO2 counts 8 _Q2 output pulses, the output at the _Q3 end becomes H. Therefore, also in the embodiment shown in FIG. 4, the _Q6 terminal of the counter CO2 becomes a significant signal L during _T0 (FIG. 3b) after the power is turned on or the door is closed. Biasing control device 2
20, counter CO3 counts pulses f, and outputs the _Q4 end of the counter CO3 during _T0 , and outputs the _Q7 end of the counter CO3 after _T0 to AND gate A1,
A2 and inverter IN2, and during _T0 , the delay time Tds is 16 times the pulse f.
count time, and the delay time after T ₀ elapses.
Tdr is the count time of 128 pulses f.
In the embodiment shown in FIG. 3a, the _counter is
Counter CO3 counts the Q ₀ end output pulse of CO1 (period twice the pulse f), and outputs the Q ₃ end output to AND gates A1, A2 and inverter IN.
2, the delay time Tds is 2× of the pulse f.
8=16 counting times. Therefore, the predetermined time T ₀ and the delay time Tds in the embodiment shown in FIG.
Tdr will be equal to those of the embodiment shown in FIG. 3a if the pulses f have the same period. FIG. 5a shows another embodiment of the invention. In this case, the vehicle height adjustment control device 200 is a one-chip microcomputer (hereinafter referred to as microcomputer).
It is composed of MPU. The ROM of the microcomputer MPU monitors the state of the vehicle height detector 100 and the door switch starting from the moment the power is turned on, and sets a short delay time for a predetermined time after the power is turned on or the door is closed. In other cases, program data for controlling the vehicle height by setting a longer delay time is stored. The control operation of the microcomputer MPU based on the program data is shown in FIG. 5b. In addition, in Figure 5b, the register refers to the MPU.
A timer refers to the execution of a program timer that counts a set number of clock pulses (or timing pulses). With reference to Figures 5a and 5b below,
The control operation of the MPU will be explained. First, the registers and memory contents shown in FIG. 5b are shown in Table 2 below.

〔Effect of the invention〕

As described above, in the present invention, the adjustment means 300, 401 to 403, which adjust the height of the vehicle body relative to the wheels,
500; Vehicle height detection means 100 that generates a signal according to the height of the vehicle body; and, in accordance with the signal generated by the vehicle height detection means 100, a delay time is calculated after a change in the signal indicating the need for vehicle height adjustment appears. In a vehicle height adjustment device comprising: vehicle height biasing control means 220, MPU; Door state detection means 50, MM1, which detects a change from open to closed;
MPU; and door state detection means 50, MM1,
Immediately after the MPU detects a change from opening to closing of the vehicle door, the vehicle height biasing control means 22
0, delay time adjusting means 210, 250, MPU;
In other words, by detecting the change from opening to closing of the door,
Immediately after this change occurs, the vehicle height adjustment delay time is set to be short, so if someone gets on or off the vehicle, the vehicle height is quickly adjusted to the appropriate range. Even if there is no one getting in or out, when the door changes from open to closed, the vehicle is usually stopped or running at an extremely low speed, so even if the vehicle height adjustment delay time is set short immediately after that, as described above, It does not impair the stability of the vehicle height. Therefore, the vehicle height can be adjusted to an appropriate range in response to changes in vehicle height due to people getting on and off, and while the vehicle is running, the vehicle height can be adjusted with a relatively long delay time with high stability. will be carried out.

[Brief explanation of the drawing]

FIG. 1 shows a vehicle height detector 1 in an embodiment of the present invention.
2a is a sectional view of the vehicle height detector 100. FIG. Figures 2b, 2c and 2d are cross-sectional views taken along the line -- in Figure 2a, respectively showing different operating states. FIG. 3a is a block diagram showing one embodiment of the present invention, and FIG. 3b is a time chart showing the timing of signals in each part thereof. FIG. 4 is a block diagram showing another embodiment of the present invention. FIG. 5a is a block diagram showing still another embodiment of the present invention, and FIG. 5b is a flowchart showing the control operation of the microcomputer MPU shown therein. 10: Body frame, 20: Link, 30: Differential gear, 40: Axle, 50: Door switch, MM1: Mono multivibrator (5
0, MM1: door condition detection means), 60: warning lamp, 100: vehicle height detector (vehicle height detection means), 101, 102: photo sensor, 103:
Rotation axis, 104: Folding of light shielding plate 105, 20
0: vehicle height adjustment control device, 210: clock pulse generator (delay time adjustment means), 220: energizing control device (vehicle height energizing control means), 230, 240:
Connector, 250: Timing device (delay time adjustment means), 300: Relief valve, 401: Motor,
402: Compressor, 403: Relay, 50
0: Suspension device, 300,401-403,50
0: Adjustment means, MPU: Microcomputer (vehicle height bias control means, delay time adjustment means), 50,
MPU: Door status detection means.

Claims (1)

[Claims] 1. Adjustment means for adjusting the height of the vehicle body relative to the wheels; Vehicle height detection means for generating a signal according to the height of the vehicle body; and A vehicle height adjustment device comprising: vehicle height biasing control means for biasing the adjustment means so as to adjust the height of the vehicle body relative to the wheels to a target range after a delay time after a change indicating the need for vehicle height adjustment appears in the signal; In: door state detection means for detecting a change in the vehicle door from open to closed; and, in response to the door state detection means detecting a change in the vehicle door from open to closed; A vehicle height adjustment device comprising: delay time adjustment means for shortening the delay time of the force control means.