JPH09207535A - Car height adjusting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid rapid change of car height when a car is going to start. SOLUTION: The standard car height hH is itself used as the target car height hT while a car is running (Step 120), and at a standstill, the value obtained from the given formula is used as target car height hT (Step 130). Accordingly the target car height at a standstill is nearer the sensed car height hi than the target car height during running in an amount calculated from (standard car height hH - sensed car height hi) *a. Accordihgly the car height difference 4h between the sensed car height hi and target car height hT as target for car height adjustment is lessened, and the amount of car height adjustment made by wheel suspension devices for nullifying ▵h is corrected decrementally from the case in which the car is running.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle height adjusting device for adjusting a vehicle height by controlling expansion and contraction of an actuator interposed between a vehicle body and wheels.

[0002]

2. Description of the Related Art This type of vehicle height adjusting device is used for various purposes. For example, when the vehicle reaches a high-speed running state of 80 km / h or more, its vehicle height is made lower than that at a normal speed to ensure running stability, or the vehicle height is kept constant regardless of changes in the number of occupants and the weight of the load. In addition, when the passenger gets on and off, the vehicle height is made lower than the vehicle height during traveling to improve the getting on / off property. In these cases, the actuator is controlled to expand and contract so that the current vehicle height of the vehicle (hereinafter referred to as the current vehicle height) matches the target vehicle height according to various situations. The expansion / contraction control of the actuator is started so that the current vehicle height matches the target vehicle height when the vehicle height difference between the current vehicle height and the target vehicle height exceeds a certain value.

It has also been proposed to control the actuator expansion / contraction in accordance with the running state of the vehicle, rather than uniformly controlling the actuator expansion / contraction so that the current vehicle height matches the target vehicle height. For example, JP-A-63-19910
9 proposes a technique in which the vehicle height difference that determines the start timing of expansion / contraction control of the actuator is set to a different value between when the vehicle is stopped and when the vehicle is running, and the frequency of expansion / contraction control of the actuator is reduced when the vehicle is stopped.

[0004]

However, in the conventional vehicle height adjusting device, the following problems remain unsolved.

Since the vehicle body is in contact with the road surface through its wheels and the vehicle body is suspended by the actuator, a reaction force is applied to the actuator from the road surface through the wheels (hereinafter, the reaction force acting on the actuator is reflected by the road surface reaction). Power). On the other hand, when the actuator is expanded and contracted to adjust the vehicle height, the wheelbase and tread of the vehicle change due to the change in vehicle height due to the suspension structure of the vehicle. The degree of change at this time depends on the suspension structure (for example, a mechanical structure such as a link type suspension, a parallel leaf type suspension, a swing accelerator type suspension, a trailing arm type suspension, etc.) and the supply and discharge of fluid such as air. Air suspension etc.). The vertical movement of the vehicle through the expansion and contraction of the actuator and the change behavior of the wheelbase and tread that accompanies the expansion and contraction of the actuator are caused by the expansion and contraction of the actuator.

By the way, the road surface reaction force naturally changes according to the condition of the road surface, but also changes under the same road condition depending on the running condition of the vehicle. More specifically, the contact state between the wheel and the road surface depends on whether or not the wheel is rotating, when the vehicle is parked and stopped (the vehicle is stopped) and when the wheel is running. Different,
Friction forces generated in the left-right wheel direction and the front-rear wheel direction are different between the wheel and the road surface. And when parking or stopping, the frictional force in both directions increases due to the fact that the wheels are not rotating,
Road reaction force also increases accordingly.

Therefore, when the actuator is controlled to expand or contract to match the current vehicle height with the target vehicle height when the vehicle is parked or parked, the road surface reaction force prevents the vertical movement of the vehicle height through the expansion and contraction of the actuator and the change of the wheel base and tread. Becomes Therefore, even though the actuator is controlled according to the vehicle height difference between the current vehicle height and the target vehicle height, the vehicle height, the wheel base, and the tread may not change in accordance with the control amount. When the vehicle starts from such a situation, the road surface reaction force decreases almost at the same time as the vehicle starts, and the vehicle height and the wheel base and tread suddenly change to those that match the control amount of the actuator, causing shock and discomfort to the occupants. give.

As proposed in Japanese Unexamined Patent Publication No. 63-199109, even if the frequency of extension / contraction control of the actuator when the vehicle is stopped is reduced, if the extension / contraction control of the actuator is executed when the vehicle is stopped, The vehicle height and other factors suddenly change when the vehicle is started, and the passengers are still shocked and uncomfortable.

Further, if the expansion / contraction control of the actuator is continued until the current vehicle height and the target vehicle height match, the control becomes excessive, and the vehicle height drastically changes from the target vehicle height when the vehicle starts, and both vehicle heights match. A new control is required for starting the vehicle. Therefore, the occupant may feel a shock or a sense of discomfort even if the vehicle height changes due to the new control.

The present invention has been made to solve the above problems, and it is an object of the present invention to avoid a sudden change in vehicle height during vehicle height adjustment through expansion / contraction control of an actuator.

[0011]

In order to solve such a problem, the vehicle height adjusting device of the first invention is interposed between a vehicle body and a wheel to suspend the vehicle body and expand and contract. The actuator configured to be possible and the vehicle height,
A vehicle height adjusting device comprising a control means for controlling expansion and contraction of the actuator on the side that matches the commanded target vehicle height, wherein the control means is characterized in that the reaction force acting from the road surface through the wheel through the actuator is the above-mentioned. Under a situation in which the actuator is prevented from expanding and contracting, it has means for reducing and correcting the expansion and contraction control amount of the actuator for matching the vehicle height with the commanded target vehicle height.

In the vehicle height adjusting device of the first invention having the above-mentioned structure, the reaction force acting on the actuator from the road surface acts on the side which hinders the expansion and contraction of the actuator (specifically, the vehicle is in a stopped state). In the situation), since the expansion / contraction control amount of the actuator is corrected to be reduced, the vehicle height adjustment amount is reduced in such a situation. Therefore, the amount of change in vehicle height when the vehicle is out of the situation (specifically, when the vehicle is started) can be reduced, so that the occupant is not shocked or feels strange.

Further, the vehicle height adjusting device of the second aspect of the invention is provided with an actuator which is interposed between the vehicle body and the wheels to suspend the vehicle body so as to extend and contract, and a vehicle height of the vehicle. A vehicle height adjusting device comprising a control means for controlling expansion and contraction of the actuator on the side that matches the target vehicle height,
In a situation where the reaction force acting on the actuator from the road surface through the wheels acts on the side that hinders expansion and contraction of the actuator, the control means makes the commanded target vehicle height close to the current vehicle height of the vehicle. It has means for changing the target vehicle height.

In the vehicle height adjusting device of the second aspect of the present invention having the above structure, the reaction force acting on the actuator from the road surface acts on the side that impedes expansion and contraction of the actuator (specifically, the vehicle is in a stopped state). In the situation), the target vehicle height itself is changed to a value close to the current vehicle height of the vehicle at that time, so that the vehicle height adjustment amount is also reduced. Therefore, the amount of change in vehicle height when the vehicle is out of the situation (specifically, when the vehicle is started) can be reduced, so that the occupant is not shocked or feels strange.

[0015]

Other Embodiments of the Invention The present invention can also adopt the following other embodiments. In the first embodiment, the vehicle body is suspended between the vehicle body and the wheels to suspend and extend the vehicle body. A vehicle height adjusting device comprising an actuator configured as possible and a vehicle height of the vehicle on a side that matches a commanded target vehicle height, and a control means that controls expansion and contraction of the actuator, wherein the control means A means for obtaining a vehicle height difference between the commanded target vehicle height and the current vehicle height of the vehicle, and a situation in which a reaction force acting on the actuator from the road surface through the wheels acts on the side that prevents expansion and contraction of the actuator. Then, a vehicle height adjusting device having means for reducing and correcting the obtained vehicle height difference, and means for controlling expansion / contraction of the actuator on the side where the reduced and corrected vehicle height difference is eliminated.

In the first aspect, the command is issued under the situation where the reaction force acting on the actuator from the road surface acts on the side that hinders the expansion and contraction of the actuator (specifically, under the situation where the vehicle is stopped). The vehicle height difference between the target vehicle height and the current vehicle height of the vehicle is reduced and corrected, and the actuator is extended / contracted to the side where the reduced and corrected vehicle height difference is eliminated. Therefore,
As a result, the amount of expansion and contraction control of the actuator is reduced,
The vehicle height adjustment amount is also small. Therefore, even the vehicle height adjusting device of the first aspect can reduce the amount of change in the vehicle height when the vehicle is out of the situation (specifically, when the vehicle is started), so that the occupant may feel a shock or a sense of discomfort. Never give.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a vehicle height adjusting device according to the present invention will be described based on an embodiment. FIG. 1 is a block diagram schematically showing the entire vehicle height adjusting device 10 of the embodiment.

As shown in the figure, the vehicle height adjusting device 10 corresponds to the left front wheel WFL, the right front wheel WFR, the left rear wheel WRL, and the right rear wheel WRR, respectively.
L, 11FR, 11RL, 11RR). In the following description, the subscript i is attached to each wheel.
FL, FR, RL and RR are arbitrarily represented.

The suspension device 11i includes a shock absorber 12i provided between each wheel and the vehicle body,
The air suspension includes an air chamber 13i. The shock absorber 12i can change the damping force for vertical movement of the vehicle body in three stages (small, medium, large) according to the valve opening controlled by an actuator (not shown).

A supply / discharge device 14 for supplying / discharging air is connected to the air chamber 13i. This feeding / discharging device 14
Is a compressor 16 driven by an electric motor 15.
It has. This compressor 16 is provided with an air chamber 13 via a first electromagnetic switching valve 17i provided for each wheel.
connected to i. These first electromagnetic switching valves 17i
Is normally turned off and turned on by energization to allow each communication with each air chamber 13i. Also,
A second electromagnetic switching valve 18 is connected to the compressor 16, and the second electromagnetic switching valve 18 is normally in an off state and is turned on by energization to communicate with the atmosphere.

A vehicle height sensor 20i is incorporated in each suspension device 11i, and the left front wheel W is provided.
An electronic control unit detects a vehicle height representing the distance to the road surface of the vehicle body at each position of FL, right front wheel WFR, left rear wheel WRL, and right rear wheel WRR, and outputs a detection signal corresponding to the detected vehicle height hi. Output to 30.

The electronic control unit 30 includes a CPU, ROM, R
It is composed of a microcomputer having an AM, a timer, etc., takes in signals from the vehicle height sensor 20i, the vehicle speed sensor 25, etc., and is necessary for adjusting the vehicle height to the first electromagnetic switching valve 17i, the second electromagnetic switching valve 18 and the electric motor 15. Various drive signals are output and vehicle height adjustment processing is executed. Further, the electronic control unit 30 is connected to a brake switch 26 that issues a signal necessary for vehicle height adjustment, a shift sensor 27, and a vehicle height setting switch 28, respectively.

The brake switch 26 outputs a brake ON signal when a foot brake (not shown) is stepped on, and the shift sensor 27 outputs a signal corresponding to the operation position of a shift lever (not shown), such as a parking range (P range). The signal of is output. The vehicle height setting switch 28 is operated by an occupant, and sets the vehicle height level to HIGH, NORMAL, or LOW according to the operated position, and outputs the signal. The vehicle height set by the vehicle height setting switch 28 is a standard vehicle height that is desirable to maintain the vehicle height of the vehicle at the set vehicle height. If the vehicle height change switch 28 is used as a vehicle height change mode setting switch and the HIGH mode is selected, the vehicle height is set to H during normal traveling.
The NORMAL signal is output to the IGH during high-speed driving, and NOR
If MAL mode is selected, the vehicle height is NORMAL during normal driving.
It can also be configured to output a LOW signal when driving at high speed. In this case, the standard vehicle height is set to HIGH, NORMAL, or LOW according to the vehicle speed.

In the vehicle height adjusting device 10 as described above, when the vehicle height of each wheel is increased, the electric motor 15 is driven to operate the compressor 16 and the second electromagnetic switching valve 1 is operated.
8 is closed, and one of the first electromagnetic switching valves 17i is opened. As a result, the air pressure-fed from the compressor 16 reaches any one of the air chambers 13i via one of the first electromagnetic switching valves 17i, and the air chamber 13i
The air volume of i is increased to increase the vehicle height corresponding to that wheel.

On the other hand, when maintaining the vehicle height, the compressor 16 is stopped and the first electromagnetic switching valve 17i is closed. Further, when lowering the vehicle height, the first electromagnetic switching valve 17i is opened and the second electromagnetic switching valve 18 is opened. As a result, the compressed air in the air chamber 13i is released to the atmosphere via the first electromagnetic switching valve 17i and the second electromagnetic switching valve 18, and the air volume in the air chamber 13i is reduced, so that the air in the wheel is reduced. Lower the vehicle height at the corresponding position.

Next, the vehicle height adjustment processing executed by the electronic control unit 30 will be described with reference to the flowchart of FIG. The vehicle height adjustment processing shown in this flowchart is repeatedly executed at predetermined time intervals after initialization of various flags is executed. The vehicle height adjustment by this vehicle height adjustment processing is simultaneously performed for each of the left front wheel WFL, the right front wheel WFR, the left rear wheel WRL, and the right rear wheel WRR in order to quickly set the vehicle height to the target vehicle height.

When the vehicle height adjusting process is started, first,
The various sensors and switches described above are scanned to read signals required for vehicle height adjustment (step S100). The signal read in this step S100 is the vehicle speed sensor 25.
From the vehicle speed (detected vehicle speed) or the vehicle height hi detected from the vehicle height sensor 20i (that is, the left front wheel vehicle height hFL, the right front wheel vehicle height hFR,
In addition to the left rear wheel vehicle height hRL and the right rear wheel vehicle height hRR), a signal regarding the presence or absence of a foot brake from the brake switch 26, a shift position signal from the shift sensor 27,
The vehicle height setting signal from the vehicle height setting switch 28 and the like.

Subsequent to the sensor scan, the standard vehicle height hH is set (step S110) and whether or not the vehicle is in a stopped state is determined (step S115) on the basis of the read various signals. To do. Standard vehicle height hH
Is determined by the vehicle speed and the vehicle height setting signal from the vehicle height setting switch 28. Whether or not the vehicle is in a stopped state is determined by the foot brake ON signal from the brake switch 26 or the P range signal from the shift sensor 27. It depends on the presence or absence. The foot brake ON signal and the P range signal determine whether the vehicle is stopped by the foot brake or the P range.

In this case, in step S115, it is sufficient to determine whether or not the vehicle is in a stopped state by either the foot brake ON signal or the P range signal.
It is not necessary to judge that the vehicle is in a stopped state only when both signals are input. In addition, the suspension device 1
When the vehicle height is adjusted by 1i, the signal used for determining the stopped state can be changed due to the suspension structure (the air suspension in this embodiment). That is, when the vehicle height adjustment is performed and the tread change is more remarkable than the wheel base change, when the vehicle speed sensor 25 detects zero vehicle speed depending on the presence or absence of the P range signal from the shift sensor 27. If it is determined whether the vehicle is in a stopped state and the wheelbase change is more noticeable than the tread change, whether the vehicle is in a stopped state depends on the presence or absence of a foot brake ON signal from the brake switch 26. Step S1 to make a decision
The processing content of 15 can be changed.

If a negative determination is made in step S115, the vehicle is running, so the standard vehicle height hH set in step S110 is set as the target vehicle height hT (step S11).
120). That is, if the vehicle is running, the target vehicle height hT (= standard vehicle height hH) is determined by the vehicle speed and the vehicle height setting signal from the vehicle height setting switch 28 at that time.

On the other hand, when it is determined in step S115 that the vehicle is stopped, the standard vehicle height hH and the detected vehicle height hH
The target vehicle height h according to the following equation using i (current vehicle height)
T is set (step S130).

Target vehicle height hT = {standard vehicle height hH− (standard vehicle height hH−detected vehicle height hi) * a} Equation (1)

The constant a in this equation (1) is 0 <a <
The suspension device 11i is a constant whose value satisfies 1.
It depends on the suspension structure.

Here, the relationship between the target vehicle height hT determined by the equation (1) and the detected vehicle height hi will be described.

As described above, in step S120, which is performed during traveling, the standard vehicle height hH itself is the target vehicle height hH.
On the other hand, the target vehicle height hT is obtained by subtracting the value calculated by (standard vehicle height hH-detected vehicle height hi) * a from the standard vehicle height hH in step S130 when the vehicle is stopped. It Therefore, when the detected vehicle height hi is lower than the standard vehicle height hH, the vehicle height (calculated value which is lower than the standard vehicle height hH by the value calculated by (standard vehicle height hH-detected vehicle height hi) * a. ) Is the target vehicle height hT. When the detected vehicle height hi is higher than the standard vehicle height hH, (standard vehicle height hH − detected vehicle height hH
Since the value calculated in i) is negative, (standard vehicle height hH-
The detected vehicle height hi) * a is higher than the standard vehicle height hH by the absolute value of the value calculated (the calculated value) is the target vehicle height hT.
It is said. In other words, when stopped, the suspension device 1
The target vehicle height hT to be matched by 1i is set to a vehicle height approaching the detected vehicle height hi at the time of the stop, and the vehicle height difference Δh between the target vehicle height hT and the detected vehicle height hi becomes small.

In this case, the detected vehicle height hi is left front wheel vehicle height hFL, right front wheel vehicle height hFR, left rear wheel vehicle height hRL and right in the present embodiment because of the fact that the vehicle height control is performed simultaneously for the front and rear wheels. It is the average value of the rear wheel height hRR.

Then, the above-mentioned steps S120, 13
Following the setting of the target vehicle height hT at 0, it is determined whether or not the detected vehicle height hi matches the target vehicle height hT (step S135), and if a positive determination is made, it is determined that vehicle height adjustment is not necessary. The process moves to step S100 described above. On the other hand, when it is determined in step S135 that the detected vehicle height hi is different from the target vehicle height hT, the vehicle height difference Δh between the target vehicle height hT and the detected vehicle height hi is calculated, and the vehicle height difference Δh is calculated. The vehicle height is adjusted so that the detected vehicle height hi matches the target vehicle height hT set in steps S120 and S130 (step S140).

More specifically, when the detected vehicle height hi is lower than the target vehicle height hT, the compressor 16 is operated, the second electromagnetic switching valve 18 is closed, and the first electromagnetic switching valve 17i is turned on. This is done by opening the valve. As a result, compressed air is sent from the compressor 16 into the air chamber 13i of the suspension device 11i for each wheel, and the vehicle height is adjusted. In this case, the valve opening time of the first electromagnetic switching valve 17i is determined according to the vehicle height difference Δh, and a map stored in advance in RAM in association with the vehicle height difference Δh is referred to.

On the other hand, when the detected vehicle height hi is higher than the target vehicle height hT, the compressor 16 is stopped, the second electromagnetic switching valve 18 is opened, and the first electromagnetic switching valve 17i is opened. As a result, the compressed air in the air chamber 13i of the suspension device 11i for each wheel is released to the atmosphere, and the vehicle height lowering control is executed. The valve opening time of the first electromagnetic switching valve 17i in this case is also determined according to the map and the vehicle height difference Δh.

Then, in step S135, the detected vehicle height hi is detected.
When it is determined that the target vehicle height hT is equal to the target vehicle height hT, the compressor 16 is stopped and the second electromagnetic switching valve 18 and the first electromagnetic switching valve 17i are closed. In this case, since the compressed air in the air chamber 13i is maintained as it is, the vehicle height is not adjusted and the vehicle height is maintained. The determination as to whether the detected vehicle height hi matches the target vehicle height hT is made when the detected vehicle height hi is within a predetermined range (target vehicle height hT ± e) around the target vehicle height hT. .

As explained above, in the vehicle height adjusting device of this embodiment, different target vehicle heights hT are set depending on whether the vehicle is running or not.
When the vehicle is stopped, the target vehicle height hT is set to the vehicle height that is close to the detected vehicle height hi at the time of the stop. As a result, when stopped, the target vehicle height h, which is the target for vehicle height adjustment,
The vehicle height difference Δh between T and the detected vehicle height hi becomes smaller, and the vehicle height adjustment amount of each wheel by the suspension device 11i is corrected to be smaller than that when the vehicle is traveling.

Therefore, the road surface reaction force acting from the road surface through the wheels to the air chamber 13i, which is an actuator for adjusting the vehicle height, acts on the side that hinders the expansion and contraction of the air chamber 13i, that is, the vehicle is in a stopped state. Under the circumstances, the vehicle height adjustment amount is reduced by decreasing the vehicle height difference Δh, so that when the vehicle starts, the vehicle height change amount caused by the reduction of the road surface reaction force can be reduced. Therefore, according to the vehicle height adjusting device 10 of the present embodiment, the occupant is not shocked or uncomfortable.

After starting the vehicle, the standard vehicle height hH corresponding to the speed of the vehicle is set as the target vehicle height hT (step S120), and the vehicle height is quickly adjusted to the standard vehicle height hH.
Therefore, the occupant will not be shocked or feel uncomfortable even after the vehicle has started.

Further, in setting the target vehicle height hT when the vehicle is stopped, the detected vehicle height h when the vehicle is stopped is set.
Since i is reflected (equation (1)), more precise vehicle height adjustment can be performed, and shock and discomfort can be reliably eliminated.

The embodiments of the present invention have been described above.
The present invention is not limited to the above-described examples and embodiments at all, and it goes without saying that the present invention can be implemented in various modes without departing from the gist of the present invention. For example, the following modifications are possible.

In the above embodiment, the vehicle height is adjusted to be increased / decreased by supplying / discharging air to / from the air chamber in the air suspension. However, the present invention is not limited to this, and an actuator for changing the distance between the vehicle body and the wheels may be used. For example, a fluid source or a mechanical source can be used.

Further, although the description has been given of the case where the vehicle heights of the front and rear wheels are simultaneously adjusted, the present invention is not limited to this, and the vehicle heights can be adjusted separately for the left and right front wheels and the left and right rear wheels. The vehicle height may be adjusted independently for each wheel. In this case, in the former configuration, the front wheel and the rear wheel have different air supply / discharge systems, and in the latter configuration, the air supply / discharge system may be provided for each wheel. Further, the vehicle height can be adjusted only by either the left and right front wheels or the left and right rear wheels.

Further, in the above embodiment, when obtaining the vehicle height adjustment amount in the stopped state of the vehicle, the vehicle height adjustment is performed by setting the target vehicle height hT so that the vehicle height difference Δh from the detected vehicle height hi becomes small. Although the amount of the vehicle height adjustment is reduced and corrected, the vehicle height adjustment amount may be directly reduced and corrected. More specifically, the target vehicle height hT is the same when the vehicle is stopped and when the vehicle is running.
The vehicle height difference Δh obtained from the target vehicle height hT and the detected vehicle height hi may be corrected to be reduced when the vehicle is stopped. Any method may be used to correct the decrease in the vehicle height difference Δh. For example, it is possible to uniformly correct the decrease or use a map corresponding to the vehicle height when the vehicle is stopped.

[Brief description of drawings]

FIG. 1 is a block diagram schematically showing an entire vehicle height adjusting device 10 according to an embodiment.

FIG. 2 is a flowchart showing a vehicle height adjustment process executed by an electronic control unit 30 of the vehicle height adjustment device 10.

[Explanation of symbols]

 10 ... Vehicle height adjusting device 11i ... Suspension device 12i ... Shock absorber 13i ... Air chamber 14 ... Supply / discharge device 15 ... Electric motor 16 ... Compressor 17i ... First electromagnetic switching valve 18 ... Second electromagnetic switching valve 20i ... Vehicle height sensor 25 ... Vehicle speed sensor 26 ... Brake switch 27 ... Shift sensor 28 ... Vehicle height setting switch 30 ... Electronic control device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaro Tabata 1 Toyota-cho, Toyota-shi, Aichi Toyota Automobile Co., Ltd.

Claims (3)

[Claims] 1. An actuator, which is interposed between a vehicle body and a wheel, suspends the vehicle body and is configured to be extendable and retractable, and a vehicle height of the vehicle that matches a commanded target vehicle height,
A vehicle height adjusting device comprising: a control means for controlling the expansion and contraction of the actuator, wherein the control means is under a situation in which a reaction force acting from the road surface through the wheel to the actuator acts on a side that prevents expansion and contraction of the actuator. A vehicle height adjusting device comprising means for reducing and correcting an expansion / contraction control amount of the actuator for matching the vehicle height with the commanded target vehicle height. 2. An actuator, which is interposed between a vehicle body and a wheel, suspends the vehicle body and is configured to be extendable and retractable, and a vehicle height of the vehicle that matches a commanded target vehicle height,
A vehicle height adjusting device comprising: a control means for controlling the expansion and contraction of the actuator, wherein the control means is under a situation in which a reaction force acting from the road surface through the wheel to the actuator acts on a side that prevents expansion and contraction of the actuator. A vehicle height adjusting device comprising means for changing the commanded target vehicle height to a target vehicle height close to the current vehicle height of the vehicle. 3. The vehicle height adjusting device according to claim 1, wherein the control unit determines whether the vehicle is in a stopped state, and when the vehicle is in the stopped state, the reaction force is the It has a means for judging that it is in a situation where it acts on the side that prevents expansion and contraction of the actuator.