Vehicle height adjusting device

Abstract

The present application is to solve the problem of automatically and smoothly supplying air to an air suspension at a prescribed timing in either a natural vehicle height state or a vehicle height compressed state. To solve the above problem, the present application provides a vehicle height adjusting device mounted on a vehicle equipped with an air suspension. The vehicle height adjusting device is provided with a vehicle height sensor, an air pressure sensor, and an air control unit. The vehicle height sensor acquires a measured value of the vehicle height of the vehicle, that is, a measured vehicle height. The air pressure sensor acquires a measured value of the air pressure in the air suspension, that is, a measured air pressure. The air control unit performs a prescribed air supply control at each prescribed timing. In the air supply control, an air supply to the air suspension is attempted to be performed so that the measured vehicle height becomes a prescribed target vehicle height, and in a case where the measured vehicle height does not satisfy the target vehicle height for a prescribed period or more, an air supply is performed so that the measured air pressure becomes a prescribed target air pressure.

Description

Technical Field

[0001] This invention relates to a vehicle height adjustment device for adjusting vehicle height. Background Technology

[0002] Some vehicles are equipped with air suspension that uses air pressure to absorb impacts from the road surface.

[0003] [Previous Technical Documents]

[0004] (Patent Documents)

[0005] Patent Document 1: Japanese Patent Application Publication No. 2008-94301 Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] The inventors have noticed that the following problems may occur when transporting these vehicles by means of transport such as trailers or transport ships. When the transport period is long, the vehicle height decreases as air is gradually expelled from the air suspension. Consequently, when unloading the vehicle relative to the transport vehicle, the lower surface of the vehicle body tends to come into contact with the floor at the beginning and end of the slope. Furthermore, when the vehicle body is secured to the floor of the transport vehicle using ropes or straps, the tension applied to the vehicle body relative to the transport vehicle may loosen if the vehicle height decreases in this manner.

[0008] Therefore, the inventors first explored the configuration of the vehicle height measuring sensor and air control unit shown below. The vehicle height measuring sensor measures the vehicle height. The air control unit replenishes air to the air suspension at a predetermined time, so that the measured vehicle height obtained by the vehicle height sensor becomes the predetermined target vehicle height. According to this configuration, even in the case of long transportation periods, air can be automatically replenished to the air suspension at a predetermined time to restore the vehicle height to the target vehicle height.

[0009] However, the inventors have also noted the following potential problems. As mentioned earlier, when transporting vehicles, the vehicle body is sometimes secured to the floor of the transport vehicle using ropes or straps. In this case, the vehicle becomes in a "vehicle height compression state," meaning the air suspension is compressed and the vehicle height is compressed.

[0010] Under this high compression state, even if air is added to the air suspension, only the air pressure in the air suspension increases, and the tension of the restraints against this air pressure strengthens, but the vehicle height hardly increases. Therefore, the aforementioned control—that is, the control to add air to make the measured vehicle height become the target vehicle height—cannot function smoothly. Consequently, air cannot be added smoothly.

[0011] The present invention was made in view of the above circumstances, and its purpose is to enable the air suspension to be automatically and smoothly replenished at a predetermined time in any state other than the aforementioned vehicle height compression state, that is, in either the natural vehicle height state or the vehicle height compression state.

[0012] [Technical means to solve the problem]

[0013] The inventors discovered that the above-mentioned objective can be achieved by replenishing air to the air suspension according to prescribed rules, thus completing the present invention. The present invention is the following vehicle height adjustment device (1) to (5).

[0014] (1) A vehicle height adjustment device, mounted on a vehicle equipped with air suspension, and comprising:

[0015] The vehicle height sensor obtains the measured value of the vehicle height, which is the vehicle height measurement.

[0016] An air pressure sensor acquires the measured value of the air pressure within the aforementioned air suspension, which is equivalent to measuring the air pressure; and,

[0017] The air control department performs prescribed air replenishment control at designated times; and...

[0018] In the aforementioned air replenishment control, an attempt is made to replenish the air suspension to make the aforementioned measured vehicle height become the specified target vehicle height. If the aforementioned measured vehicle height does not meet the aforementioned target vehicle height for a specified period of time, the aforementioned air replenishment is performed to make the aforementioned measured air pressure become the specified target air pressure.

[0019] According to this design, air replenishment control attempts to replenish air to bring the measured vehicle height to the target vehicle height. Therefore, under the natural vehicle height condition, the vehicle height can be automatically restored to the target vehicle height through air replenishment control at a predetermined time.

[0020] On the other hand, under conditions of vehicle height compression, even if air is added to the air suspension, only the air pressure increases, and the vehicle height hardly increases. Therefore, the measured vehicle height may not meet the target height after a specified time. In this case, air is added to bring the measured air pressure to the target air pressure. Thus, under conditions of vehicle height compression, the air pressure can be automatically restored to the target air pressure through controlled air addition at predetermined times.

[0021] In summary, based on this structure, air can be automatically and smoothly replenished to the air suspension at a specified time, whether in the natural vehicle height state or the vehicle height compression state.

[0022] (2) According to the vehicle height adjustment device described in (1) above, the aforementioned air control unit is configured to be able to switch between a transport mode in which the aforementioned air replenishment control is performed at the aforementioned specified time and a normal mode in which the aforementioned air replenishment control is not performed at the aforementioned specified time.

[0023] According to this structure, by setting it to transport mode when transporting vehicles and otherwise to normal mode, air replenishment control can be performed only when transporting vehicles at specified times.

[0024] (3) According to the vehicle height adjustment device described in (2) above, there are multiple specified times.

[0025] In the aforementioned transportation mode, after the aforementioned air replenishment control is completed, the aforementioned air replenishment control is performed again with the specified replenishment interval as a trigger, thereby performing the aforementioned air replenishment control at each of the aforementioned specified times.

[0026] According to this construction, air can be efficiently replenished to the air suspension at each specified time.

[0027] (4) The vehicle height adjustment device according to (2) or (3) above, wherein the aforementioned air control unit,

[0028] The operation of selecting the aforementioned transportation mode will switch to the aforementioned transportation mode.

[0029] Under the aforementioned transportation mode, regardless of whether the operation that enables the vehicle to move (vehicle ON operation) or the operation that disables the vehicle to move (vehicle OFF operation) is performed, the transportation mode continues.

[0030] Switching to the aforementioned normal mode based on the operation of selecting the aforementioned normal mode.

[0031] According to this structure, since the transport mode continues regardless of vehicle ON or OFF operations, there is no need to worry about the transport mode being deactivated even when vehicle ON or OFF operations are performed for loading or unloading vehicles relative to the transport means. On the other hand, since the normal mode is switched based on the operation of selecting the normal mode, the normal mode can be quickly restored after the vehicle is unloaded from the transport means.

[0032] (5) The vehicle height adjustment device according to any one of (2) to (4) above, wherein, in the above transportation mode, the height higher than the above vehicle height in the above conventional mode is set as the above target vehicle height.

[0033] When using ramps to load or unload vehicles relative to a transportation method, the lower surface of the vehicle body may easily come into contact with the floor surface at the start and end points of the ramp. For this reason, in this design, a target vehicle height higher than that in the conventional mode is set. Therefore, in transportation mode, the risk of the lower surface of the vehicle body contacting the floor surface can be reduced.

[0034] (The effect of the invention)

[0035] As described above, based on the structure described in (1), air can be automatically and smoothly replenished to the air suspension at a predetermined time in either the natural vehicle height state or the vehicle height compression state. Furthermore, based on the structures described in (2) to (5) of the aforementioned (1), each additional effect can be obtained. Attached Figure Description

[0036] Figure 1 This is a structural diagram illustrating the vehicle height adjustment device and its surroundings according to the first embodiment.

[0037] Figure 2 This is a flowchart illustrating an example of the air replenishment control process.

[0038] Figure 3 This is another flowchart illustrating the process of air replenishment control.

[0039] Figure 4 This is a diagram illustrating an example of transporting a vehicle at its natural vehicle height.

[0040] Figure 5 This is a diagram illustrating an example of transporting a vehicle under compressed conditions. Detailed Implementation

[0041] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to any of the following embodiments and may be implemented with appropriate modifications without departing from the spirit of the invention.

[0042] [First Implementation Method]

[0043] Figure 1 The vehicle height adjustment device 100 shown is mounted on a vehicle 120 equipped with air suspension 125. The vehicle height adjustment device 100 includes a vehicle height sensor 30, an air pressure sensor 50, and an air control unit 40.

[0044] The vehicle height sensor 30 acquires the measured value of the vehicle height H of the vehicle 120, which is also called "measured vehicle height Hm". The air pressure sensor 50 acquires the measured value of the air pressure P within the air suspension 125, which is also called "measured air pressure Pm". The air control unit 40 is configured to switch between a specified normal mode Mn and a specified transport mode Mt.

[0045] The air control unit 40 performs prescribed air replenishment control in transport mode Mt. Furthermore, after this air replenishment control is completed, it performs air replenishment control again after a prescribed replenishment interval, such as 2 days. Thus, in transport mode Mt, air replenishment control is performed at each prescribed time, such as once every 2 days.

[0046] In each air replenishment control, an attempt is made to replenish air to the air suspension 125 to bring the measured vehicle height Hm to the specified target vehicle height Ho. If the measured vehicle height Hm does not meet the target vehicle height Ho within a specified period, this air replenishment is performed to bring the measured air pressure Pm to the specified target air pressure Po.

[0047] On the other hand, the air control unit 40, in normal mode Mn, does not perform air replenishment control at a predetermined time as in this way.

[0048] Hereinafter, the operation that enables vehicle 120 to drive will be referred to as "vehicle ON operation". Specifically, for example, if vehicle 120 is an engine vehicle, the vehicle ON operation includes turning on the ignition switch (ON), and if vehicle 120 is an electric vehicle, the vehicle ON operation includes turning on the power to the drive motor (ON).

[0049] Furthermore, the operation that prevents vehicle 120 from moving will be referred to as "vehicle OFF operation" below. Specifically, for example, if vehicle 120 is an engine-powered vehicle, the vehicle OFF operation includes turning off the ignition switch; if vehicle 120 is an electric vehicle, the vehicle OFF operation includes turning off the power to the drive motor.

[0050] The air control unit 40 switches to transport mode Mt based on the user's selection of transport mode Mt. In transport mode Mt, a target vehicle height Ho is set to a height higher than the vehicle height Hn in normal mode Mn. In transport mode Mt, transport mode Mt continues regardless of whether the vehicle is ON or OFF. Furthermore, the air control unit 40 switches to normal mode Mn based on the user's selection of normal mode Mn.

[0051] The following is a more detailed description of this embodiment.

[0052] like Figure 1As shown, the air suspension 125 is provided for each wheel 126. An air pump 123 is provided on the vehicle 120. Air from the pump 123 is supplied to each air suspension 125 via a corresponding valve 124. The vehicle height adjustment device 100 automatically activates at predetermined times in transport mode Mt. The air control unit 40 controls the air supply by controlling the pump 123 and each valve 124.

[0053] Hereinafter, the following state will be referred to as "vehicle height compression state Sc", and the state is as follows: Figure 5 As shown, because the vehicle body 121 of the vehicle 120 is secured from below with ropes or straps, the air suspension 125 is compressed and the vehicle height H is compressed due to the external force on the vehicle body 121. Furthermore, this state other than the "vehicle height compression state Sc" is referred to as the "natural vehicle height state Sn".

[0054] Next, refer to Figure 2 An example of the air replenishment control process will be illustrated below. Furthermore, in the following examples, the "s" preceding the numbers is an abbreviation for "step".

[0055] In this example, firstly, in s1, the vehicle height sensor 30 measures the vehicle height H, thereby obtaining the measured vehicle height Hm. Next, in s2, the air control unit 40 determines whether the measured vehicle height Hm is less than the target vehicle height Ho. If a negative determination is made, i.e., the measured vehicle height Hm reaches the target vehicle height Ho, the process ends and the air replenishment control terminates. On the other hand, if a positive determination is made in s2, i.e., the measured vehicle height Hm does not reach the target vehicle height Ho, the process proceeds to s3.

[0056] In step s3, the air pressure sensor 50 measures the air pressure P of the air suspension 125, thereby obtaining the measured air pressure Pm. Then, in step s4, the air control unit 40 determines whether the measured air pressure Pm is less than the target air pressure Po. If a negative determination is made, i.e., the measured air pressure Pm reaches the target air pressure Po, the process ends and the air replenishment control terminates. On the other hand, if a positive determination is made in step s4, i.e., the measured air pressure Pm does not reach the target air pressure Po, the process proceeds to step s5.

[0057] In step s5, the air control unit 40 controls the pump 123 and valve 124 to replenish the air suspension 125 with a predetermined amount of air. After that, the process returns to step s1.

[0058] According to the above process, under the natural vehicle height Sn, due to the air replenishment in s5, while the vehicle height H increases, the air pressure P hardly increases. Therefore, a positive judgment is continuously made in s4, that is, no matter how much time has passed, the measured air pressure Pm is less than the target air pressure Po. Therefore, air replenishment in s5 is repeated until a negative judgment is made in s2, that is, the measured vehicle height Hm reaches the target vehicle height Ho. Then, air replenishment is performed to make the measured vehicle height Hm become the target vehicle height Ho.

[0059] On the other hand, under the compressed vehicle height state Sc, due to the air replenishment in s5, while the air pressure P increases, the vehicle height H hardly increases. Therefore, a positive judgment is continuously made in s2, that is, no matter how much time has passed, the measured vehicle height Hm is less than the target vehicle height Ho. Therefore, air replenishment in s5 is repeated until a negative judgment is made in s4, that is, the measured air pressure Pm reaches the target air pressure Po. Thus, air replenishment is performed to make the measured air pressure Pm become the target air pressure Po.

[0060] Based on this example, an attempt was made to supplement air to bring the measured vehicle height Hm to the target vehicle height Ho. Specifically, if the measured vehicle height Hm does not meet the target vehicle height Ho within the time required for the measured air pressure Pm to become the target air pressure Po (i.e., the "specified period"), air supplementation is performed to bring the measured air pressure Pm to the target air pressure Po.

[0061] Next, refer to Figure 3 Another example of the air replenishment control process will be described. S1 and S2 are the same as in the previous example. If a positive determination is made in S2, that is, if the measured vehicle height Hm does not reach the target vehicle height Ho, the process proceeds to S2a. In S2a, a predetermined amount of air is replenished to the air suspension 125.

[0062] In the next step, s2b, the air control unit 40 determines whether a predetermined "specified period" has elapsed since the start of air replenishment control. If a negative determination is made, the process returns to s1. On the other hand, if a positive determination is made, the process proceeds to s3. S3 to s5 are the same as in the previous example. After s5, the process returns to s3.

[0063] In summary, based on this other example, an attempt was made to supplement air to bring the measured vehicle height Hm to the target vehicle height Ho. Specifically, if the measured vehicle height Hm does not meet the target vehicle height Ho after a predetermined "specified period," air supplementation is performed to bring the measured air pressure Pm to the target air pressure Po.

[0064] Next, refer to Figure 4An example of transporting vehicle 120 under natural vehicle height Sn will be explained.

[0065] First, at the designated first timing Ta1 under normal mode Mn, the vehicle is switched on. Even so, normal mode Mn is maintained. Then, at the second timing Ta2, the vehicle is switched from normal mode Mn to transport mode Mt. As a result, the vehicle height Hm is also increased. After this second timing Ta2, the vehicle 120 is moved to the desired position within the transport vehicle.

[0066] At the third time point Ta3, the vehicle is OFF. Even so, the transport mode Mt is maintained. At the fourth time point Ta4, the wheels 126 of vehicle 120 are secured to the floor of the transport vehicle by means of the tie-down 181. Thus, while maintaining the natural vehicle height Sn, vehicle 120 is secured to the transport vehicle.

[0067] After the fourth timing point Ta4, air is gradually expelled from the air suspension 125, thereby causing the measured vehicle height Hm to gradually decrease. At the subsequent fifth timing point Ta5, the air control unit 40 performs air replenishment control. As a result, the measured vehicle height Hm rises to the target vehicle height Ho. This process is then repeated multiple times from the fourth timing point Ta4 up to the fifth timing point Ta5.

[0068] At the sixth timing point Ta6, vehicle 120 is released from its restraints. At the seventh timing point Ta7, vehicle ON operation is performed. Even so, transport mode Mt is maintained. Then, vehicle 120 is moved to the desired location outside the transport vehicle. At the eighth timing point Ta8, transport mode Mt is switched to normal mode Mn. As a result, the vehicle height Hm is measured to decrease. At the ninth timing point Ta9, vehicle OFF operation is performed. Even so, normal mode Mn is maintained.

[0069] Next, refer to Figure 5 An example of transporting vehicle 120 under the compression state Sc at vehicle height will be explained.

[0070] From the first time point Tb1 to the third time point Tb3, the situation is the same as in the case described above where the vehicle 120 is transported in its natural vehicle height state Sn. At the subsequent fourth time point Tb4, the body 121 of the vehicle 120 is secured to the floor of the transport vehicle by means of the lashing device 182. As a result, the vehicle 120 enters a compressed vehicle height state Sc. Consequently, the vehicle height Hm is measured to decrease, and the air pressure Pm is measured to increase.

[0071] After the fourth timing point Tb4, air is gradually expelled from the air suspension 125, causing the air pressure P to gradually decrease. At the subsequent fifth timing point Tb5, the air control unit 40 performs air replenishment control. As a result, the measured air pressure Pm rises to the target air pressure Po. This process is then repeated multiple times from the fourth timing point Tb4 to the fifth timing point Tb5.

[0072] At the sixth time point Tb6, the restraints on vehicle 120 are released. Vehicle 120 then returns to its natural vehicle height state Sn. As a result, the vehicle height Hm is measured to increase, and the air pressure Pm is measured to decrease. From the seventh time point Tb7 to the ninth time point Tb9, the process is the same as the aforementioned case of transporting vehicle 120 at its natural vehicle height state Sn.

[0073] The following is a summary of the structure and effects of this embodiment.

[0074] exist Figure 1 In the air replenishment control of the air control unit 40 shown, an attempt is made to replenish air so that the measured vehicle height Hm becomes the target vehicle height Ho. Therefore, in Figure 4 As shown in the natural vehicle height state Sn, the vehicle height H can be automatically restored to the target vehicle height Ho by means of air replenishment control at a specified time.

[0075] On the other hand, Figure 5 As shown in the vehicle height compression state Sc, even when air is supplied to the air suspension 125, only the air pressure P increases, while the vehicle height H hardly increases. Therefore, the measured vehicle height Hm does not meet the target vehicle height Ho after a specified time. In this case, air is supplied to bring the measured air pressure Pm to the target air pressure Po. Thus, in the vehicle height compression state Sc, the air pressure can be automatically restored to the target air pressure Po through controlled air supply at a predetermined time. This prevents the vehicle body 121 from becoming loose.

[0076] In summary, according to this embodiment, in Figure 4 The natural vehicle height state Sn shown is Figure 5 In any of the vehicle height compression states Sc shown, air can be automatically and smoothly replenished to the air suspension 125 at a specified time.

[0077] Figure 1The air control unit 40 shown is configured to switch between a normal mode Mn and a transport mode Mt. In the normal mode, air replenishment control is not performed at predetermined times. Therefore, as in this embodiment, by setting the transport mode Mt when the transport vehicle 120 is in operation and the normal mode Mn otherwise, air replenishment control can be performed only at predetermined times when the transport vehicle 120 is in operation. Thus, accidental air replenishment control during operation can be avoided.

[0078] Furthermore, by switching to transport mode Mt when the transport vehicle reaches speed 120 or before, the operator can avoid the need for manual air replenishment. Additionally, it can prevent human error such as the operator forgetting to replenish the air.

[0079] In transport mode Mt, after air replenishment control is completed, air replenishment control is triggered again after a predetermined replenishment interval. Therefore, air replenishment control can be performed efficiently at each specified time.

[0080] The air control unit 40 continues in transport mode Mt regardless of vehicle ON or OFF operations. Therefore, even when vehicle ON or OFF operations are performed to load or unload vehicle 120 relative to the transport means, there is no need to worry about transport mode Mt being deactivated. On the other hand, it switches to normal mode Mn based on the operation of selecting normal mode Mn. Therefore, after unloading vehicle 120 from the transport means, it can quickly revert to normal mode Mn.

[0081] When using a ramp to load or unload vehicle 120 relative to a transportation means, the lower surface of the vehicle body 121 may easily come into contact with the floor surface at the start and end points of the ramp. Therefore, in this embodiment, a target vehicle height Ho is set to be higher than the vehicle height Hn in the conventional mode Mn. Thus, in the transportation mode Mt, the risk of the lower surface of the vehicle body 121 contacting the floor surface can be reduced.

[0082] [Other Implementation Methods]

[0083] The embodiments shown above can be modified, for example, as follows. Figure 1 If the lower surface of the vehicle body 121 shown is high enough, the target vehicle height Ho in transport mode Mt can be set to the vehicle height Hn in normal mode Mn. Alternatively, if there are no particular problems even when air replenishment control is performed during driving, the switching between transport mode Mt and normal mode Mn can be canceled, and transport mode Mt as described in the first embodiment can always be maintained.

[0084] Figure Labels

[0085] 30 vehicle height sensors

[0086] 50 air pressure sensor

[0087] 40 Air Control Department

[0088] 100 vehicle height adjustment device

[0089] 120 vehicles

[0090] 125 air suspension

[0091] H-car height

[0092] Hm measures vehicle height

[0093] Hn vehicle height in normal mode

[0094] Ho target car height

[0095] P air pressure

[0096] Pm measures air pressure

[0097] Po target air pressure

Claims

1. A vehicle height adjustment device, mounted on a vehicle equipped with air suspension, and comprising: The vehicle height sensor obtains the measured value of the vehicle height, which is the vehicle height measurement. An air pressure sensor acquires the measured value of the air pressure within the aforementioned air suspension, which is equivalent to measuring the air pressure; and, The air control department performs prescribed air replenishment control at designated times; and... In the aforementioned air replenishment control, an attempt is made to replenish the air suspension to make the aforementioned measured vehicle height become the specified target vehicle height. If the aforementioned measured vehicle height does not meet the aforementioned target vehicle height for a specified period of time, the aforementioned air replenishment is performed to make the aforementioned measured air pressure become the specified target air pressure.

2. The vehicle height adjustment device according to claim 1, wherein, The aforementioned air control unit is configured to switch between a transport mode in which the aforementioned air replenishment control is performed at the aforementioned specified time, and a conventional mode in which the aforementioned air replenishment control is not performed at the aforementioned specified time.

3. The vehicle height adjustment device according to claim 2, wherein, There are multiple instances where the aforementioned provisions exist. In the aforementioned transportation mode, after the aforementioned air replenishment control is completed, the aforementioned air replenishment control is performed again with the specified replenishment interval as a trigger, thereby performing the aforementioned air replenishment control at each of the aforementioned specified times.

4. The vehicle height adjustment device according to claim 2 or 3, wherein, The aforementioned air control unit, The operation of selecting the aforementioned transportation mode will switch to the aforementioned transportation mode. Under the aforementioned transportation mode, regardless of whether the operation that enables the vehicle to move (vehicle ON operation) or the operation that disables the vehicle to move (vehicle OFF operation) is performed, the transportation mode continues. Switching to the aforementioned normal mode based on the operation of selecting the aforementioned normal mode.

5. The vehicle height adjustment device according to claim 2 or 3, wherein, In the aforementioned transportation mode, the target vehicle height is set to a height that is higher than the vehicle height in the aforementioned conventional mode.

Images