Level control system and level control method for a vehicle

Abstract

The invention relates to a level control system and a level control method for a vehicle, by which a vehicle body is cushioned relative to a vehicle axle, comprising a compressor, an air spring and a first compressed air reservoir for a first pressure level, wherein the suction side of the compressor is connected to the atmosphere via an atmosphere line, wherein the air spring and the first compressed air reservoir are connected to the compression side of the compressor via a supply line, further comprising a first pressure line, by which the first compressed air reservoir can be connected to the suction side of the compressor via a first valve. A second compressed air reservoir is provided for a second pressure level, which is higher than the first pressure level, wherein the second compressed air reservoir can be connected to the compression side of the compressor via the supply line, wherein the second compressed air reservoir can be connected to the reservoir line of the first compressed air reservoir via a second connection valve by means of a second connection line, so that the level control system can be operated in cascade.

Description

Technical Field

[0001] The present invention relates to a leveling control system for a vehicle, which cushions the vehicle body relative to at least one axle, comprising a compressor, at least one air spring, at least one first compressed air reservoir for a first pressure level, and at least one first pressure line.

[0002] The present invention also relates to a method for leveling a vehicle, wherein the vehicle body is buffered relative to at least one axle. Background Technology

[0003] In the prior art, horizontal control systems that use air from a pressure storage device for height control are known.

[0004] For example, a level control device of this type is described in DE 10 2008 034 240 B4. This level control device includes a two-stage compressor, also referred to hereinafter as a compressor, having a first compression stage and a second compression stage. The pressure medium is pre-compressed in the first compression stage and introduced through connecting lines to the second compression stage, where it is further compressed. The compressed pressure medium can be introduced into a pressure medium storage container. The pressure medium stored in the pressure medium storage container can be delivered through pressure medium lines and switching valves to the suction chamber of the second compression stage for further compression; this can be called a "boost function" and improves energy efficiency because the energy from the residual compressed air in the pressure medium storage container can be used to generate compressed air. The pressure medium can continue to be delivered to the air springs, thereby lifting the vehicle. Multi-stage compressors are used in level control devices to achieve high pressure levels in the air springs and pressure medium storage containers through multi-stage compression of the compressor.

[0005] DE 10 2012 006 382 A1 also discloses another pressure medium supply device for operating pneumatic equipment, wherein the pressure medium supply device includes a two-stage compressor. Therefore, pre-compressed compressed air from the air spring and compressed air reservoir can be simultaneously introduced not only into the intake chamber of the second compressor stage but also into the compression chamber of the first compressor stage, allowing the compressor to be pre-charged with compressed air from the air spring and compressed air reservoir. In DE10 2012 006 382 A1, the required pressure level is also achieved through a multi-stage compressor.

[0006] Also of the same type is DE 10 2012 010390A1, which proposes a boosting function by guiding residual compressed air from the compressed air reservoir back to the intake side of the first-stage compressor.

[0007] For known horizontal control systems, the problem is that the pressurization function in the pneumatic system must be frequently activated to achieve the required pressure level, and an additional compressed air energy storage device cannot be integrated, especially for repetitive compressed air demands, to reduce the frequency and duration of compressor activation. Therefore, a trade-off between high volumetric flow rate and high pressure level must be considered when arranging multi-stage compressors, thus preventing the achievement of optimal efficiency and high energy efficiency.

[0008] Furthermore, under the previously known conditions of frequent operation of compressed air systems, operating noise increases to the point of being excessive. Summary of the Invention

[0009] Based on the above-mentioned prior art, the purpose of this invention is to provide a level control system for a vehicle and a method for level control of a vehicle, which can achieve better efficiency and higher energy efficiency as well as a significant increase in speed, wherein the compressor system of the level control system can be compactly integrated into the vehicle with a small spatial construction size and the operating noise of the compressor system is reduced.

[0010] This objective is achieved by a horizontal control system having the features of claim 1 and a method having the features of claim 10. Advantageous modifications of the invention are the subject of the dependent claims.

[0011] This invention relates to a leveling control system for a vehicle, which cushions the vehicle body relative to at least one axle, comprising:

[0012] - Compressor (compressor), wherein the suction side of the compressor is connected to the atmosphere via an atmospheric pipe.

[0013] - At least one air spring and at least one first compressed air reservoir for a first pressure level, wherein the at least one air spring and the first compressed air reservoir are connected to the compression side of the compressor via a supply line.

[0014] - At least one first pressure line, through which the first compressed air reservoir can be connected to the suction side of the compressor via at least one first valve.

[0015] According to the present invention, at least one second compressed air reservoir is provided for a second pressure level, the second pressure level being higher than the first pressure level of the first compressed air reservoir, wherein the second compressed air reservoir can be connected to the compression side of the compressor via the supply line, and wherein the second compressed air reservoir can be connected to the reservoir line of the first compressed air reservoir via a second connecting line through at least one second connecting valve, thereby enabling the level control system to operate in cascade.

[0016] Therefore, a horizontal control system is proposed, comprising at least one two-stage compressed air storage system, including a first compressed air reservoir for a first pressure level and a second compressed air reservoir for a second pressure level. The second pressure level is higher than the first pressure level. This achieves the separate storage of low-pressure air and high-pressure air in the horizontal control system. The compressor's suction chamber can be connected to the atmosphere via a check valve that opens in the compressor's suction direction.

[0017] Two compressed air reservoirs can be connected to the compression side of the compressor via supply lines and separate reservoir lines, with reservoir valves arranged in each reservoir line. The second compressed air reservoir can advantageously be connected to the reservoir line of the first compressed air reservoir via at least one second connecting valve through a second connecting line. This allows the first compressed air reservoir to be filled to a first pressure level by air drawn from the atmosphere and compressed by the compressor via the supply line and its reservoir line when the reservoir valve of the first compressed air reservoir is open. Furthermore, when the second connecting valve in the second connecting line is open, the resulting compressed air is supplied to the second compressed air reservoir via the second connecting line, and the second compressed air reservoir is thereby filled to a second pressure level.

[0018] The feature that the first compressed air reservoir can be connected to the suction side of the compressor via at least one first valve and a first pressure line allows the compressor to be pre-charged with compressed air from the first compressed air reservoir to a pressure level still contained within the first compressed air reservoir. As a result, the compressor starts at the initial pressure provided by the pre-charge for compression, and the pressure level of the level control system is further increased by the compressor, thus providing a pressurization function. The further compressed air is then introduced into the second compressed air reservoir via a supply line with the storage valve of the second compressed air reservoir open, wherein the storage valve of the first compressed air reservoir and the second connecting valve are closed. This advantageously ensures that the second compressed air reservoir can be filled to a second pressure level via the pressurization function.

[0019] Advantageously, the compressor is precharged by a pre-filled compressed air reservoir so that the compressed air can be compressed again to the next higher pressure level, allowing the level control system to operate in cascade. Furthermore, it advantageously enables the air spring to be filled in a short time, thus allowing the air spring to be rapidly pressurized to the desired pressure level.

[0020] Advantageously, the first compressed air reservoir is used to achieve short-term pre-charging of the compressor. This increases the volumetric flow rate and maximum pressure when lifting the vehicle. This advantageously enables the so-called power flow function or boosting function.

[0021] Furthermore, it is advantageous to realize, by means of a compressed air reservoir, an additional backflow function can be realized in the level control system (if necessary, with the addition of additional piping and valves), so that pre-compressed compressed air can be introduced from the air spring via the compressor into at least one compressed air reservoir, preferably into a second high-pressure reservoir.

[0022] Furthermore, it is advantageous that, depending on the storage size of the compressed air reservoir, it can be a closed-loop horizontal control system or a closed air supply, so that the pressure from the air springs is not released into the environment when not in use, but is instead stored back in a compressed air reservoir. In other words, the compressed air from the air springs is directed to the compressed air reservoir and stored there.

[0023] Another advantage is that the pressure level of the level control system can be raised to a level higher than the pressure that the compressor can apply from atmospheric pressure. Advantageously, filling the pressure reservoir to maximum pressure is done in multiple steps, thereby reducing the pressure level requirements on the compressor. Thus, the pressure stages in this level control system are not provided directly within the compressor, but rather through at least two, and often more, arranged compressed air reservoirs, thus eliminating the need for and necessity of multi-stage compressors. This improves efficiency and energy efficiency, and significantly increases the lifting speed. Furthermore, it is advantageous to achieve compact integration of the compressor into the vehicle with a smaller spatial footprint, and due to the fewer compressor stages, compressor operating noise can be reduced.

[0024] It may also advantageously include a pressure sensor for detecting the air pressure in the compressed air reservoir and the air spring and for generating a pressure signal in response thereto, wherein the pressure sensor is arranged in the supply line. The pressurization function can be activated based on the pressure signal by feeding back the remaining compressed air in the first compressed air reservoir.

[0025] Furthermore, at least one decoupling valve is advantageously arranged in the supply line so that, during pressure measurement, the supply line, which has a connected compressed air reservoir and an air spring, can be decoupled from the compressed air flow escaping from the dryer.

[0026] Advantageously, at least one additional air filter is provided in the atmospheric duct so that air from the atmosphere can be filtered before entering the compressor.

[0027] In an advantageous modification of the horizontal control system, at least one third compressed air reservoir for a third pressure level higher than the second pressure level of the second compressed air reservoir can be arranged. The third compressed air reservoir is connected to the compression side of the compressor via a supply line, the second compressed air reservoir is connected to the suction side of the compressor via a second pressure line through at least one second valve, and the third compressed air reservoir is connected to the reservoir line of the second compressed air reservoir via at least one third connecting valve through a third connecting line. Therefore, in this embodiment, a three-stage compressed air storage system is implemented, comprising a first compressed air reservoir for a first pressure level, a second compressed air reservoir for a second pressure level, and a third compressed air reservoir for a third pressure level, wherein the first pressure level is lower than the second pressure level, and the second pressure level is lower than the third pressure level. Thus, the compressed air storage system is provided for storing low-pressure air, medium-pressure air, and high-pressure air, wherein boosting functions from the low-pressure and medium-pressure levels are possible. This allows for a three-stage cascade with two boosting stages.

[0028] This allows air drawn from the atmosphere and compressed by the compressor to be introduced into the first, second, and third compressed air reservoirs via supply lines when the storage valve of the first compressed air reservoir is open and the second and third connection valves are open.

[0029] The second compressed air reservoir is connected to the suction side of the compressor via a second pressure line and a second valve. This allows the compressor to be pre-charged not only with the low-pressure stage pressure from the first compressed air reservoir but also with the medium-pressure stage pressure from the second compressed air reservoir. Therefore, a pressurization function can be achieved by returning compressed air from both the first and second compressed air reservoirs. The pre-compressed compressed air can be further compressed by the compressor and delivered to the third compressed air reservoir via a supply line and an open storage valve. Furthermore, the first and second compressed air reservoirs can advantageously be used solely for pre-charging the compressor. Advantageously, in this embodiment, an additional return function can be achieved by adding more lines and valves, allowing pre-compressed compressed air from the air spring to be directly or, as needed, via the compressor to at least one compressed air reservoir. Thus, a closed system can be achieved where air can be transferred from the compressed air reservoir to the air spring and then back.

[0030] In another advantageous modification, the compressor can be designed as a two-stage compressor, comprising at least a first compression stage having a first intake chamber and a first compression chamber, and a second compression stage having a second intake chamber and a second compression chamber. The first intake chamber is connected to the atmosphere via an atmospheric line, the first compression chamber is connected to the second intake chamber, and an air spring, a first compressed air reservoir, a second compressed air reservoir, and preferably a third compressed air reservoir are connected to the second compression chamber of the second compression stage via a supply line. This provides a two-stage compressor. Advantageously, the first and second compression stages can be used together to fill the compressed air reservoirs and / or the air springs. Furthermore, it is advantageous that only the second compression stage is used to rapidly fill the air springs to high pressure using compressed air from the second and / or third compressed air reservoirs. Also advantageously, by compressing pre-compressed compressed air from the first and / or second compressed air reservoirs, the air springs can be filled in a short time. Therefore, the air springs can be rapidly pressurized to the desired pressure level.

[0031] Based on previous embodiments, in a further advantageous modification, the first compressed air reservoir may be connected via a first valve to the first intake chamber of the first compression stage and / or to the second intake chamber of the second compression stage, wherein the first intake chamber is connected to the atmosphere via an atmospheric conduit. Therefore, the compressor can be pre-charged with pressure from the first compressed air reservoir via the first and / or second compression stages. In this regard, when the first valve is open, compressed air from the first compressed air reservoir can be supplied to the second intake chamber of the second compression stage, thereby pre-charging the second compression stage with compressed air from the first compressed air reservoir and further using it to fill the second and / or third compressed air reservoirs and for lifting the vehicle. This can increase the lifting speed. Alternatively, the first compression stage can be used for pre-charging. Furthermore, both compression stages can be pre-charged with pre-compressed compressed air from the first compressed air reservoir, wherein compressed air is supplied to both the first and second intake chambers.

[0032] As an alternative to the previous embodiment, in a further advantageous modification, the second compressed air reservoir can be connected via a second pressure line and a second valve to the first intake chamber of the first compression stage and / or the second intake chamber of the second compression stage. Therefore, the compressor can be pre-charged by the first and / or second compression stages at pressure from the second compressed air reservoir, such that compressed air from the second compressed air reservoir is delivered to the first and / or second intake chambers via the second pressure line with the second valve open.

[0033] In principle, the present invention can be implemented using a cylinder compressor with a oscillating piston. However, a rotary compressor with a rotating piston rather than an oscillating piston is preferred. These result in smoother operation and lower noise levels. Furthermore, rotary compressors have similar aerodynamic characteristics to cylinder compressors, but at lower pressure levels, thus increasing volumetric flow rates. Therefore, rotary compressors are suitable for combination with cascade connections according to the invention to achieve even higher pressure levels and higher volumetric flow rates. In a further advantageous modification in this context, the compressor can be designed as a single-stage or two-stage compressor, particularly the first and / or second compression stages, which are designed as rotary compressors, especially scroll compressors. Scroll compressors can thus generate air pressure effortlessly, with reduced noise and vibration. A scroll compressor comprises two meshing scrolls whose counter-movement compresses the gas. Advantageously, scroll compressors are particularly low in maintenance costs and quiet due to their valveless design. Even under extreme environmental conditions, such as rain, dust, ice deposits, and low temperatures, scroll compressors can be used due to their stable characteristics.

[0034] In a further advantageous modification, the second and / or third connecting valves can be designed as check valves, thereby blocking compressed air in the direction from the second and / or third compressed air reservoir to the first and / or second compressed air reservoir. This advantageously allows the pressurization function to be implemented through the compressed air reservoir used for the lower pressure level, without pressure escaping from the compressed air reservoir used for the higher pressure level.

[0035] In a further advantageous modification, the first and second valves can be designed as two-position, two-way valves. This allows the first and second valves to be switched to different circuit positions. The first and second valves can be electrically controlled, meaning they can be connected to the electrical terminals of a control device. Advantageously, the first and second valves are electrically operated and do not require complex mechanical connections or pneumatic pilot controls for actuating them. Using electrically operated valves allows for very simple installation at a minimal cost.

[0036] As an alternative, the first and second valves can also be pneumatically controlled. Compared to electrically operated valves, a connection for compressed air is provided instead of an electrical connection, allowing the valve to be switched by controlling the compressed air. Using pneumatic valves allows for minimal cost and eliminates the need for additional, potentially faulty electrical components.

[0037] In another advantageous improvement, the first compressed air reservoir may have a larger storage volume than the second compressed air reservoir, and preferably, the second compressed air reservoir may have a larger storage volume than the third compressed air reservoir. This allows sufficient volume of compressed air to be obtained from the first and / or second compressed air reservoirs and prepared for recompression. Consequently, sufficient compressed air with high pressure can be generated for the second and / or third compressed air reservoirs.

[0038] In a parallel aspect, the present invention relates to a method for leveling a vehicle using a leveling control system as described above, by which the vehicle body is buffered relative to at least one axle.

[0039] According to the present invention, compressed air from a first compressed air reservoir is supplied to the suction side of a compressor via a first pressure line and a first valve, the pressure of the compressed air is increased by the compressor, and the compressed air is supplied to a second and / or a third compressed air reservoir via a supply line and preferably via at least one storage valve.

[0040] Therefore, a method for level control of a vehicle is proposed, wherein the compressor is pre-charged with pressure from a first compressed air reservoir. The pressure of the compressed air from the first compressed air reservoir can be increased by recompression. The further compressed air is directed via supply lines to a second and / or a third compressed air reservoir. In this way, the compressed air reservoirs can be filled to their maximum pressure level. This method advantageously achieves the ability to bring the pressure level of the level control system to a high-pressure level in multiple stages without the need for compressors operating at higher pressures and drive motors with higher power.

[0041] In an advantageous modification, the first compressed air reservoir can be filled to at least a first pressure level by drawing in air that enters from the atmosphere and is compressed by the compressor when the reservoir valve is open. Advantageously, the pressure within the first compressed air reservoir can be increased directly by the compressed air generated by the compressor.

[0042] In a further advantageous modification, with the second connecting valve closed and the storage valve of the second compressed air reservoir open, the second compressed air reservoir can be filled to at least a second pressure level by drawing in air from the atmosphere or air returned to the intake side from the first compressed air reservoir and compressed by the compressor. The second compressed air reservoir can be filled to its maximum pressure level such that air drawn in from the atmosphere is first compressed by the compressor and then directly supplied to the second compressed air reservoir. Furthermore, compressed air from the first compressed air reservoir can first be returned to the compressor and further compressed there. The recompressed compressed air can then be supplied to the second compressed air reservoir, thereby filling the second compressed air reservoir to its maximum pressure level.

[0043] In a further advantageous modification, with the third connecting valve closed and the storage valve of the third compressed air reservoir open, the third compressed air reservoir can be filled to at least a third pressure level by drawing in air from the atmosphere or air guided back to the intake side from the first and / or second compressed air reservoirs and compressed by the compressor. This provides several possibilities for filling the third compressed air reservoir. The third compressed air reservoir can be filled directly with air drawn in from the atmosphere and compressed by the compressor. Alternatively, the third compressed air reservoir can be filled with compressed air guided from the first and / or second compressed air reservoirs to the compressor and further compressed there to a higher pressure level.

[0044] In another advantageous modification, the vehicle body can be lifted via air springs, allowing compressed air from the second and / or third compressed air reservoirs to be directed into the air springs. Thus, the vehicle can be lifted via the second compressed air reservoir in a two-stage compressed air reservoir system and / or via the third compressed air reservoir in a three-stage compressed air reservoir system. This advantageously allows the air springs to be filled directly through the compressed air reservoirs without having to start the compressor.

[0045] In another advantageous improvement, compressed air from the first or second compressed air reservoir, supplied via the first and / or second pressure lines to the intake side of the compressor and further compressed by the compressor, can be directed to the air spring for lifting the vehicle body. This allows the vehicle to be lifted via a booster function, increasing the lifting speed.

[0046] In a further advantageous improvement, compressed air from the compressor's compression side can be directly supplied to the air springs via a supply line to lift the vehicle body. In other words, the air springs can be directly filled by the compressor. Attached Figure Description

[0047] Other advantages of the invention are illustrated in the accompanying drawings and their corresponding descriptions.

[0048] Embodiments of the invention are illustrated in the accompanying drawings. The drawings, description, and claims contain numerous combinations of features. Those skilled in the art can readily contemplate these features individually and combine them into other meaningful combinations. In the drawings:

[0049] Figure 1 This is a schematic diagram of a horizontal control system based on existing technology;

[0050] Figure 2 It is a schematic diagram of a horizontal control system with a first compressed air reservoir, based on the prior art;

[0051] Figure 3 This is a schematic diagram of a first embodiment of the horizontal control system according to the present invention;

[0052] Figure 4 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0053] Figure 5 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0054] Figure 6 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0055] Figure 7 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0056] Figure 8 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0057] Figure 9 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0058] Figure 10 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0059] Figure 11 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0060] Figure 12 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0061] Figure 13 This is a schematic diagram of another embodiment of the horizontal control system of the present invention;

[0062] Figures 14a-14cThis is a schematic diagram of a first embodiment of a method for level control of a vehicle according to the present invention;

[0063] Figure 15 This is a schematic diagram of another embodiment of the method according to the present invention;

[0064] Figure 16 This is a schematic diagram of another embodiment of the method according to the present invention.

[0065] In the figures, identical or similar parts are identified by the same reference numerals. Detailed Implementation

[0066] Figure 1 The diagram schematically illustrates a leveling control system 10 known in the prior art for vehicles. This leveling control system 10 is designed to operate the vehicle's air springs 18. Each air spring 18 is connected to a supply line 26 via an air spring valve 72, which is designed as a two-position two-way valve 52. The leveling control system 10 has a single-stage compressor 12, which is operated by an electric motor 58 connected to an atmospheric line 16 on the suction side 14 of the compressor 12. The supply line 26, containing a dryer 54, is connected to a compression side 30. An inlet valve 48 is located on the suction side 14, and a switching valve 62 is located on the compression side 30; both valves are designed as check valves 50. A discharge line 74 branches off from the supply line 26 between the compressor 12 and the dryer 54. This discharge line contains a discharge valve 66 designed as a two-position two-way valve 52 and opens downstream of the discharge valve 66 to the atmosphere. A decoupling valve 64, implemented as a two-position two-way valve 52, is arranged in the supply line 26 to decouple the compressed air flow escaping from the dryer 54 when the pressure of the air spring 18 is measured. Furthermore, an air filter 56 with a silencer is provided in the atmospheric line 16 so that air from the atmosphere is filtered before entering the compressor 12. Also included is a pressure sensor 68 for detecting the air pressure in the air spring 18 and generating a pressure signal in response thereto; the pressure sensor 68 is contained in the supply line 26.

[0067] exist Figure 2 The diagram schematically illustrates another leveling control system 10 known in the prior art for vehicles. This leveling control system 10 is essentially the same as that according to... Figure 1 The embodiment is consistent with that of the previous one. However, this embodiment is different from... Figure 1The difference in the illustrated embodiment is that the first compressed air reservoir 20 is connected to the suction side 14 of the compressor 12 via a first pressure line 28 and a first valve 46, which is designed as a two-position two-way valve 52. When the first valve 46 is open, compressed air can be supplied from the first compressed air reservoir 20 to the suction side 14 of the compressor 12, so that the compressed air can be further compressed by the compressor 12. Thus, the compressor 12 can be pre-charged by pressure from the first compressed air reservoir 20. The first compressed air reservoir 20 can also be further connected to the supply line 26 via a reservoir line 34 and a storage valve 70a, which is designed as a two-position two-way valve 52. Thus, when the storage valve 70a is open, the compressed air generated by the compressor 12 can be guided into the first compressed air reservoir 20. In addition, the suction side 14 of the compressor 12 is connected to the atmosphere via an atmospheric line 16 and two inlet valves 48, wherein the inlet valves 48 are designed as check valves 50 that open in the suction direction of the compressor 12.

[0068] exist Figure 3The diagram schematically illustrates a first embodiment of a level control system 10 according to the present invention. A compressor 12 is included in the level control system 10, wherein the suction side 14 of the compressor 12 is connected to the atmosphere via an atmospheric line 16 through two inlet valves 48. It also includes four air springs 18 and a first compressed air reservoir 20 for a first pressure level, wherein the air springs 18 are respectively connected to a supply line 26 via air spring valves 72. The first compressed air reservoir 20 is connected to the supply line 26 via a reservoir line 34 through a reservoir valve 70a, such that when the reservoir valve 70a is open, compressed air can be introduced into the first compressed air reservoir 20 through the supply line 26 and the reservoir line 34. Furthermore, the first compressed air reservoir 20 is connected to the suction side 14 of the compressor 12 via a first pressure line 28 through a first valve 46, so that compressed air from the first compressed air reservoir 20 can be returned to the suction side 14. Thus, a pressurization function can be achieved. The level control system 10 also includes a second compressed air reservoir 22 for a second pressure level higher than the first pressure level of the first compressed air reservoir 20. The second compressed air reservoir 22 is connected to the reservoir line 34 of the first compressed air reservoir 20 via a second connecting valve 32 and a second connecting line 38. Therefore, when the compressed air reservoirs 20 and 22 are filled, compressed air discharged from the compression side 30 of the compressor 12 can be introduced into the first compressed air reservoir 20 via the reservoir line 34 when the reservoir valve 70a is open, and into the second compressed air reservoir 22 via the reservoir line 34 of the first compressed air reservoir 20 and the second connecting line 38 when the second connecting valve 32 is open. Furthermore, the second compressed air reservoir 22 can be connected to the compression side 30 via a reservoir line 34 containing a reservoir valve 70b and a supply line 26. Thus, by means of a pressurization function, compressed air recompressed by the compressor 12 at an increased pressure is introduced into the second compressed air reservoir 22 via the reservoir line 34 through the supply line 26 when the reservoir valve 70b is open, and it can be filled to a second pressure level. Therefore, the level control system 10 can operate in cascade. The reservoir valves 70a, 70b, the first valve 46, and the air spring valve 72 are designed as two-position two-way valves 52. Furthermore, the second connecting valve 32 is designed as a check valve 50. The other structural features of the level control system 10 are essentially the same as... Figure 2 The horizontal control system shown is consistent with that of the system.

[0069] Figure 4 Another embodiment of the horizontal control system 10 according to the present invention is illustrated schematically. This horizontal control system 10 is related to... Figure 3 The structural construction of the embodiments is basically the same. Figure 4 The horizontal control system 10 shown is with Figure 3The difference in the embodiment is that a third compressed air reservoir 24 is provided for a third pressure level, which is higher than the second pressure level of the second compressed air reservoir 22. The third compressed air reservoir 24 can be connected to the compression side 30 of the compressor 12 via a reservoir line 34 and a supply line 26, in which a storage valve 70c, designed as a two-position two-way valve 52, is arranged. Therefore, when the storage valve 70c is open, compressed air from the compression side 30 can be introduced into the third compressed air reservoir 24 via the supply line 26 and the reservoir line 34. For pre-charging the compressor 12, not only is the first compressed air reservoir 20 connected to the suction side 14 of the compressor 12 via a first pressure line 28, but the second compressed air reservoir 22 is also connected to the suction side 14 of the compressor 12 via a second pressure line 42 and a second valve 60, designed as a two-position two-way valve 52. Thus, when the second valve 60 is open, the compressor 12 can be pre-charged by the pressure from the second compressed air reservoir 22. The third compressed air reservoir 24 can also be connected to the reservoir line 34 of the second compressed air reservoir 22 via the third connecting line 40 and the third connecting valve 44, which is designed as a check valve 50. Therefore, compressed air can be supplied to the third compressed air reservoir 24 through the supply line 26 and via the connecting line 40 and the reservoir line 34 until the third pressure level is reached.

[0070] Figure 5 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 is related to... Figure 3 The structural construction of the embodiments is basically the same. However, Figure 5 The horizontal control system 10 shown is with Figure 3The difference in the embodiment is the use of a two-stage compressor 12. This compressor 12 has a first compression stage 12a with a first intake chamber 14a and a first compression chamber 30a, and a second compression stage 12b with a second intake chamber 14b and a second compression chamber 30b. The first intake chamber 14a is connected to the atmosphere via an atmospheric line 16 through an inlet valve 48 configured as a check valve 50. Furthermore, the first compression chamber 30a can also be connected to the second intake chamber 14b via two inlet valves 48 configured as check valves 50. Additionally, an air spring 18, a first compressed air reservoir 20, and a second compressed air reservoir 22 are connected to the second compression chamber 30b of the second compression stage 12b via a supply line 26. Furthermore, the first compressed air reservoir 20 can be connected to the second intake chamber 14b of the second compression stage 12b via a first pressure line 28 through a first valve 46, which is designed as a two-position two-way valve 52, and an inlet valve 48, so that the second compression stage 12b can be pre-charged by pressure from the first compressed air reservoir 20. Furthermore, a check valve 50 is provided upstream of the intake chamber 14a of the first compression stage 12a, which opens in the intake direction of the first compression stage 12a. This check valve is configured as an inlet valve 48, thereby allowing the first compression stage 12a to be connected to the atmosphere.

[0071] Figure 6 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 is related to... Figure 5 The structural construction of the embodiments is basically the same. Figure 6 The horizontal control system 10 shown is with Figure 5 The difference in the embodiment is that the first compressed air reservoir 20 is connected to the first intake chamber 14a of the first compression stage 12a of the compressor 12 via a first pressure line 28 with a built-in first valve 46, wherein the first valve 46 is designed as a two-position two-way valve 52. Thus, compressed air can be returned from the first compressed air reservoir 20 to the first intake chamber 14a. With the second connection valve 32 closed and the reservoir valve 70b open, the second compressed air reservoir 22 can be filled to at least a second pressure level by compressed air further compressed by the first compression stage 12a.

[0072] Figure 7 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 substantially corresponds to the one according to... Figure 5 and Figure 6 The structural construction of the combination of embodiments. Figure 7 The horizontal control system 10 shown is with Figure 6 The difference in the embodiments is that, according to Figure 5A key feature of this embodiment, namely the difference, is that the first compressed air reservoir 20 is connected not only to the first suction chamber 14a of the first compression stage 12a of the compressor 12 via a first pressure line 28 and a first valve 46, but also to the second suction chamber 14b of the second compression stage 12b of the compressor 12 via a second pressure line 42 and a second valve 60. The first and second valves 46 and 60 are designed as two-position two-way valves 52. Thus, pre-charging of the compressor 12 can be performed by pre-charging the first compression stage 12a and the second compression stage 12b using pressure from the first compressed air reservoir 20.

[0073] Figure 8 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 is related to... Figure 4 The structural construction of the embodiments is basically the same. However, Figure 8 The horizontal control system 10 shown is with Figure 4 The difference in the embodiment is the inclusion of a two-stage compressor 12. This compressor 12 has a first compression stage 12a with a first intake chamber 14a and a first compression chamber 30a, and a second compression stage 12b with a second intake chamber 14b and a second compression chamber 30b. The first intake chamber 14a is connected to the atmosphere via an atmospheric line 16 through an inlet valve 48 configured as a check valve 50. To load the compressor 12, a first compressed air reservoir 20 can be connected to the second intake chamber 14b of the second compression stage 12b via a first valve 46 through a first pressure line 28, wherein the first valve 46 is designed as a two-position two-way valve 52. In this embodiment, the second compressed air reservoir 22 can also be connected to the second intake chamber 14b via a second valve 60, which is also designed as a two-position two-way valve 52, through a second pressure line 42, thereby allowing the compressor 12 to be precharged using pressure from both the first and second compressed air reservoirs 20 and 22.

[0074] exist Figure 9 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 is... Figure 8 The structural construction of the embodiments shown is basically the same. However, Figure 9 The horizontal control system 10 shown is with Figure 8 The difference in the embodiment is that the first compressed air reservoir 20 and the second compressed air reservoir 22 are respectively connected to the first suction chamber 14a of the first compression stage 12b of the compressor 12 via the first valve 46 and the second valve 60 through the first pressure line 28 and the second pressure line 42. The first and second valves 46 and 60 are designed as two-position two-way valves 52. Thus, the compressor 12 can be pre-charged not only with compressed air from the first compressed air reservoir 20 but also with compressed air from the second compressed air reservoir 22.

[0075] exist Figure 10 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 is... Figure 9 The structural construction of the embodiments shown is basically the same. However, Figure 10 The horizontal control system 10 shown is with Figure 9 The difference in the illustrated embodiment is that the second compressed air reservoir 22 can be connected to the second intake chamber 14b of the second compression stage 12b of the compressor 12 via a second valve 60 configured as a two-position two-way valve 52 through a second pressure line 42. Thus, compressed air can be directed from the first compressed air reservoir 20 to the first intake chamber 14a of the first compression stage 12a, and also from the second compressed air reservoir 22 to the second intake chamber 14b. This allows for pre-charging of the compressor 12.

[0076] Figure 11 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 is related to… Figure 10 The structural construction of the embodiments shown is basically the same. However, Figure 11 The horizontal control system 10 shown is with Figure 10 The difference in the embodiment is that the first compressed air reservoir 20 can be connected not only to the first suction chamber 14a of the first compression stage 12a of the compressor 12 via the first valve 46 and the first pressure line 28, but also to the second suction chamber 14b of the second compression stage 12b of the compressor 12 via another first valve 46 and the first pressure line 28. Since compressed air can be directed from the first compressed air reservoir 20 to both the first and second compression stages 12a and 12b, pre-charging of the compressor 12 with pressure from the first compressed air reservoir 20 can be performed not only via the first compression stage 12a but also via the second compression stage 12b. The first valve 46 is designed as a two-position two-way valve 52.

[0077] exist Figure 12 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 is... Figure 9 The structural construction of the embodiments shown is basically the same. However, Figure 12 The horizontal control system 10 shown is with Figure 9The embodiment differs in that the second compressed air reservoir 22 is connected not only to the first suction chamber 14a of the first compression stage 12a of the compressor 12 via the second valve 60 and the second pressure line 42, but also to the second suction chamber 14b of the second compression stage 12b of the compressor 12 via another second valve 60 and the second pressure line 42. The second valve 46 is designed as a two-position two-way valve 52. Compressed air can therefore be supplied from the second compressed air reservoir 22 to the first suction chamber 14a and the second suction chamber 14b, thereby pre-charging the compressor 12 with pressure from the second compressed air reservoir 22, not only via the first compression stage 12a but also via the second compression stage 12b.

[0078] exist Figure 13 Another embodiment of the horizontal control system 10 according to the present invention is shown. This horizontal control system 10 is... Figure 12 The structural construction of the embodiments shown is basically the same. However, Figure 13 The horizontal control system 10 shown is with Figure 12 The difference in the embodiment is that the first compressed air reservoir 20 can be connected not only to the first intake chamber 14a of the first compression stage 12a of the compressor 12 via a first valve 46 and a first pressure line 28, but also to the second intake chamber 14b of the second compression stage 12b of the compressor 12 via another first valve 46 and a first pressure line 28. The first valve 46 is designed as a two-position two-way valve 52. In this embodiment, compressed air from the first compressed air reservoir 20 can be supplied to the first and second intake chambers 14a, 14b. Furthermore, compressed air from the second compressed air reservoir 22 can also be supplied to the first and second intake chambers 14a, 14b. Therefore, it is possible to precharge the compressor 12 not only with pressure from the first compressed air reservoir 20, but also with pressure from the second compressed air reservoir 22, wherein precharging can be performed not only via the first compression stage 12a but also via the second compression stage 12b.

[0079] exist Figures 14a to 16 The diagram illustrates various methods for leveling a vehicle using the level control system described above.

[0080] exist Figures 14a to 14c The diagram schematically illustrates a first embodiment of a method for level control of a vehicle according to the present invention.

[0081] according to Figure 14aAir from the atmosphere is first compressed to a pressure level by a compressor 12 having an intake side 14 and a compression side 30, and then introduced into a first compressed air reservoir 20 via a supply line 26 and a reservoir line 34, and then introduced into a second compressed air reservoir 22 for a second pressure level via a second connection line 38 when the second connection valve 32 is open. The second connection valve 32 is designed as a check valve 50.

[0082] according to Figure 14b Compressed air stored in the first compressed air reservoir 20 is returned to the intake side 14 via the first pressure line 28 when the first valve 46 is open and is further compressed by the compressor 12. The recompressed compressed air is then introduced into the second compressed air reservoir 22 via the supply line 26 and the reservoir line 34 when the second connection valve 32 is closed, and stored there. The second compressed air reservoir 22 can be filled with compressed air up to a second pressure level.

[0083] according to Figure 14c Compressed air stored in the second compressed air reservoir 22 can be guided to four air springs 18 through the reservoir line 34 and the supply line 26. This allows the vehicle body to be lifted. The compressor 12 is designed as a scroll compressor 36.

[0084] exist Figure 15 Another embodiment of the method according to the invention is illustrated schematically. Figure 15 The horizontal control system used for horizontal control is in Figures 14a to 14c The horizontal control system used for horizontal control is consistent with that used for horizontal control. Air from the atmosphere can be compressed by compressor 12 and guided directly from the compression side 30 through supply line 26 into air spring 18, thereby allowing the vehicle body to be lifted.

[0085] exist Figure 16 Another embodiment of the method according to the invention is illustrated schematically. Figure 16 The horizontal control system used for horizontal control is in Figures 14a to 14c The horizontal control system used for level control is consistent with that used for level control. To raise the vehicle body, compressed air from the first compressed air reservoir 20 is delivered to the suction side 14 of the compressor 12 via the first pressure line 28 and further compressed by the compressor 12. The recompressed compressed air is then directed to the air spring 18.

[0086] List of reference numerals

[0087] 10. Horizontal Control System

[0088] 12 Compressors

[0089] 12a First Compression Stage

[0090] 12b Second Compression Stage

[0091] 14. Inhalation side

[0092] 14a First Inhalation Chamber

[0093] 14b Second Inhalation Chamber

[0094] 16 Atmospheric Pipelines

[0095] 18 Air Springs

[0096] 20 First Compressed Air Storage Unit

[0097] 22 Second Compressed Air Storage Unit

[0098] 24 Third Compressed Air Storage Unit

[0099] 26 Supply pipelines

[0100] 28 First pressure pipeline

[0101] 30 Compression side

[0102] 30a First Compression Chamber

[0103] 30b Second Compression Chamber

[0104] 32 Second connecting valve

[0105] 34. Storage piping

[0106] 36 Scroll compressor

[0107] 38 Second connecting pipe

[0108] 40 Third connecting pipe

[0109] 42 Second pressure pipeline

[0110] 44 Third connecting valve

[0111] 46 First Valve

[0112] 48. Inlet valve

[0113] 50 Check Valve

[0114] 52 Two-position two-way valve

[0115] 54 Dryer

[0116] 56 Air Filters

[0117] 58 Electric Motors

[0118] 60 Second valve

[0119] 62 Switching valve

[0120] 64 Decoupling valve

[0121] 66. Discharge valve

[0122] 68 Pressure Sensor

[0123] 70a, b, and c are storage valves used for the first, second, and third compressed air reservoirs.

[0124] 72 Air Spring Valve

[0125] 74. Discharge pipeline.

Claims

1. A leveling control system (10) for a vehicle, which cushions the vehicle body relative to at least one axle, comprising: - Compressor (12), wherein the suction side (14) of the compressor (12) is connected to the atmosphere via an atmospheric duct (16), - At least one air spring (18) and at least one first compressed air reservoir (20) for a first pressure level, wherein the at least one air spring (18) and the first compressed air reservoir (20) are connected to the compression side (30) of the compressor (12) via a supply line (26). - At least one first pressure line (28), through which the first compressed air reservoir (20) can be connected to the suction side (14) of the compressor (12) via at least one first valve (46). The system includes at least one second compressed air reservoir (22) for a second pressure level higher than the first pressure level of the first compressed air reservoir (20). The second compressed air reservoir (22) is connected to the compression side (30) of the compressor (12) via the supply line (26). The system is characterized in that the second compressed air reservoir (22) is connected to the reservoir line (34) of the first compressed air reservoir (20) via a second connecting line (38) through at least one second connecting valve (32), thereby enabling the level control system (10) to operate in cascade. The second connecting valve (32) is designed as a check valve (50), thereby blocking the compressed air in the direction from the second compressed air reservoir (22) to the first compressed air reservoir (20).

2. The horizontal control system (10) according to claim 1, characterized in that, At least one third compressed air reservoir (24) is provided for a third pressure level higher than the second pressure level of the second compressed air reservoir (22), wherein the third compressed air reservoir (24) can be connected to the compression side (30) of the compressor (12) via the supply line (26), wherein the second compressed air reservoir (22) can be connected to the suction side (14) of the compressor (12) via a second pressure line (42) via at least one second valve (60), and the third compressed air reservoir (24) can be connected to the reservoir line (34) of the second compressed air reservoir (22) via a third connection line (40) via at least one third connection valve (44).

3. The horizontal control system (10) according to claim 2, characterized in that, The compressor (12) includes at least a first compression stage (12a) having a first intake chamber (14a) and a first compression chamber (30a) and a second compression stage (12b) having a second intake chamber (14b) and a second compression chamber (30b), wherein the first intake chamber (14a) is connected to the atmosphere via the atmospheric conduit (16), the first compression chamber (30a) is connected to the second intake chamber (14b), and the air spring (18), the first compressed air reservoir (20), the second compressed air reservoir (22), and the third compressed air reservoir (24) are connected to the second compression chamber (30b) of the second compression stage (12b) via the supply conduit (26).

4. The horizontal control system (10) according to claim 3, characterized in that, The first compressed air reservoir (20) can be connected via the first valve (46) to the first intake chamber (14a) of the first compression stage (12a) and / or to the second intake chamber (14b) of the second compression stage (12b), wherein the first intake chamber (14a) is connected to the atmosphere via the atmospheric conduit (16).

5. The horizontal control system according to claim 3, characterized in that, The second compressed air reservoir (22) can be connected to the first intake chamber (14a) of the first compression stage (12a) and / or to the second intake chamber (14b) of the second compression stage (12b) via the second pressure line (42) and the second valve (60).

6. The horizontal control system (10) according to claim 1, characterized in that, The compressor (12) is designed as a scroll compressor (36).

7. The horizontal control system (10) according to claim 2, characterized in that, The third connecting valve (44) is designed as a check valve (50), thereby enabling the compressed air to be blocked in the direction from the third compressed air reservoir (24) to the second compressed air reservoir (22).

8. The horizontal control system (10) according to claim 2, characterized in that, The first valve (46) and the second valve (60) are designed as two-position two-way valves (52).

9. The horizontal control system (10) according to claim 2, characterized in that, The first compressed air reservoir (20) has a larger storage volume than the second compressed air reservoir (22), and the second compressed air reservoir (22) has a larger storage volume than the third compressed air reservoir (24).

10. A method for leveling a vehicle, wherein the vehicle body is buffered relative to at least one axle by utilizing the leveling control system (10) according to claim 2, characterized in that, Compressed air is supplied from the first compressed air reservoir (20) to the suction side (14) of the compressor (12) via the first pressure line (28) and the first valve (46). The compressor (12) increases the pressure of the compressed air, and the compressed air is supplied to the second and / or third compressed air reservoirs (22, 24) via the supply line (26) and at least one reservoir valve (70b, 70c).

11. The method according to claim 10, characterized in that, With the storage valve (70a) of the first compressed air reservoir (20) open, the first compressed air reservoir (20) is filled to at least a first pressure level by drawing in air that enters from the atmosphere and is compressed by the compressor (12).

12. The method according to claim 10, characterized in that, With the second connection valve (32) closed and the storage valve (70b) of the second compressed air reservoir (22) open, the second compressed air reservoir (22) is filled to at least a second pressure level by drawing in air that enters from the atmosphere or is guided back from the first compressed air reservoir (20) to the intake side (14, 14a, 14b) and is compressed by the compressor (12).

13. The method according to claim 10, characterized in that, With the third connection valve (44) closed and the storage valve (70c) of the third compressed air reservoir (24) open, the third compressed air reservoir (24) is filled to at least a third pressure level by drawing in air that enters from the atmosphere or is guided back to the intake side (14, 14a, 14b) from the first and / or second compressed air reservoirs (20, 22) and is compressed by the compressor (12).

14. The method according to claim 10, characterized in that, The vehicle body is lifted by an air spring (18) so that compressed air from the second and / or third compressed air reservoirs (22, 24) is introduced into the air spring (18).

15. The method according to claim 10, characterized in that, In order to lift the vehicle body, compressed air from the first or second compressed air reservoir (20, 22), which is supplied to the suction side (14, 14a, 14b) of the compressor (12) via the first pressure line (28) and / or the second pressure line (42) and further compressed by the compressor (12), is introduced into the air spring (18).

16. The method according to claim 10, characterized in that, To lift the vehicle body, compressed air is delivered directly from the compression side (30) of the compressor (12) to the air spring (18) via the supply line (26).

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