Pneumatic system and compressed air supply system with bypass line and switching and control actuator system in the ventilating path, and method

Abstract

The invention relates to a pneumatic system (10), comprising a compressor (101), a pneumatic system (200) with at least one compressed air consumer (220), and a compressed air supply system (100) for supplying the pneumatic system (200), with a pneumatic main line (112) between a compressed air connector (1) and a compressed air supply connector (2) with an air dryer (102) and a ventilating path (103). The invention proposes a pneumatic arrangement (130) which is arranged in the ventilating path (103) and has a bypass line (132) with a bypass diameter (Dmin) and a switching and control actuator system (134), wherein the bypass line (132) of a line portion (113.1) of the ventilating path (103) with a ventilating diameter (Dmax) has an actuator element (135) arranged in the line portion (113.1) for selectively opening or shutting off the line portion (113.1). The invention also relates to a compressed air supply system (100), to a vehicle (1000) and to a method (2000) for operating a pneumatic system (10).

Description

[0001] Pneumatic system and compressed air supply system with bypass line and switching and reqeaktorik in the venting path and process

[0002] The present invention relates to a pneumatic system for a vehicle, in particular a passenger car, comprising a compressor for providing compressed air at a supply pressure, a pneumatic system, in particular an air suspension system, with at least one compressed air consumer, a reservoir connected via a storage line, and a compressed air supply system for supplying the pneumatic system with compressed air at a gallery pressure. The compressed air supply system comprises a compressed air connection to the compressor, a compressed air supply connection to the pneumatic system, a pneumatic main line between the compressed air connection and the compressed air supply connection with an air dryer, and a vent path with a vent connection to the environment and a vent line leading from the pneumatic main line to the vent connection.

[0003] The invention also relates to a compressed air supply system for a corresponding pneumatic system, a vehicle with such a pneumatic system and a method for operating such a pneumatic system.

[0004] A compressed air supply system is used in all types of vehicles, in particular to supply a pneumatic system with compressed air, such as a vehicle's air suspension system. The compressed air supply system, together with a compressor and the pneumatic system, forms a pneumatic system. Air suspension systems can also include level control devices with which the distance between the vehicle axle and the vehicle body can be adjusted. An air suspension system of a pneumatic system mentioned above comprises, as compressed air consumers, a number of air bellows pneumatically connected to a common line (gallery), which can raise the vehicle body as their filling increases and lower it accordingly as their filling decreases. With increasing distance between the vehicle axle and the vehicle body orWith increased ground clearance, the spring travel becomes longer and even larger unevenness in the road can be overcome without coming into contact with the vehicle body. Such systems are increasingly being used in off-road vehicles and sport utility vehicles (SUVs). Especially in SUVs with very powerful engines, it is desirable to provide the vehicle with comparatively low ground clearance for high speeds on the road on the one hand, and comparatively high ground clearance for off-road use on the other. It is also desirable to implement changes in ground clearance as quickly as possible, which increases the demands on a compressed air supply system in terms of speed, flexibility and reliability. Rapid lowering of the SUV requires rapid venting of the pneumatic system and in particular the air bellows of the air suspension system to the atmosphere via the vent path.

[0005] To ensure long-term operation of the compressed air supply system, a pneumatic main line of the compressed air supply system is equipped with an air dryer to dry the compressed air. This prevents the accumulation of moisture in the pneumatic system. At relatively low temperatures, moisture can lead to crystal formation that damages valves and, in addition, to unwanted defects in the compressed air supply system and the pneumatic system. An air dryer contains a desiccant, usually a drying granulate, through which the compressed air flows in such a way that the drying granulate can absorb the moisture contained in the compressed air through adsorption. An air dryer can, if necessary, be designed as a regenerative air dryer.This can be achieved by passing compressed air from a reservoir or the air bellows through the drying granulate – usually in countercurrent, but sometimes also in parallel flow relative to the filling direction. The compressed air used to regenerate the air dryer is then released into the environment via the venting path. The pressure of the compressed air in the reservoir is considerably higher than the pressure of the compressed air flowing from the pneumatic system and, in particular, the air bellows of the air suspension system. The pressure within the reservoir is typically in the range of 12 bar to 18 bar, and the pressure of the compressed air discharged from the pneumatic system and, in particular, the air bellows is typically in the range of 0 bar to 12 bar.

[0006] When compressed air under reservoir pressure is vented from the air dryer volume or the main pneumatic line, considerable noise is generated due to the high pressures in the range of 12 bar to 18 bar. These noises are generally not masked by engine noise, particularly in electrically powered vehicles, and are therefore perceived as disturbing. There is therefore a need to reduce the noise generated during venting. At the same time, the venting of the pneumatic system, especially the air suspension bellows, must not be impeded in order to achieve rapid lowering times. For example, DE 39 19438 A1 shows a pneumatic system with a compressed air supply system and a consumer, such as an air suspension system. The compressed air supply system has a regenerative air dryer arranged in a main pneumatic line.Furthermore, an expansion tank is provided, which serves to absorb air from the emptying consumers and to discharge air to the air dryer during regeneration mode. As the compressed air flows in countercurrent from the consumer or the expansion tank toward the air dryer, it passes through a dryer throttle, which reduces the pressure through a correspondingly small flow diameter to allow moisture to be released from the drying granules. However, this dryer throttle increases the venting time required for the compressed air to escape from the consumer. In the case of an air suspension system as the consumer, for example, this leads to increased lowering times and thus to limitations in driving dynamics.

[0007] This is where the invention comes in, the object of which is to provide a pneumatic system, a compressed air supply system for a corresponding pneumatic system and a method for operating a pneumatic system, which enable a reduction in the venting noise when venting compressed air under reservoir pressure and at the same time avoid an impairment of the venting of the pneumatic system, in particular of the air bellows, and thereby ensure effective dryer regeneration.

[0008] The problem concerning the pneumatic system is solved in a first aspect of the invention by a pneumatic system according to claim 1.

[0009] With regard to the pneumatic system, the invention proposes a pneumatic arrangement arranged in the venting path, which comprises a bypass line with a bypass diameter and a switching and control actuator, wherein the bypass line branches off from a line section of the venting path with a venting diameter at a first connection point and reconnects to the line section at a second connection point. The invention further proposes that the bypass diameter be smaller than the venting diameter of the line section, and that the switching and control actuator has an actuator element arranged between the first connection point and the second connection point. It is defined that the venting diameter and the bypass diameter, which is smaller than the bypass diameter, are each effective diameters and not the absolute line diameters.The bypass line is therefore always open to flow, regardless of the switching and control state of the switching and control actuators. However, the bypass diameter slows down the compressed air flowing towards the vent connection. This reduces venting noise. Furthermore, the line section of the venting path with the larger venting diameter and the actuator element arranged in it enable rapid venting. The actuator element of the switching and control actuators allows control of the venting via the line section and thus of the resulting venting noise. This rapid venting enables effective regeneration of the air dryer. By appropriately controlling the actuator element, the line section with the venting diameter can be opened pneumatically so that flow can be permitted for rapid venting of the pneumatic system, in particular the air bellows.Compressed air flows through the bypass line as well as through the line section toward the vent connection or toward the environment. However, if venting of the pneumatic system is not required, but rather only the venting of compressed air under reservoir pressure, the switching and control actuator is preferably designed to block the line section by appropriately controlling the actuator element, so that the compressed air can flow exclusively via the bypass line to the vent connection or into the environment. Controlling the actuator element in this case is understood to mean both active control and control by omitting the provision of a control command, for example, a control current.Depending on the normal position of the actuator element, in which it remains, for example, in a de-energized or pressureless state, either an active control of the actuator element by applying a control current or a control pressure is necessary to pneumatically release the line section with the vent diameter, or a control by omitting or interrupting the supply of a control current or a control pressure. Further developments of the invention are specified in the dependent claims, which further develop the concept of the invention with regard to advantageous features within the scope of the task and with regard to further advantages.

[0010] Preferably, the actuator element is configured to selectively open or block the line section depending on at least one control variable that correlates to a pressure of the compressed air fed to the vent connection and / or to a vehicle speed. The actuator element thus opens or blocks the line section depending on at least one control variable and subsequently releases it again depending on the control variable. The pressure of the compressed air fed to the vent connection indicates whether the pressure is low, for example, 0 to 12 bar, as typically occurs within air bellows of an air suspension system, or whether the pressure is higher, in particular 12 to 18 bar, as typically occurs in the reservoir.If the pressure range is particularly between 0 and 12 bar, and thus a bellows venting process is involved, effective regeneration of the air dryer can be carried out and the compressed air can be routed through the larger vent line diameter. This allows for differentiation, indicating the need for rapid venting and thus the release of the line section. Furthermore, the inventors recognized that high vehicle speeds are associated with increased noise development due to driving noise. This already increased noise development simultaneously allows for increased noise development when venting the pneumatic system, without this being perceived as disturbing by the occupants or even being noticed by them.Thus, a control variable correlated with the vehicle speed can be used to cancel the line section's blockage if a predefined vehicle speed is exceeded, resulting in noise levels that mask the venting noise. In this case, reducing the speed of the compressed air flowing toward the vent connection or the environment by routing it through the bypass line with the bypass diameter is not necessary.

[0011] A suitably selected bypass diameter slows down the compressed air sufficiently. A maximum vent diameter within the appropriate range also allows for a sufficiently high venting speed and thus corresponding venting times for quickly lowering the vehicle body in air suspension systems.

[0012] Preferably, the pneumatic main line has a main line diameter upstream of the air dryer in the venting direction, and the bypass diameter is larger than the main line diameter, in particular 5% to 15% larger than the main line diameter. This prevents back pressure in the air dryer. The main line diameter is preferably in a range of 0.8 mm to 3.6 mm.

[0013] Preferably, the bypass diameter and the vent diameter together are larger than the main line diameter. The sum of the bypass diameter and the vent diameter is therefore larger than the main line diameter. This effectively prevents throttling losses.

[0014] Further preferred is a dryer throttle with a throttle diameter on the inlet side, with the bypass diameter being larger than the throttle diameter, in the pneumatic main line. This avoids throttling losses in the pneumatic main line with the line diameter.

[0015] More preferably, the vent line has a line diameter that is larger than the bypass diameter. A reduced diameter of the bypass line compared to the vent line slows the compressed air as it flows through the bypass line toward the vent connection. The line diameter is preferably at least 1.5 times, particularly preferably at least twice, the main line diameter. More preferably, the sum of the bypass diameter and the vent line diameter corresponds to at least one main line diameter of the pneumatic main line. This ensures efficient regeneration of the air dryer.

[0016] According to a preferred embodiment, the control variable is a control current, and the actuator element is an electromagnetically actuated switching valve. The switching valve is preferably a normally closed 2 / 2-way solenoid valve. Solenoid valves are characterized by fast response times. A normally closed 2 / 2-way solenoid valve provides an actuator element that blocks the line section in a normal state—i.e., a normally closed state—and only releases the line section when actuated with the control current. An electrical control variable in the form of a control current and an electrical actuation of the actuator element enable greater precision than a pneumatic control variable and a corresponding pneumatic actuation of the actuator element.

[0017] Preferably, the pneumatic system further comprises at least one pressure sensor for measuring a pressure in the pneumatic main line and / or the pneumatic system. The control current is provided when the pressure measured by the pressure sensor falls below a predefined threshold. Such a pressure sensor can reliably detect the pressure in the pneumatic main line and distinguish whether the air in the pneumatic main line and in particular in the air dryer is compressed air from the pneumatic system, in particular the air bellows, or whether it is compressed air from the reservoir, thus ensuring rapid venting of the compressed air from the air bellows. However, the actuator element can also be controlled as needed depending on a predefined pressure threshold, for example 12 bar, which customers perceive as acoustically disturbing.The pressure sensor is preferably connected to the electromagnetically actuated switching valve in a signal-conducting manner and is configured to provide a control current depending on the detected measured value. Alternatively or additionally, one or more of the pressure sensors are connected to a control unit, in particular an ECU, in a signal-conducting manner, wherein the control unit is configured to provide the control current.

[0018] Further preferably, the electromagnetically actuated switching valve is control-technically connectable to a control unit of the vehicle, and the control current is provided by the control unit when the vehicle speed exceeds a predefined threshold. Such a control unit, in particular an ECU, continuously monitors the vehicle speed. Controlling the actuator element in the form of an electromagnetically actuated switching valve depending on the vehicle speed thus enables reliable control and rapid venting via the line section only when the vehicle speed is sufficiently high, thus masking venting noises.According to a further preferred embodiment, the control variable is a control pressure and the actuator element is a pneumatically actuated valve, wherein the pneumatic arrangement comprises a control pressure line configured to supply the control pressure in the venting direction upstream of the pneumatically actuated valve from the pneumatic main line and / or the line section to the pneumatically actuated valve. By using a control pressure as the control variable, the pressure in the pneumatic main line or in the line section directly leads to actuation of the actuator element in the form of a pneumatically actuated valve. The pneumatic system, and in particular the pneumatic arrangement, is thus simplified, and pressure-dependent control takes place, thereby increasing the reliability of the pneumatic arrangement.Preferably, the pneumatically actuated valve is a mechanical valve that can be actuated using an air flow as the control variable. A mechanical valve is more robust, especially compared to solenoid valves. This is especially true for operation in frosty conditions, as icing has less of an impact on operation due to the higher opening energy.

[0019] Further preferably, the pneumatically actuated valve is a switching valve, in particular a 2 / 2-way valve, which is designed to block the line section when a control pressure above a predefined threshold is applied. Such a predefined threshold is coupled, in particular, to the pressure in the reservoir. If the pressure in the line section or in the pneumatic main line is equal to the reservoir pressure, a correspondingly high control pressure – exceeding the threshold – is applied, and the line section is blocked by the pneumatically actuated switching valve.In the preferred embodiment of the switching valve as a 2 / 2-way valve, this preferably has a spring which exerts a spring force in the direction of an open position of the 2 / 2-way valve, so that the line section is released until the pressure force applied by the control pressure to the 2 / 2-way valve and in particular to a piston arranged therein overcomes the spring force.

[0020] Preferably, the pneumatically actuated valve is a proportional valve, or the actuator element comprises another pneumatically actuated valve, which is a proportional valve. The proportional valve is designed to reduce a flow cross-section of the vent diameter depending on the applied control pressure. Thus, the velocity of the compressed air flowing through the line section is reduced by the proportional valve depending on the applied control pressure. Due to the higher control pressure, a high pressure in the pneumatic main line simultaneously leads to a greater reduction in the flow cross-section and thus to a greater reduction in the velocity of the compressed air flowing toward the vent connection or the environment.At the same time, such a proportional valve enables more precise control of the velocity of the outgoing compressed air, just enough to prevent unintentional noise. At the same time, it prevents unnecessary reduction in the flow velocity of, for example, compressed air that is only slightly above the pressure in the pneumatic system.

[0021] Further preferably, the pneumatic arrangement comprises a reservoir arranged upstream of the actuator element in the line section in the venting direction. Such a reservoir, which temporarily stores the applied compressed air, enables smaller fluctuations in the provision of a control pressure as a control variable and thus more precise control of the actuator element.

[0022] According to a preferred embodiment, the line section forms the vent line in sections. Thus, the line section and thus also the bypass line are integrated into the vent line or in the area of ​​the vent line, and the pneumatic system, in particular the vent path, is thus more compact.

[0023] According to a further preferred embodiment, the pneumatic assembly is arranged at the vent port. Arranging the pneumatic assembly at the vent port allows for easy retrofitting of existing pneumatic systems with such a pneumatic assembly and its connection to the vent port.

[0024] According to a further preferred embodiment, the venting path has a silencer arranged at the venting connection, and the pneumatic assembly extends at least partially through the silencer. Thus, the pneumatic assembly can be supplemented together with the silencer if necessary in pneumatic systems. Compressed air escaping through the pneumatic assembly thus exits in the area of ​​the silencer and is dampened by it, further reducing noise generation.

[0025] According to a further preferred embodiment, the vent line is a combined intake and exhaust line, and the line section forms the combined intake and exhaust line in sections. The diameters of the line section and the bypass line are adapted to the intake requirements of the compressor, which draws air from the environment via the combined intake and exhaust line. The pneumatic system is thus more compact overall.

[0026] In a second aspect, the invention relates to a compressed air supply system for supplying a pneumatic system, in particular an air spring system, with a compressed air connection to the compressor, a compressed air supply connection to the pneumatic system and a pneumatic main line between the compressed air connection and the compressed air supply connection with an air dryer and a venting path with a venting connection to the environment and a venting line leading from the pneumatic main line to the venting connection.The invention achieves the object mentioned above in the second aspect by means of a pneumatic arrangement arranged in the venting path, which comprises a bypass line with a bypass diameter and a switching and control actuator, wherein the switching and control actuator branches off from a line section of the venting path with a venting diameter at a first connection point and reconnects to the line section at a second connection point, and the switching and control actuator has an actuator element arranged between the first connection point and the second connection point. By means of such a pneumatic arrangement arranged in the venting path, the compressed air supply system according to the second aspect of the invention incorporates the advantages described above with regard to the first aspect of the invention.Embodiments and advantages described with reference to the first aspect of the invention are thus also embodiments and advantages of the compressed air supply system according to the second aspect of the invention.

[0027] In a third aspect, the invention relates to a vehicle, in particular a passenger car, with a pneumatic system according to the first aspect of the invention. By means of such a pneumatic system, the vehicle according to the third aspect of the invention incorporates the advantages described above with reference to the first aspect of the invention. Thus, embodiments and advantages described with reference to the first aspect of the invention are also embodiments and advantages of the vehicle according to the third aspect of the invention.

[0028] In a fourth aspect, the invention relates to a method for operating a pneumatic system, in particular a pneumatic system according to the first aspect of the invention. The initially stated object is achieved in the method according to the fourth aspect of the invention in that it comprises the steps:

[0029] Leading compressed air from a compressed air supply connection to a compressed air supply system, wherein the compressed air supply system has a compressed air connection to a compressor, the compressed air supply connection and a pneumatic main line between the compressed air connection and the compressed air supply connection with an air dryer and as well as a vent path with a vent connection to the environment and a vent line leading from the pneumatic main line to the vent connection,

[0030] Leading compressed air from the pneumatic main line to the venting path with a pneumatic arrangement which has a bypass line with a bypass diameter and a switching and control actuator, wherein the bypass line branches off from a line section of the venting path with a venting diameter at a first connection point and reconnects to the line section at a second connection point, and wherein the bypass diameter is smaller than the venting diameter and the switching and control actuator has an actuator element arranged between the first connection point and the second connection point, selectively blocking the line section by the actuator element,

[0031] Supplying compressed air via the bypass line with the first line diameter,

[0032] Release of the line section by the actuator element, in the event that a control variable does not exceed a predefined threshold, and

[0033] Passing compressed air over the pipe section.

[0034] By routing compressed air from the main pneumatic line to a venting path with a pneumatic arrangement that includes a bypass line and a switching and control actuator in a venting path, wherein the line section is selectively blocked or opened by an actuator element of the switching and control actuator, the method according to the fourth aspect of the invention utilizes the advantages described above with reference to the first aspect of the invention. The exemplary embodiments and advantages described with reference to the first aspect of the invention are thus also exemplary embodiments and advantages of the method according to the fourth aspect of the invention.

[0035] Embodiments of the invention will now be described below with reference to the drawings in comparison to the prior art, some of which is also shown. These are not necessarily intended to represent the embodiments to scale; rather, where useful for explanation, the drawings are schematic and / or slightly distorted. With regard to additions to the teachings immediately apparent from the drawings, reference is made to the relevant prior art. It should be noted that many modifications and changes to the form and detail of an embodiment can be made without departing from the general idea of ​​the invention. The features of the invention disclosed in the description, in the drawings and in the claims can be essential for the further development of the invention, both individually and in any combination.Furthermore, all combinations of at least two of the features disclosed in the description, the drawings, and / or the claims fall within the scope of the invention. The general idea of ​​the invention is not limited to the exact form or detail of the preferred embodiment shown and described below, nor is it limited to an object that would be limited compared to the object claimed in the claims. In the case of specified dimensioning ranges, values ​​within the stated limits are also intended to be disclosed as limit values ​​and can be used and claimed as desired.

[0036] Further advantages, features and details of the invention will become apparent from the following description of the preferred embodiments and from the drawing, which shows:

[0037] Fig. 1 shows a pneumatic system according to the prior art in a combined (bellows) venting and regeneration operation;

[0038] Fig. 2 shows a pneumatic system according to the prior art in a combined (accumulator) venting and regeneration mode; Fig. 3 shows a pneumatic system schematically according to a first embodiment during venting of a pneumatic system;

[0039] Fig. 4 shows the pneumatic system according to Fig. 3 when venting a reservoir;

[0040] Fig. 5 a compressed air supply system for a pneumatic system according to

[0041] Figs. 3 and 4 according to a first embodiment;

[0042] Fig. 6 shows a compressed air supply system for a pneumatic system according to Figs. 3 and 4 according to a second embodiment;

[0043] Fig. 7 shows a compressed air supply system for a pneumatic system according to Figs. 3 and 4 according to a third embodiment;

[0044] Fig. 8 shows a compressed air supply system for a pneumatic system according to a fourth embodiment;

[0045] Fig. 9 shows a compressed air supply system for a pneumatic system according to Figs. 3 and 4 according to a fourth embodiment;

[0046] Fig. 10 shows a method for operating a pneumatic system according to Figs. 3 and 4.

[0047] Fig. 1 and Fig. 2 show, by way of example, a pneumatic system 20 with a compressed air supply system 100 and a pneumatic system 200 in the form of an air spring system 201. The pneumatic system 20 shown corresponds to the prior art.

[0048] The compressed air supply system 100 is used to operate the pneumatic system 200.

[0049] For this purpose, the compressed air supply system 100 has a compressed air connection 1 and a compressed air supply connection 2 to the pneumatic system 200. The compressed air connection 1 is connected in this case to an intake connection 0, an intake line 111, an air filter 0.3 arranged upstream of the intake connection 0, and a compressor 101 arranged downstream of the intake connection 0. The compressor 101 is configured to provide compressed air 311 with a supply pressure Pv. For example, the compressor 101 is a compressor driven by a motor M. A first pneumatic connection is formed in this case with a pneumatic main line 112 between the compressed air connection 1 and the compressed air supply connection 2.

[0050] The compressed air supply system 100 further comprises a venting path 103 with a venting connection 3 and a second pneumatic connection, namely the venting line 113, which is pneumatically connected to the pneumatic main line 112 and the venting connection 3. An air dryer 102 is also arranged in the pneumatic main line 112. In the present case, the venting line 113 connects to the pneumatic main line 112 between the compressed air connection 1 and the air dryer 102. Venting takes place as required in a venting direction R via the pneumatic main line 112 and the venting line 113. A controllable venting valve 104 is provided in the venting line 113. The controllable vent valve 104 is presently an indirectly switched relay valve part of a solenoid valve arrangement 110 for indirectly switching a compressed air volume of the vent line 113 that can be filled from the pneumatic main line 112.The solenoid valve arrangement 110 has a control valve 107 in the form of a 3 / 2-way solenoid valve. The control valve 107 can be controlled via electrical control signals in the form of a voltage and / or current signal. When controlled, the control valve 107 can be moved from a normally closed position (not shown) to a pneumatically open position shown in Fig. 1 and Fig. 2, in which a pressure derived from the pneumatic main line 112 via a pneumatic control line 107.1 is passed on to the pneumatic control of the controllable vent valve 104 by means of a pilot line 104.1.

[0051] In the closed state (not shown), the control valve 107 separates the control line 107.1 and is pneumatically connected to the intake port 0 via a further pneumatic line 107.2 and can thus discharge compressed air 316 into the intake line 111.

[0052] A dryer throttle 102.1 is arranged in the pneumatic main line 112 upstream of the air dryer 102 in the venting direction R. The dryer throttle 102.1 is designed to expand the compressed air 313, 315 in countercurrent before flowing into the air dryer 102 only to such an extent that a sufficient venting time can be achieved when venting the pneumatic system 200 and thereby regenerating the air dryer 102, as shown in Fig. 1.

[0053] In this case, the control valve 107 is assigned a first accumulator 106, which is designed to receive compressed air 317 flowing from the pneumatic main line 112 through the control line 107.1. Compressed air 317 from the first accumulator 106 can be guided via the control valve 107, designed as a relay valve, and the vent valve 104 to the vent connection 3 and released into the environment A. The first accumulator 106 thus temporarily stores the compressed air 317 guided from the pneumatic main line 112 to the control valve 107 via the control line 107.1 until the control valve 107 is electrically actuated, so that the compressed air 317 from the first accumulator 106 can reach the vent valve 104. The first accumulator 106 is connected to the control valve 107 via a accumulator supply line 106.1.

[0054] In this case, the air suspension system 201 has, as compressed air receiver 220, a number of four so-called air spring bellows 223, 224, 225, 226, each of which is assigned to a wheel of a vehicle 1000 (not shown in detail) and forms an air spring of the vehicle 1000. The vehicle 1000 is, in particular, a passenger car 1100. Furthermore, the pneumatic system 20 has a reservoir 202 for storing readily available compressed air for the air spring bellows 223, 224, 225, 226. A solenoid valve 213, 214, 215, 216 is arranged upstream of each of the air bellows 223, 224, 225, 226, each of which serves as a level control valve for selectively opening and closing an air spring formed by an air bellows 223, 224, 225, 226. The solenoid valves 213, 214, 215, 216 are designed as 2 / 2-way valves. A reservoir valve 212 is arranged upstream of the reservoir 202 in a storage line 204. In this case, the reservoir valve 212 is a solenoid valve.The reservoir valve 212 is designed to selectively open and close the storage line 204 to store excess compressed air 315 from the gallery 211 in the reservoir 202. The storage line 204 is connected to the compressor 101 via a filling line 206. A quick-fill valve 109, which in this case is a 2 / 2-way solenoid valve, is arranged in the filling line 206. For rapid filling of the reservoir 202, the quick-fill valve 109 is designed to open the filling line 206 in a manner that allows flow of fluid through it. Thus, the reservoir 202 can be filled independently of the pressure supply through the pneumatic main line 112. The solenoid valves 213, 214, 215, 216, 217, and the reservoir valve 212 are connected to a common manifold, a pneumatic line forming gallery 211. Gallery 211 is pneumatically connected to the compressed air supply system 100 via the compressed air supply connection 2. The solenoid valves are present.

[0055] 213, 214, 215, 216 and the reservoir valve 212 are arranged in a valve block 210 with five valves. The solenoid valves 213, 214, 215, 216 and the reservoir valve 212 are shown in Fig. 1 in a de-energized state - the solenoid valves 213,

[0056] 214, 215, 216 and the reservoir valve 212 are formed as normally closed solenoid valves. Other modified embodiments, not shown here, can implement a different arrangement of the solenoid valves 213, 214, 215, 216 and the reservoir valve 212—fewer or more solenoid valves can also be used within the valve block 210.

[0057] Preferably, the pneumatic system comprises at least one pressure sensor 218 for measuring a gallery pressure PG of compressed air 313 in the gallery 211 of the pneumatic system 200.

[0058] Fig. 1 shows the pneumatic system 10 in a combined (bellows) venting and regeneration mode for venting the air spring bellows 223, 224, 225, 226 of the pneumatic system 200 while simultaneously regenerating the air dryer 102. Fig. 2 shows the pneumatic system 10 in a combined (reservoir) venting and regeneration mode for venting the reservoir 202 while simultaneously regenerating the air dryer 102. Venting the reservoir 202 is usually only necessary in the event of thermal fluctuations and thus expanding compressed air in the reservoir 202. Furthermore, venting the reservoir 202 due to the higher output pressure enables more efficient regeneration of the air dryer, so that the (reservoir) venting and regeneration operation shown in Fig. 2 is also advantageous in this case.

[0059] Fig. 3 and Fig. 4 show a pneumatic system 10 with a compressed air supply system 100 and a pneumatic system 200 in the form of an air spring system 201 according to a preferred embodiment of the invention. The pneumatic system 10 according to Figs. 3 and 4 differs from the pneumatic system 20 according to Figs. 1 and 2 in the design of the venting path 103. Identical or similar components have identical reference numerals in Figs. 1 and 2 as well as in Figs. 3 and 4, and to avoid repetition, reference is made to the above description of the compressed air supply system 100 and the pneumatic system 200 according to Figs. 1 and 2, and only differences, particularly with regard to the design of the venting section 103, are discussed.

[0060] Fig. 3 shows the pneumatic system 10 in an operating state in which the pneumatic system 200 and, in particular, the air bellows 223, 224, 225, 226 of the air suspension system 201 are being vented. In this state, the solenoid valves 213, 214, 215, 216, designed as normally closed 2 / 2-way valves, are energized and thus open a flow path for venting the air bellows 223, 224, 225, 226 via the gallery 211 to the pneumatic main line 112. The reservoir valve 212, which is also designed as a normally closed 2 / 2-way solenoid valve, does not release the storage line 204 in the state shown, so that no compressed air 315 can reach the pneumatic main line 112 from the reservoir 202.The vent valve 104 is in an open position due to the above-described control by the control valve 107, in which the vent valve 104 releases the vent line 113 of the vent path 103. The vent line 113 has a line diameter D.

[0061] Fig. 4 shows the pneumatic system 10 in an operating state in which the air dryer 102 is regenerated by compressed air 315 from the reservoir 202. The solenoid valves 213, 214, 215, 216 are in a de-energized state, so that they block the flow path between the air bellows 223, 224, 225, 226 and the pneumatic main line 112. The reservoir valve 212, on the other hand, is shown in an energized state, in which the storage line 204 is released so that compressed air 315 can flow from the reservoir 202 via the storage line 204 into the pneumatic main line 112 and finally to the air dryer 102, flowing through it in countercurrent toward the vent port 3. The control valve 107 controls the vent valve 104 in the manner described above, so that the vent valve 104 releases the vent line 113 so that it can flow pneumatically.

[0062] The pneumatic system 10 according to Fig. 3 and Fig. 4 differs from the prior art pneumatic system 20 shown in Fig. 1 and Fig. 2 by a pneumatic arrangement 130 arranged in the venting path 103, which has a bypass line 132 that branches off from a line section 113.1 of the venting path 103, in particular the venting line 113, at a first connection point A and reconnects at a second connection point A'. Furthermore, the pneumatic arrangement 130 comprises a switching and control actuator 134 with an actuator element 135 connected between the first connection point A and the second connection point A' for selectively opening or blocking the line section 113.1.

[0063] The actuator element 135 is designed to selectively open or block the line section 113.1 depending on at least one control variable S. The control variable S correlates to a pressure P of the compressed air 313, 315 fed to the vent connection 3 or to a vehicle speed v.

[0064] The pneumatic main line 112 has a main line diameter DH. The line section 113.1 also has a vent diameter Dmax, and the bypass line 132 has a bypass diameter Dmin. The bypass diameter Dmin is smaller than the vent diameter Dmax.

[0065] The dryer throttle 102.1 has an inlet-side throttle diameter Dp, whereby the bypass diameter Dmin is larger than the throttle diameter DH.

[0066] The actuator element 135 is preferably designed as a switching valve. To vent the pneumatic system 200, as shown in Fig. 3, the switching and control actuator 134 with the actuator element 135 is designed to release the line section 113.1 with the vent diameter Dmax. Compressed air 313 from the pneumatic system 200 thus flows both via the line section 113.1 with the vent diameter Dmax and via the bypass line 132 with the bypass diameter Dmin when the actuator element 135 is switched, as shown. Thus, rapid venting of the pneumatic system 200 can be realized, with the comparatively low gallery pressure PG of the compressed air 313 within the pneumatic system 200 resulting in acceptable noise levels. This can be ensured in particular when routing over line section 113.1 with the vent diameter Dmax.This ensures effective regeneration of the air dryer 102.

[0067] If, however, the air dryer 102 is regenerated by compressed air 315 from the reservoir 202, as shown in Fig. 4, the switching and control actuator 134 with the actuator element 135 is configured to block the line section 113.1 by appropriately switching the actuator element 135, which is designed as a switching valve. In this case, the switching of the actuator element 135 occurs by omitting the provision of a control variable, i.e., by "non-switching." In this case, compressed air 315 from the reservoir 202 is guided exclusively via the bypass line 132 with the bypass diameter Dmin to the vent connection 3. By guiding the compressed air 315 via the bypass line 132 with the bypass diameter Dmin, it is slowed down, so that the noise generated during venting is reduced.

[0068] Preferably, the switching valve 135 can be connected for control purposes to a control unit 400 of the vehicle 1000, wherein the control variable S is, for example, a control current Si (see Fig. 5) and is provided by the control unit 400 when a predefined threshold value Smax is exceeded by the vehicle speed v (see Fig. 5). Preferably, the switching and control actuator system 134 can also have a control unit or a control section (not shown), wherein the control section is configured to provide the control variable S.

[0069] Thus, the compressed air 315 is routed via the bypass line 132 with the bypass diameter Dmin to the vent port 3 only in cases where this is necessary for acoustic reasons. This avoids a reduction in the flow-through nominal diameter, which is unnecessary from an acoustic point of view, and thus a reduction in the efficiency during regeneration of the air dryer 102.

[0070] A silencer 500, which is also part of the venting path 103, is connected to the venting port 3. Preferably, the pneumatic arrangement 130 can also be arranged in the silencer 500 as a complete unit.

[0071] Preferably, the pressure sensor 218 for measuring the pressure P of the compressed air 313 in the gallery 211 is connected for control purposes to the control unit 400, wherein the control variable is provided depending on the measured pressure P. Alternatively or additionally, the pressure sensor 218 or an additional pressure sensor can also be arranged in the pneumatic main line 112 and connected for control purposes to the control unit 400, wherein the control variable is provided depending on the measured pressure P in the pneumatic main line 112. Figs. 5 to 9 show the compressed air supply system 100 with various preferred embodiments of the pneumatic arrangement 130.

[0072] In Fig. 5, the pneumatic arrangement 130 has an actuator element 135 designed as an electrically actuated switching valve 135.1. The switching valve 135.1 is preferably designed as a 2 / 2-way valve 135.1. The actuator element 135 is configured to selectively open or block the line section 113.1 depending on at least one control variable S. The control variable S correlates to a pressure P of the compressed air 313, 315 led to the vent connection 3 or to a vehicle speed v.

[0073] According to the embodiment shown in Fig. 5, the actuator element 135 is an electromagnetically actuated switching valve 135.1, which in this case is preferably designed as a normally closed 2 / 2-way solenoid valve. The control variable S is a control current Si, which correlates to the pressure P of the compressed air supplied to the compressed air connection 3 or to a speed v of the vehicle 1000. When the control current Si is applied, as shown in Fig. 5, a magnetic force FM is applied, which overcomes a spring force FF acting on the magnetically actuated switching valve 135.1.

[0074] According to the embodiment shown in Fig. 6, the actuator element 135 is a pneumatically actuated switching valve 135.2, which in this case is preferably designed as a normally open 2 / 2-way valve, with a control pressure line 136 of the switching and pneumatic arrangement 134, which connects to the pneumatic main line 112. The control variable S is a control pressure Sp, which is provided via the control pressure line 136 as a function of the pressure P in the pneumatic main line 112. In Fig. 6, the control pressure SP is greater than a predefined threshold value Smax, wherein the pneumatically actuated switching valve 135.2 is configured for this case to block the line section 113.1 so that it can flow pneumatically. The actuator element 135 is therefore shown in an actuated state. In this case, a pressure force Fp applied by the control pressure SP overcomes a spring force FF acting on the switching valve 135.2.

[0075] The embodiment shown in Fig. 7 differs from the one shown above in Fig.

[0076] 6 only in that the pneumatically actuated switching valve 135.2 connects to the line section 113.1 via the control line 136, and the control pressure Sp is determined by the pressure in the line section 113.1. Furthermore, a second accumulator 137 of the pneumatic arrangement 130 is arranged in the line section 113.1 for temporarily storing the compressed air 313, 315 located in the line section 113.1.

[0077] According to the embodiment shown in Fig. 8, the switching and control actuator 134 comprises an actuator element 135 designed as a pneumatically actuated proportional valve 135.3. The control variable S is also a control pressure SP, which is provided via a control pressure line 136 connecting to the line section 113.1. A second accumulator 137 is also arranged in the line section 113.1, which, corresponding to the second accumulator 137 shown in Fig. 7, temporarily stores the compressed air located in the line section 113.1.

[0078] The proportional valve 135.3 comprises a bypass branch 138.1 with a check valve 138 and a controllable throttle 139 in the line section 113.1. The check valve 138 can be flowed through exclusively in the direction of the vent port 3. The controllable throttle 139 is designed to reduce its flow cross-section—and thus a flow cross-section Q of the line section 113.1—depending on the control pressure Sp and to completely block it when a threshold value Smax is exceeded. The check valve 138 is designed to open depending on the pressure in the event that the control pressure SP exceeds the threshold value Smax. The bypass branch 138.1 with the check valve 138 also has the bypass diameter Dmin.

[0079] The embodiment of the compressed air supply system 100 shown in Fig. 9 differs from the above embodiment shown in Fig. 5 only in that the vent line and the intake line are preferably designed as a combined intake and vent line 114 to a combined intake and vent connection 0 / 3 and the vent path 103. The bypass diameter Dmin is adapted to the requirements of the compressor 101 so that a sufficient compressed air flow can be sucked in.

[0080] Furthermore, the electrically actuated switching valve 135.1 is preferably a first electrically actuated switching valve 135.1, and the pneumatic arrangement 130 has a second electrically actuated switching valve 135.2, which is preferably designed as a 2 / 2-way valve 135.1. The second electrically actuated switching valve 135.2 is configured to selectively open or close the bypass line 132 depending on at least the control variable S. This makes the control of the pneumatic arrangement 130 more precise and increases system reliability. It should be understood that such a second electrically actuated switching valve 135.2 can also be provided as a combined intake and vent line 114, regardless of the design of the vent line and the intake line.

[0081] Fig. 10 shows a method 2000 for operating a pneumatic system 10, as shown, for example, in Figs. 3 and 4. The method 2000 comprises supplying compressed air from a pneumatic system 200 to a compressed air supply system 100 in step 2100, wherein the compressed air supply system 100 is designed according to the embodiment shown in Figs. 3 and 4. Furthermore, the method 2000 comprises guiding compressed air 313, 315 from the pneumatic main line 112 to the venting path 103 with a pneumatic arrangement 130 shown in Figs. 3 to 9 in step 2200. Especially since the pneumatic arrangement 130 is designed as described above, in a further step 2300 the line section 113.1 is selectively blocked or opened by the actuator element 135 of the switching and control actuator 134 depending on the control variable S, in the event that the control variable S exceeds a predefined threshold value Smax, such as a threshold value.In this case, compressed air 315 is routed through the bypass line 132 with the bypass diameter Dmin in a further step 2400. Alternatively, the line section 113.1 is released by the actuator element 135 in a further step 2500 if the control variable S does not exceed the predefined threshold value Smax, and additionally, in a further step 2600, compressed air 313 is also routed through the line section 113.1.

[0082] In other words, the threshold value Smax is determined depending on acoustic effects, i.e., either depending on the speed and associated acoustic effects that mask any venting noise, or on the pressure of the compressed air being vented, which determines the noise level during venting. Reference symbol (part of the description)

[0083] 0 intake connection

[0084] 0 / 3 combined intake and exhaust connection

[0085] 1 compressed air connection

[0086] 2 compressed air supply connection

[0087] 3 vent connection

[0088] 0.3 air filter

[0089] 10 pneumatic system

[0090] 100 compressed air supply system

[0091] 101 compressors

[0092] 102 air dryers

[0093] 102.1 Dryer choke

[0094] 103 Ventilation path

[0095] 104 vent valve

[0096] 104.1 Pilot control line

[0097] 105 Check valve

[0098] 106 (first) memory

[0099] 106.1 Storage supply line

[0100] 107 Control valve

[0101] 107.1 Control line

[0102] 107.2 pneumatic line

[0103] 109 Quick-fill valve

[0104] 110 Solenoid valve arrangement

[0105] 111 Intake line

[0106] 112 pneumatic main line

[0107] 113 Ventilation line

[0108] 113.1 Line section

[0109] 114 combined intake and exhaust line

[0110] 130 Pneumatic arrangement

[0111] 132 Bypass line

[0112] 134 Switching and control actuators

[0113] 135 Actuator element 135.1 first switching valve

[0114] 135.2 second switching valve

[0115] 136 Control pressure line

[0116] 137 second storage

[0117] 138 Check valve

[0118] 138.1 Bypass branch

[0119] 139 controllable throttle

[0120] 200 pneumatic system

[0121] 202 Reservoir

[0122] 204 storage line

[0123] 206 Filling line

[0124] 210 valve block

[0125] 211 Gallery

[0126] 212 Reservoir valve

[0127] 213, 214, 215, 216 solenoid valves

[0128] 218 pressure sensor

[0129] 220 compressed air consumers

[0130] 223, 224, 225, 226 air spring bellows

[0131] 311 Compressed air from the compressor

[0132] 313 Compressed air from the gallery

[0133] 315 Compressed air from the reservoir

[0134] 316 Compressed air in the intake line

[0135] 317 Compressed air in the control pressure line

[0136] 400 control unit

[0137] 500 silencers

[0138] 1000 vehicles

[0139] 1110 passenger cars

[0140] 2000 procedures

[0141] 2100 Providing compressed air with a supply pressure

[0142] 2200 Filling the reservoir

[0143] 2300 Drying of compressed air by air dryer

[0144] 2400 Supplying the pneumatic system with compressed air

[0145] 2500 Venting the pneumatic system 2600 Regenerating the air dryer

[0146] A environment

[0147] FF spring force

[0148] Fp compressive force

[0149] M engine

[0150] P pressure

[0151] PG Gallery Print

[0152] S control variable

[0153] Sp control pressure

[0154] Si control current v speed

[0155] Q flow cross-section

[0156] R Ventilation direction

[0157] Dmin bypass diameter

[0158] DMax vent diameter

[0159] D Cable diameter

[0160] DH main line diameter

[0161] DR throttle diameter

Claims

Patent claims 1. A pneumatic system (10) for a vehicle (1000), in particular a passenger car (1110), comprising a compressor (101) for providing compressed air (311); a pneumatic system (200), in particular an air spring system (201), with at least one compressed air receiver (220); a compressed air supply system (100) for supplying the pneumatic system (200), with a compressed air connection (1) to the compressor (101), a compressed air supply connection (2) to the pneumatic system (200), a pneumatic main line (112) between the compressed air connection (1) and the compressed air supply connection (2) with an air dryer (102), and a venting path (103) with a venting connection (3) to the environment (A) and a venting line (113) leading from the pneumatic main line (112) to the venting connection (3); and a reservoir (202) connected to the compressed air supply connection (2) via a storage line (204);characterized by a pneumatic arrangement (130) arranged in the venting path (103), which has a switching and control actuator (134) and a bypass line (132) with a bypass diameter (Dmin), which branches off at a first connection point (A) from a line section (113.1) of the venting path (103) with a venting diameter (Dmax) and reconnects to the line section (113.1) at a second connection point (A'), wherein the bypass diameter (Dmin) is smaller than the venting diameter (Dmax) and the switching and control actuator (134) has an actuator element (135) arranged between the first connection point (A) and the second connection point (A') for selectively opening or blocking the line section (113.1); 2. Pneumatic system (10) according to claim 1, wherein the actuator element (135) is configured to selectively open or block the line section (132) depending on at least one control variable (S). which correlates to a pressure (P) of the compressed air (313, 315) fed to the vent connection (3) and / or to a vehicle speed (v).

3. Pneumatic system (10) according to claim 2, wherein the pneumatic main line (112) has a main line diameter (DH) upstream of the air dryer (102) in a venting direction (R) and the bypass diameter (Dmin) is larger than the main line diameter (DH), in particular is 5% to 15% larger than the main line diameter (DH), and / or wherein in the pneumatic main line (112) there is a dryer throttle (102.1) with an inlet-side throttle diameter (DR) and the bypass diameter (Dmin) is larger than the throttle diameter (DH), and / or wherein the bypass diameter (Dmin) and the vent diameter (Dmax) together are larger than the main line diameter (DH).

4. Pneumatic system (10) according to claim 1, 2 or 3, wherein the vent line (113) has a line diameter (D) which is larger than the bypass diameter (Dmin) and is preferably at least 1.5 times and in particular at least 2 times the main line diameter (DH).

5. Pneumatic system (10) according to one of claims 2 to 4, wherein the control variable (S) is a control current (Si) and the actuator element (135) is an electromagnetically actuated switching valve (135.1).

6. Pneumatic system (10) according to claim 5, further comprising: at least one pressure sensor (218) for measuring a pressure (P) in the pneumatic main line (112) and / or the pneumatic system (200), wherein the control current (Si) is provided when the measured pressure (P) falls below a predefined threshold value (Smax), and / or wherein the electromagnetically actuated switching valve (135.1) is control-technically connectable to a control unit (400) of the vehicle (1000) and the control current (Si) is controlled by the control unit (400) when a predefined nated threshold value (Smax) is provided by the vehicle speed (v).

7. Pneumatic system (10) according to one of claims 2 to 4, wherein the control variable (S) is a control pressure (Sp) and the actuator element (135) is a pneumatically actuated valve (135.2, 135.3), and wherein the pneumatic arrangement (130) comprises a control pressure line (136) which is designed to supply the control pressure (Sp) from upstream of the pneumatically actuated valve (135.2, 135.3) in the venting direction (R) from the pneumatic main line (112) and / or from the line section (113.1) to the pneumatically actuated valve (135.2, 135.3).

8. Pneumatic system (10) according to claim 7, wherein the pneumatically actuated valve (135.2) is a switching valve (135.2) which is designed to block the line section (113.1) when a control pressure (Ps) above a predefined threshold value (Smax) is applied.

9. Pneumatic system (10) according to claim 7, wherein the pneumatically actuated valve (135.3) is a proportional valve (135.3) which is designed to reduce a flow cross-section (Q) of the line section (113.1) depending on the applied control pressure (Ps).

10. Pneumatic system (10) according to one of claims 7 to 9, wherein the pneumatic arrangement (130) has a reservoir (137) arranged in the line section (113.1) upstream of the actuator element (135) in the venting direction (R).

11. Pneumatic system (10) according to one of the preceding claims, wherein the line section (113.1) partially forms the vent line (113).

12. Pneumatic system (10) according to one of claims 1 to 11, wherein the pneumatic arrangement (130) is connected to the vent connection (3).

13. Compressed air supply system (100) for supplying a pneumatic system (200), in particular an air spring system (201), with a compressed air connection (1) to the compressor (101), a compressed air supply connection (2) to the pneumatic system (200) and a pneumatic main line (112) between the compressed air connection (1) and the compressed air supply connection (2) with an air dryer (102) and a venting path (103) with a venting connection (3) to the environment (A) and a venting line (113) leading from the pneumatic main line (112) to the venting connection (3), characterized by a pneumatic arrangement (130) arranged in the venting path (103), which has a switching and control actuator (134) and a bypass line (132) with a bypass diameter (Dmin), which at a first connection point (A) from a line section (113.1) of the venting path (103) with a venting diameter (Dmax) branches off and reconnects to the line section (113.1) at a second connection point (A'), wherein the bypass diameter (Dmin) is smaller than the venting diameter (Dmax) and the switching and control actuator (134) has an actuator element (135) arranged between the first connection point (A) and the second connection point (A') for selectively opening or blocking the line section (113.1).

14. Vehicle (1000), in particular a passenger car (1110), with a pneumatic system (10) according to one of claims 1 to 12 and / or a compressed air supply system according to claim 13.

15. Method (2000) for operating a pneumatic system (10), in particular a pneumatic system (10) according to one of claims 1 to 12, comprising the steps: Leading (2100) compressed air (313, 315) from a compressed air supply connection (2) to a compressed air supply system (100), wherein the compressed air supply system (100) has a compressed air connection (1) to a compressor (101), the compressed air supply connection (2) and a pneumatic main line (112) between the compressed air connection (1) and the compressed air supply connection (2) with an air dryer (102) and as well as a vent path (103) with a vent connection (3) to the environment (A) and a vent line (113) leading from the pneumatic main line (112) to the vent connection (3), Guiding (2200) compressed air (313, 315) from the pneumatic main line (112) to the venting path (103) with a pneumatic arrangement (130) which has a bypass line (132) with a bypass diameter (Dmin) and a switching and control actuator (134), wherein the bypass line (132) branches off at a first connection point (A) from a line section (113.1) of the venting path (103) with a venting diameter (Dmax) and reconnects to the line section (113.1) at a second connection point (A'), and the switching and control actuator (134) has an actuator element (135) arranged between the first connection point (A) and the second connection point (A'), selective blocking (2300) of the line section (113.1) by the Actuator element (135), Leading (2400) compressed air (315) via the bypass line (132) with the bypass diameter (Dmin), Released (2500) of the line section (113.1) by the actuator element (135), in the event that a control variable (S) does not exceed a predefined threshold value (S max ), Leading (2600) compressed air (313) over the line section (113.1).

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