DE102020103036B3 - Pneumatic mass flow divider for an air suspension system of a vehicle - Google Patents

Abstract

The invention relates to a pneumatic mass flow divider (10) for a pneumatic vehicle spring system with an inlet (12) with an opening cross section (14). It is proposed that two outlets (16, 18) each have an opening cross section (20, 22) are, with a mass flow (24) that can be introduced into the inlet (12), evenly distributed or adjustable unevenly distributed as partial mass flows (25a, 25b) in the two outlets (16, 18), with a maximum of the pressures occurring in the partial mass flows (25a, 25b) is lower than a pressure of the mass flow (24) in the inlet. Furthermore, a method for dividing a pneumatic mass flow is disclosed.

Description

The invention relates to a pneumatic mass flow divider for an air suspension system of a vehicle with an inlet and two outlets according to the preamble of claim 1.

The invention also relates to a method for dividing a pneumatic mass flow according to the preamble of claim 12.

STATE OF THE ART

Pneumatic vehicle suspension systems for vehicles, in particular for cars and trucks, are known from the prior art, which allow adjustable suspension of the vehicle. Pneumatic air suspension systems are used, for example, in the area of a front axle or rear axle of a vehicle for the adjustable suspension of vehicle wheels. By activating the pneumatic system, the front axle or the rear axle or individual air springs of wheels can be activated, for example to achieve more ground clearance for the vehicle or, depending on the driving situation, a different suspension behavior. A chassis can also be lowered to make it easier to get out of the vehicle.

For this purpose, air suspensions with different pressure levels are arranged on the front and rear axles of a vehicle. Because of the different pressure levels, with the air suspension system from the prior art it is only possible to raise or lower the front axle and the rear axle sequentially, axle by axle. As a result, however, the vehicle is tilted out of its normal position, which results in a so-called "ship rocking effect". This has a negative effect on the comfort of the occupants. Furthermore, it may be necessary to provide additional control systems in order to eliminate the tilting from the normal position as far as possible.

In addition, to increase the capacity of an air dryer, it may be desirable to split an air flow into compressed air and to pass it through two or more air dryer units connected in parallel in order to remove moisture from the compressed air. An intended division should also be possible with different properties and pressure ratios of the air dryer units. So far, an identical air flow distribution can only be achieved with an exactly identical geometric, i.e. symmetrical design of the air dryer units and identical back pressure levels.

In the DE 11 2018 000 542 T5 describes a pneumatic suspension system for a vehicle, wherein at the outlet of an air compressor a compressed air supply line is divided into two partial compressed air supply lines for supplying the right and left suspension struts of the vehicle. A 50:50 division of the mass flow of the compressed air supply line takes place at a connection point in which an inlet is divided into two processes. This enables a static compressed air branch.

In addition, the pamphlets show DE 41 04 322 A1 and DE 82 36 395 U1 , which both describe hydraulic mass flow distributors, which are referred to as flow dividers or priority valves, and which are suitable for dividing a hydraulic mass flow for an air suspension system of a vehicle. In the DE 82 36 395 U1 it is also described that the priority valve is designed to supply two consumers with a split mass flow and, if the pressure difference exceeds a limit difference, to shut off the consumer with a lower pressure and to supply the consumer with the entire mass flow with a higher pressure.

The object of the invention is therefore to propose a pneumatic device or a method by means of which the comfort for the occupants of a vehicle can be improved. A further object of the invention is to eliminate as far as possible a deflection from the normal position of a vehicle when lowering or raising the front axle and rear axle. A further object of the invention is to enable parallel air drying of the same amounts of air flow even with differently designed air dryer units or with different counter pressures in air suspension systems

This object is achieved by a pneumatic mass flow divider and a method according to the independent claims. Advantageous further developments of the invention are the subject of the subclaims.

DISCLOSURE OF THE INVENTION

The invention relates to a pneumatic mass flow divider with an inlet with an opening cross section.

It is proposed that at least two outlets, each with an opening cross-section, are included, with a mass flow that can be introduced into the inlet being evenly distributed in the at least two outlets or adjustable unevenly distributed as partial mass flows, with a maximum of the pressures of the partial mass flows being less than one Is the pressure of the mass flow in the inlet. In this respect, there is a positive admission pressure difference between the inlet and the two or more processes of the mass flow divider. Compressed air subsystems such as vehicle compressed air springs, air dryers, compressed air storage, etc. are connected to the processes. The distribution to the compressed air subsystems takes place independently of a counterpressure which prevails in each of the two processes and which can in particular be different. This makes it possible to ensure that a predetermined amount of the mass flow is achieved in a first sequence and a second sequence, even with different back pressure ratios. In particular, in this case too, both processes can be equally stressed or flooded in the same way. It is also possible to route different mass flows through the first or second process in a predefinable manner.

If the processes are connected to different pressure levels, for example, different mass flows can be introduced into the processes in a targeted manner in order to achieve a predetermined or coordinated behavior for both pressure levels.

With a pneumatic mass flow divider according to the invention, in the field of vehicle air suspension technology, it is possible, for example, to raise or lower a vehicle in parallel. In this way, the "ship rocking effect" in particular can be eliminated. This is achieved in particular in that the front axle and the rear axle can be raised or lowered in parallel by the pneumatic mass flow divider.

In the following, two processes are assumed in each case, but the mass flow divider can also have three or more processes and distribute a mass flow equally across all processes.

The mass flow that flows through the first outlet is preferably dependent on the mass flow that flows through the second outlet. This can be achieved, for example, in that the processes are controlled or regulated as a function of one another. It is also conceivable that the pneumatic mass flow divider comprises more than two processes.

An inlet line can be understood as an inlet. A drain line can also be understood as a drain. The opening cross-sections can be circular line cross-sections, for example.

In the inflow there is an overpressure with respect to a maximum of the pressures of the partial mass flows of the processes in all operating modes.In other words, the mass flow in the inflow has a first pressure that is greater than a maximum of the pressures of the mass flows of the processes in all operating modes, i.e. use cases is. This creates a pre-pressure as overpressure. The admission pressure difference can preferably be 10% or more, in particular 20% or more, a maximum of the pressures of the outlets of the mass flow divider. It has been shown experimentally that an increased admission pressure difference leads to a more stable distribution of the mass flows, but that the energetic efficiency of the compressed air system suffers as a result. From a supercritical pressure situation of approx. 10% overpressure difference, a practically stable mass flow distribution can be achieved even with varying process pressures of the connected sub-compressed air systems. The overpressure difference also depends on the flow cross-sections or the mass flow variables. When designing the inlet pressure, a compromise has to be found between the level of the dynamic pressure (= inefficiency) and the inaccuracy of the mass flow division (if the pressure difference is too low). The design can be coordinated very well within a narrow mass flow tolerance range, i.e. with fixed operating points of the connected compressed air systems using static throttles. However, not all possible operating modes of the air suspension system can therefore be optimally designed within a mass flow divider implementation.

According to the invention, the inlet is connected to the two outlets via at least one control element. The regulating element preferably regulates the mass flow between the inlet and the two or more outlets. The control element can regulate the two processes as a function of one another. This can mean, for example, that an increase in the opening cross section of the first outlet entails a reduction in the opening cross section of the second outlet. The two processes can also be regulated independently of one another. This can be done, for example, by two independent control elements.

In a preferred embodiment, the control element can be at least one throttle valve. The throttle or the throttle combination can have fixed cross-sectional ratios, in particular throttle cross-sections of the same size, and thus have a static cross-sectional distribution. This design can be referred to as a static throttle combination or a static mass flow divider. Alternatively, a throttle valve can be arranged as a proportional valve on each outlet. Furthermore, the two processes can be controlled via a common, proportionally working and self-regulating 2-way throttle valve. This embodiment can be referred to as a dynamic throttle combination or as a dynamic mass flow divider. The throttle valve can comprise a throttle piston which, for example, spring-loaded, increases or decreases the opening cross-section depending on the pressure difference. By With a controllable throttle combination, different pressure ratios of the two or more connected compressed air systems can be regulated very well and an adapted mass flow distribution can be achieved even with varying process pressures in the individual compressed air systems.

In a preferred embodiment, the control element can be at least one throttle, in particular a throttle combination. A throttle combination can consist of two throttles, for example, with one throttle being assigned to a drain. The two chokes can be connected in parallel. The mass flow that flows through the respective throttle is preferably dependent only on the pressure of the mass flow in the inlet and on the system pressure at the outlet of each throttle, i.e. the pressure difference and the cross-sections of the throttles. This makes it possible in particular that the pressures of the mass flow in the processes can be varied without the mass flow changing. This can preferably also be achieved in that there is a pressure difference between the pressure of the mass flow in the inlet and the pressure of the mass flow in the outlets. The pressure in the inlet is preferably higher than in the outlets, so that an overpressure difference arises between the inlet and each outlet. There can consequently be a so-called pre-pressure or overpressure. The pre-pressure or overpressure is consequently higher than an outlet pressure. The mass flow can be distributed in a targeted manner by varying the throttle cross-sections.

In a preferred embodiment, the mass flow division can take place more precisely the higher the pressure difference. A pressure difference that is as high as possible can be achieved, for example, in that a ratio between a throttle diameter and the possible mass flow of a pressure wave is matched in such a way that a type of pressure cushion is created in front of the throttle. A compressor can, for example, be operated at a higher pressure level than is necessary due to the maximum pressures to be generated in the processes. When designing the components, a compromise can be found between a level of dynamic pressure and an accuracy of the mass flow division, in order to find a compromise between an inefficiency of the compressor and an inaccuracy of the mass flow division. In a preferred embodiment, a pre-pressure of at least 5% is preferred. 10%, in particular 20% or more, for example 5 bar to 10 bar, in particular 7 bar, above the initial pressure.

In a preferred embodiment, the regulating element can be designed as a displaceable piston, the two opening cross-sections of the throttle processes each being at least partially, in particular antiparallel, being able to be opened or closed by moving the piston. The piston can preferably have a length such that a first opening cross section of the first drain is completely covered by the length of the piston and a second opening section of the second drain is completely open, or both opening sections are partially, in particular 50%, covered. The mass flow through the opening cross-section of the respective outlet can therefore preferably be influenced by moving the piston.

Since the piston works with a pressure drop at the corresponding throttles, it is just as important with this mass flow divider to maintain a certain pre-pressure difference. The pre-pressure, and the resulting pressure drop across the throttle, should be so high that enough force can be generated on the piston to move it. A sensitive, i.e. smooth-running piston can work with very low pressure differences, but is complex to manufacture. However, this means that small pressure differences can be sufficient, and thus the inlet pressure can be reduced, which in turn is good for energy efficiency. Conversely, the more difficult the piston is, the more pre-pressure is required, so that the efficiency deteriorates, but the manufacturing costs are lower.

In a preferred embodiment, the piston can have at least one spring, in particular two springs, at each end of the piston, the piston being resettable, in particular self-resetting, into a neutral starting position by the at least one spring. In an initial position, the piston can, for example, be located centrally between the two outlets, with both opening cross-sections being covered to the same extent. Both opening cross-sections are preferably covered by 50%, for example. In the case of a deflected position from the starting position, one opening cross section can therefore be made larger than the other. By changing the opening cross-sections, the mass flow can be reduced or increased. If both processes are reached by one piston, a reduction in the mass flow at one process leads to an increase in the mass flow at the other process. The piston can preferably settle in such a way that both processes reach the same air mass. The following parameters can help to make the piston smoother, i.e. more sensitive: Reduction of the spring force, reduction of kinetic friction, increased piston area, increased admission pressure.

In a preferred embodiment, the piston can be arranged orthogonally between and with respect to the inlet and the two outlets be, in particular be arranged orthogonally with respect to a flow direction of the mass flow. As a result, a change in the opening cross-section of the drains can be achieved particularly advantageously by moving the piston. Particularly advantageously, a spring at one end of the piston in each case enables the piston to oscillate in such a way that the same air mass reaches the first and the second process.

In a preferred embodiment, the two processes can each be connected to at least one further component, the at least two components preferably having different pressure levels. The two components can be arranged at different positions in space, for example in a vehicle, and operated by just one compressor. The components can be compressed air actuators such as air springs, or other actuators, but also sinks such as compressed air reservoirs or treatment components such as air dryers, noise dampers, valves, etc. This is possible because the pneumatic mass flow divider according to the invention can be arranged between the compressor and the two components and can be connected by the two processes, and can thereby divide the mass flow accordingly. In this way, the load on a component can be reduced and a constant mass flow can be achieved for all components.

In a preferred embodiment, a first sequence can be connected to a front axle of an air suspension chassis and a second sequence can be connected to a rear axle of the air suspension chassis. For example, the pneumatic mass flow divider can be integrated into an air suspension system. A pneumatic mass flow divider according to the invention can be used to divide the flow in a vehicle. If the two processes are connected to the rear axle or front axle of a vehicle, the vehicle can, for example, be raised or lowered without tilting from the zero position. This is achieved in that the front axle and the rear axle are raised in parallel by a pneumatic mass flow divider according to the invention. The axes can be raised or lowered by 30-50 mm, in particular 40 mm, for example.

As an alternative or parallel to the aforementioned exemplary embodiment, a first outlet of the mass flow distributor can be connected to an inlet of a drying chamber of an air dryer and a second outlet can be connected to an inlet of a second drying chamber of the air dryer. This enables increased dryer performance by distributing the mass flow over several, parallel arranged dryer chambers, so that an air dryer can be built with a small volume or vented less often. Ideally, the dryer chambers are designed to be geometrically symmetrical to one another.

In a preferred embodiment, the two opening cross-sections of the outlets can have the same cross-sectional area in terms of area. It is also conceivable that the opening cross-sections have different cross-sectional areas in terms of area. In particular, it is made possible to adapt the two processes specifically to different pressure levels.

In a preferred embodiment, the opening cross-section of the inlet can have a cross-sectional area which, in terms of area, corresponds to a cross-sectional area of a sum of the two opening cross-sections of the outlets, or is greater than this sum. This enables the pneumatic mass flow divider to work particularly effectively and in an energy-saving manner.

The invention also relates to a method for dividing a pneumatic mass flow. For example, a pneumatic mass flow divider according to the invention can be used for the method.

It is proposed that a mass flow from a feed line with a cross-sectional area is proportionally divided as partial mass flows and released into two outlets, each with a cross-sectional area, whereby the two outlets can be connected to different pressure levels, and in the inlet an overpressure with respect to a maximum of the pressures of the Partial mass flows of the processes are present. The same features and advantages apply to the method according to the invention as already explained with regard to the pneumatic mass flow divider according to the invention.

For example, the mass flow in the feed can have a first pressure which is greater than a maximum of all pressures occurring in the mass flows of the outlets. In this way, in particular, a form, as described with regard to the mass flow divider, can be generated. The pre-pressure can be at least 5%, preferably 10%, in particular 20% above the maximum pressure occurring in a connected compressed air subsystem. The higher the admission pressure, the more stable a desired mass flow distribution can be guaranteed by the mass flow divider.

Furthermore, there can be an overpressure in the inlet with respect to the maximum of the pressures of the partial mass flows of the outlets. As a result, a type of pressure cushion can particularly advantageously build up in the area of the control element.

According to the invention, a regulating element between the inlet and the outlet, the mass flow between the inlet and the respective outlet, can be regulated in the method. The regulating element can be designed, for example, as a throttle combination and / or as a 2-way throttle valve.

An active control element is also conceivable, in which an electrically controllable, e.g. electromechanical 2-way proportional valve as a throttle valve based on flow sensors can achieve active control of the air distribution.

In a preferred embodiment of the method, the control element can be designed as a displaceable piston of a self-adjusting and proportionally operating throttle valve, the piston being held in a central position by means of at least one spring, in which the cross-sectional areas of the outlets are each 50% open. The piston is preferably arranged orthogonally to the direction of flow of the mass flow. As a result, the mass flow in the opening cross-sections of the drains can be controlled particularly advantageously by the piston alone. The middle position can be defined as the starting position with a 50:50 opening of the two drainage cross-sections.

In a preferred embodiment, at least two different pressure cushions can rest on the piston, the piston being able to be deflected from the central position by the different pressure cushions, whereby the respective opening cross-sections of the processes can be changed. Since the piston reacts preferentially to a pressure drop at a throttle or an outlet, it is advantageous if a pre-pressure is generated in the supply line. It is advantageous if the admission pressure and the resulting pressure drop at the throttle or the outlet are high enough so that enough force can be generated on the piston. As a result, the piston can be moved particularly advantageously.

In a preferred embodiment, a sensitive, i.e. smooth-running piston can be used for the throttle valve, which can work even with very small pressure differences. Advantageously, only a small pre-pressure then has to be generated in the case of small pressure differences, whereby the efficiency can be increased further. A sensitive piston can be achieved, for example, in that the springs have low spring forces, the piston can move with little friction and / or the piston has as large a piston area as possible. With a very sensitive piston system, only low initial pressures are required. A reduced inlet pressure difference in turn means that valve cross-sections can be designed larger, and thus larger mass flow ranges can be covered, i.e. different operating modes of the air pressure system such as lowering, lifting simultaneously or sequentially, etc. The energetic efficiency of the air pressure system can be optimized.

In a preferred embodiment, the different pressure cushions can result from the outflowing partial mass flows of the processes, the piston being displaced in the direction of the lower pressure cushion by the spring mounting and reducing the opening cross-section of the process located there.

In a preferred embodiment, the piston can level out in such a way that a partial mass flow of the same amount can flow through in both opening cross-sections of the two outlets.

Mass flow fluctuations caused by the compressor or the downstream compressed air systems can be balanced with a dynamic mass flow divider in a more qualitative and loss-free manner than with a static mass flow divider. When using a static mass flow divider, there is an operating point at which the mass flow divider works optimally, i.e. it sets the desired mass flow ratio constantly. When using a dynamic mass flow divider, the inlet pressure can be lower than with a static mass flow divider, provided the mechanics are sufficiently smooth, i.e. sensitive, or an active control component with sensors and electrically adjustable proportional throttles is used. Energy-efficient operation can then be achieved.

Figure list

Further advantages emerge from the present description of the drawings. Exemplary embodiments of the invention are shown in the drawings. The drawings, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations.

• 1 eine Fahrzeug beim Anheben der Vorder- bzw. Hinterachse aus dem Stand der Technik;
• 2 eine Fahrzeug beim parallelen Anheben der Vorder- und Hinterachse mit einem erfindungsgemäßen Massenstromteiler;
• 3 einen Lufttrockner mit parallel geschalteten Lufttrocknerkammern und einem vorgeschalteten Massenstromteiler;
• 4 eine Prinzipdarstellung einer Ausführungsform eines erfindungsgemäßen Massenstromteilers;
• 5 eine erste Ausführungsform eines erfindungsgenäßen Massenstromteilers mit einem selbstregulierenden Drosselventil;
• 6 eine weitere Ausführungsform eines erfindungsgemäßen Massenstromteilers mit einer Drosselkombination.

It shows:

• 1 a vehicle when lifting the front or rear axle from the prior art;
• 2 a vehicle with parallel lifting of the front and rear axles with a mass flow divider according to the invention;
• 3 an air dryer with air dryer chambers connected in parallel and an upstream mass flow divider;
• 4th a schematic diagram of an embodiment of a mass flow divider according to the invention;
• 5 a first embodiment of a mass flow divider according to the invention with a self-regulating throttle valve;
• 6th a further embodiment of a mass flow divider according to the invention with a throttle combination.

In the figures, the same or similar components are numbered with the same reference symbols.

1 shows in a two-part view a vehicle lifting the front axle 40 (below) or rear axle 44 (above) from the prior art. The arrows on the front axle 40 or on the rear axle 44 symbolize that, according to the prior art, lifting must take place one after the other, since the axes have different pressure levels. As a result, the vehicle is tilted out of the zero position, creating a so-called "ship rocking effect" that can be perceived as uncomfortable by the vehicle's occupants. It is therefore important to avoid this, which is the case with a pneumatic mass flow divider according to the invention 10 and the method according to the invention can be achieved.

In the representation after 2 are the front axle 40 and rear axle 44 with another component 38 connected as a sink to an air supply, to which a pneumatic mass flow divider 10 (not shown) can be connected. The front axle 40 or the rear axle 44 are in the case shown as air suspension 42 educated. In principle, there are also other components 38 conceivable as compressed air actuators.

A problematic mass flow divider according to the invention 10 can be used as an airflow distributor in a vehicle. The vehicle can be powered by a compressor 50 be raised or lowered in parallel, ie without tilting from the zero position. This is in 2 shown. The vehicle can with the mass flow divider according to the invention 10 parallel when being lifted on the front and rear axles. In this way, a “ship rocking effect” can be avoided, which increases the comfort for the occupants.

In the 3 is another application of a mass flow divider according to the invention for an air dryer 52 shown schematically. The air dryer 52 comprises two or more separate drying chambers 54 running in parallel from compressed air from a compressor 50 can be flowed through. This is done at the outlet of the compressor 50 a mass flow divider 10 downstream, which divides the mass flow into two or more parallel mass flows. These can be carried out separately and in parallel through drying chambers 54 to increase the efficiency of air drying. The drying chambers 54 are thus immediately stressed and flooded, so that a higher drying capacity can be achieved. These mass flows can then be via a compressed air busbar 56 merged and attached to a component 38 as a compressed air sink or compressed air actuator, as on the left side of the 3 shown, or for various components 38 which can be operated with different compressed air levels, as shown on the right-hand side of the 3 represented, guided.

In 4th is a principle representation of an embodiment of a mass flow divider according to the invention 10 shown. This has an inlet 12th as well as two processes 16 , 18th on. Between the inflow 12th and the two processes 16 , 18th can, for example, be used as a control element 26th a throttle combination 30th , as in 6th shown, be arranged. For example, one throttle can be used in each case 60 in every process 16 , 18th be arranged. In addition or as an alternative, you can also choose between each sequence 16 , 18th and the inflow 12th at least one 2-way throttle valve 28 can be arranged as a control element 26th is trained. A mass flow 24 from the inflow 12th is consequently in the two processes 16 , 18th equally distributed or unevenly distributed. When the throttle combination 30th with the two throttle 60 is connected in parallel, and this is preferably operated in the supercritical range, the mass flow 24 going through the throttle 60 flows, only from the pressure in the inlet 12th be dependent. The pressures in the drains 16 , 18th can vary without affecting the mass flow 24 changes. This is made possible by the fact that there is a pressure difference between the inlet 12th and the two processes 16 , 18th exists and thus a form in the form of an overprint 48 is trained. In the illustration on the right at the end of the processes 16 , 18th can add more components 38 (not shown) are arranged with the processes 16 , 18th are connected. These other components 38 can have different pressure levels. By means of the pressure differences and the cross-sections of the throttles 60 to one another, the mass flow can be divided in the desired manner.

5 shows a first embodiment of a mass flow divider according to the invention 10 . In this embodiment the control element is 26th as a sliding piston 32 as a self-adjusting throttle valve 28 educated. The piston 32 is orthogonal between and with respect to the inlet 12th and the two processes 16 , 18th arranged. Here is the piston 32 also orthogonal to a direction of flow of the mass flow 24 arranged. Means two return springs 34 becomes the piston 32 in a starting position 36 held so that, depending on the mass flow, self-regulating in a proportional behavior as a throttle valve 28 each of the two processes 16 , 18th can close or open. The feathers 34 are on the ends 35 of the piston 32 arranged. Due to the spring mounting, the piston can move 32 move horizontally back and forth in relation to the representation. In the starting position shown 36 is the piston 32 in a central position at which the two opening cross-sections 20th , 22nd of the processes 16 , 18th are open by about 50%. The open area of the two processes 16 , 18th is marked with position 2. This forms on the back of the piston 32 Pressure pad 46 in the inlet direction 12th out. These pressure pads 46 result from an overpressure as a pre-pressure in the inlet 12th and a resulting pressure difference between the inlet 12th and the two processes 16 , 18th . Due to different pressure pads 46 in the area of the piston 32 can the piston 32 move, whereby the opening cross-sections 20th , 22nd change accordingly in the direction in which the piston 32 is deflected. The changes are in the cross-section of the opening 20th , 22nd interdependent, since both by one and the same piston 32 to be triggered. If now from a first sequence 16 , more air flows out, this becomes the pressure cushion 46 lower in this area. As a result, the piston moves 32 in this direction and reduces the opening cross-section 20th . This increases the mass flow 24 reduced again in this area and instead on the opposite side, ie on the other drain 18th , elevated. Ideally, the piston can 32 self-leveling in such a way that on both sides, ie on both processes 16 , 18th , flows through the same mass. To this extent, this embodiment represents a proportionally working and self-regulating throttle valve 28 represent.

In 6th is a further embodiment of a mass flow divider according to the invention 10 shown. This has an inlet 12th as well as two processes 16 , 18th on. Incoming 12th is, for example, a controllable air compressor 50 provided the compressed air from an atmospheric air inlet 58 provides. Between the inflow 12th and the two processes 16 , 18th is as a rule element 26th a throttle combination 30th with two chokes 60 arranged. For example, one throttle in each case 60 in every process 16 , 18th be arranged. Furthermore, alternatively or additionally between the processes 16 , 18th and the inlet at least one throttle valve 28 be arranged as a rule element 26th is trained. A mass flow 24 from the inflow 12th is consequently in the two processes 16 , 18th equally distributed or unevenly distributed. When the throttle combination 30th with the two throttle 60 is connected in parallel, and this is preferably operated in the supercritical range, the mass flow 24 going through the throttle 60 flows, only from the pressure in the inlet 12th be dependent. The pressures in the drains 16 , 18th can vary without affecting the mass flow 24 changes. This is made possible by the fact that there is a pressure difference between the inlet 12th and the two processes 16 , 18th exists and thus a form in the form of an overprint 48 is trained. In the illustration, at the right end of the processes 16 , 18th further components 38 (not shown) are arranged with the processes 16 , 18th are connected. These other components 38 can be air pressure actuators or other sinks for compressed air and can have different pressure levels.

List of reference symbols

10

pneumatic mass flow divider

12th

Intake

14th

Opening cross-section of the inlet

16

procedure

18th

procedure

20th

Opening cross-section of the drain

22nd

Opening cross-section of the drain

24

Mass flow

25a

Partial mass flow

25b

Partial mass flow

26th

Control element

28

Throttle valve

30th

Throttle combination

32

piston

34

Return spring

35

End of the piston

36

Starting position

38

Component

40

Front axle

42

Air suspension

44

Rear axle

46

Pressure pad

48

Overpressure

50

compressor

52

Air dryer

54

Drying chamber

56

Compressed air busbar

58

Atmospheric air intake

60

throttle

100

Vehicle with air suspension

Claims (16)

Pneumatic mass flow divider (10) for pneumatic air suspension of a vehicle (100) with an inlet (12) with an opening cross-section (14), at least two outlets (16, 18) each having an opening cross-section (20, 22) being included, one Mass flow (24) which can be introduced into the inlet (12), into which at least two outlets (16, 18) can be distributed uniformly or adjustably unevenly distributed as partial mass flows (25a, 25b), a maximum of the pressures of the partial mass flows (25a, 25b) ) is lower than a pressure of the mass flow (24) in the inlet, characterized in that the inlet (12) is connected to the two outlets (16, 18) via a control element (26). Pneumatic mass flow divider (10) according to Claim 1 , characterized in that the control element (26) is at least one throttle valve (28). Pneumatic mass flow divider (10) according to Claim 1 or 2 , characterized in that the control element (26) is at least one throttle (60), in particular a throttle combination (30). Pneumatic mass flow divider (10) according to one of the Claims 1 to 3 , characterized in that the regulating element (26) is designed as a displaceable piston (32) of a self-regulating distributor valve (28), the two opening cross-sections (20, 22) of the outlets (16, 18) each being displaced by the piston (32) are at least partially, in particular antiparallel, proportionally openable or closable. Pneumatic mass flow divider (10) according to Claim 4 , characterized in that the piston (32) has at least one return spring (34), in particular two return springs (34) at each end (35) of the piston (32), the piston (32) being supported by the at least one return spring ( 34) is resettable, in particular self-resettable, into a neutral starting position (36). Pneumatic mass flow divider (10) according to Claim 4 or 5 , characterized in that the piston (32) is arranged orthogonally between and with respect to the inlet (12) and the two outlets (16, 18), in particular is arranged orthogonally with respect to a direction of flow of the mass flow (24). Pneumatic mass flow divider (10) according to one of the preceding claims, characterized in that the two processes (16, 18) are each connected to at least one further component (38), in particular a compressed air actuator or a compressed air sink, the at least two components (38 ) preferably have different pressure levels. Pneumatic mass flow divider (10) according to one of the preceding claims, characterized in that a first outlet (16) with a front axle (40) of an air suspension chassis (42) and a second outlet (18) with a rear axle (44) of the air suspension chassis (42) connected is. Pneumatic mass flow divider (10) according to one of the preceding Claims 1 to 8th , characterized in that a first outlet (16) is connected to an inlet of a drying chamber (56) of an air dryer (52) and a second outlet (18) is connected to an inlet of a second drying chamber (56) of the air dryer (52). Pneumatic mass flow divider (10) according to one of the preceding claims, characterized in that the two opening cross-sections (20, 22) of the outlets (16, 18) have the same cross-sectional area in terms of area. Pneumatic mass flow divider (10) according to one of the preceding claims, characterized in that the opening cross-section (14) of the inlet (12) has a cross-sectional area which, in terms of area, corresponds to a cross-sectional area of a sum of the two opening cross-sections (20, 22) of the outlets (16, 18) equals or is greater. Method for dividing a pneumatic mass flow, wherein a mass flow (24) from an inlet (12) with a cross-sectional area (14) is proportionally divided as partial mass flows (25a, 25b) and divided into two outlets (16, 18) each with a cross-sectional area (20, 22), the two outlets (16, 18) being connected to different pressure levels and an overpressure (48) with respect to a maximum of the pressures of the partial mass flows (25a, 25b) of the outlets (16, 18) being present in the inlet (12) , characterized in that the mass flow between the inlet (12) and the respective outlet (16, 18) can be regulated via a regulating element (26) between the inlet (12) and the outlets (16, 18). Procedure according to Claim 12 , characterized in that the control element (26) is designed as a throttle combination (30) and / or as a displaceable piston (32) of a distributor valve (28), the piston (32) being held in a central position by means of at least one return spring (34) , in which the cross-sectional areas (20, 22) of the outlets (16, 18) are each 50% open. Procedure according to Claim 13 , characterized in that at least two different pressure pads (46) rest on the piston (32), the piston (32) being deflected from the starting position (36) by the different pressure pads (46), whereby the respective opening cross-sections (20, 22 ) of the processes (16, 18) can be changed. Procedure according to Claim 14 , characterized in that the different pressure cushions (46) result from the outflowing partial mass flows (25a, 25b) of the processes (16, 18), the piston (32) being displaced in the direction of the lower pressure cushion (46) by the return spring mounting and the there is a reduced cross-section of the opening of the drain (16, 18). Method according to one of the Claims 13 to 15th , characterized in that the piston (32) levels off in such a way that an equal partial mass flow (25a, 25b) flows through both opening cross-sections (20, 22) of the two outlets (16, 18).

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