WO2016131860A1

WO2016131860A1 - Device for damping pressure fluctuations

Info

Publication number: WO2016131860A1
Application number: PCT/EP2016/053344
Authority: WO
Inventors: Johann Riepl; Michael Schnell; Bernd SEGGEWISS; Stefan Weickmann
Original assignee: Conti Temic Microelectronic Gmbh
Priority date: 2015-02-19
Filing date: 2016-02-17
Publication date: 2016-08-25
Also published as: DE102015203022A1

Abstract

The invention relates to a device (DV) for damping pressure medium fluctuations in a pressure medium (DM). The device has a housing (GH) which encloses a damping volume (DVO). The device further has a partition (TW) for dividing the damping volume into a suction channel (ASK) and a pressure channel (DKK ). The suction channel is divided into a first suction chamber (AK1) and a first expansion chamber (EK1) by a first expansion element (EE1) such that pressure fluctuations in the pressure medium are damped when the pressure medium is flowing from the first suction chamber into the first expansion chamber through the first expansion element. For the same purpose, a second expansion element (EE2) is provided in the pressure channel, said second expansion element dividing the pressure channel into a second suction chamber (AK2) and a second expansion chamber (EK2). In particular, a pressure medium filter is integrated in the first suction chamber such that the device is not only used as a damper but also as a pressure medium filter.

Description

description

The present invention relates to a device for damping pressure fluctuations occurring in a pressure medium, in particular for a pressure medium pump. Furthermore, the invention relates to a pressure medium pump, in particular for a pneu ^¬ matic adjustment of a vehicle seat.

In modern vehicle seats can be filled with a pressure medium, in particular with compressed air bubbles as adjusting elements in a region of the seat or seat back (together referred to as seating surface) and can be supplied via a respective pressure medium line with pressure medium. By filling a respective bladder with pressure medium whose volume is increased, thereby the properties of a seat back or seat in the contour can be changed. In addition to a static adjustment of the contour of the seat back or seat, for example in the context of a Lordosestütze, this massage and massage functions for a passenger in the vehicle seat are possible by a regular or dynamic change in the contour of the seat back or seat. For filling a bubble with pressure medium, this is first generated by a pressure medium source, such as a compressor, and passed through a corresponding valve, in particular an electropneumatic valve in a control unit to a respective bladder. Such pneumatic arrangements, such as a just mentioned pneumatic adjustment arrangement for a vehicle seat are installed as comfort functions in the passenger compartment. It is important that the noise level in the passenger compartment is so low that the noise of the just mentioned components, such as the pneumatic adjustment in their operation by the passengers or the driver are not bothersome. As already mentioned, a compressor, such as a vane cell compressor, is used for the pressure medium generation in an adjustment arrangement for the vehicle seat. Such a compressor generates due to the design of the pressurized pressure medium with pulsations or Druckschwan ^¬ effects. This usually results in noise emissions that are unacceptable to passengers in the passenger compartment.

Thus, the object of the present invention is to reduce the noise generated by pressure fluctuations, especially in a pneumatic adjustment arrangement.

This object is achieved by the subject matter of the independent claims to ^¬. Advantageous embodiments are the subject of the dependent claims.

According to a first aspect of the invention, a device is provided for damping pressure medium fluctuations in a pressure medium. In this case, this device is preferably used in or for a pressure medium pump in order to dampen fluctuations in the pressure medium directly at the place of formation. to prevent . In this case, the device comprises a housing which encloses a damper volume. Further, it has a partition wall for dividing the damper volume in an on ^¬ suction channel and a pressure channel. The two channels are separated by fluid pressure or fluid technology. In this case, a first expansion element is arranged in the intake channel, which subdivides the intake channel into a first intake chamber and a first expansion chamber, so that pressure fluctuations or pulsations in the pressure medium are damped when flowing from the first intake chamber through the first expansion element into the first expansion chamber. Furthermore, in the Pressure passage, a second expansion element is provided, which divides the pressure channel into a second Ansaugkammer- and into a second expansion chamber, so that pressure fluctuations in the pressure medium are attenuated when flowing from the second suction chamber through the second expansion element in the second expansion chamber. In this way, with minimized vor ^¬ directional effort in a single component for both a suction side, as well as for a pressure side, ie in two flow directions, a damping of pressure fluctuations provided in the ^¬ generation of the pressure medium, in particular by a pressure medium pump, or a compressor arise. Above all, the device serves to dampen pressure fluctuations, in particular for direct connection to a pressure medium pump, so that the pressure fluctuations or pulsations are attenuated or prevented on the one hand directly at the place of formation, so as a possible gain or increase the pulsations of the device for damping prevent pressure fluctuations subsequent components of a pneumatic arrangement. Furthermore, the installation space can be minimized by damping the pressure fluctuations for two flow directions (during suction and pressure delivery) of the pressure medium in a single device.

According to an embodiment of the apparatus, the housing has a first end portion in which the first suction chamber and the second expansion chamber are disposed, and has a second end portion in which the first pressure chamber and the second suction chamber are arranged. In this way, two pressure fluid flows in the intake and in

Pressure channel aligned in the opposite direction. This allows in particular a slight connection of the device with the pressure medium pump or its inlet and outlet for pressure medium. According to a further embodiment of the device, the first suction chamber and the second expansion chamber are closed by a common end plate at the first end portion. In this way, further components can be reduced and also the device complexity can be minimized. It is also conceivable that in the second section, the second suction chamber and the first expansion chamber are closed by a common end plate. According to a further embodiment, an above-mentioned end plate has at least one through-passage or one

Through hole, can flow through the pressure medium from the outside into the first suction chamber and / or pressure medium from the second expansion chamber to the outside. Of course, it is conceivable that a respective pressure medium inlet can be arranged in the first suction chamber and a different location of the housing of the device, just as it is conceivable that a corresponding outlet from the second expansion chamber may be provided at a different location of the housing of the device ,

According to a further embodiment, the device comprises a first filter element for filtering out particles from the pressure medium, wherein the filter element is preferably provided in the first suction chamber. In this way it is ensured that particles which otherwise merely lead to clogging of the pressure medium lines of a pneumatic arrangement or of the pressure medium pump are filtered off at the very beginning of the intake (when entering a pneumatic arrangement). It is particularly advantageous if the first filter element is held between the first expansion element and the end plate at the first end section.

Particularly advantageous is an embodiment in which the end plate is detachably fixable to the housing of the device, while _n

For example, by means of screws, so that the first filter element (or other filter elements) can be used after removing the end plate in a simple way in the suction or, if necessary, can be easily replaced again.

In this context, it is also advantageous to provide next to the first filter element another filter element for ^¬ filtering out particles from the pressure medium, in particular the first filter element as a coarse filter for pre-filtering the compressed air and downstream of the pressure medium ^¬ flow then the second filter element as a Fine filter is provided for filtering out smaller particles. In this context, the first filter element may contain foam, while the second filter element may comprise a filter paper. Both filter elements are preferably arranged in flow direction ^¬ after another in the first suction chamber and held between the end plate and the first expansion ^¬ element of the housing in the first end portion.

According to a further embodiment, the outer contours of the first and / or the second filter element cooperate in a form-fitting manner with the inner contours of the first suction chamber, so as to prevent a movement or deformation of the filter element or elements. In this case, the first suction chamber or the enclosing part of the housing in the inner contour and the corresponding outer contour of the filter or the filter elements are constructed unsym ^¬ metric, so that in particular a moving or twisting is not possible.

According to a further embodiment, a connection for connecting the first expansion chamber to the inlet of a pressure medium pump is provided (in particular at the second end section of the device) and is a further connection to the Connecting the second suction chamber with the outlet (pressure medium outlet) of the pressure medium pump provided. In this way the device for damping pressure fluctuations can be easily connected to the pressure medium pump, can be placed on it on ^¬, or be fixed in a similar manner.

According to a further embodiment of the device, the first and / or the second expansion element is designed such that it has one or more diffuser elements. The diffuser element or elements are arranged in the device so as to act from the respective suction chamber toward the expansion chamber, i. that a pressure medium flow coming from the suction chamber expands forth and is thus reduced in speed in the direction of the respective expansion chamber, so as to dampen the pressure fluctuations or pulsations.

In this connection, it is conceivable for the first and / or the second expansion element to have one or more through-holes each having a widening diameter as diffuser elements, an expansion element formed in this way being aligned in the device such that the one or more through-holes expand in diameter from a respective suction chamber to a corresponding expansion chamber. For this purpose, the first and / or second expansion element preferably has a plate in which the through holes are provided. In this way, there is provided a method and apparatus with little technical effort to formative expansion element which can be arranged in a per ^¬ weiligen suction chamber port or pressure port.

According to a further embodiment of the device, the housing has a hollow cylindrical body (in the interior of the damper volume is provided). Especially the partition then runs parallel to the cylinder axis of the hollow cylindrical body. Furthermore, it is conceivable that the first and the second expansion element is then aligned perpendicular to the cylinder axis. Due to the design of the housing with a hollow cylindrical body, on the one hand, a space-saving construction of the device can be created and, moreover, the shape of the hollow cylinder can be adjusted, for example, according to the shape of the Druckmit ^¬ tel pump to be connected or their connections, so on the one hand an attractive appearance and moreover to achieve a ^space- saving design of the entire pressure medium source.

In this context, it is also conceivable to form the main body including the partition wall and the two expansion elements in one piece, in particular in the form of a

(Injection) casting. In this case, the base body made of plastic or a light metal, such as aluminum can be produced. In this way, a production with low procedural ^¬ technical effort is possible.

According to a further aspect of the invention, a pressure medium pump, in particular for a pneumatic arrangement, such as a pneumatic adjustment arrangement for a vehicle seat, having the following features is provided. It has an inlet for drawing in pressure medium, such as air. Further, it has an outlet for discharging pressurized

Pressure medium. Finally, it comprises a device for damping pressure fluctuations as described above or an embodiment thereof, wherein the first expansion chamber of the device with the inlet of the device and the second

Suction chamber of the device is connected to the outlet of the device. Since the second suction chamber is connected in cooperation with the outlet of the pressure medium pump, it can also be referred to as a pressure chamber in such a case. In general, the terms intake port and pressure channel indicate that, especially when used with a pressure medium pump, the intake port of the device for damping pressure fluid fluctuations with the inlet of the pressure medium pump for the suction of pressure medium, and the

Pressure channel of the device is connected to the outlet of the pressure medium pump for outputting pressurized pressure medium. In the following, exemplary embodiments of the present invention will now be explained in more detail with reference to the accompanying drawings.

Show it:

Figure 1 is a schematic sectional view of a device for damping pressure fluctuations in a pressure medium according to a first embodiment; Figure 2 is a schematic detail view of an expansion ^¬ elements of the device of Figure 1; a schematic representation of a pneumatic adjusting arrangement with a device for damping pressure fluctuations;

Figure 4 is a schematic representation of an apparatus for

Damping of pressure fluctuations according to a second embodiment of obliquely right front, which is connected to a pressure medium pump;

Figure 5 is a schematic front view of the device for

Damping of pressure fluctuations of Figure 4 with the end plate removed; Figure 6 is a schematic exploded view of the device for damping pressure fluctuations of Figure 4, in which in particular also filter elements for filtering out particles from the pressure medium can be seen.

Reference is first made to Figure 1, in which a device DV for damping pressure fluctuations in a pressure medium DM, in particular in the form of air, is shown. As can also be seen in Figure 1, the device DV is particularly adapted to be directly connected to a pressure medium pump FZP (see Figure 3) to pressure fluid fluctuations that occur especially during operation of the pressure medium pump, at the location of Ent ^¬ to dampen or prevent it from occurring.

The device DV comprises a housing GH enclosing a damper volume DVO. This damper volume is divided by a partition wall TW into an intake passage ASK and a pressure passage DKK. The two channels pressure medium ^¬ technically or fluidly separated from each other. If the lower part of the device DV, ie the intake duct ASK, is considered, a first expansion element EE1 is arranged therein, which subdivides the intake duct ASK into a first intake chamber AK1 and a first expansion chamber EK1. Considering the upper part of the device DV, ie the pressure channel DKK, a second expansion element EE2 is arranged therein, which divides the pressure channel DKK into a second suction chamber AK2 and a second expansion chamber EK2. In this case, the first suction chamber AK1 and the second expansion chamber EK2 are covered or closed by a common end plate AD. However, this end plate has an inlet opening DE for admitting pressure medium into the first suction chamber AK1. As will be explained later on, the arrangement of the first expansion element EE1 causes the velocity of a pressure medium DM flowing in the suction chamber ASK (in the lower left of the device DV) to flow through the first expansion element EE1 due to the diffuser provided therein. reduced sorelemente. This expansion of the pressure medium DM through the diffuser elements (illustrated by a divergence of the pressure medium flow arrows) of the first Ex ^¬ expansion element EE1 (see also Figure 2) causes not only a reduction in the speed of the pressure fluid flow, but also a reduction of pressure fluctuations or pulsations in the pressure medium. The expanded in the first expansion chamber EK1 pressure fluid then flows via a corresponding pump-side outlet port DFA into a pressure medium inlet FE of the pressure medium pump, is compressed there and is pressurized and out of the pressure medium pump FZP blank at a pressure central outlet FA again ^¬. The pressure medium pump may be, for example, a compressor, such as a vane compressor.

Now, the pressurized pressure medium DM flows via a pump-side pressure medium inlet DFE into the second suction chamber AK2. Due to the operation of the pressure with ^¬ telpumpe FZP are in the pressure medium pressure fluctuations fact, the choice now to be damped by means of a second expansion member EE2 or prevented. The operation of the second expansion element EE2 is the same as that of the first expansion element. Here, in this second Ex ^¬ pansionselement EE2 turn diffuser elements, through which the flowing pressure fluid is expanded DM what has been illustrated by the widening pressure fluid flow arrows in the figure. The expansion of the pressure medium again leads to a reduction of the flow velocity and thus to a reduction of the pressure medium. Fluctuations or pulsations in the pressure medium. The damped in the second expansion chamber with respect to the pressure fluctuations pressure medium DM is now discharged via a Druckmittelauslassöffnung DA from the device DV and the second expansion chamber and, for example, fed to a pneumatic adjusting device, as shown in Figure 3.

If one now considers the housing GH in detail, this has a main body GK, which has a hollow cylindrical shape. In this case, the partition wall is arranged in this hollow cylinder such that it runs parallel to a cylinder axis ZA. Furthermore, it can be seen that the respective expansion elements EE1 and EE2 are aligned such that they are perpendicular to the cylinder axis ZA. However, another arrangement of the expansion elements EE1 and EE2 is conceivable, for example, at an angle to the cylinder axis ZA.

Considering the filter housing further, this has a left or first end portion ABL, in or on which the first suction chamber AK1 and the second expansion chamber EK2 are arranged. Further, the device has a right or second end portion AB2, on or in which the first expansion chamber EK1 and the second suction chamber AK2 are arranged. Due to this design of the device DV, the intake flow through the intake passage ASK runs in the opposite direction to the pressure medium flow in the pressure channel DKK. The construction has the advantage that the device DV, as already mentioned above, thus on the one hand has a small space, and on the other hand is so easily adapted that they to a pressure medium inlet FE and a pressure medium outlet FA to a contact portion of the pressure medium pump FZP to simple Way is attachable.

The housing GH, including the main body GK, and the partition and the two expansion elements are advantageous legally integrally formed, and may be made of plastic or aluminum. In this way, a production with little procedural effort is possible. Reference is now made to Figure 2, in which a schematic

Detail view of the expansion element EE1 or EE2 is shown. This comprises a plate PL, in which one or through-holes are provided as diffuser elements DL. Viewed from left to right, the through holes widen from a first diameter D 1 to a larger diameter D 2 (DKD 2), so that the speed increases due to these diameter or cross-sectional enlargements for a pressure medium flowing from the left (suction chamber) to the right (expansion chamber) of the pressure medium and thus pressure fluctuations or pulsations in the pressure medium can be reduced.

Reference is now made to Figure 3, in which a schematic representation of a pneumatic adjustment PVA is shown. As a pressure medium source, this pneumatic displacement arrangement PVA comprises a pressure medium pump FZP (for example in the form of a vane pump), which is connected to a device for damping pressure fluctuations. In this case, the device DV can be designed in accordance with the device DV according to FIG. Of course, it is also conceivable that the device for damping pressure fluctuations according to the embodiments in Figures 4 to 6 is formed.

As can be seen in Figure 3 bottom left, pressure medium DM flows through an inlet opening DE of the device DV into the corresponding intake duct ASK (see also Figure 1), is attenuated with respect to any existing pressure fluctuations in order to effect a noise reduction, and then flows into the pressure medium pump FZP. There it is compressed by a Ver ^¬ density unit VDE or pressurized and then flows into the pressure channel DKK of the device DV, there again to dampen the pressure fluctuations or pulsations in the pressure medium due to the operation of the pump FZP. The "damped" pressure means DM then flows via the outlet ^¬ opening DA in a pressure medium supply line DML to a valve (in particular an electro-pneumatic valve EPV), which is electrically controlled by a control unit STE. The pressure medium flow can be controlled by the pressure medium supply line DML such be that the pressure medium is either blocked at the valve EPV or that it is passed to the pressure medium line DL1 or DL2 .. The pneumatic adjusting arrangement PVA further comprises a first bladder Bl and a second bladder B2, via the respective pressure medium lines DL1 and DL2 with the In other words, when the electropneumatic valve EPV is opened, the pressurized pressure medium DM flows into the bubbles B1 and B2, respectively, so that the volume of the bubbles is increased by the pressure medium when used as adjusting elements in a region of the seat surface or seat back of a vehicle seat FZS are arranged, which change the corresponding contour of the seat back or seat surface. In this way, static functions, such as a lumbar support can be achieved by means of the bladder Bl or B2, or even regular or dynamic functions such as massage functions as comfort application.

In any case, are reduced by the device DV as a damper, in particular by the operation of the pump FZP resulting pressure fluctuations and thus corresponding No ^¬ ions ^¬ sions, namely to an acceptable level for the passenger or the driver. Reference is now made to Figure 4, in which a device for damping pressure fluctuations in a pressure medium according to a second embodiment of the invention is shown in a view obliquely from the front and side. In this case, the device DV1 in terms of construction with respect to the channels and chambers as well as the expansion elements substantially corresponds to the device DV in Figure 1, wherein the main difference with respect to Figure 5 will be explained in more detail.

As can be seen in FIG. 4, the device DV1 is directly connected in its second end section AB2 or right end section shown in the figure to a pressure medium pump FZP, for example a vane compressor. This is done in a corresponding manner, as shown in Figure 1, which is why reference is made to the description of Figure 1 for a more detailed explanation. It can be seen on the left end section AB1 of the device DV1 in the figure that an end plate AD is provided on the main body GK of the housing GH, which is fastened to the main body by means of screws S. In the end plate AD, an inlet port DE is provided through which pressure medium DM flows into the device DV1, more specifically into the first suction chamber AK1 corresponding to the structure of FIG.

Reference is now made to FIG. 5, in which the device shown in FIG. 4 for damping pressure fluctuations with the end plate AD removed is shown. It can be seen that six threaded recesses or holes SL are provided in the main body GK, which can cooperate with the screws S of Figure 4, to attach the end plate AD on the base body by screwing the screws S. In the lower part of FIG. 5, a pressure medium outlet DA is shown, through which pressurized pressure medium DM flow to a special pneumatic connection, such as, for example, to the valves or bubbles of a pneumatic adjustment arrangement for a vehicle seat can. This outflowing pressure medium DM comes from the second expansion chamber EK2, after it has flowed through the second expansion element EE2, possibly contained pressure ^fluid fluctuations ^¬ or pulsations have been damped. In the inner circumference of the main body GK, a sealing element ABD is shown, which is intended to lead in contact with the end plate AD to a fluid-tight space or to a fluid-tight second expansion chamber EK2 or a fluid-tight suction chamber adjacent thereto. The essential difference between the device DV1 and the device DV is that a (first) pressure medium filter LF1 is provided in the first suction chamber (AK1). This serves to remove located in a sucked pressure medium particles P, so as to prevent clogging located in an associated pneumatic system, or in an associated pneumatic arrangement pressure medium lines.

But it is possible that only a single Druckmit- telfilter or a pressure medium filter is provided with a single filter material in the suction chamber. With reference to FIG. 6, in which an exploded view of the device DV1 shown in FIG. 4 is shown, it can also be seen that a second or further pressure medium filter LF2 is provided in addition to the first pressure medium filter LF1. Here, the first pressure medium filter LFl can be designed as a coarse filter material with a foam material, while the second filter LF2 also can be used from small particles as a fine filter for example with a Filterpa ^¬ pierelement for filtering. As can be seen in FIG. 6, the respective outer contours of the filter elements LF1 and LF2 are adapted to the inner contours of the first suction chamber AK1, so that a positive connection is created which prevents a movement (twisting) of the filter elements and thus a reduced filter property. The in the Figures 4 to 6 shown device DVL has advantageously used the space of the first suction chamber as an additional function to provide one or more filter elements therein. In particular, these filter elements are then held between the end plate AD and the first expansion element EEL (as well as the partition wall and the base body. In this way, the device DVL respect not only fulfills a damping ^¬ property pressure medium fluctuation or Druckmittelpulsation, but also a filter, without the Such a dimensionally minimized pulsation damper with integrated pressure medium filter is thus well suited for use in a motor vehicle since there is generally little space for additional components in the vehicle interior.

Disclosed is thus a device for damping pressure fluctuations in a pressure medium, in particular air, with a housing in which an intake passage is provided. In this, an expansion element is arranged, which divides the intake passage into a first suction chamber and an expansion chamber, so that pressure fluctuations in the pressure medium are attenuated when flowing from the suction chamber through the first expansion element in the first expansion chamber. Furthermore, a filter element for filtering out particles from the pressure medium in the suction chamber is provided. In this way, the Druckmit ^¬ telfilter is integrated into the device, without increasing the Ab ^¬ measurements of the device.

Claims

claims

1. Device (DV, DV1) for damping pressure fluctuations in a pressure medium (DM), having the following features:

a housing (GH, GK) enclosing a damper volume (DVO);

- A partition (TW) for dividing the damper volume (DVO) in an intake passage (ASK) and a pressure channel (DKK);

- Wherein in the intake passage (ASK), a first expansion element (EE1) is arranged, which divides the intake passage (ASK) into a first suction chamber (AKl) and a first expansion chamber (EK1), so that pressure fluctuations in the pressure medium (DM) when flowing through are attenuated from the first suction chamber (AK1) through the first expansion element (EE1) into the first expansion chamber (EK1), and

- In which in the pressure channel (DKK) a second expansion element (EE2) is arranged, which divides the pressure channel (DKK) into a second suction chamber (AK2) and a second expansion chamber (EK2), so that pressure fluctuations in the pressure medium (DM) when flowing through from the second suction chamber (AK2) are attenuated by the second expansion element (EE2) in the second expansion chamber (EK2).

2. Device according to claim 1, wherein the housing (GH) has a first end portion (ABl), on which the first suction chamber (AKl) and the second expansion chamber (EK2) are arranged, and a second end portion (AB2), at the second expansion chamber (EK1) and the second suction chamber (AKl) are arranged.

3. Apparatus according to claim 2, wherein at the first end portion (ABL), the first suction chamber (AK1) and the second expansion ^¬ onskammer (EK2) of a common end plate (AD) are completed.

4. Apparatus according to claim 3, wherein the end plate (AD) has at least one through hole (DE), by the pressure medium in the first suction chamber (AK1) and / or from the

Pressure medium from the second expansion chamber (EK2) can flow.

5. Device according to one of claims 1 to 4, further comprising a first filter element (LF1) for filtering out particles (P) from the pressure medium (DM), wherein the first filter element (LF1) in the first suction chamber (AK1) is provided ,

6. Apparatus according to claim 5, further comprising a second filter element (LF2) for filtering out particles from the pressure medium, wherein in particular the first filter element is provided as a coarse filter for pre-filtering and the second filter element as a fine filter.

7. Apparatus according to claim 5 or 6, wherein the outer contours of the first and / or the second filter element interact positively with the inner contours of the first suction chamber (AK1).

8. Device according to one of claims 7, wherein the first expansion chamber (EK1) has a connection (DFA) for connection to the inlet (FE) of a pressure medium pump (FZP) and the second suction chamber (AK2) has a connection (DFE) for connection to having the outlet (FA) of the pressure medium pump.

9. Device according to one of claims 1 to 8, wherein the housing (GH) has a hollow cylindrical body (GK) in which the partition wall (TW) extends parallel to the cylinder axis (ZA).

10. Device according to one of claims 1 to 9, wherein the first and / or the second expansion element comprises one or more difusorelemente.

11. The apparatus of claim 10, wherein the first and / or the second expansion member (EE1, EE2) one or more through ^¬ holes (DL) to be expanded diameter (Dl; D2) than the diffuser elements, wherein a respective Expan ^¬ sion element (EE1, EE2) in such a manner in the device (DV, DV1) is aligned such that the one or more through ^¬ holes (DL) in diameter from a respective suction chamber (AKL, AK2) (to an opponent expansion chamber EK1, EK2) expand.

12. Pressure medium pump (FZP) in particular for a pneumatic arrangement (PVA) with the following features:

an inlet (FE) for sucking pressure medium (DM);

an outlet (FA) for discharging pressurized fluid

Pressure medium (DM);

a device for damping pressure fluctuations according to one of claims 1 to 11, wherein the first expansion chamber of the device (DV, DV1) with the inlet (FE) and the second suction chamber (AK2) of the device (DV, DV1) with the outlet (FA ) connected is.