WO2018184722A1 - Filter assembly for a fluid - Google Patents

Abstract

The invention relates to a filter assembly (10, 110) for a fluid (174), having a filter housing (12, 112). Said filter housing (12, 112) has an inlet opening (18, 118) for an inlet channel (20, 120) and an outlet opening (36, 122) for an outlet channel (34, 124). A through-flow element (24, 132) is located in the filter housing (12, 112). Said through-flow element (24, 132) has a filter support wall (28, 138), thereby forming a hollow body (26, 134) having an interior space (22, 136) and an exterior space (32). The interior space (22, 136) is coupled to the inlet channel (20, 120) and the exterior space (32) is coupled to the outlet channel (34, 124). The filter support wall (28, 138) has openings (29) through which the fluid (174) is conducted for filtering. A movable cleaning plunger (38, 150) is provided for removing deposits from the filter support wall (28, 138).

Description

 Filter arrangement for a fluid

 Technical area

The invention relates to a filter arrangement for a fluid with a filter housing, wherein a) the filter housing contains an inlet opening for an inlet channel and an outlet opening for an outlet channel,

b) a flow body is provided in the filter housing,

c) the flow body has a filter support wall, whereby a hollow body is formed with an interior space and an exterior space,

d) the interior is coupled to the inlet channel and the exterior is coupled to the outlet channel,

e) in the filter support wall openings are provided through which the fluid is passed for filtering,

f) a slidable cleaning punch is provided which removes deposits on the filter support wall.

Furthermore, the invention relates to a filter arrangement for a fluid according to the preamble of independent patent claim 18.

description

Such filter arrangements are used in plastics processing. In plastics processing plants, a plastic granulate, regrind or powdered ingredients is often heated to liquid plastic to process it. The plastic granulate is often made of recycled material, which often contains impurities by foreign particles. For example, extruders are used as plastics processing plants. Extruders are conveying devices which, in accordance with the principle of the screw conveyor, uniformly press solid to viscous masses out of a shaping opening under high pressure and high temperature. Other systems use this e.g. also gear pumps.

The heated and viscous plastic is also mixed with pure particles usually with dirt particles. These dirt particles must be kept out of the plastic processing plants. For this purpose, suitable filters are used, which filter out these dirt particles from the liquid plastic. The liquid plastic is passed under pressure through the filter assembly before the raw material in the plastic processing plant is processed further.

In order to obtain a uniform processing process, as constant a processing pressure as possible is required. In the filter arrangements, the screen filters must be regularly replaced or cleaned. For this purpose, various changing devices are used, the currently used screen changing systems include the Kolbensiebwechsler, the Siebradfilter, the belt screen changer, the rotary screen changer and the flat slide. The screen changing systems usually operate automatically, i. mechanically or hydraulically driven. However, there are also manual Siebwechselsysteme in use.

State of the art

DE 20 2010 017 247 U1 describes an apparatus for filtering a fluid, in particular for filtering a thermoplastic polymer melt. The Filtriervorrichtüng has a housing with a fluid supply channel and with a fluid discharge channel. It is further disclosed that the housing is provided with two parallel to each other and spaced holes for axially displaceable and fluid-tight storage, each with a bolt. The housing has a passage opening with a filter. As viewed in the flow direction of the fluid to be filtered, a connecting channel is provided in the housing which connects the passage openings downstream of the filter with a displaceable feed of filtered fluid displaceable axially between a first position and a second position and vice versa. A fluid removal channel for filtered fluid branches off from the storage space, so that in the first position of the displacement piston, in which no filtered fluid is stored in the reservoir, the storage space but is constantly flowed through by filtered fluid. From its second position, the displacement piston is first transferred by a radial rotation into an intermediate position in which filtered fluid is stored in the reservoir. After that, by the axial displacement in the first position in which the stored fluid stored in the reservoir in the at least one fluid discharge channel or after an axial displacement of the associated bolt in a downstream side of the filter into the passage opening then emptying flushing channel emptied.

From DE 10 2006 040 703 Al an arrangement for filtering a fluid, in particular a liquefied plastic with a housing of a screen changer is known. The housing contains a supply channel and a discharge channel. In the flow path of the fluid while a transversely displaceably mounted to the flow direction filter holder and at least one filter element is arranged in a corresponding screen space, which is brought into communication with the supply channel and the discharge channel. The resulting from material removal from the process pressure drop or volume shrinkage is sensitively compensated, by a constant pressure and volume constancy is achieved at the discharge channel.

DE 10 2012 100 641 AI discloses a filtering device for large area filtration of plastic melts. The filtration device comprises a housing with an inlet channel and an outlet channel and a longitudinally displaceable to a housing bore filter support element with at least one filter insert. The filter insert is arranged in a production position in a filter chamber between the inlet channel and the outlet channel of the housing. The filter element has a flow-through base element, from which a fluid flow branches off to a plurality of individual filter elements or in which a plurality of fluid streams from the individual filter elements are combined. The filter insert is arranged on an end face of the filter carrier element. The filter chamber is formed by a housing bore which extends to an orifice on a housing outside and in which the filter insert is to be inserted by displacement of the filter support member. A closure element can be placed on the mouth of the housing bore and / or inserted therein when the filter support element is lowered into the housing bore or subsequently onto it.

In DE 20 2012 005 261 Ul a device for filtering a fluid, in particular for filtering a thermoplastic polymer melt, with a housing having a fluid supply channel, a fluid discharge channel and a bore disposed therein is described. The bore is in fluid communication with the fluid supply channel and the fluid discharge channel, respectively. In the bore a bolt is mounted axially displaceable. The bolt is thereby provided with a filter test with an inflow side and a downstream side, wherein the inflow side of the filter test in fluid communication with the fluid supply channel can be brought. The downstream side of the filter test can be brought into fluid communication with the fluid discharge channel. The bolt is sealed against the housing by means of a form-locking clamped between the bolt and housing ring seal.

DE 20 2013 003 829 U1 also discloses a filter device for filtering fluid with a housing in which a filter holder with a screen cavity is provided. The Siebkavität has a dirty side and a clean side. In the Siebkavität is a filter element which is arranged displaceably in the housing. The housing further has an inlet opening and a drain opening. A feed channel leads from the inlet opening to the dirty side of the screen cavity. A discharge channel leads from the clean side of the Siebkavität to the drain opening. When viewed in a sectional view of the filter device, the inlet opening and the associated feed channel extend in a first direction. The drain opening and the associated discharge channel extend in a direction inclined relative to the first direction and / or offset in a second direction. In this case, the supply channel and the discharge channel extend accordingly in the portafilter. From DE 20 2014 001 675 Ul a device for filtering a plastic melt with a housing is further known, which has an inlet channel and an outlet channel for the plastic melt. The inlet channel is separated from the outlet channel by a filter cavity for receiving a filter pin axially displaceable therein. The filter pin has a filter base body with a filter surface with there through the filter body passing through the filter openings. Through the filter openings, the plastic melt passes through to a Filtrathohlraum in the filter body. The filtrate cavity is in fluid communication with the exit channel. The filter surface of the filter body is covered by a pleated filter. In axially smoothed edge regions of the pleated filter screen clamping elements are provided.

DE 10 2014 009 666 A1 discloses a melt filter arrangement with a melt channel, a backwash channel and a sieve device for filtering melt in the melt channel. The melt channel and the backwashing channel extend through the screening device at different areas of the screening device. The melt filter arrangement further comprises a backwash screw conveyor within the backwash channel. This generates or defines as a continuous conveying element, the flow in the backwash channel.

From DE 10 2013 216 973 AI a melt filter with a sieve insert receiving, rotatable screen disc is known. By means of a drive device for the rotatable screen disk, a strainer insert within the melt filter can be moved into a melt stream in such a way that the strainer insert lies opposite a melt feed opening. A piston is designed for backwashing and / or flooding such that the drive device for. the backwashing and / or flooding simplified. For this purpose, the piston is in operative connection with the drive device. About the drive device is a backwash and / or flooding driven.

DE 20 2013 101 994 U1 discloses a filter arrangement for fluids, in particular plasticized plastics materials, which has a filter receptacle with a filter chamber and a filter held detachably therein. The filter comprises a removable and fixable in the filter chamber filter carrier with a filter element.

EP 1 519 823 B1, EP 1 697 018 B1, WO 2008/031127 A1 and AT 503 788 A4 disclose filter devices for plasticized plastics materials which have a rotationally driven filter with a disk or cylindrical filter element and a device for removing filter residues having a likewise rotationally driven discharge device. DE 44 06 549 AI shows a method and apparatus for cleaning of polymeric plastics, wherein the filter element is formed as a one-piece and sintered hollow cylinder, which is mounted on a screw and loose in a Filter chamber is inserted, with its axial position is secured by shoulders on screwed housing parts.

DE 10 2010 055 167 AI relates to a device for the continuous filtering of material mixtures, in particular for the separation of impurities from plastic melts, with a rotatably arranged in a filter chamber of a housing filter. A scraper lifts off the contaminants retained by the filter. Finally, a discharge device transports the contaminants lifted off the filter by the wiper from the housing. The discharge device contains an im. Housing rotatably arranged discharge shaft, which has a through opening with a displaceably guided in this transversely to the axis of rotation of the discharge shaft piston.

DE 26 29 151 A relates to a filter apparatus and more particularly to a backwash filter apparatus in which most of the filter media is operational and is filtered while the remaining filter media are cleaned or rinsed in place. The filter apparatus includes a housing with an inlet and a drain. Within the housing, a core tube is arranged, the interior of which is sealed to the inlet connected. The core tube has numerous longitudinally extending rows of openings spaced radially from one another and connecting the interior of the core tube to the outside thereof. Numerous filter elements, each having an inlet and an outlet as well as interposed filter means, are provided.

The filter elements are arranged on the core tube so that their inlets are in fluid communication with the openings in the core tube. The filter means may thereby remove the contaminants from the fluid flowing through the filter medium. Two pistons attached to a hollow connecting rod are slidably disposed inside the core tube. Each piston has longitudinally extending fluid passages and radially extending communication channels. The connection channels can provide a flow connection between the inlet of the filter elements and the interior of the connecting rod. A fluid chamber surrounds the filter elements within the housing. The fluid chamber conducts the cleaned fluid or filtrate to the drain. A positioning device brings the piston in position. The filter elements are spaced apart. A means for generating a pressure in the connecting rod is provided. The pressure is less than the pressure in the fluid chamber for filtrate to backwash the filter elements. Means for discharging the contaminated backwashing fluid through the connecting rod without contaminating the filtrate are associated with a positioning device.

The known filter arrangements with a screen change system have the disadvantage that the screens due to the deposits do not have a long service life and therefore change frequently Need to become. This reduces productivity. In addition, there are downtime during filter replacement, which lead to production stoppage. In addition, there are pressure fluctuations, which can lead to problems in the production process of plastic parts. The known systems for changing the filters are constructed relatively complicated or complicated and thus expensive to manufacture. In addition, the known change systems are very user-friendly.

Disclosure of the invention

An object of the invention is therefore to avoid the disadvantages of the prior art and to provide a filter assembly for liquid media, in particular for liquid plastic, with which can achieve a long service life for the filter. The object of the invention is also to increase productivity. Another object of the invention is to provide a filter assembly, in particular for plastic processing equipment, which is simple in construction and can be produced inexpensively.

According to the invention the object is achieved in that in a filter arrangement for a fluid of the type mentioned g) the flow body is provided in a portion of a piston, wherein the piston is slidably formed in the filter housing to a stop in a piston guide, so that the Flow body is guided to change out of the filter housing.

The invention is based on the principle of initially removing the deposits on the filter support wall by means of a cleaning punch in a known manner. The fluid, usually a molten plastic, is passed through an inlet opening of the filter housing into the flow body. The fluid flows through the filter support wall of the flow body to get from the interior of the flow body in the outer space. Particles of a certain diameter will stick to the filter support wall as a deposit. From the outer space, the cleaned fluid finally passes through the outlet opening into a working area. Nevertheless, it comes to the fact that the filtering flow body must be replaced. This process has been relatively tedious and complicated. To shorten and facilitate this process, the flow body is provided in the wall of a piston, which is pushed out to change out of the filter housing. The piston is largely a hollow body with a wall, for example, has a cylindrical shape. In a portion of the piston, the flow body is provided, for example in the wall thereof. As soon as the piston is pushed out of the filter housing to replace the filtering flow body, the wall of the rinsing piston obstructs the inlet to the flow body. A preferred embodiment of the invention is that a second flow body corresponding to the first flow body is arranged in the filter housing in a second piston, wherein the second piston in the filter housing to a stop in a piston guide is slidably formed, so that the second flow body for changing out of the filter housing can be performed. By using at least two flow bodies, the degree of contamination of the filter support wall is reduced by at least half. Replacement is therefore not required so quickly and the running time of the machine can be increased accordingly.

A preferred embodiment of the filter arrangement according to the invention for a fluid with a filter housing is that the pistons are provided for changing the flow body asynchronously displaceable in the piston guides. By this measure, the flow body can be replaced alternately. As a result, the machine, in which such a filter assembly is used to change the flow body must not be turned off. The pistons can be alternately pushed out of the filter housing to change the flow body. While a flow body is in use and takes over the filtering action of the other flow body, the other flow body can be replaced and / or maintained or cleaned. For this purpose, the inlet channel is shut off to the filtering flow body so that the fluid does not get into the machine unfiltered.

A preferred embodiment of the filter arrangement according to the invention consists in that in each case one inlet channel and one outlet channel are provided for each flow body. This measure serves to enable each flow body to be controlled separately for filtering. In this case, an inlet channel and an outlet channel of a flow body can be shut off. This facilitates the implementation of a change or maintenance of a flow body. The tasks or functions of the flow body can be divided completely and separately in this way.

A further advantageous embodiment of the filter arrangement according to the invention is that the cleaning punches are provided asynchronously displaceable. In order not to carry out unnecessary cleaning processes with the cleaning punch, the cleaning punches can be used asynchronously. For example, they are only put into operation if there is an increased contamination of a filter surface. This can be determined, for example, by a pressure drop or increase with a suitable pressure sensor at the appropriate location in the filter housing.

The cleaning punch is in contact with the filter support wall and is pulled or pushed along it. He covers the filter support wall of the Flow body in only small sections, so that the function of the filter itself is not disturbed. The cleaning stamp lifts the deposits, allowing them to be removed from the filter. The cleaning stamp is completely enclosed by the filter support wall. There is thus the possibility that the cleaning punch can be guided over the entire surface in the interior of the flow body. Because the cleaning punch is only passed over the filter support wall in small sections, the filter support wall of the flow body is not completely covered. This leaves enough area in the filter support wall to ensure the filter function of the filter assembly. The cleaning punch preferably has a relatively flat punch disc. The flat punch disc is understood to mean a disc-like body which can be moved in an axial direction to the filter support wall. The systems in which such filter assemblies are installed, can significantly extend the life.

As an advantageous embodiment of the filter arrangement according to the invention for a fluid has been found, when the hollow body is substantially cylindrical. With a rotationally symmetrical hollow body, the punch disc can be created much easier. A seal between the cleaning punch and the cylindrical hollow body can also be realized more easily with a circular punch disc.

An advantageous aspect of the invention now also results from the fact that the cleaning punch has a flushing piston arranged in parallel with the filter support wall and having a channel. Deposits can be removed via the channel of the flushing piston from the interior of the flow body.

A further advantageous embodiment of the filter arrangement according to the invention also results from the fact that a groove is provided on the circumference of the cleaning punch, which channel is connected to the channel of the flushing piston via a spoke channel. Deposits can now be transported away from the channel via the spoke channel and the channel of the flushing piston. If the pressure in the outer space is greater than the pressure in the channel system, which consists of the channel, the spoke channel and the channel of the flushing piston, the deposits are flushed through the channel system. The oppressor takes away the deposits. The suppression occurs only in the area of the cleaning punch at the openings of the filter support wall.

Preferably, the channel system is connected to the external environment of the filter housing. The deposits thus reach the outside during the cleaning process.

A further preferred embodiment of the filter arrangement for a fluid is that a drive mechanism is provided for the cleaning punch, which the Cleaning stamp along the filter support wall leads. The drive may be formed for example by an electric motor which drives a spindle gear. The spindle pushes and pulls the cleaning punch along the filter support wall of the flow body. This is another step to automate the cleaning process. Suitable control technology can be used to define intervals within which the cleaning process is to be carried out. If necessary, the cleaning intervals can also be adapted to the degree of contamination of the fluid. For the more contaminated a fluid is, the more often the flow body or its filter support wall has to be cleaned.

An advantageous embodiment of the filter arrangement according to the invention for a fluid further consists in that the openings are arranged annularly around and in the filter support wall. The openings are provided in ring sections around the filter support wall. This measure has the advantage that always only one ring section is cleaned. Sequential can thus clean ring section for ring section. The remaining ring sections still filter the fluid.

A further preferred embodiment of the filter arrangement according to the invention for a fluid results from the fact that the inlet opening is connected to the interior. The measure serves to ensure that the fluid first reaches the interior of the flow body. From the interior of the flow body, it passes through the filter support wall and finally passes filtered into the outer space. Appropriately, in one embodiment of the invention, the outlet opening is connected to the outside space. Thus, the filtered fluid can be routed out of the filter housing for further processing.

Furthermore, an advantageous embodiment of the filter arrangement according to the invention for a fluid is achieved in that the filter housing has a detachable housing cover, through which the flushing piston is guided. This measure serves to provide a way to replace the flow body can. For example, by wearing or changing the required openings, replacement may be necessary. This is solved by the housing cover. Since the flushing piston is to communicate with the outside environment, the flushing piston is guided through an opening in the housing cover.

A further advantageous embodiment of the filter arrangement according to the invention for a fluid is achieved in that a pressure generator is provided which presses the fluid with pressure into the interior of the flow body for filtering. The pressure for the fluid is generated for example with a gear pump. By means of the pressure, the fluid is pushed through the filter support wall of the flow body for filtering. Particles whose diameter is greater than the diameter of the openings, remain in the interior of the flow body. In a particularly advantageous embodiment of the filter arrangement according to the invention for a fluid, a filter element in the outer space is arranged on the filter support wall of the hollow body. Preferably, for this purpose, a filter screen - for example, metal or metal alloys - used, which can filter out particles from the liquid. The filter element preferably hugs the filter support wall. While the filter support wall already filters out coarse particles from the fluid, even smaller particles can be filtered out with the filter element. Due to the two-stage filter system it is not so easy to production-inhibiting deposits. Because the coarse particles are already removed on the filter support wall with the cleaning punch. By partial backwashing effects in the case of the cleaning die with gutter deposits on both the filter element and the filter support wall can be removed. The backwashing effects are achieved by pressure differences between the outer space and the channel, which communicates, for example, with the outside environment of the filter housing.

In order to give the filter element sufficient support on the filter support wall, in a preferred embodiment of the invention, the filter element between the hollow body and a hollow body surrounding the perforated plate is arranged. The perforated plate ensures in particular that the filter element does not shift or deform at high heat or high pressure. Through the perforated plate results for the filter element a sufficient dimensional stability.

Alternatively or in combination may be arranged in the interior of the hollow body in an embodiment of the filter assembly according to the invention, a filter element. This measure serves to receive particles in the interior of the flow body if necessary. Through different but smaller mesh size or openings, a multi-stage filter system can be formed, which filters out different particles from the liquid depending on the mesh size.

The flow of fluid within the filter housing can be of considerable importance. In order to optimize in particular the flow and filter conditions further exists a special variant of the filter assembly according to the invention therefore that the filter elements and / or the perforated plate with respect to a longitudinal axis in longitudinal section have a concave, trapezoidal or other curved or curved shape.

Accordingly, for the optimization of the back space behind the passage body for the flow conditions of relevance. An embodiment of the filter arrangement according to the invention also results from the fact that the rear space has a concave, trapezoidal or other curved or curved shape in longitudinal section with respect to a longitudinal axis. Further embodiments and advantages will become apparent from the subject of the dependent claims and the drawings with the accompanying descriptions. Embodiments are explained below with reference to the accompanying drawings. The invention should not be limited to the embodiments. Rather, embodiments are also considered, which now and in the future in an equivalent manner to the skilled person with other technical aids.

Short description of the drawing

1 shows a longitudinal section of a filter arrangement according to the invention for a fluid, in which the cleaning punch is arranged in a rest position.

FIG. 2 shows in a longitudinal section according to FIG. 1 a filter arrangement according to the invention for a fluid, in which the cleaning punch is shown in an operating position.

Fig. 3 shows in a longitudinal section a filter arrangement according to the invention for a fluid with a piston which has a working position in the filter housing, so that the flow body in the filter housing has an operating position, wherein the cleaning punch is in the rest position.

FIG. 4 shows, in a schematic longitudinal section according to FIG. 3, a filter arrangement according to the invention for a fluid with a piston which is provided in the working position in the filter housing, the cleaning ram being shown in an operating position.

5 shows, in a schematic longitudinal section according to FIGS. 3 and 4, a filter arrangement according to the invention for a fluid with a piston which is provided in the working position in the filter housing, the cleaning punch being shown in a final cleaning position.

FIG. 6 shows, in a schematic longitudinal section according to FIGS. 3-5, a filter arrangement according to the invention for a fluid in which the piston is provided in a change position in the filter housing for changing the flow body, the cleaning stamp being shown in the final cleaning position.

7 shows, in a schematic cross section, the filter arrangement according to the invention, in which the filter housing is shown with two pistons, two flow bodies, and cleaning punches disposed in the flow bodies.

8a shows a schematic longitudinal section of the filter arrangement according to the invention with a curved filter element in a first position of the cleaning ram in the rest position.

8b shows, in a schematic longitudinal section, the filter arrangement according to the invention with a curved filter element in a second position of the cleaning ram in working position.

8c shows in a schematic longitudinal section the filter arrangement according to the invention with a curved filter element in a third position of the cleaning ram in an end position.

8d shows a schematic longitudinal section of the filter arrangement according to the invention with a curved filter element in a fourth position of the cleaning punch in a screen change position in which the piston is led out of the filter housing.

9a shows, in a schematic longitudinal section, the filter arrangement according to the invention with a conical outer space in a first position of the cleaning ram in the rest position.

9b shows, in a schematic longitudinal section, the filter arrangement according to the invention with a conical outer space in a second position of the cleaning ram in the working position.

9c shows, in a schematic longitudinal section, the filter arrangement according to the invention with a conical outer space in a third position of the cleaning ram in an end position.

9d shows in a schematic longitudinal section the filter arrangement according to the invention with a conical outer space in a fourth position of the cleaning punch in a screen change position in which the piston is led out of the filter housing.

10 shows in a schematic cross section the filter arrangement according to the invention according to FIGS. 8a to 8d.

11 shows in a schematic cross section the filter arrangement according to the invention according to FIGS. 9a to 9d.

Preferred embodiment

In Fig. 1, 10 is a filter arrangement according to the invention for a fluid, such as liquid Plastic, called. The filter assembly 10 is shown in a longitudinal section. The filter assembly 10 comprises a filter housing 12, which is closed at its end face 14 with a housing cover 16. The housing cover 16 can be removed from the filter housing 12. The filter housing 12 has an inlet opening 18, to which an inlet channel 20 connects. The inlet channel 20 opens into an interior 22 of a flow body 24. The flow body 24 consists in the present embodiment of a cylindrical hollow body 26. The cylindrical hollow body 26 is formed by a perforated filter support wall 28. Openings 29 of the sieve-shaped filter support wall 28 can be adapted in their diameter to the material to be processed. This can be done by a suitable choice of the flow body 24 and the filter support wall 28. A cylindrical perforated plate 30 surrounds the flow body 24. Between the filter support wall 28 and the cylindrical perforated plate 30, a filter element 31 is provided. The filter element 31 consists in the present embodiment of a sieve, which can be varied in mesh size as needed.

Through the inlet channel 20, the fluid is pressed into the interior 22 of the flow body 24. Due to the pressure with which the fluid is pressed into the cylindrical hollow body 26, the fluid finally passes through the perforated filter support wall 28 into an outer space 32, which is located outside the flow body 24. The outer space 32 is defined here by the filter housing 12 and by the flow body 24. The outer space 32 is connected to an outlet channel 34, which opens into an outlet opening 36 of the filter housing 12.

In the interior 22 of the flow body 24 is a disc-shaped cleaning punch 38. The cleaning punch 38 is connected to a first side 39 with a flushing piston 40. The rinsing piston 40 extends substantially axially relative to the cylindrical hollow body 26, ie also parallel to the perforated filter support wall 28. The cleaning ram 38 has the form of a permeable wheel 42 with spokes 44. Peripheral side 46 of the cleaning ram 38 is in radial contact with the flow body 24 Spokes 44 are crossed with spoke channels 48. On the peripheral side 46 of the cleaning ram 38, a groove 50 is provided. The spoke channels 48 of the spokes 44 of the cleaning ram 38 are connected to the channel 50 with their 30 channel openings 52. In the flushing piston 40, a longitudinal channel 54 is provided axially, which is also connected to the spoke channels 48.

The flushing piston 40 extends through a central housing cover opening 56. The channel 54 of the flushing piston 40 is connected to the outer housing environment 58. Opposite the flushing piston 40, a drive piston 62 is provided on a second side 60 of the cleaning punch 38. The drive piston 62 is a part of a drive mechanism 64. About the drive mechanism 64, for example, from an electric drive with a Worm gear or a hydraulic drive can be made, the drive piston 62 is actively pushed or pulled axially to the cylindrical hollow body 26. Accordingly, the disk-shaped cleaning punch 38 moves through the interior 22 of the flow body 24 for cleaning.

The drive piston 62 is guided through a suitable sealed opening 66 of the filter housing 12. In the present illustration of FIG. 1, the cleaning punch 38 is in a rest position 68. The surface of the perforated filter support wall 28 can be fully utilized in the rest position 68 to clean the fluid flowing through the flow body 24 because the cleaning punch 38 does not form a portion of the perforated filter support wall 28 covers. The cylindrical perforated plate 30 is additionally provided around the flow body 24. The filter element 31 is located between the cylindrical perforated plate 30 and the perforated filter support wall 28.

2, the filter assembly 10 for a fluid according to FIG. 1 is also shown in longitudinal section. In contrast to FIG. 1, in FIG. 2 the cleaning punch 38 is in operation. As far as correspond to the two figures, therefore, the same reference numerals are used. The drive piston 62 has pushed the cleaning punch 38 into an operating region 70 of the interior 22 of the cylindrical hollow body 26 along a longitudinal axis 71. By pushing or pulling the cleaning ram 38, on the one hand, deposits are released from the perforated filter support wall 28.

The openings 29 of the perforated filter support wall 28 in the region 70 lie on the groove 50 of the peripheral side 46 of the cleaning ram 38. Since a higher pressure prevails in the outer space 32 than in the environment, the deposits on the other hand from the perforated filter support wall 28 ^" in the channel 50th The deposits are then discharged from the channel 50 through the spoke channels 48 and the longitudinal channel 54 of the scavenge piston 40 to the outer housing environment 58. The contact between the peripheral side 46 and the perforated filter support wall 28 is sealed The openings 29 are arranged annularly around the cylindrical hollow body 26, so that a sealing area 72 can always arise.

FIG. 3 shows an exemplary embodiment of a filter arrangement 110 according to the invention. The filter assembly 110 is shown as the previous figures in a schematic longitudinal section. The filter assembly 110 has a filter housing 112. In the filter housing 112, a piston 114 is provided in a piston guide 116. The piston 114 has at its one end a stop 115. The piston guide 116 terminates in a form-fitting manner with the piston 114. In the filter housing 112, an inlet opening 118 with an inlet channel 120 and an outlet opening 122 with an outlet channel 124 are provided. The inlet channel 120 opens into a cylindrical cavity 126 of the piston 114th

In a section 128, a changeable flow body 132 is arranged in a wall 130 of the piston 114. While the piston 114 is provided with the piston guide 116 in a form-fitting manner, the flow body 132 is at a distance from the filter housing 112 or the piston guide 116. The spacing results in an outer space 133 to the Dürchflusskörper 132. The outlet channel 124 is connected to the outer space 133 of the flow body 132.

The flow body 132 forms a cylindrical hollow body 134, the interior 136 of which is in communication with the cavity 126 of the piston 114. The cylindrical hollow body 134 is formed by a secured filter support wall 138. The filter support wall 138 is disposed in the portion 128 of the piston 114. A cylindrical perforated plate 140 surrounds the flow body 132. Between the filter support wall 138 and the cylindrical perforated plate 140, a filter element 142 is provided. The filter element preferably consists of a sieve whose mesh size can be adapted to the contamination of the fluid.

The cavity 126 of the piston 114 is closed with a cover cover 144. For this purpose, the end cover 144 is inserted into the piston 114 in a form-fitting manner. The end cover 144 has a largely central passage opening 146, through which a rinsing piston 148 of a cleaning ram 150 is guided. The cleaning punch 150 has the form of a permeable wheel 152 with spokes 154. In principle, other shapes are conceivable in place of the wheel 152, such as a rectangular or an oval shape. Essentially centrally, the flushing piston 148 is disposed perpendicularly and axially to the permeable wheel 152. In the flushing piston 148, a longitudinal passage 156 is provided axially, which is also connected to spoke channels 160. Peripheral side 158 of the cleaning punch 150 is in radial contact with the flow body 132. The spokes 154 are crossed with spoke channels 160. On the peripheral side 158 of the cleaning punch 150, a groove 162 is provided. The spoke channels 160 of the spokes 154 of the cleaning punch 150 are connected to the channel 162 with their channel openings 164.

The longitudinal channel 156 of the flushing piston 148 is connected to the outer environment 166 of the filter housing 112. In the present illustration of FIG. 3, the cleaning punch 150 is in a rest position 168. The surface of the perforated filter support wall 138 can be fully utilized in the rest position 168 for cleaning the fluid flowing through the flow body 132.

The mode of operation of the cleaning punch 150 can be seen analogously to FIGS. 1 and 2 already described. Accordingly moves in this embodiment of the Cleaning punch 150 for cleaning, as shown in Figures 4 and 5, along a longitudinal axis 169. In Fig. 4, an operating state of the cleaning punch 150 is shown. In Fig. 5, the final state of the cleaning punch 150 is shown after a cleaning pass. As far as Fig. 4 and Fig. 5 correspond to Fig. 3, the same reference numerals are used here. The cleaning punch 150 moves during the ongoing operation of the machine, for example, for the processing of liquid plastic, along the longitudinal axis 169 of the flow body 132 to the end position shown in FIG. In doing so, the cleaning punch 150 removes adhering contaminants.

Despite the cleaning punch 150, it often happens that the flow body 132 must be replaced. On the one hand, this is due to the fact that the flow body 132 wears out and, on the other hand, is so contaminated that it can no longer be used as intended. In Fig. 6, the filter assembly 110 according to the invention is shown, in which the piston 114 is inserted via the piston guide 116 into the filter housing 112 to the stop 115. In this position, the stop 115 opposite piston end 170 of the piston 114 projects out of the filter housing 112. In this piston end 170 of the flow body 132 is located. The flow body 132 is now accessible from the outside. The cleaning punch 150 is pushed to the position of the final state as shown in FIG. 5.

In this position, the piston 114 is in a change position 172 for the flow body 132. In this change position 172, the filter elements 142, the filter support wall 138 and the cylindrical perforated plate 140 can be cleaned or replaced if necessary. The piston 114 closes in this change position 172 the inlet channel 120 and the outlet channel 124. To move the piston 114 and the cleaning punch 150, a drive, not shown, is provided. In each case, a separate drive or a common drive can be provided.

FIG. 7 schematically shows the cross section of the filter arrangement 110 according to the invention. In the filter housing 112, two parallel pistons 114 are arranged with two flow bodies 132. In the flow bodies 132, the cleaning punches 150 are shown accordingly. As far as Fig. 7 corresponds to Figures 3 to 6, the same reference numerals are used here. The pistons 114 can be moved asynchronously in their piston guides 116. As a result, for example, the change of the flow body 132 and the filter elements 142 take place alternately. This has the consequence that the machine for changing the flow body 132 or the filter elements 142 or other parts of the filter assembly 110 does not have to be issued. In each case, the other flow body 132 takes over the corresponding filter function in the moment of change. The cleaning punches 150 can also be operated asynchronously. The fluid, which is indicated by arrows 174, flows through the inlet opening 118 into the inlet channels 120. Each flow body 132 is assigned a separate inlet channel 120. After the fluid has flowed through the flow body 132, as described above, for filtering, it finally reaches the outlet channels 124. Via the outlet channels 124, the fluid is supplied to the outlet opening 122 for further processing in the machine. By axially displacing the piston 114, the associated inlet channel 120 and the associated outlet channel 124 are blocked respectively. The flow body 132 can be serviced or changed. The filtering function is then performed by the parallel flow body 132, which is preferably in an operating position.

In FIG. 8a, as for example in the preceding FIGS. 5 and 6, in a schematic longitudinal section a further variant of a filter arrangement 210 according to the invention is shown. FIG. 8 a and the following FIGS. 8 b to 8 d essentially differ from the previous exemplary embodiments in the shape of the flow body 238. FIGS. 8 a to 8 d show the different working positions of the filter arrangement 210.

The filter assembly 210 has a filter housing 212. In the filter housing 212, a piston 214 is provided in a piston guide 216. The piston 214 has a stop 218 at one end. The piston guide 216 closes positively with the piston 214. In the filter housing 212, an inlet opening 220 with an inlet channel 222 and an outlet opening 224 with an outlet channel 226 are provided. The inlet channel 220 opens into a cavity 228 of the piston 214. In this embodiment of the filter assembly 210, a curved filter element 230 is shown. In this case, the piston 214 is in a first position in the rest position 232.

In a section 234, a removable flow body 238 is arranged in a wall 236 of the piston 214. While the piston 214 is provided with the piston guide 216 in a form-fitting manner, the flow body 238 is at a distance from the filter housing 212 or the piston guide 216. The spacing creates a rear space 240 to the flow body 238. The exit passage 226 is connected to the rear space. 240 of the flow body 238 connected.

The flow body 238 is disposed in the portion 234 of the piston 214. A filter support wall 248 forms with a perforated plate 250 the flow body 238. Between the perforated plate 250 and the filter support wall 248, a filter element 252 is provided. The filter element 252 preferably consists of a sieve whose mesh size can be adapted to the contamination of the fluid.

The flow body 238 has in the longitudinal section substantially the shape of two opposite trapezoids 254a and 254b. The flow body 238 is replaced by a bulbous shape. Both the perforated plate 250 and the filter element 252 therefore also have, in longitudinal section, essentially a shape of the two opposite trapezoids 254a and 254b, which are arranged along their longer side parallel to the longitudinal axis 256 of the piston 214.

Instead of the trapezoids 254a, 254b may also be provided a concave or other curvy shape. The shape of the flow body 238 or the perforated plate 250 and the filter element 252 has an influence on the flow of the fluid 174. The adaptation option of the shapes for the filter element 252 or the perforated plate 250 can optimize various parameters of the flow, for example with respect to the flow direction, flow velocity and flow rate Viscosity of the substance to be filtered, etc. are made. Here, an individual optimization and adaptation of the flow body 238 can be carried out.

The cavity 246 of the piston 214 is closed with a cover plate 258. For this purpose, the end cap 258 is recessed into the piston 214 in a form-fitting manner. The end cover 258 has a largely central passage opening 260, through which a flushing piston 262 of a cleaning punch 264 is guided. The cleaning punch 264 is in the form of two opposing jaws 266. Substantially centrally, the flushing piston 262 is disposed perpendicularly and axially to the jaws 266. In the flushing piston 262, a longitudinal channel 270 is provided axially, which is also connected to spoke channels 272.

The longitudinal channel 270 of the flushing piston 262 is connected to the external environment 280 of the filter housing 212. In the present illustration of FIG. 8a, the cleaning punch 264 is in a rest position 232. The surface of the perforated filter support wall 248 can be fully utilized in the rest position 232 for cleaning the fluid flowing through the flow body 238.

The operation of the cleaning punch 264 is analogous to the previously described figures. Accordingly, in this embodiment too, the cleaning punch 264 moves along the longitudinal axis 256 for cleaning.

In Fig. 8b, an operating state of the cleaning punch 264 is shown. The cleaning punch is located in a working position 282, in which the filter element 230 as described above, is cleaned. FIG. 8c shows an end position 284 of the cleaning punch 264 after a cleaning cycle. The cleaning punch 264 passes from the rest position 232 according to FIG. 8a during operation of the machine, for example for processing liquid plastic, along the longitudinal axis 256 through the flow body 238 up to the end position 284 according to FIG. 8c. It removes the Cleaning stamp 264 adhering contaminants.

In Fig. 8d, the filter assembly 210 according to the invention is shown, in which the piston 214 is inserted via the piston guide 216 in the filter housing 212 to the stop 218. In this position, the stop 218 opposite piston end 286 of the piston 214 projects out of the filter housing 212. In this piston end 286 of the flow body 238. The flow body 238 is now accessible from the outside. The cleaning punch 264 is pushed to the position of the final state, as shown in Fig. 8c.

In this position, the piston 214 is in a change position 288 for the flow body 238. In this change position 288, the filter elements 252, the filter support wall 248 and the perforated plate 250 can be cleaned or replaced if necessary. The piston 214 closes in this change position 288 the inlet channel 222 and the outlet channel 226. To move the piston 214 and the cleaning punch 264, a drive, not shown, is provided. In each case, a separate drive or a common drive can be provided.

FIG. 9a shows a further exemplary embodiment of a filter arrangement 290 according to the invention in a schematic longitudinal section. In a filter housing 292 is a piston 294 which is slidably disposed in a piston guide 295 of the filter housing 292. In contrast to the previous embodiments, only a single flat flow body 296 is provided in a portion 293 of the piston 294. Namely, in the previous embodiments, the flow body 24 or 132 forms a hollow body 26, 134. The flow body 296 is arranged in the portion 293 of the piston 294 in its wall 297. FIGS. 9a to 9d show the different operating positions of the filter arrangement 290.

The inlet passage 300 leads the fluid 174 into an antechamber 302. The flow body 296 contains a filter element 304, a filter support wall 306 and a perforated plate 308, which are planar. As soon as the fluid 174 has flowed through the flow body 296, it flows into a cone-shaped rear space 310. The conical-shaped rear space 310 is located in the piston 294 and ends in an outlet channel 312. The outlet channel 312 terminates in an outlet opening 314 of the filter housing 292.

The flow body 296 is changeably arranged in the piston 294. While the piston 294 is provided with a positive fit with the piston guide 295, the flow body 296 is spaced from the filter housing 292 and the piston guide 295. As a result of the spacing, in particular the antechamber 302 to the flow body 296 is formed. In the vestibule 302 is a cleaning punch 316. The cleaning punch 316 has a ladder-like shape, the rungs 318 are crossed with channels 320. A flushing piston 322 is arranged substantially centrally, perpendicularly and axially to the cleaning punch 316. In the flushing piston 322, a longitudinal channel 324 is provided axially, which is connected to the channels 320. The channels 320 of the rungs 318 of the cleaning punch 316 are connected with their channel openings 278 with a groove 326.

The longitudinal channel 324 of the flushing piston 322 is connected to the outer environment 328 of the filter housing 292. In the present illustration of FIG. 9 a, the cleaning punch 316 is in a rest position 327. The surface of the filter element 304 can be fully utilized in the rest position 327 for cleaning the fluid flowing through the flow body 296.

The operation of the cleaning punch 316 is analogous to the previously described figures. Accordingly, in this embodiment as well, the cleaning punch 316 moves along a longitudinal axis 330 for cleaning.

FIG. 9b shows, in a schematic longitudinal section, the filter arrangement 290 according to the invention with the conical outer space 310 in a second position of the cleaning punch 316 in such a working position 332. The cleaning punch 316 is guided along the flow body 296 analogously, as in the previous exemplary embodiments. In this case, contamination is conveyed by negative pressure through the longitudinal channel 324 of the flushing piston 322 to the outside.

In Fig. 9c, an end position 334 of the cleaning punch 316 is shown after a cleaning pass. From the rest position 327 of the cleaning punch 316, the latter drives according to FIG. 9b during operation over the surface of the flow body 296 up to the end position 334 according to FIG. 9c. The cleaning punch 316 removes adhering contaminants.

Although the cleaning punch 264 thoroughly cleans the flow body 296, it may be necessary to replace the flow body 296 for wear and extreme contamination or clogging. In Fig. 9d, the filter assembly 290 is shown, in which the piston 294 is inserted via the piston guide 295 in the filter housing 292 up to a stop 336 of the piston 294. In this position, the stop 336 opposite piston end 338 of the piston 294 protrudes from the filter housing 292 out. In this piston end 338 of the flow body 296 is arranged. From the outside, the flow body 296 is accessible for a change. The cleaning punch 264 is pushed to the position of the final state, as shown in Fig. 9c. In this position, the piston 294 is in a change position 340 for the flow body 296. In this change position 340, the filter elements 304, the filter support wall 306 and the orifice plate 308 can be cleaned or replaced if necessary. The piston 294 closes in this change position 340 the inlet channel 300 and the outlet channel 312nd

FIG. 10 shows in a schematic cross section the filter arrangement 210 according to the invention according to FIGS. 8a to 8d. As far as Fig. 10 coincides with Figs. 8a to 8d, the same reference numerals are used. In the filter housing 212, the piston 214 is disposed in the piston guide 216. The piston guide 216 closes positively with the piston 214. The cavity 228 of the piston 214 forms the antechamber 244 and is connected to the not visible here inlet channel 222. The rear space 240 is provided outside the flow body 238 and is formed by the piston guide 216 and the flow body 238. The rear space 240 is connected to the outlet channel 226 and the outlet opening 224, not visible here, in conjunction.

In a section 234, the exchangeable flow body 238 is inserted in a form-fitting manner in the wall 236 of the piston 214. The filter support wall 248 forms with the perforated plate 250, the flow body 238. Between the perforated plate 250 and the filter support wall 248, the filter element 252 is provided. The filter element 252 preferably consists of a sieve whose mesh size can be adapted to the contamination of the fluid. The cleaning punch 264 is in the form of two opposing jaws 266. Substantially centrally, the flushing piston 262 is disposed perpendicularly and axially to the jaws 266. In the flushing piston 262, a longitudinal channel 270 is provided axially, which is also connected to spoke channels 272.

FIG. 11 shows in a schematic cross section the filter arrangement 290 according to the invention according to FIGS. 9a to 9d. As far as Fig. 11 corresponds to Figs. 9a to 9d, the same reference numerals are used.

In the filter housing 292 is the piston 294, which is arranged displaceably in the piston guide 295 of the filter housing 292. In the section 293 of the piston 294, the flow body 296 is provided. The flow body 296 is embedded in the portion 293 of the piston 294 in the wall 297. The inlet channel 300 leads the fluid 174 into an antechamber 302. The flow body 296 comprises the filter element 304, the filter support wall 306 and the perforated plate 308. As soon as the fluid 174 reaches the flow body 296 flows through, it flows into the cone-shaped rear space 310. The conical-shaped rear space 310 is located in the piston 294 and communicates with the Outlet passage 312 and the outlet opening 314 of the filter housing 292 in conjunction.

The flow body 296 is changeably arranged in the piston 294 as described. While the piston 294 is provided with a positive fit with the piston guide 295, the flow body 296 is spaced from the filter housing 292 and the piston guide 295. As a result of the spacing, in particular the antechamber 302 to the flow body 296 is formed.

The cleaning punch 316 has a "ladder-like" shape whose rungs 318 are traversed by the channels 320. The rinsing piston 322 is arranged substantially centrally, perpendicularly and axially to the cleaning ram 316 A longitudinal channel 324 is provided axially, which is connected to the channels 320. The channels 320 of the rungs 318 of the cleaning punch 316 are connected to their channel openings 278. The longitudinal channel 324 of the flushing piston 322 is connected to the outer environment 328 of the filter housing 292.

LIST OF REFERENCE NUMBERS

10 Filter arrangement 110 Filter arrangement

 12 filter housing 112 filter housing

 14 front 114 pistons

 16 housing cover 115 stop

 18 inlet opening 116 piston guide

 20 inlet channel 118 inlet opening

 22 Interior 120 inlet channel

 24 flow body 122 outlet opening

 26 cylindrical hollow body 124 outlet channel

 28 Holes filter support wall 126 cavity

 29 openings 128 section of the piston

30 Cylindrical perforated plate 130 Wall of the piston

31 filter element 132 flow body

32 outdoor space 133 outdoor space

 34 outlet channel 134 hollow body

 36 outlet opening 136 interior

 38 Cleaning punch 138 Filter support wall

 39 First page of cleaning stamp 140 Cylindrical perforated plate

40 rinsing piston 142 filter element

 42 wheel 144 end cap

 44 spokes 146 passage opening

46 Peripheral side 148 Flushing piston

 48 spoke channels 150 cleaning punches

50 gutter 152 Permeable wheel

52 channel openings 154 spokes

 54 Longitudinal channel in the flushing piston 156 Longitudinal channel in the flushing piston

56 Housing cover opening 158 peripheral side

 58 Outer Casing Environment 160 Spoke Channels

 60 Second side of the cleaning punch 162 gutter

 62 drive piston 164 duct openings

 64 Drive mechanism 166 Outside environment

66 opening of the filter housing 168 rest position of the

 cleaning stamp

68 Rest position 169 Longitudinal axis

 70 Operating range 170 Piston end

 71 longitudinal axis 172 change position of

 piston

72 Sealing area 174 Fluid 210 Filter arrangement 286 Piston end

 212 Filter housing 288 Change position

214 piston 290 filter assembly

216 Piston guide 292 Filter housing

218 stop 293 section

 220 inlet opening 294 pistons

 222 inlet channel 295 piston guide

224 Outlet opening 296 Flow body

226 exit channel 297 wall

 228 cavity of the piston 298 inlet opening

230 filter element 300 inlet channel

232 Rest position 302 Anteroom

 234 Section 304 Filter element

236 Wall of the piston 306 Filter support wall

238 flow body 308 perforated plate

 240 rear room 310 rear room

 244 vestibule 312 outlet channel

246 cavity of the piston 314 outlet opening

248 Filter support wall 316 Cleaning punch

250 perforated plate 318 sprouts

 252 filter element 320 channels

 254a, 254b Trapeze 322 Flushing piston

 256 longitudinal axis 324 longitudinal channel

258 End cover 326 gutter

 260 passage opening 327 rest position

262 Flushing piston 328 External environment

264 cleaning punch 330 longitudinal axis

 266 Claws 332 Working position of the

 cleaning stamp

270 longitudinal channel 334 end position of the

 cleaning stamp

272 spoke channels 336 stop

 278 duct openings 338 piston end

280 Outside environment 340 Change position

282 working position of the

 cleaning stamp

 End position of the cleaning punch

Claims

claims A filter assembly (10, 110) for a fluid (174) having a filter housing (12, 112), wherein a) the filter housing (12, 112) contains an inlet opening (18, 118) for an inlet channel (20, 120) and an outlet opening (36, 122) for an outlet channel (34, 124), b) a flow body (24, 132) is provided in the filter housing (12, 112), c) the flow body (24, 132) has a filter support wall (28, 138), whereby a hollow body (26, 134) with an interior space ( 22, 136) and an outer space (32) is created, d) the inner space (22, 136) is coupled to the inlet channel (20, 120) and the outer space (32) is connected to the outlet channel (34, 124), e) in the filter support wall (28, 138) openings (29) are provided through which the fluid (174) is passed for filtering, f) a displaceable cleaning punch (38, 150) is provided which removes deposits on the filter support wall (28, 138), characterized in that g) the flow body (24, 132) in a portion (128) of a piston (114) is provided, wherein the piston (114) in the filter housing to a stop (115) in a piston guide (116) is displaceable, so that the flow body (24, 132) for changing out of the filter housing (12, 112) is guided. Second filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to claim 1, characterized in that the first flow body (24, 132) corresponding second flow body (24, 132) in the filter housing (12, 112) in a second piston (114) is arranged, wherein the second piston (114) in the filter housing (12, 112) to a stop (115) in a piston guide (116) is slidably formed, so that the second flow body (24, 132) for changing out of the filter housing (12, 112) is guided. 3. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to claim 2, characterized in that the piston (114) for changing the flow body (24, 132) asynchronously displaceable in the piston guides ( 116) are provided. 4. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to any one of claims 2 or 3, characterized in that for each flow body (24, 132) each have an inlet channel (20, 120) and an exit channel (34, 124) is provided. 5. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 2 to 4, characterized in that the cleaning punches (38, 150) are provided asynchronously displaceable. 6. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 5, characterized in that the hollow body (26, 134) is substantially cylindrical. 7. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 6, characterized in that the cleaning punch (38, 150) to the filter support wall (28, 138) in parallel arranged flushing piston (40,148) having a channel (54, 156). 8. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to claim 7, characterized in that on the periphery (46, 158) of the cleaning punch (38, 150) has a groove (50, 162) is provided, which is connected to the channel (54, 156) of the Spülkölbens (40, 148) via a spoke channel (48, 160). 9. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 8, characterized in that a drive mechanism (64) for the cleaning punch (38, 150) is provided, which guides the cleaning punch (38, 150) along the filter support wall (28, 138). 10. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 6 to 9, characterized in that the openings (29) annularly around and in the filter support wall (28, 138) are arranged. 11. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 10, characterized in that the inlet channel (20, 120) with the interior (22, 136) and / or the outlet channel (34,124) is connected to the outer space (32). 12. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 11, characterized in that the filter housing (12, 112) a detachable housing cover (16, 144) through which the flushing piston (40, 148) is guided. 13. A filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to any one of claims 1 to 12, characterized in that a pressure generator, which the fluid (174) with pressure in the interior (22 , 136) of the flow body (24, 132) for filtering presses. 14. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 13, characterized in that a filter element (31, 142) in the outer space (32) on the filter support wall ( 28, 138) of the hollow body (26, 134) is arranged. 15. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 14, characterized in that a filter element (31, 142) is arranged between the hollow body (26, 134). and a hollow plate (26, 134) surrounding the perforated plate (30, 140) is arranged. 16. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 15, characterized in that a filter element (31, 142) in the interior (22, 136) on the Hollow body (26, 134) is arranged. 17. Filter arrangement (10, 110) for a fluid (174) with a filter housing (12, 112) according to one of claims 1 to 16, characterized in that the filter elements (31, 142) and / or the cylindrical perforated plate (30, 140) with respect to a longitudinal axis (71, 169) in longitudinal section have a concave, trapezoidal or other curved shape. 18. A filter arrangement (210, 290) for a fluid (174) with a filter housing (212, 292), wherein a) the filter housing (212, 292) has an inlet opening (220, 298) for an inlet channel (222, 300) and an outlet opening (224, 314) for an outlet channel (226, 312), b) a flow body (238, 296 c) the flow body (238, 296) has a filter support wall (248, 306) with an antechamber (244, 302) and a rear space (240, 310), d) the antechamber (244, 302) is coupled to the inlet channel (222, 300) and the rear chamber (240, 310) is coupled to the outlet channel (226, 312), e) in the filter support wall (248, 306) openings (29) are provided by the fluid (174) is directed to filter, f) a slidable cleaning punch (264, 316) is provided which removes deposits on the filter support wall (248, 306), characterized in that g) the flow body (238, 296) is provided in a portion (128) of a piston (214, 294), wherein the piston (214, 294) in the filter housing (212, 292) up to a stop (218, 336) in a piston guide (216, 295) is designed to be displaceable, so that the flow body (238, 296) for changing out of the filter housing (212, 292) is guided. 19. A filter arrangement (210, 290) for a fluid (174) with a filter housing (212, 292) according to claim 17, characterized in that the flow body (238, 296) has a concave, trapezoidal or other domed shape. 20. Filter arrangement (210, 290) for a fluid (174) with a filter housing (212, 292) according to one of claims 18 to 19, characterized in that the rear space (240, 310) to the outlet opening (224, 314) opposite to a Longitudinal axis (256, 330) has a concave, trapezoidal, conical or other curved shape in longitudinal section.