A filtration device comprising a main filter unit and an auxiliary filter unit, and a filter circuit using the same.

Abstract

The invention relates to a filtering device for a fluid comprising a filter housing 11 having an inlet, a main filter unit 20 in the filter housing 11, a filtrate outlet for filtrate filtered at a main filter surface 21 of the main filter unit, and an auxiliary filter unit 30 for treating backflow fluid accumulating during backflow of the main filter surface. The main filter surface 21 is partially cleanable by backflow, the backflow element allowing a continuous partial backflow of the main filter surface 21. To ensure good cleaning of the fluid with little fluid loss occurring, the auxiliary filter unit 30 in the housing 11 is provided with a backflow device operable at intervals, and a treatment unit 40 for treating the dirty fluid accumulating during backflow is connected downstream of the backflow device.

Description

Technical Field

[0001] The present invention relates to a filtration device for fluids, particularly lubricating oils or fuels, comprising a filter housing having a fluid inlet, a main filter unit provided with a rotatable backflush element arranged in the filter housing, a filtrate outlet for the filtrate filtered at the main filter surface of the main filter unit and generated at that point, and an auxiliary filter unit for treating the backflush fluid accumulating between the backflushes of the main filter surface of the main filter unit, wherein the main filter surface of the main filter unit can be partially cleaned by the backflush by the backflush element, and the backflush element enables a continuous partial backflush of the main filter surface. The present invention also further relates to a filter circuit comprising at least one consumer to which fluid can be supplied as fuel or lubricating oil, a fluid tank, and a filtration device arranged in the circuit between the fluid tank and the consumer.

Background Art

[0002] Filtration devices for fuels or lubricating oils are used in engines for vehicles and many machines. In order to improve the service life of the corresponding filtration device, it is known to provide a filtration device with at least one unit designed as an automatic filter that can be backflushed. At this time, the filter surface of the filter unit can be partially cleaned by the backflush by the backflush element, while the filter surface of the filter unit that does not receive the backflush is available for the filtration process, so that the consumer is permanently supplied with fuel or lubricating oil.

[0003] It is also known that several filter units are connected in series or in parallel, with one unit forming a main filter and another forming an auxiliary filter. Furthermore, it is known that the backflow fluid generated during the backflow is processed in order to make a portion of the backflow fluid that has been processed by the filtering process still available as fuel or lubricant. For example, it is known that the processing is connected to a centrifuge at the outlet for the backflow fluid, in which case only the solids remain.

[0004] In particular, the available installation space is limited, especially for vehicles. This applies not only to land vehicles or agricultural machinery, but especially to ships, where, on the one hand, filtered waste particles must be stored on board until they reach a port where they can be disposed of, and on the other hand, the supply of further lubricating oil or fuel may only be covered at the next port. [Overview of the project] [Problems that the invention aims to solve]

[0005] The objective of this invention is to create a filtration device that has a simple structure and produces minimal fluid loss, ensuring effective cleaning of the fluid. [Means for solving the problem]

[0006] To solve this problem, the present invention proposes that an auxiliary filter unit is disposed in the filter housing of the main filter unit, and preferably an interval-operable or operable backflow device is provided to wash the filter surface of the auxiliary filter unit, preferably at intervals, and the backflow device has a downstream treatment unit to treat the sludge fluid that accumulates during backflow of the filter surface of the auxiliary filter unit. The solution according to the present invention therefore provides a plurality of at least double backflow oil treatments integrated in the housing of the main filter unit, i.e., a backflow oil treatment comprising an auxiliary filter unit that can be backflowed again on one side, and further a treatment unit connected downstream of the auxiliary filter unit, where the sludge particles are concentrated in (at least) two stages.

[0007] In a particularly preferred design of the filter device according to the present invention, the processing unit is arranged in the filter housing together with the main filter unit and the auxiliary filter unit. Thus, all three units are located in the same housing, which simultaneously enables an optimally compact structure and, by extension, a minimum size of the housing with extremely short, and therefore low-loss, flow paths for the fluid.

[0008] According to the advantageous design, the backflow element for the main filter unit is connected to a flushing fluid line within the filter housing that opens to the inlet of the auxiliary filter unit.

[0009] More preferably, the backflow device of the auxiliary filter unit may have a backflow member that can be rotated at intervals, and the backflow member is preferably connected to a fluid line in the filter housing that opens to the inlet of the processing unit. As already mentioned, this allows for an extremely short flow path for the fluid. The spaced operation of the auxiliary filter unit ensures, among other things, that sufficient input pressure is available for the auxiliary filter unit, which is ensured in a particularly advantageous way when the main filter unit is designed as a permanent flusher.

[0010] For numerous possible applications, it is particularly advantageous if the filter housing has a connecting flange, thereby allowing the filtration device to be directly connected as an add-on component to a consumer, such as a marine engine, land vehicle, machine, or tank engine. The flange can form an inlet connection for the fluid to be filtered, which may also preferably form a filtrate outlet. At the same time, the flange can ensure that the entire filtration device is advantageously aligned horizontally.

[0011] The treatment unit, in this case, is preferably constructed in a particularly simple manner and may have a double filter with a single replaceable filter insert or a filter insert that is therefore not backflow-proof. Alternatively, or preferably additionally, the treatment unit may have or may form a sedimentation space comprising a closed base and a filter surface positioned above the base and capable of flowing from inside to outside. Advantageously, filtration of highly concentrated fouling material via sedimentation is thus brought about by the treatment unit. For this purpose, it is particularly advantageous that the treatment unit allows inflow into the sedimentation space from above and that the filter insert forming the sedimentation space is replaceable. Similarly, the functionality of the treatment unit as a sedimentation chamber is particularly effective when an auxiliary filter unit connected upstream is operated only at intervals, as this allows for a longer period for the sediment to be treated without subsequent flowing fluid.

[0012] To ensure that fluid flow to the consumer is always guaranteed regardless of the functionality of the individual filter units within the housing, it is particularly convenient to provide the main filter unit with an overflow valve as a bypass, fixed by a separate filter element. Alternatively or additionally, a valve that can be switched by a control device may be connected between the auxiliary filter unit and the processing unit, and the backflow device for the auxiliary filter unit is active only when the valve is open. Switching the valve allows for simultaneous provision and control of the functionality of the auxiliary filter unit at intervals.

[0013] A filtration device according to the present invention having the aforementioned structure can be particularly advantageously used in a filter circuit comprising a fluid tank and at least one consumer to which a fluid can be supplied as fuel or lubricant, in which case the filtration device is located in the circuit between the fluid tank and the consumer. In a filtration device comprising three different units, a main filter unit, an auxiliary filter unit and a processing unit, integrated in the same housing according to one design of the circuit, the filtrate outlet behind the main filter unit, the clean fluid outlet behind the auxiliary filter unit and / or the fluid outlet behind the processing unit can be connected to the same consumer, for example, an engine in particular, or alternatively, a common outlet for the cleaned fluid / filtrate / clean fluid can be further provided to the housing. In this design, in particular, if the auxiliary filter unit has a filter surface with a filter material having a filter fit that is at least as good as that of the main filter unit, the entire filtered portion of the backflow fluid accumulating in the auxiliary filter unit can be supplied directly to the consumer, thereby saving some resources.

[0014] Alternatively, the filtrate outlet at the rear of the main filter unit can be connected to a consumer, such as an engine, while the clean fluid outlet at the rear of the auxiliary filter unit and the fluid outlet at the rear of the treatment unit are connected to a storage tank for the fluid, and the consumer is preferably also connected to the fluid tank via a discharge line for the fluid. This mode of operation permanently improves the degree of lubrication oil compatibility because filtered contaminant particles are permanently drawn out of the circuit.

[0015] Basically, the fluid pressure in the fluid tank can be sufficient so that filtration can be performed in a filtration device with three units. In most applications, however, it is advantageous if a main pump is connected between the fluid tank and the filtration device.

[0016] Further advantages and designs of the filtration device according to the present invention, as well as circuits having the same, are derived from the following description of the advantageous exemplary embodiments shown in the drawings. The drawings show the following: [Brief explanation of the drawing]

[0017] [Figure 1] The basic structure of the filtration device according to the present invention, which has three integrated units for multi-stage filtration of fluids, is schematically shown in the diagram. [Figure 2] The circuit structure of a circuit equipped with the integrated filter device according to the present invention is schematically shown by a circuit diagram. [Figure 3] The circuit diagram schematically illustrates the structure of a circuit with an integrated, slightly modified filtration device according to the present invention, along with a pump between the fluid tank and the filtration device. [Figure 4] A simplified cross-sectional view of the housing, which includes three units integrated into the main filter unit housing, is schematically shown. [Modes for carrying out the invention]

[0018] Figure 1 shows, in a highly simplified block diagram, the basic structure of a filtration device according to the present invention, collectively indicated by reference numeral 10, for filtering lubricating oil or fuel in a wing in front of a consumer 1, for example, a ship's engine. It goes without saying that the same filtration device 10 can be supplied to several consumers, and possibly different ones, especially when the fluid flowing through the filtration device is lubricating oil. The filtration device 10 has three units integrated in a housing 11, namely a main filter unit 20, an auxiliary filter unit 30, and a processing unit 40, shown schematically here. The main filter unit 20 is designed as an automatic filter that can be backflowed. Fluid enters the main filter unit 20 from the fluid tank 2 through the inlet of the housing 11. The maximum portion flow of the fluid is filtered in the main filter unit 20 and then supplied to consumer 1 as filtrate, as indicated by the flow arrow 29. Due to the backflow process, the portion of the backflowing fluid that accumulates in the main filter unit 20, as indicated by the flow arrow 28, is supplied to the auxiliary filter unit 30 located in the housing 11. The portion of the clean fluid that has been filtered or free of contaminants in the auxiliary filter unit 30 is supplied to the fluid tank 2, as indicated by the flow arrow 39. The auxiliary filter unit 30 is also capable of backflow according to the present invention, so that a portion of the concentrated contaminant liquid is simultaneously generated, as indicated by the flow arrow 38, and this is supplied again to the third processing unit 40 located in the housing 11. Fluid flow of the treated fluid is also generated in the processing unit 40 and supplied to the fluid tank 2, as indicated by the flow arrow 49; furthermore, a portion of relatively high-concentration contaminants is generated, which is supplied to the contaminant fluid storage tank 50, as indicated by the flow arrow 48 in the illustrated exemplary embodiment.However, this is only a general overview, because the treatment unit preferably consists of a replaceable filter insert in which all the contaminants are retained, and when a level of contamination of the filter material is reached with contaminants, it is then replaced with another filter insert, so that all the contaminants remain in the filter insert. The treatment filter therefore generally does not have an outlet for contaminant fluid, but only an outlet for clean or treated fluid.

[0019] The diagram in Figure 2 is a circuit representation of the basic structure of the filtration device shown in Figure 1; the same reference numerals are therefore used; in the diagram in Figure 2, the fluid tank 2 is integrated into the consumer 1, for example, the base of an engine. A supply line 3 runs from the fluid tank 2 into the fluid inlet 12 of the housing 11 of the filtration device 10. The fluid then flows into the inlet of the main filter unit 20, where it flows through a very short channel, and is filtered by the main filter surface 21 of the main filter unit 20, depending on the suitability of the filter media on the main filter surface 21. The corresponding filtered portion of the fluid flow exits the housing behind the main filter surface 21 of the main filter unit 20 via the filtrate outlet 13 of the housing 11 and can be supplied to the consumer as filtered fluid via the filtrate supply line 14. Since the main filter unit 20 is capable of backflow, and it is preferably provided with a backflow element for permanent, partial backflow on a portion of the main filter surface 21, as described with reference to Figure 4, a fluid flow of backflow fluid is generated in the main filter unit 20 during backflow, preferably by backflow filtrate, preferably permanently in the opposite direction to the filtration device, and this fluid flow exits the main filter unit 20 at an internal flushing fluid outlet 22 and enters the auxiliary filter unit 30 via an internal fluid line 25; for this purpose, this has an inlet indicated by reference numeral 32. At the auxiliary filter surface 31 of the auxiliary filter unit 30, the actual fluid flow of backflow fluid is filtered again, and a fluid flow of filtered clean fluid is generated, which exits from the housing 11 of the filtration device 10 at a clean fluid outlet 15 and also via a separate line 16 and is also supplied to the consumer 1. According to the present invention, the auxiliary filter unit 30 can also be backflowed and, as described with reference to Figure 4, has a backflow member for this purpose so that a partial flow with a higher concentration of waste is again generated, which is supplied to a third processing unit 40 located in the housing 11 via an internal line 61. The auxiliary filter unit 30 is preferably operated at intervals, for which a controllable valve 60 is located in the internal line 61. The backflow of the auxiliary filter surface 31, preferably partial, occurs only when the valve 60 is open.Behind valve 60, line 61 opens into the inlet of processing unit 40. This also has a filter surface 41, which is preferably a single filter, in particular a filter insert that can flow from inside to outside, as will be explained with reference to Figure 4. The fluid flow passing through the filter surface 41 of processing unit 40 exits the housing 11 as treated clean fluid via fluid outlet 18 and can also be supplied to consumer 1 via a further separate line 19. All contaminant particles filtered and removed by the filter surface 41 remain in processing filter 40, which, for this purpose, is preferably provided with a fully replaceable filter insert and can be replaced with a new filter insert, as has already been mentioned.

[0020] If the three units in the housing 11 become completely clogged and fail to allow sufficient fluid flow of the filtrate, an overflow unit 70, comprising an overflow valve 71 and a filter element 72 connected downstream thereto as a bypass, is assigned to protect the circuit and consumer 1. The valve 71 preferably opens when a preset differential pressure is exceeded, although this may also be controllable.

[0021] Figure 3 shows a slightly modified circuit. Components that are functionally identical to those in the preceding exemplary embodiment are given a reference numeral increased by 100. The consumer 101 and the fluid tank 102 are designed separately and connected to each other via line 180. A pump 190 for increasing the pressure for the consumer and the filtration device 110 connected upstream thereof is located in the supply line 103 between the fluid tank 102 and the inlet 112 of the housing 111 of the filtration device 110. The fluid then flows, firstly, into a backflowable main filter unit 120 equipped with a backflow element, and the filtrate obtained at the main filter surface 121 is supplied to the consumer, while the backflow fluid is supplied to an auxiliary filter unit 130, which is operated at intervals and can be backflowed, as already described, similarly but only at intervals by operating a valve 160 located in the housing 111 via an external control device 195 of the present invention. Here, the clean fluid obtained on the auxiliary filter surface 131 of the auxiliary filter unit 130 flows into the fluid tank 102 via line 116. However, when valve 160 is opened, the filthy fluid generated during the backflow on the auxiliary filter surface 131 enters the treatment unit 140, where the filthy particles are retained, and only the outflow fluid flow returns to the fluid tank 102 as treated (clean) fluid via line 119.

[0022] Figure 4 shows the structure and dimensions of the individual units within the filtration device 210, and reference numerals are again used here increased by 100 for functionally identical components compared to the two preceding exemplary embodiments. As can be clearly seen, the main filter unit 220 with the largest dimensions and the auxiliary filter unit 230 with significantly smaller dimensions and the processing unit with similar dimensions are located within the same housing 211. The housing 211 has a flange 291 as a connecting piece, and the entire filtration device 210 can be flanged to the engine via the flange 291, through which, for example, the filtrate obtained in the filtration device 210 can be supplied to the engine. The main filter unit 220 has a support body 225, which is cylindrical and has a slit-shaped passage or a recess of a suitable shape, surrounding it as the main filter surface 221, and inside the support body 225 is a backflow element 227 which can be rotated about the axis of a central flushing line 224, and this backflow element moves beyond the interior of the support body 225 with a flushing head 223 and partially cleans the filter surface 221 only in the area of ​​the flushing head 229. In the case of a pleated filter material with many folds, one of the folds may be assigned to a corresponding breakthrough in the support body in order to clean each individual fold of the filter means in a directed manner. The pleated filter material ensures a filter surface that is enlarged relative to the diameter of the support body 225. More than 90% of the total filter surface is therefore permanently available for filtration, and at the same time, a relatively large amount of backflow occurs in the area of ​​the flushing head 223, which is as is basically known to those skilled in the art with regard to the structure of the corresponding automatic filter, and this is why the structure is not further described here. The central backflow line 224 of the backflow element 227 opens into the interior of the auxiliary filter unit 230 via an internal line guide not shown, which has a structure that is basically very similar to that of the main filter unit 220, but is significantly smaller in size, and correspondingly has a smaller volume and also a correspondingly smaller dimensional filter surface.The auxiliary filter unit also has a support body 235 and a corrugated filter medium 236 supported on the circumference of the support body 235. The support body 235 is provided with a recess, such as the auxiliary filter surface 221. Inside the support body 235, a backflow element 237 is provided which can be rotated about the central dirt line 234 and has a flushing head 233 in order to cause the filter medium 236 to flow back. Here too, the flushing head 233 acts only partially on the partial surface of the filter medium 236, which is why most of the auxiliary filter surface 231 is always available for filtration.

[0023] The waste fluid accumulating via the flushing head 233 and the flushing line 234 in the auxiliary filter unit 230, which is more concentrated than the backflow fluid in the main filter unit 220, preferably flows from above into the processing unit 240 via an internal line, not shown here either. This has a filter insert with a cylindrical support body 245 provided with a recess, which in this case is also surrounded by a corrugated filter medium 246, forming the actual filter surface 241 of the processing unit 240. The filter medium 246 preferably extends cylindrically above the closed base 242 such that a replaceable filter insert, which can be completely replaced, is within the processing unit 240. If the inflow from above is only temporary, the processing unit 240 can form a sedimentation space with the filter insert, whereby individual dirt particles are deposited above the base 242, while the fluid passing through the filter medium 246 can be returned again as filtered fluid to the actual circuit.

[0024] The present invention is not limited to the aforementioned embodiments of the filtration system. Individual features of each embodiment may also be combined with one another, even if they are not explicitly mentioned with reference to the drawings. Individual elements may be omitted without departing from the scope of protection and the disclosure of the application, unless they have a direct functional relationship with other individual elements. The backflow elements or backflow members shown in the drawings are merely illustrative designs. Other designs and modes of operation may also be used for filter elements that can backflow within the housing. The processing unit 240 may also have a larger volume than the auxiliary filter unit to better utilize sedimentation. The use of pleated filter media to form the filter surface in all three units constitutes a preferred design, but individual or all units may also have other filter media or filter surfaces.

Claims

1. A filtration device for fluids, A filter housing (11) having a fluid inlet, A main filter unit (20) is provided with a rotatable backflow element located in the filter housing (11), A filtrate outlet for the filtrate filtered on the main filter surface (21) of the main filter unit, The system includes an auxiliary filter unit (30) for processing the backflow fluid that accumulates during the backflow on the surface of the main filter unit of the main filter unit, The backflow element is in a filtration device that enables continuous partial backflow of a portion surface (21) of the main filter surface (21) of the main filter unit for permanent partial cleaning of the main filter surface (21) by the backflow, The auxiliary filter unit (30) is integrated with the main filter unit (20) in the filter housing (11) of the main filter unit (20), and is connected to the outlet of the backflow fluid of the main filter unit. It is also provided with a backflow member that can operate to allow backflow at intervals in order to partially clean the filter surface (31) of the auxiliary filter unit (30) at intervals. A processing unit (40) for processing the filthy fluid that accumulates during the backflow of the filter surface (31) of the auxiliary filter unit (30) is connected downstream of the backflow member of the auxiliary filter unit (30), A filtration device characterized by the following:

2. The filtration device according to claim 1, characterized in that the processing unit (40) is integrated with the main filter unit (20) and the auxiliary filter unit (30) in the filter housing (11).

3. The filtration device according to claim 1, characterized in that the backflow element (227) for the main filter unit is connected to an internal flushing fluid line (224) in the filter housing (11) that opens to the inlet of the auxiliary filter unit (30).

4. The backflow member (237) of the auxiliary filter unit (30; 130; 230) is rotatable at intervals, The filtration device according to any one of claims 1 to 3, characterized in that the backflow member is connected to a fluid line in the filter housing (11; 111; 211) which is open at the inlet of the processing unit.

5. The filtration device according to any one of claims 1 to 3, characterized in that the filter housing (211) is a flange (291) thereby enabling the filtration device to be directly connected to a consumer as a unit.

6. The processing unit (240) has either a single replaceable filter insert or a double filter with a filter insert that is not backflow-proof, and / or The processing unit has a sedimentation space comprising a closed base (242) and a filter material (246) that can flow from the inside to the outside and is positioned above the base (242) to form a filter surface. The filtration device according to claim 1, characterized by the above.

7. The filtration device according to claim 6, characterized in that the processing unit (240) allows inflow into the sedimentation space from above, and the filter insert forming the sedimentation space is replaceable.

8. The filtration device according to any one of claims 1 to 3, 6, and 7, characterized in that the main filter unit (40) is provided with an overflow valve (71) as a bypass fixed by a filter element (72).

9. A filtration device according to any one of claims 1 to 3, 6 and 7, characterized in that a controllable valve (60; 160) switchable by a control device is connected between the auxiliary filter unit and the processing unit, and the backflow member for the auxiliary filter unit is active only when the valve (60; 160) is open.

10. A filter circuit comprising at least one consumer (1) to which a fluid as fuel or lubricant can be supplied, a fluid tank (2), and a filtration device (10; 110; 210) disposed between the fluid tank (2) and the consumer (1) in the circuit, A filter circuit characterized in that the filtration device is designed as described in claim 1.

11. The filter circuit according to claim 10, characterized in that the filtrate outlet behind the main filter unit is connectable to or connected to a consumer (101), and the clean fluid outlet behind the auxiliary filter unit and the fluid outlet behind the processing unit are connected to a storage tank (102) for the fluid, and the consumer is also connected to the fluid tank by a discharge line (180) for the fluid.

12. The filter circuit according to claim 10 or 11, characterized in that a main pump (190) is connected between the fluid tank and the filtration device.

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