Title of Invention

FLUID FILTER

Abstract

The invention relates to a fluid filter, in particular an oil filter for an internal combustion engine, comprising a cup-shaped housing having a fluid inlet and a fluid outlet, a filter element being arranged with a seal between the inlet and outlet, a one-piece barrier membrane being arranged in the area of the opening of the cup-shaped housing and whereby the fluid inlet and/or the fluid outlet can be closed by the barrier membrane.

Full Text

FORM 2 THE PATENT ACT 1970 (39 of 1970) The Patents Rules, 2003 COMPLETE SPECIFICATION (See Section 10, and rule 13) 1. TITLE OF INVENTION FLUID FILTER 2. APPLICANT(S) a) Name b) Nationality c) Address MANN+HUMMEL GMBH GERMAN Company ABTEILUNG VR-P D-71636 LUDWIGSBURG GERMANY 3. PREAMBLE TO THE DESCRIPTION The following specification particularly describes invention and the manner in which it is to be performed Fluid Filter Description The invention relates to a fluid filter according to the preamble of Patent Claim 1. State of the Art Fluid filters known in the state of the art very often have barrier membranes and non-return valves to prevent fluid from flowing back out of the filter when the internal combustion engine is stopped while also preventing the fluid from flowing out of the filter when the filter is replaced. German Patent DE 4140140 Al describes a screw-on filter for fluids, in particular a lubricant oil filter for an internal combustion engine. Such a filter has a peripheral barrier membrane in the area of the fluid inlet which achieves the sealing function via a peripheral lip which has a sealing fit on a cover plate of the replaceable filter. In addition, a non-return valve consisting of a cage, a spring arranged in the cage, and a valve body acted upon by the spring with spring force is mounted centrally in the interior of the filter medium, a sealing fit being established between the valve body and the cage. However, it is a disadvantage here that many different parts are needed for the functioning of the non-return valve and the barrier membrane, and these parts are manufactured from different materials. The object of the present invention is to create a fluid filter which offers an improvement over the known state of the art due to the fact that the complexity of the design and of the combination of the barrier membrane and the non-return valve is reduced. This object is achieved through the features of Patent Claim 1. 2 Advantages of the Invention The inventive fluid filter, in particular an oil filter for an internal combustion engine, has a cup-shaped housing having a fluid inlet and a fluid outlet, a filter element being arranged with a seal between the inlet and outlet. A one-piece barrier membrane is situated in the area of the opening in the cup-shaped housing, where the fluid inlet and/or the fluid outlet can be closed by the barrier membrane. The following options exist here: • when the filter is inserted and the internal combustion engine is running, the inlet and outlet are opened by the barrier membrane; • when the internal combustion engine is stopped and the filter element is inserted, either the inlet and outlet are closed or only the inlet is closed, and • when the filter is removed, the inlet and outlet are again closed. The fluid filter may be designed as a spin-on filter or as an oil module. The housing may be made of a metallic material or plastic and the filter element may be made of filter paper or a synthetic material having accordion pleating, coils or alternately sealed channels with through-flow at the end. This results in an extremely space-saving embodiment of the non-return valve as a membrane and the filter may have a very compact design. In addition, the membrane can be manufactured much less expensively and more easily than a spring-loaded basket valve. Such a filter may be used when there are fluids in the area of an internal combustion engine, such as oil, fuel or water. However, applications outside of internal combustion engines, e.g., in water processing systems, are also conceivable. According to an advantageous embodiment of this invention, the filter element is in the form of a hollow cylinder having an end disk at least in the area of the opening in the cup-shaped housing, whereby the barrier membrane has a 3 detachable or non-detachable connection to the end disk. The connection may be established by gluing, welding or by other non-detachable joining methods known from the state of the art. This has the advantage that, among other things, each time the filter element is changed, the barrier membrane is also replaced and therefore there is no decline in barrier function over the entire lifetime of the fluid system. According to an alternative embodiment of this invention, the barrier membrane is detachably or non-detachably connected to a cover plate of the filter accordingly. The cover plate in the case of a spin-on filter may be understood to be, for example, the hollow cylindrical closure on the cup-shaped housing which the connecting means has for joining to a connecting head. In addition, the cover plate may be a component located in the area of the connection between the filter element and a connecting head independently of end disks present on the filter element. As an alternative, it is also possible for the barrier membrane to be detachably or non-detachably joined to a supporting pipe accordingly. In a plurality of applications, it is self-evident in the case of filter elements designed as a hollow cylinder to provide a supporting pipe in the interior of the filter element to prevent the filter element from collapsing when there are pressure pulsations. The barrier membrane can be joined to the supporting pipe accordingly via a detachable or non-detachable connecting method. The non-detachable connecting methods, as described above, may of course also be used for all three alternative embodiments. In the case of the detachable joining methods, the possibilities of designing the connection to be detachable in a non-destructive manner by means of a joining method or a clipping method or a clamping method, for example, are also applicable for all three embodiments. According to an advantageous embodiment of the present invention, the barrier membrane is made of a thermoplastic elastomer (TPE). This choice of materials yields the advantage of making it possible to work with a flexible membrane having an inherent elasticity. This membrane can be manufactured easily and inexpensively by the injection molding method and can be adapted to the 4 prevailing pressure conditions by a slight change in the composition of the plastic or through design measures. As an alternative to this, the barrier membrane may also be made of a two-component adhesive, where the softer component is used for the sealing function and the harder component is used for the connecting contour to the end disk, the cover plate or the barrier membrane. It is advantageous if the barrier membrane has a circular connecting plate, a first barrier being arranged on its outer edge. In addition, the connecting plate has the second barrier arranged concentrically in the area on the inside radially. The first barrier may be designed, for example, as a flexible elastic sealing face arranged at an angle to the connecting plate, and the second barrier may be designed as a flexible tube continuation from the circular connecting plate, whereby the tube has the shape of a duckbill toward the end and therefore establishes the sealing function. According to another embodiment of the present invention, the connecting plate has means for detachable connection to an end disk of the filter element of the cover plate or the supporting body. This may be accomplished through passages which are joined to special contours of the end disk, the cover plate or the supporting body or via a clip or catch connection, for example. In the return flow barrier state, i.e., in the sealing state, the first return flow barrier is advantageously in sealing contact with a sealing contour arranged concentrically on the outside radially. The sealing contour here may be formed, for example, by another end disk, a sealing contour formed from the housing or a sealing contour formed from a cover plate on the filter. The function of the barrier membrane and non-return valve from the state of the art is thus taken over and greatly simplified by using a one-piece barrier membrane. This results in great cost savings and optimum utilization of design space. 5 These and other features of preferred refinements of the present invention are also derived from the description and the drawings in addition to the claims, whereby individual features may be implemented alone or several may be combined in the form of subcombinations in the embodiment of the present invention and also in other fields and may constitute advantageous and independently patentable embodiments for which patent protection is herewith claimed. Drawing Additional details of the present invention are illustrated in the drawing and described below with reference to schematic exemplary embodiments. FIG 1 shows a sectional diagram of the fluid system, FIG 2 shows a section through the filter element and the cup-shaped housing, FIG 3 shows an isometric view of the filter element and the cup-shaped housing, FIG 4 shows a single isometric view of the cup-shaped housing, FIG 5 shows a section through the outer shell of the filter element, FIG 6 shows an isometric view of the barrier membrane, FIG 7 shows a top view of the section in the area of the blocking means, FIG 8 shows a section through an alternative barrier membrane and FIG 9 shows a section through a part of an alternative filter element. Embodiments of the Invention FIG 1 shows a sectional diagram of a fluid filter system 10, where a cup-shaped housing 11 is connected by a bayonet connection to a connecting head 12. The connecting head may be a separate connecting flange or it may be formed directly from a component of an internal combustion engine. The filter system may 6 be used for fluids of any type associated with an internal combustion engine, such as oils, fuels, hydraulic fluids or coolants. An inlet 13 and an outlet 14 are provided in the connecting head 12 of the filter system 10. The outlet 14 is arranged concentrically at the center of the connection between the cup-shaped housing 11 and the connecting head 12, and the inlet 13 is arranged concentrically around the outlet 14, likewise being arranged in the interior of the connection between the cup-shaped housing 11 and the connecting head 12. A filter element 15 is arranged in the cup-shaped housing 11. The filter element 15 here has a canister 16 which holds the filter medium or media. The canister 16 is supported on the periphery radially toward the outside on an inside wall 17 of the cup-shaped housing 11 and at the same time is supported by grooves on an outside wall 18 of a first filter bellows 19 provided in the canister 16. The canister 16 is designed to be fluid-tight and also has the function of an outer supporting pipe for a first filter bellows and a support with respect to pressure pulsations on the cup-shaped housing 11. The canister 16 may therefore be designed to have a relatively small material thickness because it is actually supported on the cup-shaped housing 11, depending on the pressure pulsation. A supporting pipe 20 is arranged concentrically in the interior of the filter element with a second filter bellows 21 extending around the supporting pipe. The first and second filter bellows may be formed by a filter medium having zigzag pleating, by a coiled filter medium, a combination of the two or some other filter bellows known from the state of the art. In the area of the housing bottom 22 of the canister 16, the two filter bellows are held by an end disk 23 designed in the form of a circular ring with a concentric opening 24. A spring element 25 is formed in one piece from the end disk 23, supporting the filter bellows on the housing bottom 22 and secured and fixed axially by applying a spring force acting axially upward. The axial securing and fixation are accomplished through the inside contour of the canister 16. On the opposite end of the filter bellows, the first filter bellows 19 have an end disk seal 26. The second filter bellows 21 arranged in the interior of the first filter bellows 19 have a slightly higher axial extent than the first filter bellows 19, and the end closure of the second filter bellows 21 is accomplished via an end disk 27 having a circular shape forming a concentric passage for the outlet 14. The end disk 7 27 has a fastening contour 28 for a barrier membrane 29 axially in the direction of the connecting head 12. The fastening contour 28 is distributed over the end disk 27 and has a plurality of pins or mushroom-shaped contours protruding axially in the direction of the connecting head 12. The barrier membrane 29 is fastened tightly onto the end disk 27 by means of the fastening contour 28, sealing the fluid inlet 13 on the one hand when the internal combustion engine is stopped and also in the event of maintenance sealing the fluid outlet 14. The barrier membrane 29 is preferably made of a soft thermoplastic material such as a thermoplastic elastomer (TPE). The end disk 26 has a ring collar 30 protruding axially and concentrically, a groove being arranged on the outer circumference to accommodate a sealing ring 31. The ring collar 30 is inserted into a collar receptacle 32 of the connecting head when the cup-shaped housing 11 and the connecting body 12 are joined, where the sealing ring 31 serves to provide a seal between the ring collar 30 and the collar receptacle 32 there. An outlet pipe 33, which is inserted into the opening of the end disk 27 and opens the return flow barrier of the barrier membrane 29 on the outlet side there, is situated concentrically in the interior of the collar receptacle 32. To provide a seal between the raw side and the clean side, the gasket here is arranged radially between the barrier membrane 29 and the outlet pipe 33, which is in turn situated in the connecting head 12. For a fluid-tight seal of the filter element 15, the canister 16 and the end disk 26 are non-detachably joined with a seal via a connecting contour 34, e.g., by a welding method or an adhesive bonding method. To release the housing for the purpose of maintenance and for connecting it, the cup-shaped housing 11 has a tool receptacle 35 which may have a hexagon socket or a hexagon insert bit. To perform maintenance, a tool is placed here to separate the cup-shaped housing 11 from the connecting head 12 or to reattach the two parts again. From the one axial end of the canister 16, several parts 36 of catch elements are1 designed in the form of noses protruding radially outward and distributed over the circumference. These engage in recesses in the cup-shaped housing and recesses 8 within a catch contour of the cup-shaped housing 11 which are shown in the following figures. At the same time, the part 36 of the catch elements of the canister 16 also functions as a connecting contour 34 to the end disk 26. The connecting head 12 has guides 37 in which catch contours, formed from the parts 36 of the catch elements of the canister 16 and from the cup-shaped housing 11, can be inserted and guided. At least one blocking means 38 is provided in the outer area of the connecting head 12, preventing a connection between the cup-shaped housing and the connecting head 12 when no filter element 15 is inserted or when the wrong filter element has been inserted. The blocking means 38 here engage in a recess 44 in the cup-shaped housing 11 and thus prevent the bayonet closure from closing. FIG 7 shows the function of the blocking means 38. The fluid to be cleaned flows through the inlet 13 of the connecting head 12 into an intermediate space 39 between the two filter bellows 19, 21, flowing through the inner second filter bellows 21 in [sic; into?] an outflow space 40 on the clean side within the supporting pipe 20, then flowing back through the barrier membrane 29 opened by the outlet tube 33 through the outlet 14 on the clean side back into the system. Another part of the fluid that has not yet been cleaned flows through, starting from the intermediate space 39, the outer first filter bellows 19 radially outward into a volume on the canister end in which it flows downward to the housing bottom 22 and from there can be returned back to the system through the outlet 14 on the clean side. FIG 2 shows the combination of filter element 15 and cup-shaped housing 11 in a sectional view. The components corresponding to the previous figure are labeled with the same reference notation. It can be seen here that with the cup-shaped housing 11 including the filter element 15 detached from the connecting head 12, the barrier membrane 29 has reverted back to its original shape in the area of the outlet 14 on the clean side due to the outlet tube 33 which is no longer present, and outflow of the fluids stored in the filter element 15 is prevented. Due to the design of the barrier membrane 29 as a thermoplastic elastomer, a restoring force can be induced 9 within the barrier membrane due to the contour, as manifested in a seal on the outlet end which is tightly sealed by the restoring force alone. FIG 3 shows an isometric view of the cup-shaped housing 11 with the filter element 15 arranged in it. Components corresponding to the previous figures are labeled with the same reference notation. The multiple fastening contours 28 of the end disk 27 for the barrier membrane 29 can be seen clearly here. In addition, several catch contours 42 for producing the bayonet closure are arranged on the periphery in a uniform distribution inside the filter system 10 on the open axial end of the cup-shaped housing 11. When the filter element 15 is installed correctly, the parts 36 of the catch element near the filter element are arranged in a recess 43 on the catch contour 42, thereby completing the catch contour 42. When the filter element 15 is not inserted or the filter element that has been inserted does not fit properly, the recess 43 remains free within the catch contour 42, a bayonet-type connection between the cup-shaped housing 11 and the connecting head 12 being prevented by the blocking means 38. The blocking means 38 then engages in the recess 43 and thereby prevents rotation of the cup-shaped housing 11 in relation to the connecting head 12. FIG 4 shows the cup-shaped housing 11 in an isometric view. The cup-shaped housing 11 has recesses 44 emanating axially from the open end of the cup-shaped housing 11 distributed over the circumference for insertion of the filter element 15 and ending in the recesses 43 for the catch contour. The filter element 15 with the parts 36 of the catch elements is therefore inserted into the recess 44 and inserted to the end of the recess 43 until completing the catch contour 42. Only in this way are the catch contours 42 completed for the connection to the connecting head 12. FIG 5 shows a section through the canister 16, which forms the outside shell of the filter element 15. Several grooves 45 are distributed over the lateral surface of the canister 16, forming a contact surface 46 for the first filter bellows 19 in the interior of the canister 16. Since the grooves 45 are not arranged continuously in the inside circumference of the canister 16, this yields a simple possibility for supplying 10 the fluid, which flows through the first filter bellows 19 after being cleaned, to the outflow space 40 on the clean side via the housing, i.e., the canister bottom 22. Then the remainder of the filter element described above is inserted into the canister 16 and connected to the canister 16 on the connecting contour 34. This results in a fluid-tight system which, whenever, maintenance is required, ensures that soiling of the environment and the surroundings is prevented, as can dirty fingers2 of the maintenance person. The axial closure of the canister 16 in the area of the open end is in turn formed by the parts 36 of the catch elements which engage in the recess 43 of the catch contour 42 of the cup-shaped housing 11. FIG 6 shows the barrier membrane of an isometric view. The components corresponding to the previous figures are labeled with the same reference notation. The barrier membrane is designed essentially in the form of a sheet, preferably a thermoplastic elastomer, and has several openings 47 in the sheet-like part to establish the connection with the end disk 27 via the fastening contour 28. The outer area of the barrier membrane 29 has a sealing surface 48 which is angled in relation to the sheet-like area for the inlet area of the filter system 10 which, due to the flexibility of the material, is separated from the sealing surface in the sealing end disk 26 when the fluid to be cleaned is flowing in, thereby ensuring an influx of the fluid. When the internal combustion engine is not running, i.e., when there is no liquid pressure applied to the barrier membrane, the sealing surface 48 seals the inlet 13 due to its elasticity. Concentrically in the interior of the barrier membrane 29, a type of sealing valve 49 is provided for sealing the outlet when the filter element is removed from the fluid cycle. The outlet gasket 49 has a type of duckbill, which, in the inserted state, is opened from the connecting head 12 through the outlet tube 33; this outlet gasket closes again due to its own elasticity on removal of the outlet tube 33. Thus the barrier membrane and the non-return valve are implemented here in one piece in one component. 11 FIG 7 illustrates one possibility for using the blocking means 38. The components corresponding to those in the previous figures are labeled with the same reference notation. FIG 7 shows a top view of a section in the area of the blocking means 38. The blocking means 38 is arranged in the connecting head 12, with a locking pin 50 and a spring means 51 being arranged in the connecting head 12 so that the locking pin 50 is movable axially against the force of the spring means 51 and engages in the recess of the catch contour 43 due to the force of the spring means 51 when the cup-shaped housing 11 and the connecting head 12 are brought together when the filter element 15 is not present or provided, thereby preventing rotation to establish the bayonet connection. When the filter element 15 is correctly inserted, the recesses 43 and 44 are filled by the parts 36 of the catch elements of the filter element 15 and thus complete the catch contour 42 so that the locking pin 50 is pressed into the connecting head 12 against the force of the spring means 51 and it is therefore possible for the cup-shaped housing 11 to be rotated with respect to the connecting head 12, thus making it possible for a bayonet connection to be established. FIG 8 shows a section through an alternative barrier membrane 29. The components corresponding to those in the preceding figures are labeled with the same reference notation. The fastening with the filter element is implemented here via a peripheral ring groove 52 arranged concentrically with the inlet sealing surface 48. This then serves to accommodate an end disk (not shown here), and this connection is illustrated in the following figure. FIG 9 shows a section through a part of an alternative filter element using the barrier membrane 29. The components corresponding to those in the previous figures are labeled with the same reference notation. The inner filter bellows 21 is connected here to the lower end disk 23 and the upper end disk 27 by a butt welding method. The end disk closure 26 has a fastening ring 53 arranged concentrically, holding the barrier membrane 29 by means of the fastening ring 53. The fastening ring 53 is preferably connected in one piece to the end disk closure 26 via connecting webs 55, whereby the connecting webs 55 are arranged on the periphery around the 12 outlet 14. End disk closure 26 and end disk 23 each have sealing seats 54 for the outer filter bellows 19 and also secure it. The canister 16 (not shown here) may be designed similarly to the previous description and thus connects the two end disks 23 and 26. 13 We Claim 1. Fluid filter, in particular an oil filter for an internal combustion engine, having a cup-shaped housing with a fluid inlet and a fluid outlet, whereby a filter element is arranged with a seal between the inlet and outlet, characterized in that a one-piece barrier membrane is situated in the area of the opening of the cup-shaped housing, so that the barrier membrane of the fluid inlet and/or the fluid outlet can be closed. 2. Fluid filter as claimed in Claim 1, characterized in that the filter element has a hollow cylindrical shape and has an end disk at least in the area of the opening of the cup-shaped housing and the barrier membrane is detachably or non-detachably joined to the end disk. 3. Fluid filter as claimed in Claim 1, characterized in that the barrier membrane is detachably or non-detachably connected to a cover plate of the filter accordingly. 4. Fluid filter as claimed in Claim 1, characterized in that the barrier membrane is detachably or non-detachably attached to a supporting pipe of the filter accordingly. 5. Fluid filter as claimed in any one of preceding claims, characterized in that the barrier membrane is formed from a thermoplastic material, in particular a TPE. 6. Fluid filter as claimed in any one of Claims 1 through 4, characterized in that the barrier membrane is made of a two-component plastic. 7. Fluid filter as claimed in any one of the preceding claims, characterized in that the barrier membrane has a circular connecting plate; a first return flow barrier is situated on its outer edge and the connecting plate has a second return flow barrier arranged concentrically in the inside area radially. 14 8. Fluid filter as claimed in Claim 7, characterized in that the connecting plate has means for detachable connection to an end disk of the filter element or to a cover plate. 9. Fluid filter as claimed in any one of Claims 7 through 8, characterized in that the first return flow barrier in the return flow barrier state is in sealing contact with a sealing contour arranged concentrically thereto and on the outside radially. 15 Abstract The invention relates to a fluid filter, in particular an oil filter for an internal combustion engine, comprising a cup-shaped housing having a fluid inlet and a fluid outlet, a filter element being arranged with a seal between the inlet and outlet, a one-piece barrier membrane being arranged in the area of the opening of the cup-shaped housing and whereby the fluid inlet and/or the fluid outlet can be closed by the barrier membrane. FIG1 To The Controller of Patent The Patent Office Mumbai 16

Documents:

215-mum-2006-abstract(granted)-(26-2-2009).pdf

215-mum-2006-abstract.doc

215-mum-2006-abstract.pdf

215-MUM-2006-CANCELLED PAGES(6-2-2009).pdf

215-mum-2006-claims(granted)-(26-2-2009).pdf

215-mum-2006-claims.doc

215-mum-2006-claims.pdf

215-MUM-2006-CORRESPONDENCE(6-2-2009).pdf

215-MUM-2006-CORRESPONDENCE(IPO)-(24-3-2009).pdf

215-mum-2006-correspondence-received-ver-120406.pdf

215-mum-2006-correspondence-received-ver-150206.pdf

215-mum-2006-correspondence-received-ver-270406.pdf

215-mum-2006-correspondence-received.pdf

215-mum-2006-description (complete).pdf

215-mum-2006-description(granted)-(26-2-2009).pdf

215-MUM-2006-DRAWING(AMENDED)-(6-2-2009).pdf

215-mum-2006-drawing(granted)-(26-2-2009).pdf

215-mum-2006-drawings.pdf

215-MUM-2006-ENGLISH TRANSLATION(6-2-2009).pdf

215-MUM-2006-FORM 1(27-4-2006).pdf

215-MUM-2006-FORM 18(16-2-2006).pdf

215-MUM-2006-FORM 18(20-12-2006).pdf

215-MUM-2006-FORM 18(6-2-2009).pdf

215-mum-2006-form 2(granted)-(26-2-2009).pdf

215-MUM-2006-FORM 2(TITLE PAGE)-(15-2-2006).pdf

215-mum-2006-form 2(title page)-(granted)-(26-2-2009).pdf

215-mum-2006-form-1.pdf

215-mum-2006-form-2.doc

215-mum-2006-form-2.pdf

215-mum-2006-form-26.pdf

215-mum-2006-form-3.pdf

215-mum-2006-form-5.pdf

215-MUM-2006-SPECIFICATION(AMENDED)-(6-2-2009).pdf

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