Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D39/00—Filtering material for liquid or gaseous fluids
  • B01D39/14—Other self-supporting filtering material ; Other filtering material
  • B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D39/00—Filtering material for liquid or gaseous fluids
  • B01D39/14—Other self-supporting filtering material ; Other filtering material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D39/00—Filtering material for liquid or gaseous fluids
  • B01D39/14—Other self-supporting filtering material ; Other filtering material
  • B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
  • B01D39/1607—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous
  • B01D39/1623—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous of synthetic origin
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/001—Combinations of extrusion moulding with other shaping operations
  • B29C48/0017—Combinations of extrusion moulding with other shaping operations combined with blow-moulding or thermoforming
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
  • B01D2239/06—Filter cloth, e.g. knitted, woven non-woven; self-supported material
  • B01D2239/069—Special geometry of layers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
  • B01D2239/10—Filtering material manufacturing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
  • B01D2239/12—Special parameters characterising the filtering material
  • B01D2239/1233—Fibre diameter

Definitions

• Air filter medium with two mechanisms of action
• the invention relates to an air filter medium in the form of a layered nonwoven material.
• Such filter media are used in filters, for example in room air filters and air conditioning systems, but especially in air filters for the motor vehicle interior or for engines.
• the filter media are prepared in a melt-spin process such as a spunbond process or a melt-blown process as described in e.g. is described in DE 41 23 122 A1.
• the intake air of internal combustion engines for example in motor vehicles or in the off-highway region is usually filtered to protect the engine combustion chamber from mechanical damage by sucked particles from the ambient air.
• An important criterion in the design of the filter elements is to ensure a long service life of the filter with simultaneously high separation efficiency of the sucked particles.
• Motor vehicles have a precisely calculated power distribution system.
• the heating / ventilation / air conditioning area has only limited energy available. Also, the cost of vehicle components may only be within a narrow range.
• car buyers are increasingly demanding more comfort and safety.
• Particle filters with a pressure drop or differential pressure which is as low as possible are of particular importance in this respect, since only a low pressure has to be generated by the fan motor and the energy consumption is thus low. Furthermore, this works quieter due to the lower power required, which reduces the noise and thus significantly increases ride comfort.
• the demand for filter systems with low differential pressure competes with the demanded separation efficiency and the required service life, ie the time expressed in mileage, that a filter can remain in the vehicle until it has to be replaced.
• pollen filters that only filter pollen from the incoming air in the vehicle are not sufficient for the vehicle interior.
• the allergens to which the immune system of allergic persons react are proteins whose diameter is only a fraction of the pollen diameter. They are in the size range around 0.1 pm, that is, the area that has the biggest problems for particulate filters, the so-called MPPS (Most penetrating particle size). Accordingly, the separation efficiency should be at least 50% in this size range, this being measured by means of an aerosol whose particles have approximately the same density, for example NaCl. At the same time with such filters when installed in motor vehicles life of at least 30 000 kilometers can be achieved.
• EP 1 198 279 B1 discloses a meltblown nonwoven structure which consists of at least two layers, one layer consisting of microfibers while the other layer consists of macrofibres. The layers are deposited on each other and adhere to each other by connections between the fibers. However, if nonwoven structures of this type are used in the field of air filtration, they are very rapidly absorbed due to the particles present in the air. Basically, a distinction is made between two filter types or filter processes.
• Depth filters are more likely to have open-pored fiber material that absorbs the debris over the entire depth of the medium. Often this is constructed in three dimensions, ie on the upstream side coarse, downstream fine fiber diameters can be found. The Dirt particles enter the medium and are stopped and stored in front of the fine fiber layer. The pressure loss of this filter medium increases only slowly. However, a cleaning is not possible because the dirt particles are firmly embedded in the open-pore fiber material.
• Air filter medium according to the invention is any type of material which is suitable for the purification of air.
• a melt-spinning process in the context of the invention is any process in which a web of starting materials is formed by depositing the processed starting materials on a substrate.
• the starting materials are processed in this case in particular by spraying from nozzles in the molten state.
• Regenerable within the meaning of the invention means that a filter medium can be at least partially cleaned by a work step and ideally is returned to the initial state. This can be achieved for example by an air recoil, a suction, a burning and / or a mechanical knocking. In particular, in this case filtered particles are removed from the filter medium or shifted so that the air resistance of the filter medium decreases.
• Open-pore in the sense of the invention means that the filter medium has pores that are not closed, that is, in which the chambers, which are formed by pores in combination. The thickness in the sense of the invention is determined perpendicular to the surface of the filter material.
• In the direction of the air flow to be filtered in the sense of the invention means in the direction of the inflow side to the downstream side of the filter medium.
• Differential pressure in the context of the invention is the pressure decrease of an air flow when flowing through a filter or filter medium.
• the filter medium By combining a depth filter component with a surface filter component, the filter medium has, on the one hand, a high absorption capacity for particles which are stored in the depth filter portion, and, on the other hand, the surface filter portion can be regenerated.
• a filter medium which has a long life, i. the slowest possible increase of the differential pressure, and at the same time provides the possibility of at least partial regeneration of the filter medium.
• the service life compared to a pure depth filter is significantly extended and extended the time intervals between necessary regenerations by air surges against a pure surface filter.
• the air filter medium has a regular three-dimensional macrostructure, which preferably consists of four- or six-sided pyramids, cones, vaults, corrugations or cracks.
• a three-dimensional macrostructure in the sense of the invention is any type of structure that is located on the surface of the filter medium.
• Macrostructure in the sense of the invention is a structure that is visually without auxiliary center and / or at least tactile perceptible.
• the coexistence of the depth filter component and the surface filter component on the upstream surface of the air filter material is realized by the macrostructure.
• the parts of the macrostructure of the filter may form the depth filter component while the surface filter component is arranged between the macrostructure.
• the macrostructure is attached to the inflow side of the filter medium.
• the inflow area of the filter medium increases the inflow area of the filter medium.
• the inflow area can be increased up to a multiple of the inflow area of a substantially planar material.
• the increase in the inflow area causes a reduction in the pressure loss or the differential pressure of the air stream flowing through or a reduction in the air resistance of the filter medium and / or the finished filter.
• the depth filter component is disposed on the surface filter component forming a continuous layer.
• a continuous layer according to the invention extends over the entire surface of the filter medium.
• the depth filter component constitutes 50 to 90%, preferably 50 to 70%, more preferably 70 to 90% of the surface of the web.
• Fig. 1 shows a cross section of a first embodiment of the filter medium according to the invention.
• Fig. 2 illustrates the deposition of particles in a filter medium according to the first embodiment.
• Fig. 3 illustrates the regenerated filter medium after an air recoil.
• FIG 4 shows a cross section through a second embodiment of the filter medium according to the invention.
• Fig. 5 shows a cross section through a third embodiment of the filter medium according to the invention.
• the filter medium according to the invention is formed from two constituents.
• depth filter components 1 are arranged alternately with surface filter constituents 2.
• the depth filter component 1 has at least upstream I, i.
• macrostructures On the side on which the air flow to be filtered arrives, macrostructures. These macrostructures can take any three-dimensional shape, which contributes to improving the filter performance.
• the depth filter component 1 is further distinguished by the fact that its fiber diameter vary over its cross section. Thus, on the upstream side I coarse, downstream II fine fiber diameters are arranged.
• the surface filter component 2 of the filter is located in the interstices of the macrostructures of the depth filter component 1 and predominantly has a fiber structure such that no particles penetrate into it.
• particles which are located in the air flow to be filtered are filtered by two mechanisms: Firstly, particles 3 to be filtered penetrate into the depth filter component 1 on the inflow side deposit in it. By varying the fiber diameter in the direction of air flow results in that first coarse particles 3 are filtered, whereas finer particles 3 penetrate further into the interior of the filter.
• particles 3 to be filtered are deposited on the surface filler component 2.
• the particles 3 penetrate this not or only slightly into the air filter medium and are therefore deposited on the surface as a filter cake, as shown in Fig. 2.
• the surface filter region 2 of a filter which comprises the filter medium according to the invention, is first added with particles 3 before the depth filter component 1 fills with particles 3.
• the filter can be further operated with an increase in the differential pressure due to the addition of the surface filter component 2, wherein the filtering effect is then largely on the depth filter component 1.
• This has a much higher absorption capacity for particles 3 than the surface filter constituent 2, since the particles 3 are storable in the three-dimensional structure.
• the user then has the possibility of regenerating the surface filter constituent 2 by means of an air repulsion, in which air is blown in the opposite direction of the normal air flow direction of the air flow to be filtered, and / or by sucking the particles 3 from the surface of the air filter medium.
• FIG. 3 illustrates an air filter medium regenerated in this way.
• the filter cakes on the surface filter component 2 are removed and only the particles 3 stored in the macrostructures of the depth filter component 1 remain in the filter.
• FIGS. 4 and 5 show alternative embodiments of the present invention. These differ from the first embodiment in the different shapes of the macrostructures.
• the macrostructures may both be arranged as isolated structures on the air filter medium or form a regular macrostructure.
• the macrostructures can be formed as rows or be arranged like a checkerboard or honeycomb.
• the macrostructures can serve as spacers to another layer of the air filter medium.
• the depth filter constituent 1 could also be arranged on the inflow side I on the surface filter constituent 2. It goes without saying that both the depth filter constituent 1 and the surface filter region 2 can consist of one or more layers which predominantly have different fiber diameters in each case.
• the air filter medium according to the invention is produced in a melt-spin process such as, for example, a spunbond process or a melt-blown process, wherein the depth filter region 1 with the macrostructures is formed by deep-drawing the nonwoven during the production process.
• a melt-spin process such as, for example, a spunbond process or a melt-blown process
• the depth filter region 1 with the macrostructures is formed by deep-drawing the nonwoven during the production process.
• a separate processing of the web is not necessary for this purpose.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Filtering Materials (AREA)
• Filtering Of Dispersed Particles In Gases (AREA)

Priority Applications (8)

Applications Claiming Priority (2)

Publications (2)

Family

ID=45094570

Family Applications (1)

Country Status (10)

Cited By (5)

Families Citing this family (7)

Citations (2)

Family Cites Families (104)

• 2010
  • 2010-11-22 DE DE102010052155A patent/DE102010052155A1/de active Pending
• 2011
  • 2011-11-21 US US13/988,554 patent/US9168471B2/en active Active
  • 2011-11-21 CN CN201180055987.1A patent/CN103237584B/zh not_active Expired - Fee Related
  • 2011-11-21 JP JP2013539172A patent/JP2014501607A/ja active Pending
  • 2011-11-21 BR BR112013012505A patent/BR112013012505A2/pt not_active Application Discontinuation
  • 2011-11-21 CA CA2818473A patent/CA2818473A1/en not_active Abandoned
  • 2011-11-21 MX MX2013005653A patent/MX2013005653A/es not_active Application Discontinuation
  • 2011-11-21 KR KR1020137016280A patent/KR20130132490A/ko not_active Withdrawn
  • 2011-11-21 WO PCT/EP2011/005854 patent/WO2012069172A2/de not_active Ceased
  • 2011-11-21 EP EP11791213.9A patent/EP2643272B1/de active Active

Patent Citations (2)

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