GB2223695A - Making radially pleated filter elements - Google Patents
Making radially pleated filter elements Download PDFInfo
- Publication number
- GB2223695A GB2223695A GB8823806A GB8823806A GB2223695A GB 2223695 A GB2223695 A GB 2223695A GB 8823806 A GB8823806 A GB 8823806A GB 8823806 A GB8823806 A GB 8823806A GB 2223695 A GB2223695 A GB 2223695A
- Authority
- GB
- United Kingdom
- Prior art keywords
- sheet
- hot melt
- pleated filter
- melt adhesive
- filter element
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000000853 adhesive Substances 0.000 claims abstract description 35
- 230000001070 adhesive effect Effects 0.000 claims abstract description 35
- 239000011324 bead Substances 0.000 claims abstract description 22
- 239000004831 Hot glue Substances 0.000 claims description 27
- 238000000034 method Methods 0.000 claims description 13
- 238000004519 manufacturing process Methods 0.000 claims description 10
- 239000003365 glass fiber Substances 0.000 abstract description 19
- 238000011144 upstream manufacturing Methods 0.000 abstract 1
- 239000000428 dust Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 description 1
- CYJRNFFLTBEQSQ-UHFFFAOYSA-N 8-(3-methyl-1-benzothiophen-5-yl)-N-(4-methylsulfonylpyridin-3-yl)quinoxalin-6-amine Chemical compound CS(=O)(=O)C1=C(C=NC=C1)NC=1C=C2N=CC=NC2=C(C=1)C=1C=CC2=C(C(=CS2)C)C=1 CYJRNFFLTBEQSQ-UHFFFAOYSA-N 0.000 description 1
- RSWGJHLUYNHPMX-UHFFFAOYSA-N Abietic-Saeure Natural products C12CCC(C(C)C)=CC2=CCC2C1(C)CCCC2(C)C(O)=O RSWGJHLUYNHPMX-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- KHPCPRHQVVSZAH-HUOMCSJISA-N Rosin Natural products O(C/C=C/c1ccccc1)[C@H]1[C@H](O)[C@@H](O)[C@@H](O)[C@@H](CO)O1 KHPCPRHQVVSZAH-HUOMCSJISA-N 0.000 description 1
- 230000002745 absorbent Effects 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- DQXBYHZEEUGOBF-UHFFFAOYSA-N but-3-enoic acid;ethene Chemical compound C=C.OC(=O)CC=C DQXBYHZEEUGOBF-UHFFFAOYSA-N 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- -1 ester hydrocarbon Chemical class 0.000 description 1
- 239000005038 ethylene vinyl acetate Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229920001568 phenolic resin Polymers 0.000 description 1
- 229920001200 poly(ethylene-vinyl acetate) Polymers 0.000 description 1
- 150000003505 terpenes Chemical class 0.000 description 1
- 235000007586 terpenes Nutrition 0.000 description 1
- KHPCPRHQVVSZAH-UHFFFAOYSA-N trans-cinnamyl beta-D-glucopyranoside Natural products OC1C(O)C(O)C(CO)OC1OCC=CC1=CC=CC=C1 KHPCPRHQVVSZAH-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- 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
- B01D46/52—Particle separators, e.g. dust precipitators, using filters embodying folded corrugated or wound sheet material
- B01D46/521—Particle separators, e.g. dust precipitators, using filters embodying folded corrugated or wound sheet material using folded, pleated material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
- B01D29/01—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with flat filtering elements
- B01D29/012—Making filtering elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
- B01D29/01—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with flat filtering elements
- B01D29/05—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with flat filtering elements supported
- B01D29/07—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with flat filtering elements supported with corrugated, folded or wound filtering sheets
-
- 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
- B01D46/0001—Making filtering elements
-
- 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
- B01D46/10—Particle separators, e.g. dust precipitators, using filter plates, sheets or pads having plane surfaces
- B01D46/106—Ring-shaped filtering elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2265/00—Casings, housings or mounting for filters specially adapted for separating dispersed particles from gases or vapours
- B01D2265/04—Permanent measures for connecting different parts of the filter, e.g. welding, glueing or moulding
Abstract
A length of glass fibre filter paper is divided by perforations 6 into strips designed to form respective filter elements, and beads of adhesive 7 are applied to each strip upstream of a pleating machine. The adhesive completes its curing in the machine, so that when the pleated strips are separated their pleats assume a radial configuration (Fig. 5) with the radially inner ends of the pleats bonded together, ready to be placed in an annular casing. <IMAGE>
Description
FILTER ELEMENT
The present invention relates to a method of making a pleated filter element and to the pleated filter element so produced.
Pleated filter elements formed from glass fibre paper are widely used as dust filters in respirators.
The pleated filter element may be arranged in a housing so that the pleats are parallel to one another or so that the pleats are radial to a common centre and the filter element forms an annulus within a cylindrical housing. The housing holding the pleated filter element may be a lid portion of a respirator whose main body holds a filter of absorbent particles, for example graphite particles.
As filter respirators are generally made of circular shape, if the filter element is arranged in the housing in parallel pleats, the pleated filter element must be cut to the desired circular shape to fit into the filter housing. This is not an easy process and it is preferred to use a radial filter, that is one where the pleats are arranged radially, so that the filter is made from a strip of glass fibre paper of the same width throughout, which is a width equal to the width of the annulus in the filter housing into which the pleated filter element is fitted.
However there is still a problem in assembling the filter. The pleated filter element is obtained from the pleating apparatus, which may be a rotary pleater or a blade pleater, as a slab of pleated filter paper in compression so that the surfaces of the folded portions of the filter paper are in full contact with the adjacent surfaces.
This slab of compressed pleated filter paper has to be transferred to the annular filter housing and allowed to expand within the annulus of the housing without the pleats springing open prematurely. This transfer requires considerable care by an operator, and precautions must be taken, for example by using elastic bands to hold the slabs in the compressed state, to ensure that the pleats do not open prematurely.
The assembly of the pleated filter is therefore necessarily a slow process and does not lend itself to the production of a filter respirator at a commercially acceptable speed on a production line.
It is a main object of the present invention to overcome this problem of assembling a pleated filter element into a filter housing in which the pleats are radial.
According to the present invention there is provided a method of making a pleated filter element which comprises the steps of advancing a filter medium to a pleating machine, and utilising the pleating machine to produce folds in the filter medium transversely to its direction of advance and to compress the folds in the filter medium to produce a pleated filter element, wherein a bead of hot melt adhesive is applied to a surface of the advancing filter medium at a position corresponding to an edge of a pleated filter element formed therefrom, the hot melt adhesive being applied before the filter medium is fed to the pleating machine, and the hot melt adhesive having a curing time such that the adhesive is not fully cured until the compressed pleated filter element has been formed in the pleating machine, whereby corresponding edges of the surfaces of the two parts of each pleat are adhered together and a band of adhesive is formed which bonds adjacent pleats to one other.
A pleated filter element formed by the method of the present invention therefore has one edge surface of each pleat bonded, and the other edge surface of each pleat free and able to expand to form a radial filter when the pleated filter element is introduced into the annulus of a filter housing.
Advantageously a sheet of filter medium is advanced to the pleating machine, a plurality of longitudinal rows of perforations are formed in the sheet to define the width of filter elements to be formed from the sheet, and a bead of hot melt adhesive is applied adjacent to each row of perforations.
Preferably the sheet is of a width to form an exact number of filter elements, the sheet is perforated accordingly, and a bead of hot melt adhesive is additionally provided adjacent that edge of the sheet which has no bead of hot melt adhesive between the said edge and the nearest row of perforations.
Further in accordance with the present invention there is provided a pleated filter element comprising a strip of filter medium folded to form a succession of pleats, each of which has two parts, one edge portion of one surface of each part of a pleat being bonded to a corresponding edge portion of one surface of the other part of the same pleat, and a band of adhesive adjacent the bonded edge portions of the pleats bonding each pleat to the adjacent pleats.
Preferably the band of adhesive bonds each pleat to the adjacent pleats at the edges of the folds constituting the junctions between adjacent pleats.
The present invention will be further understood from the following detailed description which is made with reference to the accompanying drawings, in which:
Figure 1 is a plan view of a known radial filter,
Figure 2 is a side view of the radial filter of
Figure 1 with part of the end cut away to show part of the pleated filter element used,
Figure 3 is a flow diagram of a method of making a pleated filter element in accordance with the present invention,
Figure 4 is a plan view of a sheet of filter medium immediately before it is fed to a pleating machine in the method of Figure 3, and
Figure 5 is a fragmentary perspective view of a preferred embodiment of a pleated filter element in accordance with the present invention.
In Figure 1 of the accompanying drawings there is indicated generally at 1 a radial dust filter comprising a pleated filter element 2 arranged as an annulus within a filter housing 3.
Figure 2 shows a side view of the radial dust filter 1 with a small portion of the filter housing 3 cut away to show one pleat 4 of the pleated filter element 2.
In a preferred method in accordance with the present invention illustrated in the flow diagram which is Figure 3, a 228mm wide sheet of glass fibre paper is withdrawn from a supply roll and advanced towards a pleating machine. As the glass fibre paper is advanced five rows of perforations are formed in the sheet of glass fibre paper to define six strips each 38mm wide.Six beads of hot melt adhesive, preferably an adhesive based on ethylene vinyl acetate and including terpene phenolic resin and a rosin ester hydrocarbon wax, are applied to one surface of the advancing perforated glass fibre paper so that a bead of the hot melt adhesive is applied adjacent to each row of perforations and to one edge of the sheet as shown in Figure 4 where the sheet of glass fibre paper is denoted by the reference numeral 5, the rows of perforations are denoted by the reference numeral 6, and the beads of hot melt adhesive by the reference numeral 7. It will be noted that each of the beads 7 of hot melt adhesive is applied to the sheet 5 near to the edge of one of the six strips into which the sheet 5 is sub-divided by the five rows of perforations 6.
The adhesive is applied to the surface of the sheet 5 of glass fibre paper in a condition in which the adhesive will take a minute or two to cure. The time allowed for curing of the adhesive is selected so that the sheet 5 of glass fibre paper may be pleated before the adhesive is fully cured.
The glass fibre paper, perforated and carrying the six beads 7 of adhesive, is fed to a pleating machine, preferably a rotary pleating machine, in which the pleats are formed in conventional manner by forming folds in the glass fibre paper in opposite directions and then compressing the glass fibre paper by slowing its rate of advance within the pleating machine so that the glass fibre paper is folded up on itself to form pleats 4 as shown in Figure 2.
On one surface of each part of each pleat there is present a line of adhesive which is part of one of the beads of hot melt adhesive. As the pleats are compressed, the surfaces of the two parts of each pleat are brought into face to face contact so that the adhesive on the one surface of one part of each pleat contacts the adhesive on the similar surface of the other part of the pleat. At this time the adhesive is not fully cured, and, as the adhesive subsequently cures, the pleated sheet of glass fibre paper is held with the adjacent individual pleats 4 closed. The applied pressure causes adhesive to be displaced upwardly from between each pleat 4 to link up with adhesive similarly displaced from between the other pleats 4 and form a band above the folds which constitute the junctions between adjacent pleats 4.Thus, when the adhesive is fully cured, individual pleats 4 are held closed by adhesive in each of the six sections of the pleated sheet 5, and the corners of the individual pleats in each section are bonded together by a band of adhesive extending along the line of the perforations or along the edge of the pleated sheet 5.
The pleating machine counts the number of pleats, for example 110 pleats to a pleated filter element 2, and cuts the glass fibre paper to produce a slab comprising a set of six pleated filter elements which the operator can remove from the pleating machine without fear of the pleats springing open. The operator can then separate the slab into six pleated filter elements 2 by tearing along the lines of the perforations 6 and there will be obtained six pleated filter elements each having the adjacent edge surfaces of the two parts of each pleat held together by adhesive and also having adjacent pleats held together by the band of adhesive at the edges of one set of folds in the pleated filter element.
The operator can then take a pleated filter element and place it in the annulus in a filter housing 3 with the edge of the band of adhesive against the inner surface of the annulus, which is the surface of smaller circumference. As the pleated filter element of the present invention is introduced into the annulus in the filter housing 3, the pleats will open across the width of the annulus, but there will be no risk of the whole pleated filter element springing open and getting out of control as tended to happen with prior art pleated filter elements. Thus filters can be assembled easily and quickly at a commercial rate of production.
In Figure 5 there is shown a fragmentary perspective view of a pleated filter element in accordance with the invention in the position which it adopts in the annulus in the filter housing 3. The pleated filter element comprises a series of pleats such as pleat 14 having surfaces 15 and 16 which are held together by lines of cured adhesive at positions corresponding to the line 17 of adhesive shown at the end of the pleated filter element. In addition the individual pleats 14 are held together by a band 18 of cured adhesive at the corners of the folds between adjacent pleats 14.
In the embodiment of the invention being described the other surfaces 19 and 20 of an individual pleat 14 are not adhered to the corresponding surfaces of a neighbouring pleat 14. However it is within the scope of the present invention for additional beads of adhesive to be applied to the other surface of the sheet 5 of glass fibre paper at positions corresponding to the positions of the beads 7 applied to the said one surface of the sheet 5. In this case adjacent pleats 14 of the pleated filter element are adhered at the same edge as the two parts of each pleat 14 are adhered. The pleats will still open appropriately when a pleated filter element is assembled in an annulus in a filter housing to form a radial filter.
In the preferred embodiment of the present invention which has been described, the sheet of glass fibre paper is perforated before the beads of hot melt adhesive are applied. However, the method may be modified so that the sheet of glass fibre paper is perforated after the beads of hot melt adhesive have been applied.
Claims (5)
1. A method of making a pleated filter element which comprises the steps of advancing a filter medium to a pleating machine, and utilising the pleating machine to produce folds in the filter medium transversely to its direction of advance and to compress the folds in the filter medium to produce a pleated filter element, wherein a bead of hot melt adhesive is applied to a surface of the advancing filter medium at a position corresponding to an edge of a pleated filter element formed therefrom, the hot melt adhesive being applied before the filter medium is fed to the pleating machine, and the hot melt adhesive having a curing time such that the adhesive is not fully cured until the compressed pleated filter element has been formed in the pleating machine, whereby corresponding edges of the surfaces of the two parts of each pleat are adhered together and a band of adhesive is formed which bonds adjacent pleats to one other.
2. A method according to Claim 1 wherein a sheet of filter medium is advanced to the pleating machine, a plurality of longitudinal rows of perforations are formed in the sheet to define the width of filter elements to be formed from the sheet, and a bead of hot melt adhesive is applied adjacent to each row of perforations.
3. A method according to Claim 2, wherein the sheet is of a width to form an exact number of filter elements, the sheet is perforated accordingly, and a bead of hot melt adhesive is additionally provided adjacent that edge of the sheet which has no bead of hot melt adhesive between the said edge and the nearest row of perforations.
4. A method according to any one of the preceding
Claims wherein hot melt adhesive is applied to the other surface of the advancing filter medium at a position or positions corresponding to the position or positions at which hot melt adhesive is applied to the one surface of the filter medium.
5. A pleated filter element made by a method according to any one of the preceding Claims.
5. A method of making a pleated filter element substantially as hereinbefore described with reference to the accompanying drawings.
6. A pleated filter element made by a method according to any one of the preceding Claims.
7. A pleated filter element comprising a strip of filter medium folded to form a succession of pleats, each of which has two parts, one edge portion of one surface of each part of a pleat being bonded to a corresponding edge portion of one surface of the other part of the same pleat, and a band of adhesive adjacent the bonded edge portions of the pleats bonding each pleat to the adjacent pleats.
8. A pleated filter element according to Claim 7 wherein the band of adhesive bonds each pleat to the adjacent pleats at the edges of the folds constituting the junctions between adjacent pleats.
9 A pleated filter element according to Claim 7 or Claim 8, wherein the edge portions of the other surfaces of each part of a pleat are bonded to corresponding edge portions of the other surfaces of adjacent pleats.
10. A pleated filter element substantially as hereinbefore described and illustrated in Figure 5 of the accompanying drawings.
Amendments to the claims have been filed as follows
1. A method of making pleated filter elements which
comprises the steps of advancing a sheet of filter medium
to a pleating machine, and, during said advance, forming
a plurality of longitudinal rows of perforations in
the sheet to define the widths of filter elements to
be formed from the sheet, applying a bead of hot melt
adhesive to one surface of the advancing sheet of filter medium adjacent to each row of perforations, and
thereafter utilising the pleating machine to produce
folds in the sheet of filter medium transversely to
its direction of advance and to compress the folds in
the sheet of filter medium to produce a set of pleated
filter elements, the hot melt adhesive which is applied
to the sheet of filter medium at positions corresponding
to the edges of pleated filter elements formed therefrom
having a curing time such that the adhesive is not fully
cured until the set of compressed pleated filter elements
has been formed in the pleating machine, whereby
corresponding edges of the surfaces of the two parts
of each pleat are adhered together and a band of adhesive
is formed which bonds adjacent pleats of each pleated
filter element to one other.
2. A method according to Claim 1, wherein the sheet
is of a width to form an exact number of filter elements, the sheet is perforated accordingly, and a bead of hot melt adhesive is additionally provided adjacent that edge of the sheet which has no bead of hot melt adhesive between the said edge and the nearest row of perforations.
3. A method according to either of the preceding
Claims wherein hot melt adhesive is applied to the other surface of the advancing filter medium at positions corresponding to the positions at which hot melt adhesive is applied to the one surface of the filter medium.
4. A method of making a pleated filter element substantially as hereinbefore described with reference to the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8823806A GB2223695A (en) | 1988-10-11 | 1988-10-11 | Making radially pleated filter elements |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8823806A GB2223695A (en) | 1988-10-11 | 1988-10-11 | Making radially pleated filter elements |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8823806D0 GB8823806D0 (en) | 1988-11-16 |
| GB2223695A true GB2223695A (en) | 1990-04-18 |
Family
ID=10645010
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8823806A Withdrawn GB2223695A (en) | 1988-10-11 | 1988-10-11 | Making radially pleated filter elements |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2223695A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0812610A2 (en) * | 1996-06-10 | 1997-12-17 | Fram Europe Limited | Fluid filter element and method of manufacture |
| CN107551701A (en) * | 2016-03-31 | 2018-01-09 | 孙欣 | Tilting cooking fume filter |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB848129A (en) * | 1958-03-12 | 1960-09-14 | Gen Motors Ltd | Improvements in or relating to filters for fluids |
| GB867004A (en) * | 1959-03-03 | 1961-05-03 | Gen Motors Ltd | Improvements in or relating to filters for fluids |
| GB1408194A (en) * | 1971-07-28 | 1975-10-01 | Delbag Luftfilter Gmbh | Filter pack and method for forming the same |
| GB1429783A (en) * | 1972-03-11 | 1976-03-24 | Gen Motors Ltd | Fluid filter units |
| GB2030464A (en) * | 1978-09-21 | 1980-04-10 | Gen Motors Ltd | Fluid filter elements and their manufacture |
| EP0206182A1 (en) * | 1985-06-15 | 1986-12-30 | Kabushiki Kaisha Tsuchiya Seisakusho | Fluid filter with pleated filter medium |
-
1988
- 1988-10-11 GB GB8823806A patent/GB2223695A/en not_active Withdrawn
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB848129A (en) * | 1958-03-12 | 1960-09-14 | Gen Motors Ltd | Improvements in or relating to filters for fluids |
| GB867004A (en) * | 1959-03-03 | 1961-05-03 | Gen Motors Ltd | Improvements in or relating to filters for fluids |
| GB1408194A (en) * | 1971-07-28 | 1975-10-01 | Delbag Luftfilter Gmbh | Filter pack and method for forming the same |
| GB1429783A (en) * | 1972-03-11 | 1976-03-24 | Gen Motors Ltd | Fluid filter units |
| GB2030464A (en) * | 1978-09-21 | 1980-04-10 | Gen Motors Ltd | Fluid filter elements and their manufacture |
| EP0206182A1 (en) * | 1985-06-15 | 1986-12-30 | Kabushiki Kaisha Tsuchiya Seisakusho | Fluid filter with pleated filter medium |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0812610A2 (en) * | 1996-06-10 | 1997-12-17 | Fram Europe Limited | Fluid filter element and method of manufacture |
| EP0812610A3 (en) * | 1996-06-10 | 1998-03-25 | Fram Europe Limited | Fluid filter element and method of manufacture |
| GB2314031B (en) * | 1996-06-10 | 1999-12-15 | Fram Europ | Fluid filter element and method of manufacture |
| CN107551701A (en) * | 2016-03-31 | 2018-01-09 | 孙欣 | Tilting cooking fume filter |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8823806D0 (en) | 1988-11-16 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |