Patent US2647029A successfully refreshed from Google Patents.
EP0169698A2
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EP
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Improvements in filtering screens
Assignee: Schlumberger UK Holdings Ltd
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Filing: 1985-07-15
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Granted: —
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Expires: 2005-07-15
Abstract
Abstract A filtering screen is described comprising: a first filter mesh, a second filter mesh having a different mesh size from the first and overlying the first mesh, and an apertured support to which both of the meshes are bonded so as to maintain the two meshes in tension, the tension in one of the meshes being greater than that in the other. At least one other filter mesh may be bonded over the first two meshes. The support may comprise a plate of fibre reinforced material having apertures formed therein which are much greater in area than the openings in the filter mesh, or a sheet of metal in which apertures are formed and in which edge regions of each aperture are turned though aproximately 90° to extend normal to the plane of the sheet from the underside thereof to increase the rigidity of the sheet. In a second form of screen there is provided a frame, a first screen cloth of relatively coarse mesh adhesively secured at marginal edge portions around said frame, a second screen cloth having a relatively finer mesh than the first screen cloth and also adhesively secured at marginal edge portions around said frame, a third screen cloth superimposed on the second cloth and having a mesh which is relatively finer than the mesh of the second cloth, the third cloth also being adhesively secured at marginal edge portions around said frame, at least the first said screen cloth being tensioned and the second and third screen cloths being capable of vibrating so as to strike each other and the first mentioned screen cloth to dislodge particles which would otherwise clog the screen as the frame is vibrated.
Inventors
- 👤 Marshall Graham Bailey
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 22:13
CPC Classifications
B; B07; B07B; B07B1/00; B07B1/46; B07B1/4609; B07B1/4618; B01; B01D; B01D29/00; B01D29/01; B01D29/012; B01D29/05; B01D29/50; B01D29/52; B01D29/56; B01D29/62; B01D29/70; B01D29/72; B01D39/00; B01D39/10; B01D39/12; B07B1/4663; B07B1/4672; B07B1/469; B07B1/48; B07B1/50
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
63 words
A filtering screen comprising: - a first filter mesh, - a second filter mesh having a different mesh size from the first and overlying the first mesh, and - an apertured support to which both of the meshes are bonded so as to maintain the two meshes in tension, the tension in one of the meshes being greater than that in the other.
Claim 2
Dependent Claim
63 words
A filtering screen comprising: - a first filter mesh, - a second filter mesh having a different mesh size from the first and overlying the first mesh, and - an apertured support to which both of the meshes are bonded so as to maintain the two meshes in tension, the tension in one of the meshes being greater than that in the other.
Claim 3
Dependent Claim
23 words
A filtering screen as claimed in claim 1, in which at least one other filter mesh is bonded over the first two meshes.
Claim 4
Dependent Claim
35 words
A filtering screen as claimed in claim 1, wherein the support comprises a plate of fibre reinforced material having apertures formed therein which are much greater in area than the openings in the filter mesh.
Claim 5
Dependent Claim
39 words
A filtering screen as claimed in claim 1, wherein the screen support is in the form of a rectilinear frame of rigid struts similar to a picture frame with transversely extending intermediate struts to define apertures within the frame.
Claim 6
Dependent Claim
55 words
A filtering screen as claimed in claim 1, wherein the support is a rigid sheet of metal in which apertures are formed and in which edge regions of each aperture are turned through aproximately 90° to extend normal to the plane of the sheet from the underside thereof to increase the rigidity of the sheet.
Claim 7
Dependent Claim
15 words
A filtering screen as claimed in claim 1, wherein the support is a honeycomb structure.
Claim 8
Dependent Claim
21 words
A filtering screen as claimed in claim 1 wherein the bonding agent is a thermosetting adhesive or a chemically setting adhesive.
Claim 9
Independent Claim
119 words
A method of making a filtering screen comprising the steps of: - coating the upper and lower surfaces of a honeycomb structure with a resin or glue so as to reinforce and increase the thickness of the wall of the honeycomb in the region of at least one face thereof, - tensioning a first screen mesh to the said one face of the honeycomb, - similarly tensioning a second screen mesh over the first mesh the tension in the second screen mesh being less than that in the first, and securing the two meshes in position by glue or resin, and - securing by a glue or resin apertured sheet material to the other side of the honeycomb structure.
Claim 10
Independent Claim
119 words
A method of making a filtering screen comprising the steps of: - coating the upper and lower surfaces of a honeycomb structure with a resin or glue so as to reinforce and increase the thickness of the wall of the honeycomb in the region of at least one face thereof, - tensioning a first screen mesh to the said one face of the honeycomb, - similarly tensioning a second screen mesh over the first mesh the tension in the second screen mesh being less than that in the first, and securing the two meshes in position by glue or resin, and - securing by a glue or resin apertured sheet material to the other side of the honeycomb structure.
Claim 11
Dependent Claim
42 words
A filtering screen as claimed in claim 1, wherein the apertured support is flexible and is adapted to be flattened on being filtered into a sifting machine so as to restore the desired differential tensions in the meshes on being fitted therein.
Claim 12
Dependent Claim
140 words
A sifting screen assembly for use in a vibratory, sifting machine comprising a frame, a first screen cloth of relatively coarse mesh adhesively secured at marginal edge portions around said frame, a second screen cloth having a relatively finer mesh than the first screen cloth and also adhesively secured at marginal edge portions around said frame, a third screen cloth superimposed on the second cloth and having a mesh which is relatively finer than the mesh of the second cloth, the third cloth also being adhesively secured at marginal edge portions around said frame, at least the first said screen cloth being tensioned and the second and third screen cloths being capable of vibrating so as to strike each other and the first mentioned screen cloth to dislodge particles which would otherwise clog the screen as the frame is vibrated.
Claim 13
Dependent Claim
140 words
A sifting screen assembly for use in a vibratory, sifting machine comprising a frame, a first screen cloth of relatively coarse mesh adhesively secured at marginal edge portions around said frame, a second screen cloth having a relatively finer mesh than the first screen cloth and also adhesively secured at marginal edge portions around said frame, a third screen cloth superimposed on the second cloth and having a mesh which is relatively finer than the mesh of the second cloth, the third cloth also being adhesively secured at marginal edge portions around said frame, at least the first said screen cloth being tensioned and the second and third screen cloths being capable of vibrating so as to strike each other and the first mentioned screen cloth to dislodge particles which would otherwise clog the screen as the frame is vibrated.
Claim 14
Dependent Claim
58 words
A sifting screen assembly as claimed in claim 10 wherein the second and third screen cloths are also tensioned, each to a progressively lesser extent, so that the second screen cloth is tensioned by an amount less than the first screen cloth and the third screen cloth is tensioned to an extent less than the second screen cloth.
Claim 15
Dependent Claim
60 words
A sifting screen assembly as claimed in claim 10 or claim 11, wherein the first, lowermost, screen cloth has a mesh size in the range 10 to 30, the second, intermediate screen cloth, has a mesh size in the range of 30 to 325 and the third, upper screen cloth, has a mesh size in the range 40 to 325.
Claim 16
Dependent Claim
61 words
A sifting screen assembly as claimed in claim 10, 11 or 12, wherein the first screen cloth is tensioned in the range 50 to 90% of its tensile strength, the second screen cloth is tensioned in the range of 10 to 80% of its tensile strength and the third screen cloth is tensioned from 0 to 75% of its tensile strength.
Claim 17
Dependent Claim
41 words
A sifting screen assembly as claimed in claim 13 wherein the first cloth tension is 70%, the second cloth tension is 60% and the third cloth tension 55% of the tensile strength of the material from which the cloths are formed.
Claim 18
Independent Claim
99 words
A method of making a sifting screen comprising the steps of: - tensioning a first relatively coarse mesh screen cloth over a rigid frame, - superimposing on the first screen cloth a second screen cloth of relatively finer mesh, - tensioning the latter to a lesser extent than the tension in the first coarse mesh screen cloth, - superimposing over the second screen cloth a third screen cloth of finer mesh than the second cloth, - tensioning the third screen cloth to a lesser extent than the second cloth, and - adhesively securing the screen cloth to the frame.
Claim 19
Independent Claim
99 words
A method of making a sifting screen comprising the steps of: - tensioning a first relatively coarse mesh screen cloth over a rigid frame, - superimposing on the first screen cloth a second screen cloth of relatively finer mesh, - tensioning the latter to a lesser extent than the tension in the first coarse mesh screen cloth, - superimposing over the second screen cloth a third screen cloth of finer mesh than the second cloth, - tensioning the third screen cloth to a lesser extent than the second cloth, and - adhesively securing the screen cloth to the frame.
Claim 20
Dependent Claim
30 words
A method of making a sifting screen as claimed in claim 15, wherein each screen cloth is adhesively secured to the frame before the next screen cloth is superimposed thereover.
Claim 21
Dependent Claim
14 words
A method as claimed in claim 14, wherein a heat curable adhesive is employed.
References Cited (Backward Citations)
No citation records indexed.
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