Patent US4838905A successfully refreshed from Google Patents.
US4838905A
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Filter element and method of making a filter element
Assignee: Parker Hannifin Ltd
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Filing: 1987-09-03
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Granted: 1989-06-13
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Expires: 2007-09-03
Abstract
Abstract A filter element comprises a relatively rigid fluid-permeable cylinder (5), around which is provided a body (7) of non-woven fibrous filter material. A jacket (6) of permeable material is positioned around the outer surface of the filter material, and is heat-shrunk onto the filter material in order to hold this under substantially uniform radial compression over the whole of its area.
Inventors
- 👤 Colin T. Billiet
- 👤 Robert M. Fielding
- 👤 Stephen N. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:14
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/0001; B01D39/00; B01D39/14; B01D39/20; B01D39/2003; B01D39/2017; B01D46/24; B01D46/2403; B01D46/2411; B29; B29C; B29C63/00; B29C63/18; B29C63/38; B29C63/42; B01D2275/00; B01D2275/10; B29L; B29L2031/00; B29L2031/14
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
120 words
A filter element comprising a relatively rigid, fluid-permeable cylinder, a body of non-woven fibrous filter material positioned around the outer surface of the cylinder, and a permeable jacket positioned around the outer surface of the filter material, the jacket being in the form of a tubular-woven fabric sleeve having weft yarns extending circumferentially of the jacket and warp yarns extending longitudinally of the jacket, the warp yarns and the weft yarns having different shrinkage characteristics, the jacket having been heat-shrunk on to the filter material, with the weft yarns having undergone greater shrinkage than the warp yarns during the heat-shrinking, and due to said shrinkage holding the filter material under substantially uniform radial compression over the whole of its area.
Claim 2
Dependent Claim
120 words
A filter element comprising a relatively rigid, fluid-permeable cylinder, a body of non-woven fibrous filter material positioned around the outer surface of the cylinder, and a permeable jacket positioned around the outer surface of the filter material, the jacket being in the form of a tubular-woven fabric sleeve having weft yarns extending circumferentially of the jacket and warp yarns extending longitudinally of the jacket, the warp yarns and the weft yarns having different shrinkage characteristics, the jacket having been heat-shrunk on to the filter material, with the weft yarns having undergone greater shrinkage than the warp yarns during the heat-shrinking, and due to said shrinkage holding the filter material under substantially uniform radial compression over the whole of its area.
Claim 3
Dependent Claim
16 words
Element of claim 1 in which the weft yarns have undergone shrinkage of up to 30%.
Claim 4
Dependent Claim
35 words
Element of claim 1 in which the warp yarns are heat-stabilized before being woven into the fabric sleeve such that the warp yarns have undergone substantially zero shrinkage during the heat shrinking of the jacket.
Claim 5
Dependent Claim
19 words
Element of claim 1 in which the filter material is a microporous material formed into a radially compressible body.
Claim 6
Dependent Claim
15 words
Element of claim 4 in which the filter material is non-woven borosilicate glass fiber material.
Claim 7
Dependent Claim
28 words
Element of claim 1 in which the body of filter material is formed by spirally winding a sheet of filter material around the outer surface of the cylinder.
Claim 8
Dependent Claim
17 words
Element of claim 6 in which successive windings are in direct surface-to-surface contact one with the other.
Claim 9
Dependent Claim
12 words
Element of claim 1 in which the fabric is of synthetic fiber.
Claim 10
Independent Claim
139 words
A method of making a filter element, comprising the steps of providing a relatively rigid fluid-permeable cylinder, providing a body of non-woven fibrous filter material around the outer surface of the cylinder, said body being capable of undergoing radial compression, providing a jacket in the form of a permeable, tubular-woven fabric sleeve having warp yarns and weft yarns with different shrinkage characteristics, positioning said jacket loosely, but closely, around the body of fibrous filter material, so that the weft yarns extend circumferentially around the jacket, heating the resulting assembly so that the jacket shrinks on to and radially compresses the filter material with the weft yarns shrinking more than the warp yarns during the heat shrinking, and cooling the assembly so that the jacket holds the filter material under substantially uniform radial compression over the whole of its area.
Claim 11
Independent Claim
139 words
A method of making a filter element, comprising the steps of providing a relatively rigid fluid-permeable cylinder, providing a body of non-woven fibrous filter material around the outer surface of the cylinder, said body being capable of undergoing radial compression, providing a jacket in the form of a permeable, tubular-woven fabric sleeve having warp yarns and weft yarns with different shrinkage characteristics, positioning said jacket loosely, but closely, around the body of fibrous filter material, so that the weft yarns extend circumferentially around the jacket, heating the resulting assembly so that the jacket shrinks on to and radially compresses the filter material with the weft yarns shrinking more than the warp yarns during the heat shrinking, and cooling the assembly so that the jacket holds the filter material under substantially uniform radial compression over the whole of its area.
Claim 12
Dependent Claim
26 words
Method of claim 9 in which the heat-shrinking is effected at a temperature not exceeding 150° C. and the weft yarns shrink by up to 30%.
Claim 13
Independent Claim
165 words
A method of making a filter element, comprising the steps of providing a relatively rigid fluid-permeable cylinder, providing a body of non-woven fibrous filter material around the outer surface of the cylinder, placing a permeable heat-shrinkable jacket around the outer surface of a rigid sleeve having inner and outer diameters that are each less than that of the original outer diameter of the body of filter material, the rigid sleeve having at one end thereof an end section tapering inwardly from an opening having an outer diameter greater than the original outer diameter of the body of filter material, forcing the body of filter material and inner cylinder axially into the rigid sleeve through the opening thereof to compress the filter material between the cylinder and the rigid sleeve, heating the assembly so that the jacket of heat-shrinkable material shrinks around the outer surface of the rigid sleeve, and axially removing the rigid sleeve while holding the cylinder and the heat-shrunk jacket axially in position.
Claim 14
Independent Claim
165 words
A method of making a filter element, comprising the steps of providing a relatively rigid fluid-permeable cylinder, providing a body of non-woven fibrous filter material around the outer surface of the cylinder, placing a permeable heat-shrinkable jacket around the outer surface of a rigid sleeve having inner and outer diameters that are each less than that of the original outer diameter of the body of filter material, the rigid sleeve having at one end thereof an end section tapering inwardly from an opening having an outer diameter greater than the original outer diameter of the body of filter material, forcing the body of filter material and inner cylinder axially into the rigid sleeve through the opening thereof to compress the filter material between the cylinder and the rigid sleeve, heating the assembly so that the jacket of heat-shrinkable material shrinks around the outer surface of the rigid sleeve, and axially removing the rigid sleeve while holding the cylinder and the heat-shrunk jacket axially in position.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-12 | 1992-12-12 | 1993-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-12 | 1996-12-12 | 1997-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-12 | 2000-12-12 | 2001-06-13 | $7700.00 | Window Closed / Lapsed |