US3716436A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making a back pressure resistant filter element
Assignee: Pall Corp
•
Filing: 1970-03-16
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Granted: 1973-02-13
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Expires: 1990-03-16
Abstract
Abstract A corrugated cylindrical filter element is disposed about a central core. A perforated plastic bonding sheet is disposed between the core and the filter. The bonding sheet is bonded in situ to the inner tips of the corrugations only.
Inventors
- 👤 D Pall
- 👤 T Jasaitis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:53
CPC Classifications
B; B01; B01D; B01D29/00; B01D29/11; B01D29/111; B01D29/13; B01D29/15; B01D29/21; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1036; Y10T156/1038
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
202 words
A process for making a corrugated filter element formed in a closed configuration extending about a core, with the corrugations extending longitudinally of the core, and the inner tips of the corrugations disposed in a fixed radial relationship to each other in proximity to the core, comprising disposing a foraminous softenable plastic bonding sheet about a temporary support which is not affected by the method or means of softening the sheet; disposing a corrugated filter sheet in a closed configuration about the support with the corrugations extending longitudinally of the support and the inner tips of the corrugations in proximity to the bonding sheet on the temporary support; softening the plastic bonding sheet and bringing the inner tips of the corrugation into contact with the bonding sheet displacing the plastic material about at least a portion of the inner tips of the corrugations with the corrugations disposed about the sup-port in a fixed radial relationship to each other; and then hardening the softened plastic bonding sheet, thereby bonding the inner tips of the corrugations of the filter sheet to the bonding sheet to fix said inner tips against displacement; removing the temporary support and inserting a permanent support core in its place.
Claim 2
Dependent Claim
202 words
A process for making a corrugated filter element formed in a closed configuration extending about a core, with the corrugations extending longitudinally of the core, and the inner tips of the corrugations disposed in a fixed radial relationship to each other in proximity to the core, comprising disposing a foraminous softenable plastic bonding sheet about a temporary support which is not affected by the method or means of softening the sheet; disposing a corrugated filter sheet in a closed configuration about the support with the corrugations extending longitudinally of the support and the inner tips of the corrugations in proximity to the bonding sheet on the temporary support; softening the plastic bonding sheet and bringing the inner tips of the corrugation into contact with the bonding sheet displacing the plastic material about at least a portion of the inner tips of the corrugations with the corrugations disposed about the sup-port in a fixed radial relationship to each other; and then hardening the softened plastic bonding sheet, thereby bonding the inner tips of the corrugations of the filter sheet to the bonding sheet to fix said inner tips against displacement; removing the temporary support and inserting a permanent support core in its place.
Claim 3
Dependent Claim
27 words
A process for making a filter element in accordance with claim 1, including a disposing a separator sheet between the temporary support and the foraminous bonding sheet.
Claim 4
Dependent Claim
34 words
A process for making a filter element in accordance with claim 1, in which the foraminous bonding sheet is of a thermoplastic material and the temporary support is of a relatively non-heat sensitive material.
Claim 5
Dependent Claim
29 words
A process for making a filter element in accordance with claim 1, in which the bonding sheet is made of polypropylene, and the temporary support is made of metal.
Claim 6
Dependent Claim
27 words
A process for making a filter element in accordance with claim 1, including applying pressure to ensure firm contact between the corrugation tips and the bonding sheet.
Claim 7
Dependent Claim
50 words
A process for making a filter element in accordance with claim 1, which comprises placing springs about the outer periphery of the corrugated filter sheet, to press the corrugated sheet against the foraminous softenable plastic bonding sheet, to ensure firm contact between the inner corrugation tips and the bonding sheet.
Claim 8
Dependent Claim
34 words
A process for making a filter element in accordance with claim 1, in which the temporary support is removed and the permanent support inserted by pushing the temporary support out with the permanent support.
Claim 9
Dependent Claim
59 words
A process for making a filter element in acCordance with claim 1, in which the corrugated filter sheet is formed in a closed configuration about the temporary support with the side edges of the sheet extending longitudinally of the support and lapped in a side seam, and sealing the side seam to close the side of the filter element.
References Cited (Backward Citations)
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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) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |