US4501782A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for bonding webs employing ultrasonic energy
Assignee: Mac Gil Ltd
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Filing: 1983-11-18
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Granted: 1985-02-26
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Expires: 2003-11-18
Abstract
Abstract A method for bonding thermoplastic webs includes the steps of interdigitating the ends of the warps at opposing web edges, with the length of the interdigitation insuring that the end of an interdigitated filament overlies the first shute of the opposing web, and with the interdigitated fibers being subsequently ultrasonically bonded in a continuous manner across the width of the web so that the ends are crushed down and flattened over the corresponding shute. The warp ends may overlie a number of opposing shutes as long as the overlap is no more than 11/2 times the thickness of the web. The web bonding method for producing a continuous belt produces a web joint which is substantially coplanar with the remainder of the web such that the web is uniquely adapted to papermaking processes which avoids bumps or ripples in the sluice that solidifies on the web. In a further embodiment, ultrasonic energy is utilized to bind the web edges.
Inventors
- 👤 Gilbert Weatherly
- 👤 A. MacDonald Slade
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:53
CPC Classifications
B; B29; B29C; B29C66/00; B29C66/69; B29C65/00; B29C65/02; B29C65/08; B29C66/70; B29C66/72; B29C66/729; B29C66/73; B29C66/739; B29C66/7392; B29C66/73921; B29C66/80; B29C66/83; B29C66/836; B29C66/84; B29C66/865; B29C66/8652; B29C66/86531; B29C66/86533; D; D21; D21F; D21F1/00; D21F1/0027; D21F1/0054; B29C66/71; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1036; Y10T156/1051; Y10T428/00; Y10T428/19; Y10T428/24; Y10T428/24777; Y10T428/24785
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
252 words
A method for bonding heat-set thermoplastic webs to provide a web loop for use as a Fourdrinier wire for papermaking processes comprising the steps of: providing a length of heat-set thermoplastic woven web, with the web having two free laterally running ends with warps projecting therefrom; removing a predetermined number of shutes from each of the ends; folding the web back on itself to form a loop having a longitudinal axis such that the opposite ends of the web are in spaced-apart opposition; interdigitating the warps of the opposed ends to form a seam by moving one web end toward the other web end such that a warp extending from one end overlies or underlies at least one shute of the other end; and ultrasonically bonding the overlain or underlain shutes to respective warps by placing the web seam between a platten and an ultrasonic welding head and moving the ultrasonic head transversely to the longitudinal axis of the web along the edges containing the interdigitated warps while the face of the welding head exerts a force directed towards the platten on the seam to provide a continuous bond across the web by ultrasonic welding and crushing down the warps over the corresponding shutes, such that a flat seam coplanar with the web is formed, whereby when the web loop is used in a papermaking process, the resulting solidifying sluice is substantially ripple and bump free over the seam and whereby liquid is permitted to pass through the web at the seam.
Claim 2
Independent Claim
252 words
A method for bonding heat-set thermoplastic webs to provide a web loop for use as a Fourdrinier wire for papermaking processes comprising the steps of: providing a length of heat-set thermoplastic woven web, with the web having two free laterally running ends with warps projecting therefrom; removing a predetermined number of shutes from each of the ends; folding the web back on itself to form a loop having a longitudinal axis such that the opposite ends of the web are in spaced-apart opposition; interdigitating the warps of the opposed ends to form a seam by moving one web end toward the other web end such that a warp extending from one end overlies or underlies at least one shute of the other end; and ultrasonically bonding the overlain or underlain shutes to respective warps by placing the web seam between a platten and an ultrasonic welding head and moving the ultrasonic head transversely to the longitudinal axis of the web along the edges containing the interdigitated warps while the face of the welding head exerts a force directed towards the platten on the seam to provide a continuous bond across the web by ultrasonic welding and crushing down the warps over the corresponding shutes, such that a flat seam coplanar with the web is formed, whereby when the web loop is used in a papermaking process, the resulting solidifying sluice is substantially ripple and bump free over the seam and whereby liquid is permitted to pass through the web at the seam.
Claim 3
Dependent Claim
35 words
The method of claim 1 wherein the length of the overlap provided by the length of the free ends of the warps at one end is less than 11/2 times the thickness of the web.
Claim 4
Dependent Claim
18 words
The method of claim 1 and further including the step of ultrasonically bonding the edges of the web.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein the interleaving matches the original woven pattern.
Claim 6
Dependent Claim
10 words
The method of claim 1 wherein the interleaving is random.
Claim 7
Dependent Claim
16 words
The method of claim 2 wherein the shute removing step takes place after the folding step.
Claim 8
Dependent Claim
21 words
The method of claim 2 wherein the warps of one end overlie or underlie only one shute of the opposing end.
Claim 9
Dependent Claim
10 words
The method of claim 1 wherein no shutes are removed.
Claim 10
Dependent Claim
22 words
The method of claim 1 wherein ultrasonic energy is applied continuously during movement of the ultrasonic welding head in the bonding step.
Claim 11
Dependent Claim
9 words
The product made by the method of claim 1.
Claim 12
Dependent Claim
9 words
The product made by the method of claim 2.
Claim 13
Dependent Claim
9 words
The product made by the method of claim 3.
Claim 14
Dependent Claim
9 words
The product made by the method of claim 4.
Claim 15
Dependent Claim
9 words
The product made by the method of claim 5.
Claim 16
Dependent Claim
9 words
The product made by the method of claim 6.
Claim 17
Dependent Claim
9 words
The product made by the method of claim 7.
Claim 18
Dependent Claim
9 words
The product made by the method of claim 8.
Claim 19
Dependent Claim
9 words
The product made by the method of claim 9.
References Cited (Backward Citations)
US3966519A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-26 | 1988-08-27 | 1989-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-26 | 1992-08-27 | 1993-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-26 | 1996-08-27 | 1997-02-26 | $7700.00 | Window Closed / Lapsed |