Patent US3857329A successfully refreshed from Google Patents.
US3857329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of a carrying bag from thermoplastic synthetic film
Assignee: Individual
•
Filing: 1973-07-18
•
Granted: 1974-12-31
•
Expires: 1993-07-18
Abstract
Abstract To make an expansible side-infolded carrying bag of thermoplastic synthetic plastic film, with opposed grip bars bonded across the mouth top by relatively simple apparatus, a flat tubular film web as starting material is continuously formed from single layer stock, the web is rectangularly oppositely edge-notched at locations corresponding to bag lengths, the edges are infolded to the notching depth and successive bag lengths severed at leading notch edges, defining on the web end a mouth readily opened for easy insertion, for each bag without infold interference, of paired superimposed grips bars thereafter welded to respective mouth margins; a transverse bottom seam for an open-mouthed bag or a mouth-closing seam below the grip bars for a bottom-filled packaging bag being welded before or simultaneously with the grip welds; with disclosure of method variations.
Inventors
- 👤 M Lehmacher
- 👤 H Lehmacher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:23
CPC Classifications
B; B31; B31B; B31B70/00; B31B70/74; B31B70/86; B31B70/864; B31B2160/00; B31B2160/10; Y; Y10; Y10S; Y10S493/00; Y10S493/916; Y10S493/926
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
252 words
A method for fabrication of carrying bags from thermoplastic synthetic plastic film, each bag with its longitudinal sides infolded throughout their lengths to form respective like infold panels joining respective edges of two opposed generally rectangular walls to constitute a bag body, and at the bag mouth having a carrying grip structure comprised of opposed parallel grip bars extending substantially across the bag body width and attached to a mouth inner margin of a respective wall; said method comprising the steps of; providing a continuous web of flattened tubular thermoplastic synthetic plastic film comprised of two film layers continuously longitudinally connected at both edges, and advancing the web longitudinally; at longitudinal spacing corresponding to desired product bag length, producing successively spaced pairs of edge notches through both web layers, the notches of each pair at opposite locations in the respective web edges, each notch having a depth corresponding substantially to the depth of the product side fold panel width; producing in the advancing web after said notches like longitudinal side infolds on both edges; transversely severing the advancing web across the leading edges of the successive notch pairs, to separate successive bag sections from the leading end of the web, the severance of each bag section defining the mouth margins of a following bag section; spreading the film layers at successively defined mouth margins and inserting the said grip bars between the spread layers at the mouth region; and transversely welding the respective bag wall mouth margins to the inserted grip bars.
Claim 2
Independent Claim
252 words
A method for fabrication of carrying bags from thermoplastic synthetic plastic film, each bag with its longitudinal sides infolded throughout their lengths to form respective like infold panels joining respective edges of two opposed generally rectangular walls to constitute a bag body, and at the bag mouth having a carrying grip structure comprised of opposed parallel grip bars extending substantially across the bag body width and attached to a mouth inner margin of a respective wall; said method comprising the steps of; providing a continuous web of flattened tubular thermoplastic synthetic plastic film comprised of two film layers continuously longitudinally connected at both edges, and advancing the web longitudinally; at longitudinal spacing corresponding to desired product bag length, producing successively spaced pairs of edge notches through both web layers, the notches of each pair at opposite locations in the respective web edges, each notch having a depth corresponding substantially to the depth of the product side fold panel width; producing in the advancing web after said notches like longitudinal side infolds on both edges; transversely severing the advancing web across the leading edges of the successive notch pairs, to separate successive bag sections from the leading end of the web, the severance of each bag section defining the mouth margins of a following bag section; spreading the film layers at successively defined mouth margins and inserting the said grip bars between the spread layers at the mouth region; and transversely welding the respective bag wall mouth margins to the inserted grip bars.
Claim 3
Dependent Claim
46 words
The method as described in claim 1, including the further step of transversely seam welding the web forwardly adjacent each severing cut for formation of a respective bag bottom seam; said seam welding and the welding of the bag wall mouth margins being carried out simultaneously.
Claim 4
Dependent Claim
68 words
The method as described in claim 2, wherein: each two grip bars to be assembled are positioned in aligned superposed relation in the plane of the web path; by advance of the web the spread layers of the mouth margins are brought about the positioned grip bars with the web advance then halted, and thereafter carrying out the said welding of the layer margins to said respective layers.
Claim 5
Dependent Claim
95 words
A method for fabrication of carrying bags as described in claim 1, wherein simultaneously with each said severing and forwardly adjacent the respective severing cut, a transverse seam welding of the web is carried out to form a bottom seam weld in the severed bag section; after severing from the web each bag section is transported along a path extending in a direction trAnsverse to the web path direction; the steps comprising the said spreading, the said inserting and the said transversely welding are carried out on each bag section along the said transverse path.
Claim 6
Dependent Claim
88 words
A method for fabrication of carrying bags comprising the provision of two parallel advanced webs each operated upon as described in claim 4, and wherein bag sections severed from respective webs are transported simultaneously along the said path transverse to the web advance direction in pairs comprising a bag section from each web, to first, second and third work stations, where there are carried out on both bags sections of a pair simultaneously, respectively the steps comprising the said spreading, the said inserting and the said transversely welding.
Claim 7
Dependent Claim
99 words
A method for fabrication of carrying bags as described in claim 1, wherein: simultaneously with each said severing and forwardly adjacent the respective severing cut, a transverse seam welding of the web is carried out to form a bottom seam weld in the severed bag section; after severing from the web each bag section is transported along a path extending in a direction transverse to the web path direction to first, second and third work stations, where respectively the steps comprising the said spreading, the said inserting and the said transversely welding are carried out on each bag section.
Claim 8
Dependent Claim
69 words
The method as described in claim 1, wherein: each two grip bars to be assembled are positioned in aligned superposed relation in the plane of the web path; by advance of the web the spread layers of the mouth margins are brought about the positioned grip bars with the web advance then halted, and thereafter carrying out the said welding of the mouth margins to said respective grip bars.
Claim 9
Dependent Claim
35 words
The method as described in claim 1, including the further step of transversely seam welding the web rearwardly adjacent the location of each pair of grip bars welded to the respective bag wall mouth margins.
Claim 10
Dependent Claim
39 words
A method for fabrication of carrying bags as described in claim 2, including the further step of incising, through the web, grip hole cut-outs for each bag spaced rearwardly of, but adjacent, the locus for the respective grip bars.
References Cited (Backward Citations)
US2372008A
Cited
US3077820A
Cited
US2971874A
Cited
US3451316A
Cited
US3548723A
Cited
US3640187A
Cited
US3698289A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |