Patent US3775222A successfully refreshed from Google Patents.
US3775222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat sealing apparatus
Assignee: Pembroke Carton and Printing Co Ltd
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Filing: 1971-04-12
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Granted: 1973-11-27
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Expires: 1991-04-12
Abstract
Abstract Air is heated and fed to a nozzle for hot air sealing a longitudinal seam in a web of material to continuously form a tube e.g. of different kinds of lining material in a carton lining machine required to be heated to different levels in order to form the seal. The air is fed at a regulated pressure, in parallel, through a heater block and a number of valve controlled passages bypassing the heater. The heat input to the heater and the amount of the air bypassing the heater are both controlled to give a required temperature level of the seam, regardless of the speed of formation of the tube.
Inventors
- 👤 P Aspin
- 👤 R Garwood
- 👤 P Wise
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:48
CPC Classifications
B; B29; B29C; B29C66/00; B29C66/40; B29C66/41; B29C66/43; B29C66/432; B29C66/4322; B29C53/00; B29C53/36; B29C53/38; B29C53/48; B29C65/00; B29C65/02; B29C65/10; B29C66/01; B29C66/05; B29C66/10; B29C66/13; B29C66/133; B29C66/80; B29C66/83; B29C66/834; B29C66/8341; B29C66/83411; B29C66/83413; B29C66/90; B29C66/91; B29C66/912; B29C66/9121; B29C66/914; B29C66/9141; B29C66/91431; B29C66/91441; B29C66/9161; B29C66/91651; B29C66/91655; B29C66/96; B29C66/961; B29C66/70; B29C66/71; B29C66/72; B29C66/723; B29C66/7232; B29C66/72327; B29C66/72328; B29C66/73; B29C66/739; B29C66/7392; B29C66/73921; B31; B31B; B31B70/00; B31B70/60; B31B70/64; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1007; Y10T156/1008; Y10T156/1013
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
132 words
Apparatus for continuously forming a tube including heat sealing apparatus comprising a gas nozzle and means for supplying hot gas to the nozzle including a heater, at least one heater bypass in parallel with the heater, valve means for controlling the flow of gas through each of the bypasses and means for controlling the heat input of the heater in response to the temperature of gas leaving the heater to maintain the temperature substantially constant, said nozzle being located at a fixed heat sealing station for sealing a longitudinal seam of the tube and means being provided for controlling said valve means in response to the speed of formation of the tube whereby the seam is heated to a required level regardless of its speed of travel through the heat sealing station.
Claim 2
Dependent Claim
132 words
Apparatus for continuously forming a tube including heat sealing apparatus comprising a gas nozzle and means for supplying hot gas to the nozzle including a heater, at least one heater bypass in parallel with the heater, valve means for controlling the flow of gas through each of the bypasses and means for controlling the heat input of the heater in response to the temperature of gas leaving the heater to maintain the temperature substantially constant, said nozzle being located at a fixed heat sealing station for sealing a longitudinal seam of the tube and means being provided for controlling said valve means in response to the speed of formation of the tube whereby the seam is heated to a required level regardless of its speed of travel through the heat sealing station.
Claim 3
Dependent Claim
45 words
Apparatus as claimed in claim 1 including a pair of draw rolls for drawing forward a web to form the tube and said means for controllinG said valve means electrically operates said valve means in response to the speed of rotation of the draw rolls.
Claim 4
Dependent Claim
91 words
Apparatus as claimed in claim 2 further including means for guiding a web drawn forward by the draw rolls into a tube with longitudinal edge portions of the web in close proximity at said fixed heat sealing station, said nozzle being arranged to introduce a blast of hot air between said longitudinal edge portions so that the adjacent surfaces of said longitudinal edge portions become tacky and a pair of nip rollers for sealing the tacky adjacent surfaces of said longitudinal edge portions together to thereby permanently to form the seam.
Claim 5
Dependent Claim
35 words
Apparatus as claimed in claim 3 wherein said nip rollers are geared together and resiliently loaded against each other, and the seam is drawn through the nip of said nip rollers by said draw rolls.
Claim 6
Dependent Claim
63 words
Apparatus as claimed in claim 3 wherein said guiding means comprises an idler roller, a forming plate and rollers and guides for forming the web into a flat tube against the forming plate with said longitudinal edge portions disposed perpendicular to the forming plate and held apart by further guides for the introduction between them of the hot air blast from said nozzle.
Claim 7
Dependent Claim
55 words
Apparatus as claimed in claim 5 wherein the nozzle has a flattened end arranged to be positioned between said longitudinal edge portions of the web and holes formed in the flattened end, hot air being directed against the adjacent surfaces of said longitudinal edge portions through the holes in the flattened end of the nozzle.
Claim 8
Dependent Claim
37 words
Apparatus as claimed in claim 6 wherein the nozzle is movable towards and away from said longitudinal edge portions to enable its flattened end to be inserted between them at the commencement of a heat sealing operation.
Claim 9
Dependent Claim
23 words
Apparatus according to claim 1 comprising a plurality of bypasses, each passing a different amount of gas, connected in parallel with the heater.
Claim 10
Dependent Claim
36 words
Apparatus according to claim 8 wherein said means for controlling said valve means for controlling the flow of gas through selected ones of said bypasses as a function of the speed of formation of the tube.
Claim 11
Dependent Claim
62 words
Apparatus as claimed in claim 1 wherein the heater is in the form of a multi-cored ceramic heater block the cored holes in which contain electric heater elements, and means is provided to adjust the electric current supply to the electric heater elements in response to signals derived from a temperature sensing element exposed to the hot air leaving the heater block.
Claim 12
Dependent Claim
36 words
Apparatus as claimed in claim 1 wherein each of said valve means has open and closed positions to open and close the respective bypasses and the valve means all pass different amounts of air when open.
Claim 13
Dependent Claim
18 words
Apparatus according to claim 1 wherein said longitudinal seam is arranged so as to form a ''''fin seal.''''
Claim 14
Independent Claim
133 words
A method of heating sealing a longitudinal seam of a continuously formed tube at a fixed heat sealing station using hot gas comprising passing the gas, at a regulated pressure, through a heater; selectively bypassing predetermined quantities of said gas around said heater through at least one bypass; directing the output gas from the heater and from said at least one bypass onto selected portions of said tube; controlling the heat input of the heater as a function of the temperature of the gas leaving the heater; controlling said at least one bypass to control the proportion of gas bypassing the heater as a function of the speed of formation of the tube, whereby the seam is heated to a required level regardless of its speed of travel through the heat sealing station.
Claim 15
Independent Claim
133 words
A method of heating sealing a longitudinal seam of a continuously formed tube at a fixed heat sealing station using hot gas comprising passing the gas, at a regulated pressure, through a heater; selectively bypassing predetermined quantities of said gas around said heater through at least one bypass; directing the output gas from the heater and from said at least one bypass onto selected portions of said tube; controlling the heat input of the heater as a function of the temperature of the gas leaving the heater; controlling said at least one bypass to control the proportion of gas bypassing the heater as a function of the speed of formation of the tube, whereby the seam is heated to a required level regardless of its speed of travel through the heat sealing station.
Claim 16
Dependent Claim
19 words
A method according to claim 13 wherein said at least one bypass is connected in parallel with said heater.
Claim 17
Dependent Claim
43 words
A method according to claim 13 comprising a plurality of bypasses, each bypass passing different amounts of gas, and selectively bypassing predetermined quantities of said gas through selected ones of said bypasses as a function of said speed of formation of tHe tube.
Claim 18
Dependent Claim
19 words
The method according to claim 13 wherein said longitudinal seam is arranged so as to form a ''''fin seal.''''
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |