US3762853A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cooling means for tubular plastics film extruded in the form of a bubble through an annular nozzle orifice
Assignee: Windmoeller and Hoelscher KG
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Filing: 1971-06-29
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Granted: 1973-10-02
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Expires: 1991-06-29
Abstract
Abstract In a blowhead for making tubular plastics film by extruding a tubular film bubble through a nozzle orifice, interior air cooling and inflating means for the bubble comprise an air inlet passage extending axially through the blowhead, an air outlet tube which is disposed centrally through the inlet passage, projects into the bubble with one end and has a suction fan connected to its other end, a first guide ring around the outlet tube for directing air from the inlet passage onto the bubble wall, and at least one additional guide ring downstream of the first ring and disposed around the outlet tube at a spacing therefrom to define an annular aperture through which some of the air can flow further into the bubble.
Inventors
- 👤 H Upmeier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 05:48
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/88; B29C48/885; B29C48/03; B29C48/09; B29C48/10; B29C48/89; B29C48/911; B29C48/9115; B29C48/912
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
153 words
A blowhead for tubular plastics film, comprising an annular nozzle orifice for forming a tubular film bubble, an inlet passage extending axially of said nozzle orifice and adapted to introduce interior cooling and inflating air into said bubble, an air outlet tube disposed centrally of said inlet passage and projecting into said bubble, suction means operatively connected to said outlet tube, a first guide ring for said interior cooling air, said first guide ring surrounding said outlet tube and adapted to direct said interior cooling air from said inlet passage onto the inside of the bubble wall adjacent to said nozzle orifice and at least one additional guide ring for said interior cooling air disposed around said outlet tube and downstream of said nozzle orifice, said guide rings being axially spaced from one another and said at least one additional guide ring being provided near the outlet tube with an air flow aperture.
Claim 2
Dependent Claim
153 words
A blowhead for tubular plastics film, comprising an annular nozzle orifice for forming a tubular film bubble, an inlet passage extending axially of said nozzle orifice and adapted to introduce interior cooling and inflating air into said bubble, an air outlet tube disposed centrally of said inlet passage and projecting into said bubble, suction means operatively connected to said outlet tube, a first guide ring for said interior cooling air, said first guide ring surrounding said outlet tube and adapted to direct said interior cooling air from said inlet passage onto the inside of the bubble wall adjacent to said nozzle orifice and at least one additional guide ring for said interior cooling air disposed around said outlet tube and downstream of said nozzle orifice, said guide rings being axially spaced from one another and said at least one additional guide ring being provided near the outlet tube with an air flow aperture.
Claim 3
Dependent Claim
15 words
A blowhead according to claim 1, wherein said guide rings have substantially equal outside diameters.
Claim 4
Dependent Claim
26 words
A blowhead according to claim 1, wherein the outside diameter of each of said guide rings is substantially equal to the diameter of said nozzle orifice.
Claim 5
Dependent Claim
15 words
A blowhead according to claim 1, wherein the spacing between said guide rings is adjustable.
Claim 6
Dependent Claim
33 words
A blowhead according to claim 1, wherein said aperture in each of said at least one additional guide rings is bounded by said outlet tube and the internal circumference of said guide ring.
Claim 7
Dependent Claim
31 words
A blowhead according to claim 5, wherein there are at least two additional guide rings having successively larger air flow apertures in the direction of flow of the interior cooling air.
Claim 8
Dependent Claim
48 words
A blowhead according to claim 6, wherein the air flow through the aperture of one of said additional guide rings is separated from the air flow through the aperture of the other of said additional guide rings located downstream thereof by a tubular wall surrounding said outlet tube.
Claim 9
Dependent Claim
38 words
A blowhead according to claim 1 inlcuding a suction tube protruding into the inlet end of said outlet tube and operating on the jet pump principle and forming an extension of said outlet tube through the film bubble.
Claim 10
Dependent Claim
54 words
A blowhead according to claim 1, including an air supply pipe connected to the inlet end of said inlet passage, a throttle valve positioned in said air supply pipe, and wherein said suction means comprise a suction fan having surplus capacity and an auxiliary throttle valve provided in the suction line of said fan.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |