Patent US3897671A successfully refreshed from Google Patents.
US3897671A
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Apparatus and method for covering a load on a pallet
Assignee: COMPTEX Inc
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Filing: 1973-08-31
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Granted: 1975-08-05
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Expires: 1993-08-31
Abstract
Abstract A load on a pallet covered with an inverted bag with heat shrinkable film is moved through a shrink tunnel. Air is withdrawn from the bag by a venting system that follows the movements of the bag in the tunnel. The air is withdrawn from the bag with sufficient negative pressures to cause the lateral skirts of the bag, which depend below the pallet, to fold against the pallet bottom for heat shrinkage in that position so as to anchor the bag to the pallet.
Inventors
- 👤 David M Higgins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:05
CPC Classifications
B; B65; B65B; B65B53/00; B65B53/02; B65B53/06; B65B53/063
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
174 words
A method of covering a load on a pallet comprising the steps of: placing an inverted bag of heat-shrinkable film over the load on the pallet, said bag of film having a length greater than the combined height of the load and pallet so that a skirt of film depends below the pallet, supporting the pallet with the sides of the pallet and the depending skirts of film laterally beyond the supporting structure, moving the pallet through a heat-shrinkage area and heat-shrinking the heat-shrinkable film, withdrawing air from the lower end of the bag with sufficient negative pressures while moving the pallet and load through the heat-shrinkage area so as to cause the depending lateral skirts of film to fold under the pallet sides and to be secured under the bottom of the pallet during at least a portion of the movement through said heat-shrinkage area, and controlling the withdrawal of air to sequentially apply negative pressures toward the lower end of the bAg to follow the pallet and load through the heatshrinkage area.
Claim 2
Independent Claim
174 words
A method of covering a load on a pallet comprising the steps of: placing an inverted bag of heat-shrinkable film over the load on the pallet, said bag of film having a length greater than the combined height of the load and pallet so that a skirt of film depends below the pallet, supporting the pallet with the sides of the pallet and the depending skirts of film laterally beyond the supporting structure, moving the pallet through a heat-shrinkage area and heat-shrinking the heat-shrinkable film, withdrawing air from the lower end of the bag with sufficient negative pressures while moving the pallet and load through the heat-shrinkage area so as to cause the depending lateral skirts of film to fold under the pallet sides and to be secured under the bottom of the pallet during at least a portion of the movement through said heat-shrinkage area, and controlling the withdrawal of air to sequentially apply negative pressures toward the lower end of the bAg to follow the pallet and load through the heatshrinkage area.
Claim 3
Dependent Claim
47 words
The method of claim 1 which further includes the step of folding the depending skirt at the front end under the pallet and holding the front end skirt in folded position through at least a portion of the heat shrinking operation in order to form such securement.
Claim 4
Dependent Claim
47 words
The method of claim 1 which further includes the step of folding the depending skirt at the rear end under the pallet and holding the rear end skirt in folded condition during at least a portion of the heat shrinking operation in order to form such securement.
Claim 5
Dependent Claim
30 words
The method of claim 1 in which said withdrawal of air from the bag continues during movement of the pallet during at least a portion of the heat shrinking operation.
Claim 6
Dependent Claim
28 words
The method of claim 1 wherein the withdrawal of air from the bag occurs before the bag of heat-shrinkable film reaches a weld temperature to collapse the bag.
Claim 7
Independent Claim
90 words
A method of covering a load on a pallet with heat-shrinkable film, the steps comprising: moving an inverted bag of heat-shrinkable film over the load on the pallet through a heat-shrinkage area and heat-shrinking the heat-shrinkable film, venting the inverted bag with a movable venting system, said venting system providing negative pressures within the bag, and moving said venting system so as to follow said moving pallet and load and control the venting to sequentially apply negative pressures within the bag during at least a portion of the heatshrinking operation.
Claim 8
Independent Claim
90 words
A method of covering a load on a pallet with heat-shrinkable film, the steps comprising: moving an inverted bag of heat-shrinkable film over the load on the pallet through a heat-shrinkage area and heat-shrinking the heat-shrinkable film, venting the inverted bag with a movable venting system, said venting system providing negative pressures within the bag, and moving said venting system so as to follow said moving pallet and load and control the venting to sequentially apply negative pressures within the bag during at least a portion of the heatshrinking operation.
Claim 9
Dependent Claim
41 words
The method of claim 6 wherein the bag of film has a skirt depending below the pallet and air is withdrawn from the bag so that the side flaps of said skirt are folded below the pallet bottom with air pressures.
Claim 10
Dependent Claim
32 words
The method of claim 7 wherein at least one end flap is folded below the pallet bottom and the side flaps are fused to said end flap during the heating shrinking operation.
Claim 11
Dependent Claim
21 words
The method of claim 7 wherein the venting of the inverted bag occurs before the heat-shrinkable film reaches a weld temperature.
Claim 12
Dependent Claim
118 words
Apparatus for shrinking an inverted bag of heat-shrinkable film upon a loaded pallet comprising: support means for the loaded pallet with a skirt of the film depending below the bottom of the pallet, heating means in an area for heating the exterior of the bag, means for moving the loaded pallet enveloped in the inverted bag with the depending skirt through the said heating area, duct means below the pallet for withdrawing air from the inverted bag to produce negative pressures therein, said duct means including air directing means to sequentially apply negative pressures beneath the moving pallet, and means for moving said air directing means to follow the pallet as it moves in said heating means area.
Claim 13
Dependent Claim
118 words
Apparatus for shrinking an inverted bag of heat-shrinkable film upon a loaded pallet comprising: support means for the loaded pallet with a skirt of the film depending below the bottom of the pallet, heating means in an area for heating the exterior of the bag, means for moving the loaded pallet enveloped in the inverted bag with the depending skirt through the said heating area, duct means below the pallet for withdrawing air from the inverted bag to produce negative pressures therein, said duct means including air directing means to sequentially apply negative pressures beneath the moving pallet, and means for moving said air directing means to follow the pallet as it moves in said heating means area.
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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) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |