Claims
- 1. A method for wrapping an elongate load, conforming generally to a rectangular solid and having a front face, a back face, an elongate upper face, an elongate lower face, and two elongate lateral faces, with wrapping film from first, second, and third rolls, with said first and second rolls being rotatable about fixed, parallel axes, comprising the steps of:
- welding a length of film from said first roll, and a length of film from said second roll, to each other, by a first welding means, so as to form a predraped wall of film having a first welded seam in front of said load to be wrapped;
- conveying said load to be wrapped into said predraped wall, in a frontward direction, so as to cover said front face and two elongate faces of said load to be wrapped with film from said welded lengths of film;
- welding said welded lengths of film again to each other, by said first welding means, so as to form a second welded seam behind said covered load and thereby cover said back face of said load with film from said welded lengths of film;
- severing said welded lengths of film from said first and second rolls of film at a location near said second welded seam behind said covered load;
- conveying said covered load, having said first and second welded seams, further in said frontward direction relative to said third roll of film while wrapping a length of film from said third roll of film in a spiral pattern around said covered load and over said film covering said two elongate faces of said covered load so as to cover said elongate upper, lower, and lateral faces of said covered load with film from said third roll of film;
- welding said spirally wrapped film from said third roll of film to a portion of said welded lengths of film from said first and second rolls of film, by a second welding means, along one of said elongate upper, lower, and lateral faces of said covered load during conveyance of said covered load in said frontward direction; and
- severing said spirally wrapped film, welded to said portion of said welded lengths of film from said first and second rolls of film, from said third roll of film.
- 2. The method of claim 1, wherein:
- said elongate faces of said load which are covered with said film from said welded lengths of film from said first and second rolls are the upper and lower faces.
- 3. The method of claim 1 wherein the film lengths welded again to each other are welded so as to form two spaced, parallel, welded seams behind the load and are severed from the first and second rolls between the welded seams behind the load.
- 4. The method of claim 1 further comprising a step of
- perforating the film in areas along at least one of the elongate faces of the load while the load is being conveyed.
- 5. The method of claim 4 wherein the film is perforated so as to provide the film with generally V-shaped perforations pointing toward the front face.
- 6. The method of claim 4 wherein the film is perforated along both of the lateral faces.
- 7. The method of claim 6 wherein the elongate faces covered with film from the welded lengths of film are the upper and lower faces.
- 8. The method as set forth in claim 4, wherein:
- said covering of said load with said welded lengths of film from said first and second rolls of film is performed at a first predraping and wrapping station;
- said spiral wrapping of said load with said film from said third roll of film is performed at a second spiral wrapping station located downstream of said first predraping and wrapping station as viewed in said frontward direction; and
- said welding of said spirally wrapped film and said perforating of said film is performed at a third welding and perforating station located downstream of said second spiral wrapping station as viewed in said frontward direction.
- 9. Apparatus for wrapping an elongate load conforming generally to a rectangular solid and having a front face, a back face, an elongate upper face, an elongate lower face, and two elongate lateral faces, with wrapping film from first, second, and third rolls of film, comprising:
- means for mounting said first and second rolls of film so that said first and second rolls of film are rotatable about fixed, parallel axes, and so that film can be pulled from said first and second rolls of film;
- first means for conveying said load in a frontward direction;
- first means for welding a length of film from said first roll of film and a length of film from said second roll of film to each other so as to form a predraped wall of film, having a first welded seam disposed in front of said load to be wrapped, into which said load is moved by said first conveying means when said first conveying means moves said load to be wrapped in said frontward direction so as to cover said front face and two elongate faces of said load with film from said welded lengths of film; for welding said welded lengths of film again to each other so as to form a second welded seam behind said covered load and thereby cover said back face of said load with film from said welded lengths of film, as said first conveying means moves said load further in said frontward direction; and for severing said welded lengths of film from said first and second rolls of film at a location near said second welded seam behind said covered load;
- second means for conveying said covered load, having said first and second welded seams, in said frontward direction relative to said third roll of film;
- means for wrapping a length of wrapping film from said third roll of film in a spiral pattern around said covered load and over said film covering said two elongate faces of said load so as to cover said upper, lower, and lateral faces of said load with said film from said third roll of film;
- second means for welding said spirally wrapped film from said third roll of film to a portion of said welded lengths of film from said first and second rolls of film which cover said load along one of said elongate upper, lower, and lateral faces of said covered load and in a direction extending parallel to said frontward direction during conveyance of said covered load in said frontward direction; and
- means for severing said welded spirally wrapped film, welded to said portion of said welded lengths of film from said first and second rolls of film, from said third roll of film.
- 10. The apparatus of claim 9 wherein the first conveying means is operative for conveying the load into the predraped wall of film so as to cover the front, upper and lower faces with film from the welded lengths.
- 11. Apparatus as set forth in claim 9, wherein:
- said first welding and severing means comprises an anvil disposed upon one side of said load, and a welding and cutting head reciprocatingly disposed upon an opposite side of said load so as to be movable toward and away from said anvil in a direction substantially perpendicular to said frontward direction of movement of said load by said conveying means.
- 12. Apparatus as set forth in claim 9, wherein:
- said second welding means comprises a rotary drum having heating means defined within peripheral portions of said drum for engaging said lower face of said load as said load is conveyed by said conveying means in said frontward direction.
- 13. The apparatus of claim 9 further comprising
- means for perforating the film at locations along each lateral face while the load is being conveyed.
- 14. The apparatus of claim 9 further comprising
- means for perforating the film with generally V-shaped perforations, which point toward the front face of the load, at locations along each lateral face while the load is being conveyed.
- 15. The apparatus of claim 9 further comprising
- means for perforating the film at locations along at least one elongate face while the load is being conveyed.
- 16. Apparatus as set forth in claim 15, further comprising:
- means defining a first predraping and wrapping station at which said covering of said load with said welded lengths of film from said first and second rolls of film is performed;
- means defining a second spiral wrapping station, disposed downstream of said first predraping and wrapping station as viewed in said frontward direction, at which said spiral wrapping of said load with said film from said third roll of film is performed; and
- means defining a third welding and perforating station, disposed downstream of said second spiral wrapping station as viewed in said frontward direction, at which said welding of said spirally wrapped film and said perforating of said film is performed.
- 17. Apparatus as set forth in claim 15, wherein:
- said means for perforating said film comprises at least one perforating wheel having a plurality of perforating cutters and rotatably movable about an axis which is disposed perpendicular to said frontward direction.
- 18. Apparatus as set forth in claim 17, wherein:
- said plurality of perforating cutters are disposed upon said at least one perforating wheel in two alternating circumferential arrays.
- 19. Apparatus as set forth in claim 17, further comprising:
- spring biasing means for biasing said at least one perforating wheel into contact with said wrapped load so as to permit said plurality of perforating cutters to form perforations within said film wrapping said load.
- 20. Apparatus as set forth in claim 17, wherein:
- said at least one perforating wheel comprises two axially spaced perforating wheels.
- 21. Apparatus as set forth in claim 20, wherein:
- said plurality of perforating cutters are disposed upon each one of said two axially spaced perforating wheels in two alternating circumferential arrays.
- 22. Apparatus as set forth in claim 20, further comprising:
- spring biasing means for biasing said two axially spaced perforating wheels into contact with said wrapped load so as to permit said plurality of perforating cutters to form perforations within said film wrapping said load.
Parent Case Info
This application is a continuation of application Ser. No. 07/969,568, filed Oct. 30, 1992.
US Referenced Citations (19)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2448720 |
Apr 1975 |
DEX |
Continuations (1)
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Number |
Date |
Country |
Parent |
969586 |
Oct 1992 |
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