US 3521425 A
Description (OCR text may contain errors)
July 21., 1970 v. E. PALM-ER 3,521,425
WRAPP NG METHOD AND APPARATUS I FQed May 24, 1967 5 Sheets-Sheet 1 INUENTOR V16 70/ E. Pam 2E? ATTORNEYS July 21, 1970 v.5. PALMER WRAPPING METHOD AND APPARATUS 5 Sheets-Sheet 2 Filed Jay 24, 1967 I \NVENTOE v'la r02 E. Pa MEE July 21, 1970 v. ELPALMER 3,521,425
WRAPPING umnon AND APPARATUS Filed May 24, 1967 I 5 Shets-Sheet 5 \NVENT R- $14M, m (mv 429M ATT'O ENEY9 V/c role 5. PQLME)? j 1;: 1 970 v; E. PALMER 3,521,425
. [WRAPPING um'rnon AND APPARATUS Filed May 24, 1967 5 Sheets-Sheet 4 \NVENTOE (/14 T02 E. 294M152 July 21, 1970 v. E. PALMER 3,521,425
WRAPPING METHOD AND APPARATUS Filed May 24, 1967 5 Sheets- Sheet 5 \NVENTOZ l/ILTOZ. E. PAM/W58 BY m, w mwzw Y5 J AT TO ENE United States Patent 3,521,425 WRAPPING METHOD AND APPARATUS Victor E. Palmer, Greendale, Wis., assignor to Wrapping Machinery Company, Inc., Franksville, W1s., a corporation of Wisconsin Filed May 24, 1967, Ser. No. 640,876 Int. Cl. B65b 67/10, 11/48 US. Cl. 5333 18 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to a package wrapping method and apparatus adapted to wrap articles in soft or shrink film drawn from a roll. There is an article prewrap table spaced above a conveyor table and offset rearwardly from its input end to expose a landing space thereon. An operator partially hand prewraps the article on the prewrap table and transfers it from the prewrap table to the input end of the conveyor table. In the course of this transfer, the partially wrapped article is swept past a hot wire to sever the film web, without lost motion on the part of the operator. The operator handles the partially wrapped package by grasping laterally extending film wings on which the operator can exert pressure to tension the film about the article.
BACKGROUND OF THE INVENTION It is old to associate a prewrap table in line with the conveyor of a semiautomatic wrapping machine, as shown, for example, in US Pat. 2,917,886, which is primarily intended for use in wrapping articles in precut square sheets of cellophane film. After the introduction of soft thermoplastic heat shrinkable films, it became common to draw a web of such film from a supply roll and to hand wrap an article therewith. In the course of this hand wrapping procedure, the length of film used in wrapping the article is severed from the roll. The wrapped package may then he carried away from the operator on a conveyor. If the film is heat shrinkable, the package may be conveyed through a heat shrink tunnel to shrink the film about the article to produce a neat, tightly wrapped package.
SUMMARY OF THE INVENTION In accordance with the present invention, a prewrap table, supply rolls for continuous webs of film, a conveyor table and underfolder are so organized and associated with respect to one another as to facilitate the wrapping operation and achieve greater output with less manual effort than has heretofore been possible in hand wrapping articles with film drawn in a continuous web from a supply roll. Increased efficiency and greater speed with reduced manual effort is achieved in the present invention by locating the prewrap table in spaced relation above the conveyor table and offset rearwardly from the input end thereof to expose a landing space to which the partially wrapped article is transferred in an easy motion of the operator. A web of film from the supply roll is trained beneath the prewrap table and into a space between the 3,521,425 Patented July 21, 1970 operator and the article on the prewrap table. The operator draws a length of film web upwardly into that space and thence folds the web partially about the article. The operator then grasps laterally extending film wings and uses them as handles to pick up the partially wrapped article and start to transfer the article toward the input end of the conveyor. As he draws the article toward himself in the same natural movement which will deposit it on the input end of the conveyor table, an additional length of film web is drawn from the supply roll, and the film web is swept across a severing tool, such as a hot wire, to sever the length from the web. This leaves the cut end of the web readily accessible for the next wrapping operation.
In a continuation of movement aforesaid, the operator deposits the partially wrapped package on the input end of the conveyor table and manually folds downwardly the laterally extending film wing portions thereof. This gives the operator a good purchase to impose lateral tension on the film. The operator then moves the package forwardly to actuate a control which starts the conveyor to move the package past underfolders which fold the wings up against the bottom of the package to complete the wrapping thereof. The conveyor desirably transfers the package to subsequent processing apparatus, such as a hot sealing belt and/or shrink tunnel which will snug the film about the package.
The invention resides in both the apparatus exemplified in the instant disclosure and in the method by which the operator processes a package through the novel wrapping steps herein disclosed.
DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation, partly in section, of apparatus embodying the present invention.
FIG. 2 is a fragmentary perspective view of the prewrap table and a portion of the conveyor table, other portions being broken away to expose details of construction.
FIG. 3 is a fragmentary perspective viewed from the tail end of the conveyor table to show details of the underfolder, the prewrap table being removed to expose de tails of construction.
FIG. 4 is a front fragmentary perspective viewed from the input end of the conveyor table, the prewrap table being removed to expose details of construction.
FIG. 5 is an enlarged fragmentary, but detailed vertical cross section taken along the line 55 of FIG. 4.
FIG. 6 is a cross section taken along the line 66 of FIG. 5.
FIG. 7 is a fragmentary vertical cross section taken through the longitudinal medial plane of the apparatus and showing the guides about which the film webs are trained beneath the prewrap table.
FIG. 8 is a fragmentary front elevation viewed in the direction of arrows 88 in FIG. 7 and showing details of the hot wire web severing tool and the guard and retainer rods adjacent thereto.
FIG. 9 is an enlarged detail of a portion of the apparatus shown in FIG. 7.
FIGS. 10 through 16 are diagrammatic views illustrating the Wrapping in sequence and in which:
PIC}. 10 shows the method step in which the film web is first drawn upwardly between the operator and the article on the prewrap table.
FIG. 11 shows the film web swung away from the operator and partially around the article on the prewrap table.
FIG. 12 shows the article after it has been picked up by the operator and pulled away from the prewrap table and toward the input end of the conveyor table and in the course of which an additional length of web is drawn from the supply roll.
FIG. 13 is a fragmentary plan view taken along the line 13-13 of FIG. 12 and showing how the operator grasps the laterally projecting film wings on the partially wrapped package and uses the film wings as handles to transfer the package and tension the film.
FIG. 14 shows the package in the course of being swept downwardly past the hot wire, thus to sever the partially wrapped length of film from the web and deposit the package on the input end of the conveyor table.
FIG. 15 shows how the operator manually folds the laterally projecting film wings to a taut downwardly inclined position and exerts a tensioning pressure on the wings.
FIG. 16 shows how the operator manually advances the package on the conveyor table slide rails to move the wings into a slot between the slide rails and retaining rails until the package engages the conveyor control lever to actuate the conveyor.
FIG. 17 is a simplified electric schematic circuit diagram of the control circuit for the conveyor.
DESCRIPTION OF THE PREFERRED EMBODIMENT Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structure. The scope of the invention is defined in the claim appended hereto.
The invention will be described primarily in terms of the apparatus, with interspersed reference to the method, both of which will be clear to those skilled in the art.
The wrapping apparatus is desirably mounted on a port-able dolly or cart 20 having castered legs 21 by which it can be advantageously located in a supermarket or the like, where articles 22 are to be wrapped in transparent soft or shrink film. As described in US. Pats. 2,917,886 and 3,045,406, the articles 22 typically comprise pallets or trays of cut meat or other food items which are to be displayed in display cases in a self-serving food market.
At its end near operator 23, cart 20 supports a conveyor table frame 24 on which a prewrap table 25 is elevated on legs 26, 27. The prewrap table 25 has its rear end somewhat elevated with respect to its front end so that the table 25 is inclined or slanted downwardly toward operator 23 to facilitate the wrapping operation. In the disclosed embodiment, the inclination is in the range of fifteen to twenty degrees to the horizontal. Prewrap table 25 is spaced sufficiently above a conveyor table 28 to pass wrapped articles 22 therebetween. The prewrap table 25 is offset rearwardly from the input end 31 of the conveyor table 28 to expose a landing space at its input end 31 between the opera-tor 23 and table 25, as shown in FIGS. 1 and 14.
Prewrap table 25 is supported on relativley deep side plates 32 which are widely spaced laterally at the sides of the conveyor table 28, as shown in FIG. 2. Film guide roller assemblies 34, 35, 36, 37, 38, 39, 40 span laterally from one plate to the other. Each film guide roller assembly 34-40, inclusive, desirably consists of a central rod and a roller sleeve fitted loosely on the rod to turn under pressure of the film thereacross.
Plates 32 provide anchorage for upwardly extending bracket arms 42 which support laterally spaced bearing bars 41 for a series of transparent rolls 43, 44, 45 of wrapping film. It is desirable to accommodate for several different specific types and gauges of film so that the operator has a choice of film best suited to wrap specific articles 22. Generally speaking, film rolls 43, 44, 45 consist of PVC thermoplastic film or variations thereof known in the trade as soft or shrink film.
Respective film webs 46, 47, 48 from the rolls 43, 44, 45 will be trained about the guide rollers 34-40, inclusive, as illustrated in FIG. 7. Fabric spacing aprons 51, 52 desirably define film web lanes and isolate one film web from contact with another.
The web of the film selected for use by the operator, for example, web 46 of film roll 43, is drawn around additional guides 33, 53, 54 and 55 to dispose the leading transverse edge of the web 46 in a position where it can be easily grasped by the operator 23 to initiate the process of prewrapping an article 22. The leading edges of the webs 47, 48 which are not in use are held in stored position by retainers 57.
At their leading front margins, and adjacent the path of transfer of the article 22 from table 25 to the input end 31 of conveyor 28, side plates 32 carry a transverse hot wire 59. Hot wire 59 is stretched taut and is held at its ends on spring leaves 60 which are mounted on terminal blocks 58 fastened to the plates 32. Wiring 61 connects to the terminal blocks 58 to heat the wire 59 electrically for the purpose of severing the thermoplastic film webs when a web is touched in contact with the wire. While the hot wire is preferred, it is but one example of severing tool that can be used to cut the web.
Immediately ahead of the hot wire 59 is a transverse guard bar 64 supported from the side plates 32 on end brackets 65. Guard bar 64 is a safety device to keep the operator 23 from inadvertently touching the hot wire.
Guide 54 coacts with guide 53 to function as an antibacklash brake to hold the severed end of web 46 from retraction after it has been cut. Guide rod 54 has rollers 49 which bear on cross rod 53. The ends of rod 54 are free to move vertically in slots 50 formed in end brackets 62 (FIG. 9) by which the rod 54 is supported from the table 25. Gravity biases the rod 54 and rollers 49 to exert light clamping pressure on the web 46 and against rod 53.
Conveyor table 28 and associated underfolders are generally similar to those shown in US. Pat. 3,045,406 and 3,016,671. As best shown in FIGS. 3, 4 and 6, there is a longitudinally extending channel-shaped track 66 over which passes the upper run of conveyor chain 67. Chain 67 is provided with spaced pusher lugs 68' which will push the packages along rails 71, 75 adjacent the track 66 when the chain is driven.
At its input end 31, the conveyor table comprises laterally exposed spaced side rails or tracks 71 and the end of track 66 on which a partially wrapped package 22 lands in the course of transferring it from prewrap table 25, as is indicated in FIGS. 3 and 14. Rails 71 are laterally unobstructed at the input end 31 of the conveyor table 28 so that the laterally extending film wings 108 of the partially wrapped article 22 can be manually swung in an arc to a downwardly inclined position, as is indicated in FIGS. 3 and 15.
Rearwardly offset from the input end 31 of conveyor table 28, each side rail 71 coacts with a guide rod or rail 72 which extends along the outside of side rail 71 and defines therebetween a slot into which the downturned wings 108 of the package are received when the operator manually advances the package from its position shown in FIG. 15 to its position shown in FIG. 16.
As in the prior patents aforesaid, conveyor table rails 71 have tapered end portions 73 which coact with correspondingly tapered end portions 74 of complementary conveyor table rails 75. These parts comprise an underfolding mechanism defining between the respective tapered end portions 73, 74 an oblique slot 76 through which the film wings 108 pass in the course of being underfolded against the bottom of the package 22. As in the prior Pat. 3,016,671 aforesaid, spring pressed elongated guide shoes 77 are mounted adjacent the rails 71, 75 to hold the package against the rails 71, 75 and guide it in its longitudinal movement along the conveyor table 28 under pressure of the conveyor chain lug 68. Shoes 77 have leaf springs 78 on which the shoes 77 may yield obliquely upwardly under pressure of the package. Springs 78 are mounted on adjustable brackets 81, as in the prior Pat. 3,016,671 aforesaid. The side rails of the conveyor table are laterally adjustable to accommodate different width packages, as in the prior patents aforesaid.
Still further underfolding of the wings 108 is accomplished by the converging plow blade plate 82 which define a V-notch to fold the wings 108 upwardly into contact withthe package bottom. At the end of the conveyor table 28 there is a roller 83 over which the package rolls onto a traveling belt 84. Belt 84 is supported on an apron plate 85 which is heated to transmit heat to the underfolded wings 108 and fuse the wings to the film at the bottom of the package. Beyond the plate 85 there may be a shrink tunnel 86 (FIG. 1) through which the package travels, if the film is heat shrinkable. This will snug the wrapper film about the package.
In order to exert some down pressure on the package 22 as it travels over the heated apron plate 85, one or more axially aligned pressure sponge rollers 87 are swingably mounted over plate 85 on the swing arms 88. Arms 88 carry a transverse axle 89 on which sponge rollers 87 turn as driven by belt 80 as the package travels therebeneath. Belt 80 is driven by the same power train 79 vthat drives belt 84 from motor 70. The weight of the rollers 87 adds to gravity to press the underfolded wings 108 into intimate contact with the belt 84 and heated plate 85.
Rollers 87 are kept spaced from the belt 84 even when I there is no package 22 therebeneath by a suspension frame including side legs 92 which carry a cross bridge 93 from which depends a central stem 94. Stem 94 has two collars 91, either one of which is selectively engaged with hanger yoke 90 to adjust the height at which the rollers are hung.
Swing arms 88 have upstanding arms 95 with a cross connecting bridge 96 having a lateral support eye 97 slideably related to the stem 94. The bottom of the stem 94 has a cross pin 98 which defines the lower limit of movement of the eye 97. However, eye 97 can ride up on the stem 94 under the upward pressure of a package therebeneath. Accordingly, the powered rollers 87 can be set at various heights spaced above belt 84 to admit various height packages therebeneath. The rollers 87 yield upwardly to pass the package.
The novel wrapping method is illustrated diagrammatically in FIGS. 10 through 16. The operator selects one of the film rolls 43, 44, 45 as appropriate for wrapping article 22 which come to the operators station in a series on another conveyor, in a bin or the like. In this illustration roll 43 having web 46 is selected. An article 22 from the series is manually placed on table 25 with its lower end braced against positioning abutment flange 103. The table is also provided with an adjustable elevating support block 104 on which the rear edge of the package 22 is elevated above the table 25. The operator grasps the side margins of Web 46 which are between support rods 53, 55 and draws the web 46 upwardly in the direction of arrow 105 through the space which exists between the operator 23 and the prewrap table 25. This is also shown in FIG. 1.
A sufiicient length of the web 46 is drawn beyond cross rod 53 so that it may be swung forwardly toward the prewrap table 25, as shown in FIG. 11, to go around the far end of the article 22 and be tucked therebeneath, as indicated by the arrow 107 in FIG. 11. This motion creates lateraly extending wing portions 108 of the film,
6 as is indicated in FIG. 13. The operator grasps wings 108 with his hands 111 and uses the wings 108 as handles in manipulation of the package during the next following sequences of the method. The operator also exerts lateral pull on the film to tension it laterally.
As shown in FIGS. 12 and 13, the operator then picks up the partially wrapped article 22 utilizing the wings 108 as handles and draws the article toward himself. In the course of this movement of the article 22 in the direction of arrow 112, an additional length of the film web 46 is drawn from its parent roll 43 and beyond cross rod 53 until the package reaches substantially its position shown in FIG. 12. The operator then swings or lowers the package downwardly toward the input end 31 of the conveyor table and in the direction indicated by the arrow 113 in FIG. 14.
This motion will sweep the film web 46 against the hot wire 59 to sever the web transversely across its length. The package continues its downward movement to its landing place on the rails 71 and conveyor track 66 at the input end 31 of the conveyor table 28, as shown in full lines in FIG. 14.
The severed leading edge of the web 46 will retract slightly from the hot wire 59 and will remain adhered to the laterally exposed cross member 55, where it is readily available for the next wrapping operation, this condition being also shown in FIG. 7. Cross member 55 comprises means positioned between the hot wire and the table to hold the severed leading edge of the web in a position ahead of the table. Cross member 55 desirably consists of a plastic tube to which the film tends to adhere.
As thus far described, it is clear that the article 22 has been partially hand prewrapped in a simple continuous sweep motion of the operators arms on a generally circular path near the termination of which the package is swept past the hot wire 59 to sever the web in the course ,of its transfer from the prewrap table 25 to the input end 31 of the conveyor table 28. The transfer motion is in a generally downward and rearward direction requiring minimum effort on the part of the operator and substantially no lost motion.
An important advantage of the foregoing sequence is that at the completion of the hand prewrap sequence, the package 22 is on the input end 31 of the conveyor table 28 in readiness for further movement without the operator having to transfer the package to another conveyor, etc. Moreover, the package is advantageously located so that the operator has good purchase to exert down pressure on the package wings 108 to tension the film and fold the wings about the laterally open rails 71 to a downwardly inclined position suitable for further action thereon by the underfolders.
At this point in the sequence, the chain conveyor 67 is inactive, both switches and 124 in the electric circuit of FIG. 17 being open. The operator now advances the package manually forwardly on the conveyor table 28 from its position shown in FIG. 15 to its position shown in FIG. 16 in the course of which the package 22 engages a control lever 114 for a microswitch 115 (FIG. 5) which is in the circuit ot an electric clutch 117 by which drive motor 118 is coupled to a drive chain 119 (see FIGS. 1 and 17). When the clutch 117 is energized in consequence of the package tripping the control lever 114, chain 119 will drive chain 67 through sprocket drive 110, thus to advance a pusher lug 68 against the rear of the package, and mechanically convey the package along the conveyor table 28 and underfold the wings 108 beneath the package 22 as hereinbefore described. By the time the conveyor chain 67 has advanced far enough to move the package 22 off of control lever 114, thus to open switch 115, cam 122 (FIG. 1) has closed parallel switch 124 to hold closed the circuit to the clutch 117, as shown in FIG. 17.
The conveyor chain 67 will remain in motion until the package has been discharged onto the belt 84 at which 7 time cam 122 will act on lever 123 for control switch 124 (FIG. 1) to open switch 124, deenergize the clutch 117 and stop the chain. Clutch 117 is now in readiness for reenergization when the next package is moved forwardly to engage control lever 114.
As the operator moves the package 22 manually from its position shown in FIG. 15 to its position shown in FIG. 16, the wings 108 will pass into the slot between the side rails 71 and the retaining or guide rails 72 so that the operator can release his manual grip on the wings 108 without their becoming disoriented.
In some embodiments the conveyor chain 67 can be continuously driven. The operator will time his prewrap and transfer motions to synchronize with the chain motion to insure delivery of the prewrapped articles to the conveyor table 28 in time therewith.
1. Apparatus for hand prewrapping an article in film drawn from a film web supply roll and conveying it therefrom, said apparatus comprising a conveyor, a conveyor table and means to move the conveyor along the table, a prewrap table spaced above said conveyor table and offset beyond the input end of the conveyor table to leave landing room for the article on the input end of the conveyor table and a space beneath the prewrap table through which the article is moved by the conveyor, and a transverse web severing tool between the prewarp table and the input end of the conveyor table and in the path of transfer from the prewarp table to to the input end of the conveyor table and against which the web is swept to sever the web in the course of said transfer.
2. The apparatus of claim 1 in which said severing tool comprises a hot wire.
3. The apparatus of claim 1 in which there are guides beneath the prewrap table and along which said Web is trained to dispose its leading edge in the space between the prewarp table and the input end of the conveyor table where it is readily accessible to an operator to draw the web from the supply roll in the course of prewrapping the next article.
4. The apparatus of claim 1 in which said prewrap table has a package rest on which the rear edge of the article is elevated to leave room to receive the leading edge of the Web so it is wrapped thereabout.
5. The apparatus of claim 1 in which the input end of the conveyor table has laterally open rails around which film wings laterally extending from the package are drawn to a generally downward inclination after the article lands on said input end, and wing underfolders along said conveyor table beyond its said input end and by which said film wings are folded beneath the package in the course of its movement along said conveyor table.
6. The apparatus of claim 5 in which there is a heat seal surface to which said package is conveyed by the conveyor to seal the underfolded film wings.
7. The apparatus of claim 5 in which the conveyor has a control beyond said input end and which is engaged by manual movement of the package along the conveyor table.
8. The apparatus of claim 7 in which there are wing retaining rails beyond said input end and adjacent which the film wings are slid in the course of moving the packages toward said control.
9. The apparatus of claim 5 in which there is a heat seal surface to which the package is conveyed by the conveyor to seal the underfolded film wings, and a presser roller to press the package against said surface.
10. In a wrapping method in which an article is manually prewrapped at a prewrap table to a partially wrapped condition in which film wings extend laterally from the article and the article is transferred to a conveyor table having laterally open side rails and along which underfolding apparatus is disposed, the improvernent in which an operator located at the end of the conveyor table and in alignment with the rails manually transfers the partially wrapped article to an input end of the conveyor table by grasping respective extending wings with his respective hands and using the wings as handles for the article, draws the article toward himself, deposits the article on said input end and moves his hands downwardly at each side of the rails to manually fold the wings to a generally down ward inclination about said side rails for subsequent motion away from the operator for action thereon by said underfolding apparatus.
11. The wrapping method of claim 10 in which the operator exerts lateral tension on the film by pushing the wings downwardly about said rails.
12. The wrapping method of claim 10 in which the operator also manually advances the package along said side rails by pushing forwardly on said wings to actuate a conveyor control and then releases his grasp on said wings to permit the conveyor to move said package past the underfolding apparatus.
13. A wrapping method in which an operator successively hand prewraps a succession of articles on a prewrap table with film drawn from a film web supply roll, severs the web on a transverse severing tool and transfers the hand prewrapped article to a conveyor table on which the article travels beneath the prewrap table, and including the steps of positioning the article on the table in spaced relation to the operator, drawing a length of web from the roll on a path beneath the table and upwardly through said space, folding the withdrawn web length away from the operator and partially about the article, moving the article from the table toward the operator to remove it from the table and at the same time withdraw an added length of web from the roll, moving the article downwardly toward the conveyor table in the course of which movement the article is swept past the tool to sever said web and moving the article along the conveyor table beneath the prewarp table and through the space between said tables.
14. A wrapping method in which an operator successively hand prewraps a succession of articles on a prewrap table with film drawn from a film web supply roll, severs the web on a transverse severing tool and transfers the hand prewrapped article to a conveyor table on which the article travels beneath the prewrap table, and including the steps of positioning the article on the table in spaced relation to the operator, drawing a length of web from the roll on a path :beneath the table and upwardly through said space, folding the withdrawn web length away from the operator and partially about the article, moving the article from the table toward the operator to remove it from the table and at the same time withdraw an added length of web from the roll and moving the article downwardly toward the conveyor table in the course of which movement the article is swept past the tool to sever said web, the movement of the article from the prewrap table being accomplished by the operators grasping laterally extending film wings formed by folding the web partially about the article on the prewrap table and using these wings as package handles.
15. The method of claim 14 in which said wings are folded down manually at the sides of the conveyor table after the article is placed thereon.
16. The apparatus of claim 1 in which there is a cross member between said web severing tool and the prewarp table, said cross member comprising plastic to which the film tends to adhere and toward which the severed leading edge of the web will retract and adhere to be available in a position ahead of the table for the next wrapping operation.
17. Wrapping apparatus comprising a prewrap table, a source of plastic wrapping film which is drawn in the form of a web in the course of prewrapping an 2,954,654 10/1960 Arvidson 53206 X article on the table, a web severing tool beyond the 3,176,443 4/1965 Klamp 53--390 table and means positioned between the tool and the 3,263,392 8/1966 Petrella et al 53390 X table to hold the severed leading edge of the web in 3,298,265 1/1967 Millican et a1 53--390=X a position ahead of the table to be available for the next 5 3,043,071 7/ 1962 Sadell 53-390 wrapping operation, said means comprising a laterally 3,381,449 5/1968 Vaughan 53390 exposed plastic cross member to which the film will adh FOREIGN PATENTS 18. The apparatus of claim 17 in which the web sever- 939,306 10/1963 Great Britain ing tool comprises a hot wire. 0
THERON E. CON-DON, Primary Examiner References Cited N. ABRAMS, Assistant Examiner UNITED STATES PATENTS 2,346,613 4/1944 Rumsey 53 217 X US. 01. X.R. 2,725,699 12/1955 Rumsey s3-219 15 2 6, 388, 390 2,926,473 3/1960 Byland.