US2991823A - Band sealing device - Google Patents

Description

July 11, 1961 T. JENSEN ETAL 2,991,823

BAND SEALING DEVICE Filed May 16, 1958 4 Sheets-Sheet 1 INVENTORS THORMOD JENSEN t3? VuaGu. J. CLOCK July 11, 1961 T. JENSEN ETAL BAND SEALING DEVICE 4 SheetsSheet 2 Filed May 16, 1958 null! July 11, 1961 T. JENSEN ETAL 2,991,823

BAND SEALING DEVICE 4 Sheets-Sheet 5 Filed May 16, 1958 Q INVENTORS HORMOD JENSEN Vnaeu. J. CLOCK 13 flO/ Z M11,

ATTYS.

y 11, 1961 T. JENSEN ETAL 2,991,823

BAND SEALING DEVICE Filed May 16, 1958 4 Sheets-Sheet 4 g :i 1. i 8i "-7 "7- 9 a2 a8 58 9 8 84 2 A l n INvENToRs THORMOD JENSEN Vnzau. J. CLOCK ATTYS United States Patent C) This invention relates to improvements in a machine for sealing a printed band of fibrous material, such as waxed paper, to a wrapper of cellophane or the like.

In the wrapping of articles, such as loaves of bread, it is desirable to have the wrapper proper constructed of a transparent wrapping material, such as, cellophane or the like, and have a band, preferably of wax paper, adhesively united to the inner surface of the wrapper, the band usually being printed and encircling the bread loaf intermediate its ends.

In adhesively uniting the band to the wrapper it is sometimes desirable to adhesively unite the entire area of the band to the wrapper and at other times it is desirable to unite only the marginal portions of the band to the wrapper.

The present invention contemplates a band sea-ling device wherein both operations may be conveniently performed, the device being characterized in that the sealing or uniting operation can be performed rapidly, and will result in a wrapper wherein the sheets are securely, neatly and smoothly united together.

One of the features of the present invention resides in a machine for adhesively uniting the lateral edge portions of a web of band material to a web of wrapper material as a continuous operation, the machine comprising means for uniting the band to the central portion of wrapper or uniting said band to the wrapper offset laterally from the center of the wrapper in either direction.

Other objects, advantages and features of the present invention will be apparent from the accompanying drawings and following detailed description.

In the drawings,

FIG. 1 is a side elevational view of apreferred form of the band sealing machine.

I FIG. 2. is a top plan view of the device shown in FIG. 1.

' FIG. 3 is a transverse sectional view taken on line 3-3 of FIG. I.

' FIG. 4 is a transverse sectional view taken on line 4-4 of FIG. 1.

FIG. 5 is a transverse sectional view showing a modified form of heater head.

' .FIG. 6 is a side elevational view of a band sealing device having another modified form of heater head. FIG. 7 is a top plan view of the device shown in FIG.

6, looking in the direction of the arrows 7-7 in FIG. 6. FIG. 8 is a transverse sectional view taken on line '-8--8 of FIG. 6.

-FIG. 9 is a side elevational view of a wrapped loaf of bread wherein the band is centrally disposed relative to the .bread loaf and the wrapper.

' FIG. l0 is a view similar to that shown in FIG. 9 wherein the band is offset from the center of the loaf of bread and the wrapper.

Referring in detail to the drawings, 1 indicates one of a spaced pair of rods comprising a portion of the frame which supports a band sealing device 2 embodying the features of the present invention. The band sealing device 2 is supported from the spaced rods 1 by a pair of downwardly extending plates 3 which are secured at theirupper portions to the rods 1 by means of staples 4, the "arrangement being such that the plates 3 are longitudinally movable to desired positions along the length of the rods 1.

A supporting shaft 5 has its opposite end portions 6 carried by the opposite plates 3. As will be hereinafter more fully described, the rod 6 functions as a pivotal support for the frame of the band sealing device 2. The frame of the band sealing device comprises a spaced pair of bars 7 which are connected and spaced from each other by a transverse frame member 8 adjacent the rear end portions of said bars. The forward end portions of each of the bars terminate in angularly inclined upwardly extending arms 9. Between the end portions of the upwardly extending arms 9 a heating shoe 10 is positioned. The shoe 10 is of substantially semicylindr-ical shape and an electrical heating element 11 is positioned in an aperture in said shoe and functions to heat said shoe. The shoe 10 is also supported by a transverse brace 12' and is connected to screws 13, the ends of said brace being secured to the arms 9. -A conventional thermostat 14 is positioned adjacent the central portion of the shoe 10 and connects the heating element 11 with a source of electricity (not shown) which is conducted to the thermostat through a conductor 15. The thermostat 14 is provided with a control shaft 16 which carries a knob 17 whereby the thermostat may be adjusted to maintain the temperature of the shoe 10 at a desired degree.

Thus, the frame of the band sealing device 2 comprises a substantially rectangular rigid frame structure which is swingably associated with the shaft 5. A plate 18 is.

secured to the inner face of each of the bars 7 and said opposite plates carry spaced transverse bars 19 which are rigidly secured at their ends to the opposite plates 18. A transverse fulcrum pin 20 extends between the spaced bars 19 and rests upon the central portion of the shaft 5, collars 21 being positioned upon each side of the fulcrum pin 20 to prevent undesired lateral movement of the frame relative to the axis of the shaft 5.

The arrangement is such that the frame of the band sealing device is essentially supported by the fulcrum pin upon the shaft 5 whereby the frame may rock a limited degree about the longitudinal center of the shaft 5. Thus the frame of the band sealing device 2 is swingable about the axis of the shaft Sand is also roclkable in a plane transverse to the axis of the shaft 5. Adjacent plates 18 between the transverse members 19 are ball bearing assemblies 22 which facilitate the rocking movement of the frame and also the swinging movement of the frame relative to shaft 5'. The end portions of the shaft 5 extend through the opposite bars 7, said bars being provided with apertures which are enlarged relative to the diameter of the portions of the shaft which extend through said bars whereby the rockable movement about the fulcrum pin 20 is accommodated. The frame of the band sealing device carries a shaft 23 which in turn carries a core 24 upon which a roll 25 of fibrous web material is carried, thefibrous Web material usually comprising wax paper or the like when the band is to be used as part of a wrapping for bread. A Web 26 of the band material is drawn from the roll 25 and is carried over a guide roll 27. The guide roll 27 is carried upon a shaft 28 which rests in opposite slots 29 which are provided in the upper edges of the opposite plates 18.

The frame of the device also carries a shaft 30 which in turn carries a core 31 upon which a roll of wrapping material 32 is carried. The roll material 32 usually comprises a web of cellophane, polyethylene, or the like. As will be hereinafter more fully described, the function of the machine 2 is to adhesively unite web 26 drawn from roll 25 with a Web 33 drawn from roll 32.

A shaft 34 is carried at its ends by the opposite bars '7, said shaft being positioned beneath the heating head 10 carried by the opposite arms 9. A roll 35 is positioned upon the shaft 34 and comprises a tubular member 36 upon the outer surface of which a layer 37 of U resilient material is carried. The resilient material 37 is preferably constructed of Teflon but can be constructed of substantially any resilient material which can withstand the temperatures encountered in the sealing operation. The tubular member 36 is positioned upon the shaft 34 by means of ball bearing assemblies 38 whereby the roll 35 freely rotates upon the shaft 34.

The material comprising the band 26, as has been hereinbefore described, may comprise a fibrous web of sheet material which may be wax coated or, if desired, the coating may comprise any type of coating which can 'be rendered adhesive by the application of heat. Thus, in general, the function of the band sealing device is to apply heat to either the entire area of the band 26 to render it adhesive whereby it may be joined to the web 33 of wrapper material, or the heat may be applied to predetermined portions of the band 26 such as the opposite lateral edge portions thereof whereby the band may be adhesively united to the wrapper material 33 along said edge portions. In some instances it is desirable to adhesively unite the entire area of the band material to the wrapping material and in other instances it is desirable only to unite the lateral edge portions of the band material to the wrapper material. As one of the features of the present invention the band sealing device 2 can be employed to carry out either operation, as desired.

Where the entire area of the band 26 is to be united to the wrapper material 33, the web of band material 26 after passing over the guide roll 27 may be trained directly over the cylindrical surface of the heating shoe as shown best at 39 in FIG. 1. It will be noted that the heating shoe 10 has its entire cylindrical surface heated, that is, the shoe comprises a continuous block of metallic material which will be heated by the heating unit 11. Thus, when the band material 26 passes over the heating shoe, the coating carried by said band is softened and rendered adhesive. Thereafter the heated web 26 is trained around roll and passes between the nip of roll 35 and roll 32. It will be noted that the frame of the band sealing device, being swingable about shaft 5. permits roll 35 to assume a tangent position with respect to the roll of wrapper material 32 and a desired degree of pressure may be established between the roll 35 and the roll 32. In passing between rolls 35 and 32 the web 26 is brought into contact with the outermost layer of web material upon the roll 32 and becomes adhesively united thereto. The web 33 of wrapper material is thereafter stripped from the roll 32 and is carried as a composite web over a guide roll 41 whereby the composite web may be directed to a wrapping machine (not shown) such as a machine for wrapping loaves of bread. The wrapping machine furnishes the tension whereby the band 26 and wrapper 33 and composite web 40 are drawn forwardly through the device 2.

A strap of flexible material 42 is secured at one end to the transverse frame member 8 and its opposite end may carry a weight 43, the strap being draped over a portion of the roll 25. The weighted strap thus functions as a counterbalance for the frame of the band sealing device and also controls the withdrawal of the web 26 from the roll 25. By changing weights 43 the pressure of roll 35 upon roll 32 may be controlled.

A pair of spaced guide rods 44 are secured at their respective ends, as by screws 45, to the opposite frame bars 7. A pair of heating shoes 46, one right-hand and the other left-hand. are slidably mounted upon the guide rods 44. each shoe being provided with a pair of spaced apertures through which the rods extend. Each of the opposite frame bars 7 is provided with an upwardly opening slot or notch 47 in which an end-abutting pair of screws 48 and 49 are loosely positioned, said endabutting screws being rigidly connected together at their abutting ends by a coupling 50.

The threads upon screw 48 are the reverse of the threads upon screw 49 and an end portion of each screw extends outwardly from a respective frame bar 7. A threaded collar 51 engages with the threads of respective screws outwardly of each frame bar, and, as will be hereinafter more fully described, said collars prevent unintended axial movement of the screws 48 and 49. Each of the heating shoes 46 is provided with an internally threaded bore 52 whereby one of said shoes is threadedly engaged with each screw.

The extending end of screw 49 carries a knob 53 whereby both of said screws may be rotated. The arrangement is such that when the screws are rotated, the shoes 46 simultaneously move toward or away from each other depending upon the direction of rotation of the screws. The screws and the shoes carried thereby may also be moved as a unit by manipulating the collars 51, that is, by backing one or the other collar away from its abutting position with a bar 7; axially moving the screws in notches 47, and then threadedly moving the other collar into abutting position with the other frame bar 7. Thus, the shoes 46 may be set to a predetermined relationship with respect to each other by rotating screws 48 and 49 and the preset shoes may be moved laterally simultaneously in preset position by the appropriate manipulation of the collars and appropriate axial movement of the screws in the notches 47.

The shoes 46 are similar to each other except that one is right-hand and the other is left-hand. Each shoe is provided with a longitudinal slot 54, said slots, when the shoes are assembled in operative position, confronting each other. An electric heating element 55 is carried in a bore provided in each shoe, and suitable electrical conductors together with a conventional adjustable thermostatic control (not shown) connect said elements to a source of electricity. Thus, each of the shoes 46 is controllahly heated.

In utilizing this portion of the machine the band or web 26, trained over the guide roll 27, instead of being trained over the semicylindrical shoe 10 has its lateral edges threaded through the opposite slots 54 provided in the shoes 46. Prior to the threading operation the opposite shoes 46 are appropriately spaced from each other by the manipulation of the knob 53 to space the bases of the slots 54 from each other a distance slightly greater than the width of the band 26, as shown best in FIGS. 2 and 4. The band 26 after having its edge portions pass through the slots 54 is then trained directly around the pressure roll 35 and inasmuch as the coating upon the band 26 has been rendered adhesive adjacent the lateral edges thereof, said band is adhesively united to the wrapper web 33. However, in this case only the lateral edge portions of the band make adhesive contact with the wrapper material.

Referring particularly to FIGS. 9 and 10 two wrapped loaves of bread are diagrammatically shown. In FIG. 9 the wrapping material comprising the web 33 embraces the entire bread loaf. Said wrapper is indicated by the reference numeral 33a. The band is shown as being centrally located and is disposed around the girth of the bread and is adhesively united to the inner surface of the wrapper 33a. The band is indicated in FIG. 9 as 26a. It may be desired to offset the band relative to the longitudinal center of the bread. The band 26b in FIG. 10 is shown as being offset with respect to the bread loaf and with respect to the wrapper indicated at 33b. Of course, it may be desired to offset the band in the opposite direction from the center of the bread loaf. This may also be done by the machine 2.

When it is desired to centrally dispose the band relative to the bread loaf and also relative to the wrapper, as shown in FIG. 9, the shoes 46 may be positioned centrally between the frame bars 7, as shown best in full lines in FIG. 4. If it is desired to offset the band in one direction or the other direction relative to the longitudinal center of the bread loaf, the screws 48 and 49, and the shoes .46,Qmay be moved laterally to the right or to the left by the proper manipulation of the collars 51 which will perrnifaxial movement of the screws in the notches 47. For example, the screws and shoes may be moved as indicated by the dotted lines in FIG. 4. Of course, when the screws havebeen moved to their desired position, the collars 51 are threaded into abutting contact with the respective frame bars 7. Each of the collars 51 is providedwith a set screw 56 which may be manipulated by a winged head 57 whereby when the collars are in desired position they may be locked with respect to the frame bars 7 and thus [axial movement of the screws from the preset position would beprevented.

. Thus, the hereinbefore described arrangement comprising the screws 48 and 49 and the shoes 46, mounted as hereinbefore described,'permits operation upon bands of wide ranges of widths. Also, the positioning of the band with respect to the wrapper may also be varied by manipulating the mechanism as has been hereinbefore described.

In view of the fact that the band 26 carries a coating of thermoplastic material such as wax and that said material is heated during its passage through the slots 54, said material may be heated to a flowable state and it is possible that accumulations thereof may form adjacent the inner end portions of the screws 48 and 49. If such accumulations were permitted to set, for instance, when the machine is shut down, difiiculty may be encountered in manipulating the screws to move the shoes thereon. To obviate this contingency, accordion folded substantially cylindrical sleeves 58 maybe disposed in embracing relationship with respect to the inner portions of the screws, the ends of the sleeves 58 being secured to a shoe and to the coupling 50.. The arrangement is such that because of the extensible and contractible nature of the sleeves 58 the shoes 46 may move desired distances away from and toward the coupling 50. The nature of the sleeves 58 will be such that the largest and smallest width bands may be accommodated without having the band resting upon the upper surfaces of the sleeves.

To afford a convenient control of the heating shoes and 46, a switch plate 59 is mounted upon one of the plates 3 and a double-throw, center-off switch (not shown) may be carried by said switch plate, the switch being controlled by the toggle arm 60 which may be moved upwardly or downwardly selectively to energize shoe 10 or shoes 46 or may be moved to center position to deenergize both shoes. A pilot light 61 is also mounted upon the plate 59 to warn the operator that shoe 10 or shoes 46 are energized.

In view of the fact that the shoes 46, when in use, are relatively hot, sometimes being at a temperature in the neighborhood of about 400 F., guard strips 62 are carried upon the upper surfaces of the shoes 46, said strips being constructed of a low heat conductive material such as asbestos or the like. The strips 62 are secured to the shoes by screws 63 which pass through grommets or washers 64 which space the strips from the upper surfaces of the shoes. Thus, when it is desired to thread band 26 through the slots 54 in shoes 46 when the shoes are heated, the operators hands will be protected from, what may prove to be, serious burns.

Referring particularly to FIG. 5, a modification of the invention is shown. The modification resides in a different type of heating shoe which may be employed with a frame structure basically the same as the one hereinbefore described. The modified heating shoe, designated generally at 65 in FIG. 5, is positioned between arms 9', which correspond to arms 9, hereinbefore described.

The shoe 65 comprises essentially three members 66, 67 and 68, each of which has a sernicylindrical surface. The members 66, 67 and 68 are carried by a plate 69 supported, in turn, by a supporting plate 70 secured at its ends to the opposite arms 9'. The members 66, 67

l 6 andi68 are'secured to plate 69 through tubular spacers 72. Members 66 and 68 are provided with bores 73 and 74, respectively, in which electric heating elements 75 and 76 are positioned, said heating elements being connected by leads 77 through a conventional thermostat 78 positioned beneath mem-. ber, 66, the thermostat being connected to a source of electricity (not shown) by cable 79. The thermostat 78 is adjustable and can be adjusted to maintain the members 66 and '68 at a desired temperature by the manipulation of knob 80. 7

It will be noted that member 67 is unheated and is spaced from the heated members 66 and 68. According- 1y, when a band 26 corresponding to band 26, hereinbefore described, is trained-around the shoe 65, the edge portions of the band pass. over the heated members .66 and 68 and the central portion of the band passes over the unheated member 67. Thus, the edge portions of the band are rendered adhesive whereas the central por-' tion remains non-adhesive.

The arms 9' also carry a pressure roller 35' which is identicalwith pressure roller 35, and without further detailed description thereof, primed corresponding reference numerals will be applied to corresponding parts of the roller 35.

Of course, when the head 65 is employed it is unnecessary to employ the shoes 46 since in either case the edge portions of the band are heated to render the edge portions only adhesive. Referring particularly to FIGS. 6, 7 and 8, another modification of the invention is shown. Similar to the modification shown in FIG. 5, the essential difierence resides in the heating head assembly 81. The frame of the'band sealer shown in-FIGS. 6, 7 and 8 is the same as that shown and described in FIGS. 1 and 2 and without further detailed description corresponding similar parts will be designated by corresponding double-primed reference numerals.

. Theheater head or shoe assembly 81 comprises a pair of spaced parallel rods 82'which are secured at their opposite ends to opposite arms 9" by means of screws 83. A pair of heating shoes 84 are carried by said rods, each shoe being provided with a pair of bores through which the rods extend. The shoes 84 are movable along the length of the rods, and each shoe carries a set screw 85 whereby the shoes 84 may be locked at a desired position along said rods.

A plurality of guide blocks 86, each being provided with a pair of apertures through which the rods 82 extend, are slidably carried upon said rods, each block 86 carrying a set screw 87 for locking the blocks in desired position upon the rods. The blocks 86 are carried by the rods 82 between the spaced shoes 84.

The shoes 84 and guide blocks 86 are each provided with a cylindrical surface over which the band 29" may be trained in its passage from guide roll 27 to the nip between pressure roll 35 and roll 32".

Each of the shoes 84 is provided with an aperture for the reception of an electric heating unit 88 which, in turn, may be connected to a source of electricity (not shown). If desired, conventional adjustable thermostats (not shown) similar to thermostats 14 and 78 may be associated with one or both shoes 84 to control the temperature thereof.

Each of the shoes 84, at its forward portion extends downwardly adjacent the path of travel of the band 39" from the shoes to the pressure roll 35", and the lower portion of each shoe is closely spaced and follows the contour of the pressure roll, as shown best at 89 in FIG. 6. Thus, the portion of the band which passes over the cylindrical portions of shoes 84 and is heated thereby, retains its heat by its proximity of the downwardly extending portions of the shoes 84.

The arrangement is such that the assembly 81 may be adjusted to heat the edge portions of bands of different widths by the relative positioning of the shoes 84. In

by screws 1 which extend addition, both shoes may be moved together laterally in one direction or the other for purposes of centering or offsetting the band upon the wrapper.

.To support the central portion of theband'as it passes over the shoe assembly 81, the guide blocks 86 may be moved to, and locked at, desired spaced positions with respect to each other and with respect to the shoes 84.

It is apparent that herein is contemplated a bandsealing device which is extremely flexible in operation, is rugged and can be manufactured economically. Modifications of the present invention may occur to those skilled in the art which do not depart from the spirit of the invention and, hence, it is not'intended that the invention be limited to the exact details shown and described except as necessitated by the appended claims.

We claim as our invention:

1. A band sealing device which comprises, a support, a frame having spaced parallel frame members pivotally mounted upon said support, a pressure roll carried by saidframe members, a heating shoe assembly carried by said frame members intermediate said pivotal mounting and said pressure roll, shoe-supporting means'carried by said frame members and extending between said frame members at substantially right-angles thereto, a pair of spaced shoes slidably mounted upon said shoe-supporting means, screw means carried by said frame members and threadedly engaged with said shoes, the threads of said screw on each side of the transverse axis thereof being oppositely pitched, one of said shoes being engaged with each set of threads whereby rotation of said screw simultaneously moves said shoes in opposite directions to space said shoes predetermined variable distances from each other, means for heating said shoes, means for passing a band of web material carrying thermoplastic coating in lateral edge portion contact with said shoes to-heat the lateral edge portions of said band and render the coating on the heated edge portions in adhesivecondition, a roll of wrapper material disposed adjacent saidpressure roll toward which said pressure roll swingsabout saidpivotal mounting to form a nip, said band being passed through the nip of said pressure roll'and said roll of wrapper material after passage incontact with said'shoes adhesively to unite under pressure the adhesive edge portions of the band material to the outermost layer of the wrapper material on said wrapper material roll.

2. A device as contemplated in claim l'wherein said screw means is axially movable upon said frame to move said shoes together relative to said frame members, and means carried by said screw means for locking said screw means in a predetermined position relative to said frame members.

3. A heating device for heating opposite lateral edge portions of a passing band carrying a coating which can be rendered adhesive when heated, said device comprising a frame, a heating shoe assembly carried by said frame, said shoe assembly comprising guide means carried by said frame, a pair of heating'shoes slidably mounted on said guide means, screw means carried by said frame and threadedly engaged with each shoe whereby rotation of said screw means moves said shoes simultaneously in opposite directions, each of said shoes being provided with an elongated slot through which the edge portions of said passing band may be threaded, means for heating said shoes to render the passing edge portions of the band in adhesive condition whereby said edge portions of the band may be adhesively united to a sheet of wrapper material.

4. A device as contemplated by claim 3 wherein said screw means is axially movable relative to said frame to move both of said shoes together with said screw means, and means carried by said screw means for locking said screw means at a predetermined position relative to said frame.

References Cited in the file of this patent UNITED STATES PATENTS 1,142,801 Delaney June 15, 1915 2,082,114 Littlefield June 1, 1937 2,814,328 Jess NOV. 26, 1957

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