US3563003A - Wrapping machine - Google Patents

Abstract

A PACKAGE WRAPPING MACHINE HAVING ROLLS OF WRAPPING MATERIAL SUPPORTED ON A ROTATABLE SHAFT HELD AT EITHER END BY A FRAMEWORK. A PLATFORM FOR WRAPPING PACKAGES IS MOUNTED BEHIND A CLOSELY SPACED HEATED SEALING PLATE ON THE FRAMEWORK. AN ELECTRICALLY HEATED WIRE IS SUSPENDED BY TWO ROTATABLY MOUNTED BRACKETS AND POSITIONED BETWEEN THE WRAPPING PLATFORM AND THE SEALING PLATE. IN ITS RECESSED POSITION, THE HEATED WIRE IS AT A LOWER LEVEL THAN THE PLATFORM IN ORDER TO PREVENT INADVERTENT CONTACT WITH THE WIRE. DURING USE, THE HEATED WIRE IS RAISED TO A HIGHER LEVEL BY AN ACTUATOR WHICH ROTATES THE BRACKETS HOLDING IT. THE ACTUATOR MAY BE A PLATE WHICH IS MOTIVATED BY CONTACT WITH THE PACKAGE AS IT IS MOVED FROM THE WRAPPING PLATFORM TO THE HEATING PLATE. A MANUALLY OPERATED FOOT PEDAL MAY ALSO FUNCTION AS THE ACTUATOR. A SHIELD IS OPTIONAL TO FURTHER PROTECT THE HEATED WIRE IN ITS RECESSED POSITION.

Description

Feb. 16, 1971 PIZMOHT 3,563,003

WRAPPING MACHINE Filed Nov. 6, 1968 2 Sheets-Sheet l INVENTOR. FRANK PIZMOHT ATTORNEYS.

Feb. 16, 1971 F. P-IZMOHT 3,563,003

WRAPPING MACHINE Filed Nov. 6, 1968 2 Sheets-Sheet 2 F|G.5 E216 l4? l3? l5 l6 M '56 INVENTOR. FRANK Pl ZMOHT 4%, 142 M WW ATTORNEYS.

United States Patent 3,563,003 WRAPPING MACHINE Frank Pizmoht, Willoughby, Ohio, assignor to Cleveland Heat Sealing Equipment Manufacturing Company, Cleveland, Ohio, a corporation of Ohio Filed Nov. 6, 1968, Ser. No. 773,796 Int. Cl. B65b 67/10 US. Cl. 53-390 15 Claims ABSTRACT OF THE DISCLOSURE A package wrapping machine having rolls of wrapping material supported on a rotatable shaft held at either end by a framework. A platform for wrapping packages is mounted behind a closely spaced heated sealing plate on the framework. An electrically heated wire is suspended by two rotatably mounted brackets and positioned between the wrapping platform and the sealing plate. In its recessed position, the heated wire is at a lower level than the platform in order to prevent inadvertent contact with the wire. During use, the heated wire is raised to a higher level by an actuator which rotates the brackets holding it. The actuator may be a plate which is motivated by contact with the package as it is moved from the wrapping platform to the heating plate. A manually operated foot pedal may also function as the actuator. A shield is optional to further protect the heated wire in its recessed position.

BACKGROUND OF THE INVENTION Normally, a package wrapping machine has rolls of wrapping material suspended either above or below a platform. Slightly lower and closely spaced from the platform, on which the packages are wrapped, is a heated sealing plate. An electrically heated wire is positioned between the platform and the sealing plate at about the level of the platform.

The wrapping material, which is usually some type of temperature sensitive thermoplastic film, such as polyethylene and polyvinyl chloride, unrolls to a position near the platform where the package is wrapped. After the package is wrapped, it is transferred from the wrapping platform to the sealing plate. During the transfer, the plastic wrapping material is pressed against the hot wire and severed. The remaining material is then tucked under the package and pressed against the heated plate to seal it.

The temperature control knob and switch are usually located below the hot Wire or on the side of the wrapping platform.

Many problems and inconveniences have developed as a direct result of the conventional construction of package wrapping machines. While the heated wires proximity to the wrapping platform is very convenient, it is also a constant source of burns to the operator. The operator normally stands in front of the sealing plate and reaches across the heated wire when drawing film from the rolls and wrapping packages on the platform. In this position he necessarily has his arms extended over the wire. Inattention or fatigue may cause the operator to lower his arms onto the heated wire. Moreover, the step of transferring the package from the wrapping platform to the heated plate normally requires the operator to retract his 3,563,003 Patented Feb. 16, 1971 "ice hands slightly above the wire. Even the slightest misjudgment could result in a severe burn.

It is possible for the operator to use an exaggerated movement to avoid the wire during the wrapping process. The operator may also lean over and look around the package to determine that the wrapping material alone is in contact with the heated wire. However, at best such movements are inefficient, awkward and tiring.

The position of the exposed heated wire creates another problem. The Wrapped package often contacts the hot wire while it is being removed from the wrapping platform. A burn in the wrapping material on the package naturally destroys the possibility of a hermetic seal. As a consequence, the package must be rewrapped. Moreover, if the burn extends through the wrapping material to the package, or goods therein, everything will probably have to be discarded. This is particularly true in the case of foods which are primarily wrapped with this type of machine.

Striking the heated wire with the package has other detrimental effects. The heated wire, which is relatively thin, soon bends and eventually breaks under such impacts. A bent wire, of course, makes it more difficult to obtain a fast, clean cut of the wrapping material. Only the higher sections of the nonuniform wire will contact and sever the wrapping material.

The exposed heated wire also burns anything that is inadvertently laid on the package wrapping machine while it is not in use.

Additional opportunity for burning the operators hands occurs because the temperature control, switch and fuse are usually located under the wire between the closely spaced wrapping platform and sealing plate. It is, thus, necessary to reach through a narrow opening partially formed by the heated wire to make any adjustment.

At times the controls are located on the side of the wrapping platform. While this location virtually eliminates the possibility of burning the operators hands, it has its own problem. The controls are very vulnerable to inadvertent change by bumping from anybody or anything.

This invention has virtually eliminated all of the disadvantages discussed above by providing a retractable heated wire and placing the controls under a pivotably mounted wrapping platform. In its recessed position, the heated wire is located well below the forward edge of the wrapping platform. -In this position, there is no serious chance that the operator will inadvertently contact the Wire while he is either wrapping a package or transferring it to the sealing plate. During the transfer, the wrapped package cannot contact the recessed heated wire because it simply cannot fit into the small space in which the wire is located. Thus, burnt packages and bent wires are also eliminated.

Once the package and the operators hands are safely beyond the heated wire, the wire is then raised to a position where it naturally severs the wrapping material. There are numerous actuators for raising the heated wire. An actuating plate in the path of the package during its transfer to the sealing plate as well as a manual foot pedal may act as the actuator.

The controls, namely, the temperature adjustment for the plate, on-off switch and fuse are located under the wrapping platform. The front edge of the platform is hinged so that the rear edge may be easily raised by the operator from his working position. The controls are thus easily accessible at a position remote from the heated wire and the side of the platform where they can easily be bumped.

DESCRIPTION OF THE INVENTION This invention relates to a package wrapping machine having a framework with means attached thereto for rotatably supporting rolls of wrapping material. A platform on which the packages are wrapped is connected to the framework. Closely spaced from and slightly below the level of the platform is a heated sealing plate. An electrically heated wire is supported between the platform and the sealing plate. The heated wire is retractable so that it is substantially below the front edge of the wrapping platform. A means for retracting and raising the electrically heated wire permits the eflicient and timely cutting of the wrapping material. An optional shield may be used to protect the wire in its retracted position.

FIG. 1 is a perspective view of the package wrapping machine of this invention.

FIG. 2 is a cut away side plan view of the mounting means for the heated wire.

FIG. 3 is a sectional of the heated wire and supporting structure taken through 33 of FIG. 1.

FIG. 4 is the device of FIG. 3 in a different position.

FIG. 5 is a perspective view of an alternate embodiment of the wrapping machine.

FIG. 6 is a sectional taken through 66 of FIG. 5 and shows a detailed view of the supporting structure for the electrically heated wire.

FIG. 7 shows the device of FIG. 6 in a dilferent position.

As illustrated in FIGS. 1 through 4, the package wrapping machine 10 comprises a framework 12 with side plates 14 and 16 extending upwardly from a base section 1 8. The base section 18 includes a bottom surface (not shown) and upwardly turned sides 20 and 22 generally tapering toward the forward end 24.

Attached to upper edges 26 and 28 of side plates 14 and 16 are rotatably mounted shafts 30 and 32. The ends of the shafts 30 and 32 are journaled in blocks 34, 36, 38 and 40. Side braces 42 and 44 on the shafts 30 and 32 secure the rolls of wrapping material in position.

Below the shafts 30 and 32 is a mounted roll of wrap ping material 46. The wrapping material is fed under the wrapping platform 48 which is pivotably mounted along its front edge 50 by means of a pin 52. When the rear of the wrapping platform 48 is rotated upwardly, the temperature control knob 54, fuse 56 and on-off switch (not illustrated) are exposed for adjustment by the operator.

The temperature control mount 56 regulates the temperature of a heated sealing plate 58 which is locatedslightly forward of but at a lower level than the wrapping platform 48. The sealing plate 58 may be coated with Teflon and is generally rectangular in shape having sides 60, front 62 and a downwardly tapering top 63.

Between the sealing plate 58 and the wrapping platform 48, an electrically heated wire is held by two brackets 66 and 68 through disc-shaped insulators 76 at either side of the machine. Electric wires 78 conduct current through the wire 64 thus causing it to heat.

The brackets 66 and 68 are also connected to shafts 70 and 72. The shaft 70 is pivotably mounted in the sides of the framework at 74, thus allowing the brackets to rotate.

An actuating plate 80 is welded or otherwise attached to at least the shaft 70 and usually to the shaft 72 to provide a means for pivoting the entire bracketed assembly about the pivot means 74.

When in its normal rest position as shown in FIG. 3, the heated wire 64 is protected by a shield 82 which has an S-shaped cross section and is attached near the forward edge 50 of the wrapping platform 48. The shield acts as a protection against inadvertent contact with the hot wire by either the operators hand or the package. While the shield adds additional protection, it should be noted that it is not absolutely necessary since the wire in its rest position is actually substantially below the top forward edge 84 of the wrapping platform 48. It is only necessary that the heated wire '64 is well below the front edge 50 of the wrapping platform 48. In this way anything that would happen to rest across the opening defined by the wrapping platform 48 and sealing plate 58 would not contact the wire even if the shield 82 were not present.

As illustrated in FIG. 4, when the actuating plate is pressed downwardly, the bracket 68 rotates counterclockwise about the shaft 70. During this rotation the heated wire 64 rises from its protected position below the shield 82 to a level nearly equal to that of the wrapping platform 48. In this position it is readily available to sever the plasticized wrapping material which is normally used with the machine.

In operation, the embodiment shown in FIGS. 1 through 4 has the wrapping material 46 pulled through an appropriate opening under the wrapping platform 48 to a position immediately in front of the heated wire 64. After the package is wrapped on the platform 48, it is then pulled toward the operator and across the actuating plate 80. As the actuating plate 80 is pressed downwardly, the heated wire 6-4 rises and severs the Wrapping material. As the package is further pulled toward the operator and onto the heated sealing plate 58, the actuating plate 80 is released and the wire retracts behind the shield- 82. The wire retracts because the brackets holding it are counterbalanced to rotate about the shaft 70 to its lowest position. A spring or other mechanism may be used to recess the wire.

During the cutting motion, the package has its rearwardly facing edge directly above the hot wire so that there is no flap remaining after the cut is made. Thus, as the wrapped package comes to rest on the heated sealing plate 58, it can be immediately sealed in a compact package without any further movement by the operator.

As seen in FIGS. 5 through 7, a second embodiment of the wrapping machine has shafts 101, 102 and 104 rotatably in pairs of blocks 106. The blocks .106- are supported on a framework 108 which includes vertical supports 110, 112, 114 and 116 which are, in turn, mounted on wheels 118. Cross members 120, 122, 124, 126, 128, and 132 plus other members are not shown from the rest of the framework. Above the framework there is a wrapping platform 134 having sides 136 and a front 138. A film selector 140 is located under the wrapping platform and a selector handle [141. extends out from the side. The film selector 140 allows the operator to select film from any one of the shafts 100, :102 or 104 without rethreading the machine.

In front of the wrapping platform 134 and at a slightly lower level is the heating plate 142. The heating plate 142 has a top surface 144 generally tapering downwardly as a convenience for the operator. There are sides 146 and a front 148 to support the top surface 144. Between the wrapping platform 134 and the sealing plate 142 is an electrically heated wire 150. Insulators 152 and appropriate holding means 154 such as a screw or bolt secure the electrically heated wire to brackets 156. The brackets 156 are themselves held by a shaft 158 which is rotatably secured to the framework by a panel 159. A second shaft 160 is supported between the brackets 156 and engages a concave cradle 162 which is mounted at the upper end of a push rod 164. The push rod 164 extends downwardly from the cradle through apertures in the cross members 120, 122 and 124 of the framework. Stops 125 and 127 in the form of rings on the push rod limit its movement by engaging a cross member of the frame. The lower end of the push rod 164 is engaged by a projection 166 from a rotatably mounted shaft 168. The shaft 168 has its ends secured to downwardly extending blocks 170 and has a foot pedal 172 extending radially outwardly therefrom. The foot pedal has a V-shaped cross section so that a front section 173 is convenient for the operator.

In the embodiment shown in FIGS. through 7 the wrapping operation is identical. However, in this embodiment the heated wire is raised when the operator places his foot on the pedal 172, thus, rotating the shaft 168 and the bar 166. The bar engages the lower end of and raises the push rod .164 and cradle 162. The extent of the motion of the push rod is governed by stops 125 and 127. The cradle 162 generally has a concave shape and engages the shaft 160 which is rigidly attached to the bracket I156. The shaft 160 moves along the cradle 162, thus, raising the bracket and the heated wire 150 to a position where it is available to sever the wrapping material.

Other devices will be apparent to move the heated wire from its recessed position. For example, springbiased pins on the ends of the heated wire could fit in slots in the bracket to provide a reciprocal motion. It is also possible to have the heated wire move from behind a shield or to have a retractable shield and a stationary wire.

For ease of description, the principles of the invention have been set forth in connection with but two illustrated embodiments. It is not my intention that the illustrated embodiments nor the terminology employed in describing them be limiting inasmuch as variations in these may be made without departing from the spirit of the invention. Rather I desire to be restricted only by the scope of the appended claims.

I claim:

1. A package wrapping machine comprising:

a framework;

means attached to the framework for rotatably supporting a roll of wrapping material;

a platform connected to the framework on which said packages are wrapped;

a heated sealing plate mounted on the framework and substantially adjacent to the platform but spaced therefrom;

an electrically heated wire suspended between the platform and sealing plate;

means for moving the heated wire to a position where it is accessible to cut the wrapping material and re cessing the heated wire to a position where it cannot readily be contacted, said means for moving and re cessing including an actuating plate that is operatively connected to the heated wire and that is positioned near the space between the wrapping platform and the sealing plate so that the package may contact the actuating plate while it is being transferred to the sealing plate.

2. The package wrapping machine of claim 1 wherein the means for moving and recessing the electrically heated wire further includes pivotably mounted brackets which are operatively attached to the framework.

3. The package wrapping machine of claim 1 which further includes controls for the wrapping machine beneath the platform which is pivotably connected along one of its edges.

4. The package wrapping machine of claim 2 wherein said actuating plate is operatively connected to and extends radially outwardly from the brackets.

5. The package wrapping machine of claim 2 which further includes a shield which protects the heated wire in its recessed position.

6. A package wrapping machine comprising:

a framework;

means attached to the framework for rotatably sup porting a roll of wrapping material;

a platform connected to the framework on which said packages are wrapped;

a heated sealing plate mounted on the framework and substantially adjacent to the platform;

an electrically heated wire suspended between the platform and sealing plate;

means for moving the heated wire to a position where it is accessible to cut the wrapping material and recessing the heated wire to a position where it cannot readily be contacted;

the means for moving and recessing including pivotably mounted brackets which are operatively attached to the framework, a push rod with an upwardly facing concave cradle on its upper end which engages a rod attached to at least one of the brackets in order to pivot the brackets; and

means for actuating the push rod.

7. The package wrapping machine of claim 6 wherein the push rod is actuated by a pivotably mounted foot pedal.

8. The package wrapping machine of claim 7 wherein the foot pedal is attached to a pivotably mounted shaft operatively attached to the framework, said shaft having a radially extending member extending therefrom which abuts against and motivates the push rod when the foot pedal is depressed.

9. The package wrapping machine of claim 8 wherein the push rod extends through framework members along one side of said framework and is supported by said framework.

10. The package wrapping machine of claim 9 wherein means are mounted on said push rod for regulating the reciprocating movement thereof.

11. The package wrapping machine of claim 10 wherein said means for regulating the movement of the push rods includes radially extending projections on the push rod which engage members of the framework.

12. The package wrapping machine of claim 11 wherein the temperature controls for the electrically heated wire are located beneath the platform which is pivotably mounted.

13. A package wrapping machine comprising:

a framework;

shafts supported on the framework for rotatably supporting rolls of thermoplastic wrapping material;

a platform connected to the framework on which the packages are wrapped;

a heated sealing plate mounted on the framework adjacent to and in front of the platform;

an electrically heated wire suspended between the platform and sealing plate;

brackets supporting the heated wire;

a shield mounted between the platform and the sealing plate to protect the heated wire;

means for moving the heated wire relative to the shield to expose and recess the heated wire, including an actuating plate operatively connected to the heated wire to permit the movement thereof so that movement of a package to the sealing plate from the wrapping platform engages the actuating plate and moves the heated wire to a position where it is accessible to cut the wrapping material.

14. The package wrapping machine of claim 13 wherein the heated wire is held by pivotably mounted brackets, the platform is pivoted at one end and controls are located beneath the platform.

15. A package wrapping machine comprising:

a framework;

a first shaft attached to the framework for rotatably supporting thermoplastic material;

a platform connected to the framework above the shaft for wrapping packages;

a heated sealing plate mounted on the framework and substantially adjacent to the platform;

an electrically heated wire suspended between two brackets between the wrapping platform and the sealing plate;

a second shaft connected to the framework and rotatably supporting the brackets;

8 a third shaft suspended between the two brackets; References Cited a push rod extending through the horizontal portions UNITED STATES PATENTS of the framework and having a generally concave cradle at one end; 2,842,910 7/1958 Reed 53 39()X the cradle so positioned to engage the th haft; 5 3,043,071 7/ 1 62 Sadell 53 390 a foot pedal operatively connected to the push rod so 3298265 1/,1967 Mlnlcan et that depression of the foot pedal causes the Cradle 3,348,356 1 /1967 Curtis 53 3 on the push rod to engage the third shaft, rotate the brackets and raise the heated wire. TRAVIS MCGEHEE Pnmary Exammer

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