BACKGROUND OF THE INVENTION Glass fiber insulation products are typically packaged either as flat or folded batts in bags, or as rolls of long insulation blankets. Typically, two, three, or more strips of building insulation are formed in side-by-side relationship and discharged longitudinally off the end of the production line. Each of the strips or blankets comprises a layer of compressible fibers, optionally held together by a binder and, in some instances, adhered to a facing. The insulating strip is commonly either about 15 or 23 inches (38.10 or 58.42 centimeters) wide, with the thickness of the fibrous insulating layer being at least about 3.5 inches. A lengthy roll of such a strip, capable of covering up to 75 square feet (6.97 square meter), for example, can be quite bulky if not compressed substantially during packaging. In fact, the compression during packaging should be limited only by the degree to which the fibers can return or recover substantially to the desired thickness of the layer after the package roll is opened.

Glass fiber insulation packaging machines for rolling glass fiber insulation products into rolls are of two general types. The first employs a mandrel to which the leading edge of the insulation blanket is attached for rolling up. These machines are somewhat deficient in that they typically overcompress the leading portion of the blanket, resulting in loss of recovery and insulation value. The other machine for insulation rolls is the belt roll-up machine, which uses a main endless belt which forms a loop in itself located in the path of the compressible strip of insulation material being lineally moved toward the belt from the production line.

The belt roll-up machine can receive a compressible strip of insulation directly from the end of a production line. As the compressible strip is moved into the loop, the belt is moved in a manner such that the strip is rolled on itself with the facing sheet of the

insulation strip, if any, facing outwardly. The belt is maintained under tension as the roll is wound so that increasing pressure is maintained on the roll as the loop enlarges to accommodate the ever increasing diameter of the roll being packaged. The compressible strip is cut to a predetermined length on the production line and, as the trailing end of the strip is moved toward the loop, adhesive tape is applied thereto. A forward portion of the tape is adhered to the trailing end of the strip, and a rearward portion of the tape extending rearwardly thereof is adhered to the previous wrap of the strip. The roll is completely packaged by the time the strip moves into the loop and turns approximately one more revolution to cause the tape to adhere to the previous wrap. At this time, a sub-frame supporting and positioning the lower loop portion of the main belt is swung away from the main frame to straighten the portion of the belt forming the loop, thereby causing the packaged roll to be discharged downwardly.

While the use of adhesive tape has been somewhat successful, it has several disadvantages. First, the paper adhesive tape may be applied unevenly to the packaged roll. When the paper tape is pulled off, large amounts of the insulation material may be pulled off along with the paper tape, thereby damaging the roll product. For a rolled fiber glass insulation product, the insulation product may be later required to pass fire testing.

If too much of the insulation material is pulled off by the paper tape, then the insulation product may no longer pass the fire testing, rendering the insulation product useless for the purchaser. Second, the use of adhesive tape increases the cost of the roll product. The cost of the material required to wrap a roll is significantly less than the current adhesive paper tape. In addition, the adhesive tape has an approximate runtime of forty-five minutes before the supply of adhesive paper tape needs to be refilled by the operator.

This comparatively short amount of runtime reduces production time. This decrease in production time results in an undesirable increase of the cost of the roll product. Third, the paper tape needs to be substantially aligned when applied in-line with the product.

Any misalignment of the paper tape allows the rolled product to become undone or bulge unevenly. In addition, the adhesive may stick to surrounding material, rather than to the roll product. Finally, the adhesive paper tape is not recyclable which increases the cost of waste disposal for both the manufacturer and the customer. Thus, it is desirable to wrap a roll product more efficiently and effectively while minimizing any waste or damage to the roll product.

SUMMARY OF THE INVENTION The above objects as well as other objects not specifically enumerated are achieved by a wrapping insulation material, the method comprising the steps of : feeding a strip of insulation material to be wrapped along a conveyor line, the strip of insulation material having a trailing end; paying out a sheet of packaging material, a portion of the packaging material overlapping the trailing end of the strip of insulation material; rolling the strip of insulation material and the packaging material such that the packaging material overlaps a portion of itself and forms an outer surface of the rolled strip of insulation material, whereby a radial expansion of the rolled strip of insulation material produces a tension on the packaging material, thereby causing the packaging material to hold the rolled strip of insulation in place.

In another embodiment of the invention, the method includes the steps of : feeding a strip of insulation material to be wrapped along a conveyor line, the strip of insulation material having a trailing end; paying out a sheet of packaging material behind the trailing end of the strip of insulation material; rolling the strip of insulation material and the packaging material such that the packaging material overlaps a portion of itself and forms an outer surface of the rolled strip of insulation material, whereby a radial expansion of the rolled strip of insulation material produces a tension on the packaging material, thereby causing the packaging material to hold the rolled strip of insulation in place.

In another embodiment, there is provided an insulation package comprising a roll of strip of insulation material surrounded by a sheet of packaging material that forms an outer surface of the roll of insulation material. The sheet of packaging material is longer than the circumference of the roll of insulation material so that a portion of the sheet of the packaging material overlaps on itself. The insulation material is held in compression by the sheet of packaging material, and the expansive force of the compressed insulation material produces a tension on the packaging material, wherein the coefficient of static friction of the sheet of packaging material is sufficient to prevent the overlapped sheet of packaging material from slipping on itself. The sheet of packaging material maintains the roll of insulation material in compression.

Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic side view in elevation, with parts broken away, of packaging apparatus embodying the invention; Figs. 2-5 are enlarged, schematic side views in elevation of a portion of the packaging apparatus showing various components in different positions during the packaging and discharging of a strip of compressible material; Fig. 6 is a further enlarged, schematic side view in elevation of certain components of the packaging machine according to the invention; Fig. 7 is a fragmentary plan view of supporting belts and a drive arrangement shown in Fig. 6; Fig. 8 is a transverse sectional view taken along the line of 8-8 of Fig. 7; Fig. 9 is a side elevational view of the packaging material dispenser according to the preferred embodiment of the invention; Fig. 10 is a side elevational view of an alternative embodiment of the packaging material dispenser of the invention; and Fig. 11 is a top plan view of the packaging material dispenser of Fig. 10.

DETAILED DESCRIPTION AND PREFERRED EMBODIMENTS OF THE INVENTION Referring now to the drawings, there is illustrated in Figs. 1-8, a packaging apparatus, shown generally at 20, for a roll product according to a preferred embodiment of the invention. A strip of insulation, specifically an insulating layer of glass fibers, with or without a facing sheet, is fed longitudinally to the packaging apparatus 20 from a production line, being cut to a predetermined length on the production line. It is to be understood that the invention can be used with other fibrous insulation materials, such as mineral wool and fibrous polymer insulation. The insulation is fed from the production line to a supply conveyor 22 and then moved up an inclined conveyor 24 toward a main endless belt 26 carried by a main frame 28. The belt 26 has a loop or pocket 30 formed therein which is in alignment with the inclined conveyor 24 to receive the forward end of the compressible strip of insulation.

Referring to Figs. 2 through 5, a strip 32 of insulation is shown moving up the conveyor 24 and directed by a guide plate 34 toward the throat or opening of loop 30.

From the loop, the main belt 26 extends around a throat roll 36 to a take-up or tension

mechanism, indicated generally at 38. This enables the loop 30 to expand as the insulation rolls up and yet maintains tension on the belt in order to maintain a compressive force or pressure on insulation 32 as each wrap is rolled. The take-up mechanism 38 includes lower, stationary idler rolls 40, and upper, vertically-movable, take-up rolls 42. The rolls 42 are urged upwardly to place the belt in tension but move downwardly as the size of the loop 30 increases. The rolls 32 are supported by chains 44 which are wound on sprockets 46. The chains 44 extend around the sprockets 46 sufficiently to enable the take-up rolls 42 to move between their extreme upper and lower positions, as shown in Figs. 2 and 4. The sprockets 46 are urged in a clockwise direction, as shown in Fig. 2, by spur gears, cams and a pressure cylinder 48. This mechanism is shown and discussed more fully in U. S. Pat. No. 3,964,235.

Beyond the take-up mechanism 38, the belt continues around idler rolls 50 and 52 and around a lower idler roll 54 carried by the pivotal sub-frame 56. The belt then extends below a slack control roll 58 which is rotatably carried by a lever 60 pivotally mounted on part of sub-frame 56. The lever is pivotally moved by a pneumatic ram 62 (Fig. 6) which is also pivotally mounted on a portion of the sub-frame 56, the roll 58 controlling the slack in the main belt 26 when the frame 56 is opened. The main belt 26 then extends around the tail roll 64 before returning to the loop portion 30.

The tail roll 64 is part of supporting conveyor 66 which also has head or drive roll 68 and intermediate idler rolls 70 and 72. These are rotatably carried by a lower portion of pivotal sub-frame 56. The conveyor 66 also includes a plurality of narrow belts 74 arranged in spaced, side-by-side relationship and extending around tail roll 64 and drive roll 68. In a preferred form, the belts 74 are timing belts with teeth 76 on the inner surfaces thereof. The drive roll 68 consists of a plurality of timing belt pulleys 78 having transverse recesses 80 which receive the teeth 76. The timing belt pulleys 78 also have edge shoulders 82 which maintain the belts 74 in a spaced apart relationship. The tail roll 64 has a smooth cylindrical surface with collars (not shown) which, along with the shoulders 82, maintain the belts 74 in a spaced apart relationship.

The conveyor 66 and the upper runs of belts 74 are located at an angle of about forty degrees to about fifty degrees with respect to the horizontal. This places the loop 30 at an appropriate angle and enables the leading edge of the insulation 32 to turn back on itself more readily to form the first wrap or core of the package.

The drive roll 68 and specifically timing belt pulleys 78 are mounted on and affixed to the drive shaft 84 having a double sprocket 86 thereon. This is connected by chains 88 (Fig. 6) to a sprocket 90 located on a jack shaft 92 and rotated through a drive sprocket 94, a chain 96, and a main drive sprocket 98 (Fig. 1) by a suitable motor on frame 28. Take-up roll 100 (FIG. 6) is located below the return run of belts 74 and is mounted on lever 102 connected to ram 104 which urges roll 100 against belts 74.

Pinch roll 106 (Figs. 2 and 5) urges main belt 26 toward the tail roll 64 and belts 74 cause the main belt 26 to be driven along with the timing belts 74 when the pinch roll 106 engages the belt 26. The pinch roll 106 is rotatably mounted on pivoted L-shaped levers 108 which are operated through a pneumatic ram 110.

When the package is complete, pivotal sub-frame 56 is opened, as shown in Fig. 5, to straighten the loop 30 and to discharge the package downwardly. For this purpose, a pneumatic ram 112 is connected to a portion of sub-frame 56 and to an upper corner portion of the main frame 28. At this time, the pinch roll 106 is also moved outwardly by the ram 110 to stop the movement of the main belt 26. After discharge, the pinch roll 106 again is moved into engagement with the belt 26 to cause the belt to immediately begin to be moved by the tail roll 64 and to form a loop 30 again. The apparatus 20 shown in Figs.

2-8 is discussed more fully in U. S. Pat. No. 4,114,530.

To maintain the roll of the compressible strip 32 in compression, one or more strips or sheets of packaging material, such as a polymer film, are either applied onto the conveyor belt 22 after the insulation strip 32 has passed, or onto the trailing end of the insulation strip 32 as it proceeds into the loop 30. If the sheet of packaging material is applied on top of the trailing end of the strip of insulation material, then when the package is completed, the leading edge of the sheet will be positioned beneath the trailing end of the insulation material and within the roll of insulation material. If the sheet of packaging material is applied after the trailing end of the strip of insulation material has passed, then when the package is completed, the leading edge of the sheet will be positioned on the outside of the roll of insulation material.

In the preferred embodiment, the polymer film has a thickness of approximately 1.2 mils and a width of approximately 15 inches (38.10 centimeters), and is commercially available as film product No. S5295 from Uline of Waukegan, Ill. Preferably, the polymer film is a stretch wrap polymer film. Also, preferably, the packaging material has a sufficiently high cohesive force that it clings to itself. Also, it is preferred that the

polymer film have a coefficient of static friction greater than about 0.5, and more preferably greater than about 1.0. Without being limited to a specific mechanism or theory, the mechanism for maintaining the packaging material in place around the roll of the insulation material is believed to be affected by the coefficient of static friction, by the cohesive forces of the packaging material, and possibly also by electrostatic forces.

To dispense the packaging material, one or more banks of dispensers, shown generally at 114 (Fig. 1), are located above the conveyor 22. The dispensers supply the packaging material to the conveyor 22, and, hence, to conveyor 24 below the insulation.

The plurality of banks enables refilling and servicing while maintaining some in use. It will also be appreciated that the invention can be practiced with one bank having a plurality of dispensers 114. The packaging material may be applied either in one or more narrow bands, or a full width roll wrap which covers the entire width of the insulation strip 32. Preferably, the inclined conveyor 24 has vacuum chambers 120 communicating with an upper run of a perforated belt thereon. The vacuum effectively holds the packaging material down and prevents it from being deflected by air currents. The vacuum also enables conveyor 24 to grip the insulation strip 32.

Referring now to Fig. 9, each dispenser 114 may include a supply, such as roll 124 of packaging material, shown as film web 126, preferably having a width of about fifteen inches. Alternatively, the film web 126 may comprise one or more narrow bands having a total width less than the width of the insulation strip 32. Preferably, the film web 126 is comprised of a polyethylene polymer based material, and the like. It should be realized that the invention can be practiced with any wrapping material as long as the wrapping material has a sufficient coefficient of friction on its surface to hold the finished package 122 in place. The dispenser 114 may use a pneumatic or other type of film roll brake (not shown) to prevent over-rotation of the film roll 124 during high speed material feeding. A film guide bar 128 may be used to provide the proper tension and feed angle when feeding the film web 126 from either the top or bottom of the roll 124, as indicated by the dashed lines in Fig. 9. The film web 126 may be driven by a drive means, such as a motor (not shown), to dispense the film web 126 at a rate up to about 400 feet/minute, depending on the speed of the conveyor 22.

The film web 126 is fed through a set of infeed pinch rollers 130 that may be driven by one or more infeed belts (not shown) in a well-known manner. A high speed cutter 132, such as a serrated knife, is located downstream of the infeed rollers 130 to

provide an accurate, perforated film cut when the proper length of the film web 126 has been dispensed. A final set of film outfeed rollers 134 tears the film web 126 at the perforation and drives the tail end of the film web 126 out of the dispenser 114, dropping it onto the conveyor 22. Therefore, it can be seen that the sheet of packaging material is separated as an individual sheet from the supply of packaging material, that is, roll 124, prior to introducing the packaging material to the strip of insulation material. Since the sheet of packaging material is separated from the roll 124, various air curtain and suction devices, not shown, may be necessary to keep the sheet of packaging material from flying away, as described above.

Similar to the infeed rollers 130, the outfeed rollers 134 may be driven by one or more outfeed belts (not shown) in a well-known manner. To dispense the proper length of film web 126, the infeed and outfeed pinch rollers 130,134 engage (as indicated by the dashed lines) to drive the film web 126 through the dispenser 114. Once the proper length of the film web 126 has been dispensed, the infeed and outfeed pinch rollers 130,134 are no longer driven to stop the movement of the film web 126 through the dispenser 114.

Then, the cutter 132 perforates the film web 126. Next, the outfeed rollers 134 rotate while the infeed rollers 130 remain stationary to tear the perforated film web 126 and drive the tail end of the film web 126 out of the dispenser 114 and onto the conveyor 22.

Referring now to Figs. 10 and 11, an alternate film dispenser design may also use a pneumatic or other type of film roll brake 136 to prevent over-rotation of the film roll 124 during high speed material feeding. The roll 124 may be driven by a drive means, such as the motor 138, to dispense the film web 126 at a rate up to about 400 feet/minute (2.03 meter/second), depending on the speed of the conveyor 22. The film web 126 is fed through or around at least one gravity dancer roller 140 and through a pair of film feed pinch rollers 142. A high speed film cutter 144 is located downstream of the pinch roller 142 to dispense a proper length of the film web 126 and drop the tail end of the film web 126 onto the conveyor 22.

In the operation of the packaging apparatus 20, the insulation is carried up conveyor 24 and into the loop 30, as shown in Figs. 3 and 4. As the loop 30 enlarges, the take-up rolls move downwardly. As the insulation strip 32 moves along the conveyors, a timing or sensing device (not shown) located upstream of the film dispensers 114, causes the film web dispensers 114 to pay out the film web 126 such that a portion of the film web 126, preferably about one-tenth to about one-quarter of the total length of the film

web 126 to be payed out, overlaps the trailing edge of the strip 32. For example, for film web 126 having a length of about eight to ten feet, about one to two feet of the film web 126 will overlap the trailing edge of the strip 32. Alternatively, the film web 126 may be payed out behind the insulation strip 32 and trail the insulation strip 32 as it travels on the conveyor 22. After the trailing edge of the strip 32 moves into the loop 30, the trailing edge rotates at least another revolution to cause the remainder (non-overlapping portion) of the film web 126 to overlap itself and form an outer surface of the finished package 122 (Fig. 5). The tendency of the rolled insulation strip 32 to expand radially outward causes tension to be placed on the now overlapped film web 126 which holds the finished package 122 in place. At this time, the piston 112 is actuated to move the sub-frame 56 in a counterclockwise direction and straighten the loop 30 to cause the finished package 122 (Fig. 5) to be ejected.

One important aspect of the invention is that there is no need to purposely stretch the film web 126 in order for it to hold the finished package 122 in place, in contrast to conventional stretch wrapping methods. Rather, the tendency of the rolled insulation strip 32 to expand radially outward produces a tension on the film web 126 forming the outer surface of the finished product 122. The resulting tension on the film web 126 combined with the coefficient of friction of the surface of the film web 126 holds the finished package 122 in place without the need for purposely stretching the film web or using adhesives as in conventional packaging methods. Unlike conventional packaging methods, the pre-measured and pre-cut film web 126 is detached from the film roll 122 and released before it proceeds up into the loop 30.

The problems associated with the use of conventional paper adhesive tape are alleviated by the use of the film web or packaging material 126 of the invention.

Specifically, the tendency of the rolled insulation strip 32 to expand radially outward causes tension to be placed on the overlapped film web 126 which holds the finished product 122 in place, without the need of a sealing means, such as heat, glue, and the like.

Once wrapped with the packaging material, the finished package 122 of the invention can easily be unrolled without damaging the insulation. By contrast, the adhesive properties of the paper tape increase the likelihood of damaging the insulation when the paper tape is removed from the finished package.

In addition, the sheet of packaging material 126 does not need to be flat or substantially aligned with the insulation strip 32, unlike paper adhesive tapes. Further, the

packaging material can also be payed out in a width approximately equal to the width of the insulation strip 32, or alternatively, the packaging material can also be payed out in one or more bands having a total width less than or equal to the total width of the insulation strip 32. This increased flexibility using the packaging material reduces the amount of material used to wrap the finished package 122, thereby reducing the cost associated with forming the finished package 122. Another advantage of using the packaging material is increased runtime, allowing a runtime of approximately four to eight hours, as compared to only about forty-five minutes of runtime for adhesive tape, thereby minimizing downtime of the production line. Finally, the packaging material is less expensive and more environmentally friendly than paper adhesive tape.

In accordance with the provisions of the patent statutes, the principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.