Method and apparatus for securing a final tail of film to a load
A method and apparatus for securing a final tail of film to a wrapped load are provided. The method includes dispensing a film web from a dispenser and providing relative rotation between the load and the dispenser to wrap the film web around the load. A blower is actuated and applies a stream of air to the film web as the film web extends along a film path between a corner of the load and the dispenser. While applying the stream of air to the film web, the film web is weakened between the corner of the load and the dispenser and then severed, and the final tail of film is secured to the load with the stream of air.
This application claims priority under 35 U.S.C. § 119 based on U.S. Provisional Application No. 60/733,766, filed Nov. 7, 2005, the complete disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTIONThe present invention relates to a method and apparatus for wrapping a load with packaging material. More particularly, the present invention relates to a method and apparatus that secures a final film tail, created as the packaging material between the wrapped load and the dispenser is severed, to the wrapped load.
BACKGROUND OF THE INVENTIONLoads have been stretch wrapped with stretch wrap packaging material by securing a leading end of the packaging material to the load or a clamp near a side of the load, dispensing the packaging material by providing relative rotation between the load and a packaging material dispenser to cause the load to be enveloped by the packaging material, and severing the packaging material between the load and a packaging material dispenser. The relative rotation between the load and the dispenser can be provided either by rotating the load on a turntable, or by translating the dispenser around a stationary load. Stretch wrapping usually employs a web of stretch film as the packaging material, and the machinery can be either automatic or semi-automatic.
At the end of the wrap cycle, a “tail” of film must be secured to the previously wrapped layers on the load. The tail can be the result of the trailing end of the film that is severed between the load and the dispenser at the end of the wrap cycle. Additionally, tails may result from the initial or leading end of the film that was formed into at least a partial rope and held outside the film wrap by a film clamp until released at the end of the wrap cycle. After the sides of the load are covered, the web of film is cut and the tail is usually “wiped” to press it against the load. If the tail is not secured, it may snag on forklift truck wheels, or be caught under adjacent loads during storage or transport, which may strip the wrapping material from the load. In addition, a long tail extending from the load can actuate photocells or motion sensors. A long tail extending from the load is also unsightly.
Most stretch wrapping depends on the tackiness of the film to secure the trailing end or “tail” of film to the previously wrapped layers on the load at the end of the wrapping cycle. The tackiness of the film can vary with the film's manufacturing variables, ambient temperature, humidity, dust, and the amount that the film has been stretched during the wrapping process. Methods used to attach the tail to the wrapped load include heat sealers, wipedown mechanisms, and “tucking” devices. The use of heat sealers has been problematic due to the unique environment required to seal film over varied surfaces, often without backing behind the film, and for many different types of packaging. Wipedown mechanisms include brushes or plastic/rubber loops that are “wiped” over the tail of the film to press it against the wrapped load. These devices include moving mechanical parts and must be positioned in close proximity to the load in order to contact the film tail and the load during the wipe down process. Several tucking devices have been developed but are not used due to their lack of robustness or high equipment costs. Most tucking devices involve holding an inner layer of wrap away from the load while a rope of film is inserted behind the inner wrap.
SUMMARY OF THE INVENTIONThe present invention is directed to an apparatus and a method for securing a final tail of film against a wrapped load, thereby potentially providing advantages and obviating a number of problems in prior art devices and methods.
According to one aspect of the present invention, a method of securing a final tail of film to a load while wrapping the load with a film web is provided. The method includes positioning the load on a load support surface. The method also includes dispensing a film web from a dispenser, and providing relative rotation between the load and the dispenser to wrap the film web around the load. The method further includes applying a stream of air to engage the film web as the film web extends along a film path between a corner of the load and the dispenser. The method further includes severing the film web between the corner of the load and the dispenser to produce the final tail of film, and securing the final tail of film to the load with the stream of air.
According to another aspect of the invention, a method of securing a final tail of film to a load while wrapping the load with a film web includes positioning the load on a load support surface, dispensing the film web from a dispenser, and providing relative rotation between the load and the dispenser to wrap the film web around the load.
The method also includes applying a stream of air to engage the film web as it extends along a film path between a corner of the load and the dispenser, and while applying the stream of air to the film web, severing the film web to produce the final tail of film. The method further includes securing the final tail of film to the load with the stream of air.
According to a further aspect of the invention, a method of securing a final tail of film to a load while wrapping the load with a film web includes positioning a load on a load support surface adjacent to a fixed wrapping structure, dispensing the film web from a dispenser, and providing relative rotation between the load and the dispenser to wrap the film web around the load and the fixed wrapping structure. The method also includes applying a stream of air to the film web as it extends along a film path between a corner of the load and the dispenser, and severing the film web between the corner of the load and the dispenser to produce the final tail of film. The method further includes securing the final tail of film to the overwrapped fixed wrapping structure with the stream of air.
According to one aspect of the present invention, an apparatus for securing a final tail of film to a load while wrapping the load with a film web is provided. The apparatus includes a film dispenser for dispensing the film web, means for providing relative rotation between the load and the dispenser to wrap the film web around the load, and a blower configured to apply a broad stream of air to engage the film web as the film web extends along a film path between a corner of the load and the dispenser. The apparatus also includes a controller configured to actuate the blower prior to the apparatus entering a last revolution of a wrapping cycle, and means for severing the film web, subsequent to actuation of the blower, to form the final tail of film. The blower is configured to apply the stream of air to the final tail of film to secure the final tail of film to the load.
According to a further aspect of the invention, an apparatus for securing an initial tail of film and a final tail of film to a load while wrapping the load with a film web includes a clamp for holding a leading end of a film web. The apparatus also includes means for providing relative rotation between the load and a dispenser to dispense the film web, a sweep plate positioned near the clamp for receiving a released leading end of the film web, and means for securing the released leading end of the film web to the load. The apparatus further includes a blower configured to apply a broad stream of air to engage the film web as it extends along a film path between a corner of the load and the dispenser, and a controller for actuating the blower prior to the apparatus entering a last revolution of a wrapping cycle. The apparatus further includes a cutting element for forming the final tail of film. The blower is configured to apply the stream of air to the final tail of film to secure the final tail of film to the load.
According to yet another aspect of the invention, a method of securing an initial tail of film and a final tail of film to a load while wrapping the load with a film web includes positioning a load on a load support surface, holding a leading end of a film web extending from a dispenser, and providing relative rotation between the load and the dispenser to wrap the film web around the load. The method further includes releasing the leading end of the film web, and securing the released leading end of the film web to the load. The method further includes applying a stream of air to engage the film web as it extends along a film path between a corner of the load and the dispenser, severing the film web to produce the final tail of film, and securing the final tail of film to previously dispensed layers of film with the stream of air.
According to another aspect of the invention, a method of wrapping a load includes positioning a load on a load support surface, dispensing a film web from a dispenser, and providing relative rotation between the load and the dispenser to wrap the film web around the load. The method also includes directing a stream of air at a corner of a load, wherein the film web extends between the corner of the load and the dispenser. The stream of air impacts the corner of the load in a manner such that at least a portion of the stream of air engages the film web to push the film web toward the load. The method further includes severing the film web between the corner of the load and the dispenser to produce a final tail of film, and continuing to direct at least a portion of the stream of air onto the film web until at least a portion of the final tail of film is substantially secured to the load.
According to a further aspect of the invention, the method of wrapping a load includes positioning a load to be wrapped, dispensing a film web from a dispenser, and providing relative rotation between the load and the dispenser to wrap the film web around the load. The method also includes, as a final revolution of the wrapping cycle beings, applying a stream of air to the film web as the film web extends between the corner of the load and the dispenser such that at least a portion of the stream of air engages the film web to push the film web toward the load. The method further includes, continuing to apply the stream of air to the film web while severing the film web to produce a final tail of film.
Additional objects and advantages of the invention will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and together with the description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made in detail to the present embodiment of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
As used herein, an “initial tail” of film results when a leading end of packaging material held during an initial stage of a wrapping cycle is released during the wrapping cycle. This released leading end generally has not been attached to a load, and instead, extends or trails from the load. As used herein, a “final tail” of film results when the packaging material extending between a corner of the load and a packaging material dispenser is severed at the end of the wrapping cycle. The portion of the film extending between the load and the severed end of film forms the final tail of film, and may be referred to as the “final tail of film,” the “trailing end of film,” or the “severed end of film.”
The present invention provides a method and apparatus for securing the final tail of film, which may result from severing the film between a corner of the load and the film dispenser, to the wrapped load. Accordingly, the present invention provides a means for securing the final tail of film to the wrapped load as the film web is severed between the load and the dispenser. The means for securing includes a blower or other air supply source that applies a broad stream of air to the film web to blow the film web against the wrapped load. The stream of air may be heated or unheated. The blower preferably is actuated during the last rotation of the wrapping cycle and before the film web is severed, in order to allow the stream of air to engage the film web while the film web is tensioned between the film dispenser and the load and during the film severing process. Because the film web is under tension during actuation of the blower, the film web is substantially flat as it is pressed or pushed by the stream of air against the previous layers of film on the wrapped load, providing maximum contact between the final film tail and the wrapped load. In addition, by applying the stream of air while the film web is being severed, the amount that the final tail of film “springs back” or curls up on itself after being separated from the film web is also minimized. The final tail of film is secured to the load during the wrap cycle, thus eliminating the need for additional steps which would increase wrap cycle time.
The present invention also provides an apparatus and method for securing an initial tail of film which may result from releasing the leading end of film during a wrapping cycle. Accordingly, the present invention provides a means for securing the leading end of film to the load after it is released. Preferably, the means for securing includes a substantially horizontal plate for receiving and supporting the leading end after it is released from the packaging material holder or clamp. The structure to which the released leading end may be affixed preferably is a substantially vertical fixed structure, such as a vertical plate.
As shown in
In an exemplary embodiment, stretch wrap packaging material is used. In the stretch wrapping art, stretch wrap packaging material is known to have a high yield coefficient, allowing the material to stretch a large amount during wrapping. Various other packaging materials, generally not considered to be stretch wrap materials, such as netting, strapping, banding, and tape, can also be used. As used herein, the terms “film,” “film web,” “stretch wrap,” “wrap,” and “packaging material” are interchangeable.
Dispenser 102 may also include a variety of rollers, optionally including prestretch rollers for stretching packaging material 116 longitudinally and/or transversely, to position, dispense, and stretch packaging material 116 as packaging material 116 is dispensed from packaging material roll 108.
According to one aspect of the present invention, apparatus 100 for wrapping load 124 includes means for providing relative rotation between dispenser 102 and load 124 to wrap packaging material 116 around load 124. As embodied herein and shown in
As shown in
Rotatable turntable 122 may further include a packaging material holder assembly 110, shown in
Clamp 111 for holding and releasing packaging material 116, as shown in
Other alternative embodiments of packaging material holder 110 may include other arrangements, such as a single unopposed packaging material engaging surface, or a sticky or tacky surface for holding the packaging material, or in some instances, a vacuum surface. Preferably, clamp 111 includes means for weakening packaging material 116, as shown in
For example, packaging material weakener 115 may include an opposed cutting element such as scissors, or a single cutting element such as a razor blade. Packaging material weakener 115 is activated to weaken packaging material 116 by cutting at least a portion of the web of packaging material 116, including the rope (not shown) of packaging material 116. Relative rotation between load 124 and dispenser 102 may create tension in the web of packaging material 116 extending in the film path between load 124 and dispenser 102. Continued relative rotation may cause packaging material 116 to tear or sever at its weakened region. Alternatively, other manners of tensioning the weakened film between load 124 and dispenser 102 may cause the weakened film to sever. It is also possible that packaging material weakener 115 may cut the entire web of packaging material 116, including the rope, to sever packaging material 116 without first weakening it. As used herein, the phrase “sever the packaging material 116” means to separate it into two portions, cutting through the entire width of packaging material 116.
Alternatively, packaging material weakener 115 may include a separately actuated device, such as a hot wire receiving power from a ground source. In such an embodiment, packaging material weakener 115 may cut through a portion of the web of packaging material 116, including the rope, to weaken packaging material 116 and/or cut through the entire web of packaging material 116 to sever packaging material 116. Alternatively, packaging material weakener 115 might cut through the entire web of packaging material 116 if the entire web of packaging material 116 has been roped to form a single rope of packaging material 116. Thus, packaging material weakener 115 may also serve as a severing means.
According to one aspect of the present invention, a means for securing a final tail of film to the wrapped load as the film web is severed between the load and the dispenser is provided. The means for securing the final tail includes a blower 160 that applies a broad stream of air 190 to the film web 116 to blow the film web 116 against the layers of film 116 on wrapped load 124. Blower 160 may be an “off the shelf” model, such as a shaded pole blower. Alternatively, any device or system capable of producing and directing a stream of air 190 toward load 124, such as for example an air compressor, may be used in place of blower 160. As embodied herein and shown in
As embodied herein and shown in
Blower 160 may be positioned such that the broad stream of air 190 it supplies substantially directly impacts corner 124a, “bisecting” corner 124a. By hitting corner 124a directly, it is possible to split or shear stream of air 190, such that at least a portion of stream of air 190a is directed upstream along the web of film 116 from corner 124a toward dispenser 102.
As embodied herein and shown in
In such an embodiment, when the broad stream of air 190 hits the side of load 124, the broad stream of air splits or shears, such that stream of air 190a is directed upstream along the web of film 116 from corner 124a toward dispenser 102. As embodied herein and shown in
Blower 160 is positioned sufficiently close to load 124 such that the broad stream of air 190 has sufficient force to press film web 116 against the layers of film 116 on load 124. Blower 160 is also positioned such that it does not interfere with any of the moving parts of wrapping apparatus 100. The structure of apparatus 100 and the type of means for providing relative rotation used, directly effect the positioning of blower 160. For example, when the means for providing relative rotation is rotatable turntable 122 upon which load 124 will be supported, box 162 containing blower 160 may be positioned directly adjacent to rotatable turntable 122 (see
Broad stream of air 190 supplied by blower 160 should provide sufficient force to push film web 116 extending along the film path between film dispenser 102 and corner 124a against load 124. In addition, as the film web 116 is severed between corner 124a and dispenser 102, broad stream of air 190 continues to push film web 116 against load 124, keeping film 116 flat and minimizing any spring back or curling up of final tail of film 152 as film web 116 is severed. Additionally, a stronger or faster stream of air may require less volume than a slower, or less forceful stream of air.
Blower 160 may be mechanically actuated or electrically actuated. It is possible that the rotation of turntable 122 or rotatable arm (not shown) may be utilized to actuate blower 160. Use of rotation of a turntable to actuate portions of a wrapping process or cycle is taught in U.S. Pat. No. 6,269,610 and U.S. Pat. No. 6,185,900, both of which are incorporated herein in their entirety.
As embodied herein and shown in
Although less preferred, it is also possible that blower 160 is not actuated until the film severing process either begins or has finished. In such an embodiment, the force and angle of the stream of air would require careful positioning to ensure that final tail of film 152 is pressed against wrapped load 124.
According to one aspect of the invention, a means for securing an initial tail of film to a load during wrapping also may be provided. The means for securing initial tail of film 150 to load 124 during wrapping may include a tail sweep plate 140. As embodied herein and shown in
Tail sweep plate 140 may be positioned such that it slopes slightly downward toward an outer edge or outer perimeter of rotatable turntable 122. This slight downward slope enhances the “sweeping” of initial tail 150 by the web of packaging material 116 as it passes over plate 140. Alternatively, plate 140 may be positioned substantially flat, and an outer edge of plate 140 may be beveled to provide the desired enhanced sweeping affect by “ramping up” packaging material 116 to the top of plate 140. Plate 140 preferably is positioned immediately above a bottom surface 116a of the web of film 116 extending between dispenser 102 and load 124. An example of a preferred distance that plate 140 is positioned above bottom surface 116a of the web of film 116 is about one quarter (¼) inch. Other distances may be used so long as plate 140 is elevated sufficiently to allow bottom surface 116a of the web of packaging material 116 to move over plate 140 and sweep up initial tail 150 as web 116 moves over plate 140. As web 116 “sweeps up” initial tail 150, it moves into contact with wrapped load 124 or a fixed wrapping structure, as will be described below, and thereby secures initial tail of film 150 to packaging material 116 wrapped around load 124.
Alternatively, blower 160 may be used to secure initial tail of film 150 to load 124. For example, should the distance between plate 140 and bottom 116a of film web 116 be too great for film web 116 to “sweep up” initial tail of film 150, blower 160 may be used to secure initial tail of film 150 to packaging material 116 around load 124. The tilt of plate 140 will permit stream of air 190 supplied by blower 160 to lift initial tail of film 150 off of plate 140 and press or push it into the layers of film 116 overwrapping load 124 (or a fixed wrapping structure as will be described below). In such an embodiment, it may be desirable to actuate blower 160 before rotatable turntable 122 is entering its last revolution of the wrapping cycle. By actuating blower 160 at an earlier point in the wrapping cycle, initial tail of film 150 may be overwrapped by additional layers of film 116 prior to severing of film web 116 at the end of the wrapping cycle.
The means for securing the initial tail of film may also include a fixed wrapping structure to which a portion of the initial tail of film may be fixed. As shown in
In an exemplary embodiment, fixed wrapping structure 130 extends along substantially the entire length of packaging material holder 110. Fixed wrapping structure 130 may have any shape that permits overwrapping of structure 130 with packaging material 116 without interference from packaging material holder 110 or clamp 111 when clamp 111 is in its wrapping position (i.e., holding a portion of packaging material 116). It should be understood that different types of clamps/packaging material holders may be used with fixed wrapping structure 130, and therefore, the shape of structure 130 may vary according to the type of clamp used.
Fixed wrapping structure 130 permits leading end 30 of packaging material 116, when held by clamp 111, to pass over a top surface of fixed wrapping structure 130 to engage corner 124a of load 124. For example, if one were to picture corner 124a as a point on a clock, clamp 111 holding leading end 30 would form the center of the clock, and packaging material 116 extending between the two would form the hand of the clock. In such an example, it is preferable that corner 124a be positioned between twelve o'clock and two o'clock. Therefore, fixed wrapping structure 130 must extend sufficiently proximally (i.e., toward dispenser 102) to allow film 116 to pass over structure 130 to corner 124a in this position. However, fixed wrapping structure 130 cannot extend so far proximally that it interferes with web of film 116, resulting in a load that is not wrapped tightly.
Preferably, fixed wrapping structure 130 extends about two inches above bottom surface 116a of web of packaging material 116 extending between load 124 and dispenser 102. Bottom surface 116a of web of packaging material 116 may be a lower edge of web of packaging material 116, or it may be a roped portion (not shown) of packaging material 116. Specifically, fixed wrapping structure 130 must be elevated sufficiently to allow packaging material 116 to overwrap it during wrapping cycle, thereby securing the initial tail of film 150 to load 124.
As shown in
The metal plate may be attached to rotatable turntable 122 and may extend vertically upward from rotatable turntable 122. The metal plate of fixed wrapping structure 130 may be fixedly connected to rotatable turntable 122 or hingedly connected to facilitate easier removal of the overwrapped packaging material 116 from fixed wrapping structure 130 after wrapping. In an apparatus in which a fork truck or other means is used to lift load 124 off of a wrapping surface, fixed wrapping structure 130 need not be movable with respect to rotatable turntable 122.
However, in a conveyor situation, for example, where load 124 will be pushed off the wrapping surface, fixed wrapping structure 130 may be movable with respect to the wrapping surface to allow fixed wrapping structure 130 to be moved from between packaging material 116 and load 124. This may be accomplished by, for example, the use of hinges. If hinges are used, the hinges may require a certain amount of force, such as fixed wrapping structure 130 being pushed, to cause fixed wrapping structure 130 to move with respect to the wrapping surface. This may prevent premature release of packaging material 116. This embodiment may be particularly suitable for use with the non-powered conveyor and pusher system disclosed in U.S. patent application 09/985,156, filed on Nov. 1, 2001, and entitled “Method and Apparatus for Wrapping a Load,” the entire contents of which is incorporated herein by reference.
Fixed wrapping structure 130 has the added benefit of protecting packaging material holder 110 from loading equipment when load 124 is being placed on or removed from the load support surface of rotatable turntable 122. For example, it is common to use forklift trucks to place loads onto rotatable turntable 122 prior to wrapping. Fixed wrapping structure 130 prevents the forks of the forklift truck from inadvertently coming into contact with and damaging packaging material holder 110. Fixed wrapping structure 130 also protects packaging material holder 110 from load 124.
Fixed wrapping structure 130 includes a top surface 133 extending between two end portions 132 and 134. Two end portions 132 and 134 of fixed wrapping structure 130 are referred to as the proximal and distal end portions respectively, of fixed wrapping structure 130, with respect to their positions relative to packaging material dispenser 102.
Proximal corner 132 of fixed wrapping structure 130 may include a film release bar 138. As embodied herein, film release bar 138 may be a simple steel or aluminum bar. A first end of film release bar 138 is connected to proximal corner 132 of fixed wrapping structure 130. A second end of the film release bar 138 is connected to rotatable turntable surface 122. Preferably, film release bar 138 is slightly angled between fixed wrapping structure 130 and turntable surface 122. This incline permits film 116 to slide off of proximal corner 132 of fixed wrapping structure 130 when load 124 is being removed from turntable 122 after wrapping. If fixed wrapping structure 130 is hingedly connected to turntable 122, it is not necessary to provide film release bar 138.
Blower 160 may be used alone to secure final tail of film 152, in conjunction with plate 140 to secure initial tail of film 150 and final tail of film, in conjunction with fixed wrapping structure 130 to secure final tail of film 152, or in conjunction with both plate 140 and fixed wrapping structure 130 to secure initial tail of film 150 and final tail of film 152. Other variations and combinations of the various elements described herein are also within the scope of the present invention.
According to another aspect of the invention, a roper may be provided for forming a rope of packaging material. As discussed herein, “roping” packaging material means rolling or twisting or collapsing a portion of the web of packaging material 116 to shape it into a rope-like form. In order to withstand a starting force during wrapping, at least 20% of the web of packaging material 116 should be held by packaging material holder 110. For example, a web of packaging material 116 twenty (20) inches high may have a five (5) or six (6) inch portion formed into a rope. This allows jaws 112 and 114 to engage a rope (not shown) and a portion of web of packaging material 116, rather than holding only a small portion of the packaging material 116 between the opposing surfaces. As seen in
Leading end 30 of packaging material 116 held by clamp 111 forms initial tail of film 150 when it is released. When packaging material 116 is severed or torn between load 124 and dispenser 102 at the end of the wrap cycle, trailing end 32 of film 116 forms final tail of film 152. Blower 160 or film web 116 sweeps initial tail of film 150 off of plate 140 and causes it to adhere to the previous layers of film 116 (on either load 124 or fixed wrapping structure 130). Blower 160 supplies broad stream of air 190 to film web 116 extending along a film path between corner 124a of load 124 and dispenser 120, and as packaging material 116 is severed between dispenser 102 and corner 124a of load 124, final tail of film 152 is pressed against wrapped load 124 (or overwrapped fixed wrapping structure 130) by steam of air 190, and adheres to the previous layers of packaging material 116, thus securing final tail of film 152 to packaging material 116 around the load 124.
A method of securing final tail of film 152 to load 124 will now be described. Load 124 to be wrapped is placed on a load support surface of rotatable turntable 122 or is placed on the floor or other support surface adjacent to packaging material holder 110 or a rotatable arm (not shown) supporting film dispenser 102. If fixed wrapping structure 130 is provided, load 124 is placed near fixed wrapping structure 130. Initially, film clamp 111 holds leading end 30 of the web of packaging material 116, which extends between clamp 111 and dispenser 102, over tail sweeping plate 140. Relative rotation is provided between load 124 and the dispenser 102 either by rotating turntable 122 or by rotating the rotatable arm supporting film dispenser 102 around load 124. As the relative rotation is provided, packaging material 116 is dispensed from dispenser 102 and wrapped around load 124. Dispenser 102 moves vertically upward on mast 104 or on the rotatable arm.
Dispenser 102 then moves down mast 104 or the rotatable arm, continuing to wrap load 124 as relative rotation between load 124 and dispenser 102 is provided. When dispenser 102 reaches the bottom of mast 104 or the rotatable arm, the wrapping cycle enters its last revolution. As the wrapping cycle enters its last revolution, blower 160 is actuated and supplies the broad stream of air 190 that engages film web 116 as it extends along a film path between dispenser 102 and corner 124a of load 124. Film clamp 111 then is actuated to grasp packaging material 116 between corner 124a and dispenser 102, and to weaken packaging material 116 between corner 124a and dispenser 102 while turntable 122 (or rotatable arm) continues to rotate slowly, and blower 160 continues to supply stream of air 190 directed onto film web 116, pushing film web 116 into the side of the load 124. As film web 116 is weakened, blower 160 continues to supply stream of air 190, and when film web 116 is severed between corner 124a of load 124 and dispenser 102, final tail of film 152 is pressed against wrapped load 124 (or overwrapped fixed wrapping structure 130) by stream of air 190 supplied by blower 160, and final tail of film 152 adheres to packaging material 116 such that final tail of film 152 is secured to packaging material 116 wrapped around load 124.
A method of securing initial tail of film 150 and final tail of film 152 will now be described in accordance with the present invention. The method will be described for use with rotatable turntable 122, however, a rotatable arm supporting film dispenser 102 could be used instead. Additionally, the method will be described using fixed wrapping structure 130, however, the method can be practiced without the use of fixed wrapping structure 130.
Load 124 to be wrapped is placed on a load support surface of rotatable turntable 122. Load 124 is placed near fixed wrapping structure 130. Initially, film clamp 111 holds leading end 30 of the web of packaging material 116, which extends between clamp 111 and dispenser 102, over tail sweeping plate 140. Relative rotation is provided between load 124 and dispenser 102 by rotating turntable 122. As load 124 and turntable 122 rotate, packaging material 116 is dispensed from dispenser 102 and wrapped around load 124. During the first rotation of turntable 122, packaging material 116 overwraps fixed wrapping structure 130, such that fixed wrapping structure 130 is between load 124 and a first layer of packaging material 116. If bottom surface 116a of film web 116 moves over a roper, such as wheel 145, bottom portion 116a of web 116 may be formed into a rope portion (not shown). As bottom surface 116a of the web of film 116 (or rope portion) moves over tail sweeping plate 140, it overwraps the portion of packaging material 116 extending from clamp 111, and secures it to fixed wrapping structure 130.
As the rotation of turntable 122 continues, dispenser 102 travels vertically upward on mast 104 to wrap packaging material 116 around load 124. While dispenser 102 is at the top of mast 104, turntable 122 slows and packaging material clamp 111 may be actuated or opened to release leading end 30 of packaging material 116. When clamp 111 releases leading end 30, initial tail 150 is formed and will lie on tail sweeping plate 140. In this embodiment, leading end 30 is released while dispenser 102 is at the top of mast 104 in order to prevent interference between clamp 111 and the web of film 116. It should be understood that the releasing step may occur at any point in the wrap cycle after a portion of initial tail 150 has been secured to fixed wrapping structure 130 while clamp 111 holds leading end 30 of packaging material 116. It is contemplated that other types of clamps may be used such that interference between clamp 111 and the web of film 116 is not an issue, and in such a case, leading end 30 may be released at a different point.
Dispenser 102 then moves down mast 104, continuing to wrap load 124 as turntable 122 rotates. When dispenser 102 reaches the bottom of mast 104, bottom surface 116a (or the roped portion) of the web of film 116 slides over tail sweeping plate 140, gathering or “sweeping up” initial tail of film 150 from plate 140 and securing it to the previous layer of film 116 overwrapping fixed wrapping structure 130. Initial tail of film 150 may be overwrapped more than once if so desired. Thus, initial tail of film 150 is secured between at least two layers of packaging material 116. Alternatively, bottom surface 116a of film web 116 may not sweep up initial tail of film 150. In such an embodiment, blower 160 is actuated as turntable 122 enters its final revolution of the wrapping cycle. As sweeping plate 140, with initial tail of film 150 lying on it, rotates past blower 160, broad stream of air 190 supplied by blower 160 lifts or pushes initial tail of film 150 off of plate 140 and pushes/presses it against film web 116 overwrapping fixed wrapping structure 130, thus securing initial tail of film 150 to the load 124. If it is desired to overwrap initial tail of film 150, blower 160 may be actuated prior to the last revolution of the wrapping cycle such that a desired number of overwrapping layers of film web 116 may be applied before film web 116 is severed.
As turntable 122 enters the final revolution of the wrapping cycle, blower 160 is actuated and directs broad stream of air 190 (heated or unheated) toward load 124 to engage film web 116 as it extends along a film path between dispenser 102 and corner 124a of load 124. Film clamp 111 then is actuated to grasp packaging material 116 between corner 124a and dispenser 102 and to weaken packaging material between the corner 124a and dispenser 102, while turntable 122 continues to rotate slowly and blower 160 continues to supply stream of air 190 directed onto film web 116, pushing film web 116 into side of load 124. As film web 116 is weakened, blower 160 continues to supply stream of air 190 , and when film web 116 is severed between corner 124a and dispenser 102, final tail of film 152 is pressed against the overwrapped fixed wrapping structure 130 by stream of air 190 supplied by blower 160. Final tail of film 152 adheres to packaging material 116 such that final tail of film 152 is secured to packaging material 116 wrapped around load 124.
Once the wrapping of load 124 is complete, load 124 must be removed from turntable 122. If fixed wrapping structure 130 was used, load 124 may be lifted off of fixed wrapping structure 130. As load 124 is moved, film release bar 138 allows film 116 to slide off of proximal corner 132 of fixed wrapping structure 130 and into contact with load 124.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.
Claims
1. A method of securing a final tail of film to a load while wrapping the load with a film web, comprising:
- positioning the load on a load support surface;
- dispensing the film web from a dispenser;
- providing relative rotation between the load and the dispenser to wrap the film web around the load;
- applying a stream of air to engage the film web as the film web extends along a film path between a corner of the load and the dispenser;
- severing the film web between the corner of the load and the dispenser to produce the final tail of film; and
- securing the final tail of film to the load with the stream of air.
2. The method of claim 1, further including severing the film web while applying the stream of air to the film web.
3. The method of claim 1, further including weakening the film web between the corner of the load and the dispenser while applying the stream of air to the film web.
4. The method of claim 1, further including both weakening the film web between the corner of the load and the dispenser and severing the film web while applying the stream of air to the film web.
5. The method of claim 1, wherein applying the stream of air to engage the film web includes actuating a blower as a last revolution of a wrapping cycle is entered.
6. The method of claim 1, wherein applying the stream of air to engage the film web includes actuating a blower prior to severing the film web.
7. The method of claim 3, wherein severing the film web includes tensioning the weakened film web between the dispenser and the corner of the load.
8. The method of claim 7, wherein tensioning the weakened film web includes providing relative rotation between the dispenser and the load.
9. A method of securing a final tail of film to a load while wrapping the load with a film web, comprising:
- positioning the load on a load support surface;
- dispensing the film web from a dispenser;
- providing relative rotation between the load and the dispenser to wrap the film web around the load;
- applying a stream of air to engage the film web as the film web extends along a film path between a corner of the load and the dispenser;
- while applying the stream of air to the film web, severing the film web to produce the final tail of film; and
- securing the final tail of film to the load with the stream of air.
10. The method of claim 9, wherein applying the stream of air to engage the film web includes actuating a blower as a last revolution of a wrapping cycle is entered.
11. The method of claim 9, further comprising weakening the film web between the corner of the load and the dispenser prior to severing the film web.
12. The method of claim 11, wherein severing the film web includes tensioning the weakened film web between the dispenser and the corner of the load.
13. The method of claim 12, wherein tensioning the weakened film web includes providing relative rotation between the dispenser and the load.
14. A method of securing a final tail of film to a load while wrapping the load with a film web, comprising:
- positioning the load on a load support surface adjacent to a fixed wrapping structure;
- dispensing the film web from a dispenser;
- providing relative rotation between the load and the dispenser to wrap the film web around the load and the fixed wrapping structure;
- applying a stream of air to the film web as the film web extends along a film path between a corner of the load and the dispenser;
- severing the film web between the corner of the load and the dispenser to produce the final tail of film; and
- securing the final tail of film to the overwrapped fixed wrapping structure with the stream of air.
15. The method of claim 14, further including severing the film web while applying the stream of air to the film web.
16. The method of claim 14, further including weakening the film web between the corner of the load and the dispenser while applying the stream of air to the film web.
17. The method of claim 14, further including both weakening the film web between the corner of load and the dispenser and severing the film web while applying the stream of air to the film web.
18. The method of claim 14, wherein applying the stream of air to engage the film web includes actuating a blower as a last revolution of a wrapping cycle is entered.
19. The method of claim 16, wherein severing the film web includes tensioning the weakened film web between the dispenser and the corner of the load.
20. The method of claim 19, wherein tensioning the weakened film web includes providing relative rotation between the dispenser and the load.
21. The method of claim 14, wherein applying a stream of air to the film web includes actuating a blower prior to engaging the film web with a cutting element.
22. An apparatus for securing a final tail of film to a load while wrapping the load with a film web, comprising:
- a film dispenser for dispensing the film web;
- means for providing relative rotation between the load and the dispenser to wrap the film web around the load;
- a blower configured to apply a broad stream of air to engage the film web as the film web extends along a film path between a corner of the load and the dispenser;
- a controller configured to actuate the blower prior to the apparatus entering a last revolution of a wrapping cycle; and
- means for severing the film web, subsequent to actuation of the blower, to form the final tail of film, the blower being configured to apply the stream of air to the final tail of film to secure the final tail of film to the load.
23. The apparatus of claim 22, wherein the means for severing includes a cutting element.
24. The apparatus of claim 22, further including a fixed wrapping structure positioned on a load support surface, wherein when the load is positioned adjacent the fixed wrapping structure, the film web is wrapped around the load and the fixed wrapping structure.
25. An apparatus for securing an initial tail of film and a final tail of film to a load while wrapping the load with a film web, comprising:
- a clamp for holding a leading end of the film web;
- means for providing relative rotation between the load and a dispenser to dispense the film web;
- a sweep plate positioned near the clamp for receiving a released leading end of the film web;
- means for securing the released leading end of the film web to the load;
- a blower configured to apply a broad stream of air to engage the film web as the film web extends along a film path between a corner of the load and the dispenser;
- a controller for actuating the blower prior to the apparatus entering a last revolution of a wrapping cycle; and
- a cutting element for forming the final tail of film, the blower being configured to apply the stream of air to the final tail of film to secure the final tail of film to the load.
26. The apparatus of claim 25, wherein the means for securing the released leading end includes the blower.
27. The apparatus of claim 26, wherein the means for securing the released leading end further includes a fixed wrapping structure.
28. A method of securing an initial tail of film and a final tail of film to a load while wrapping the load with a film web, comprising:
- positioning the load on a load support surface;
- holding a leading end of the film web extending from a dispenser;
- providing relative rotation between the load and the dispenser to wrap layers of the film web around the load;
- releasing the leading end of the film web;
- securing the released leading end of the film web to the load;
- applying a stream of air to engage the film web as the film web extends along a film path between a corner of the load and the dispenser;
- severing the film web to produce the final tail of film; and
- securing the final tail of film to previously dispensed layers of film with the stream of air.
29. The method of claim 28, wherein the film web is weakened between a corner of the load and the dispenser prior to severing.
30. The method of claim 28, further including securing the initial tail of film to an outer layer of film wrapped around the load with the stream of air.
31. The method of claim 28, wherein positioning includes positioning the load adjacent a fixed wrapping structure.
32. The method of claim 31, wherein providing relative rotation includes wrapping the layers of the film web around the load and the fixed wrapping structure.
33. The method of claim 32, wherein securing the final tail of film includes securing the final tail of film to an outer layer of film overwrapping the fixed wrapping structure.
34. The method of claim 33, further including securing the initial tail of film to an outer layer of film with the stream of air.
35. A method of wrapping a load, comprising:
- positioning the load on a load support surface;
- dispensing a film web from a dispenser;
- providing relative rotation between the load and the dispenser to wrap the film web around the load;
- directing a stream of air at a corner of the load, wherein the film web extends between the corner of the load and the dispenser, wherein the stream of air impacts the corner of the load in a manner such that at least a portion of the stream of air engages the film web to push the film web toward the load;
- severing the film web between the corner of the load and the dispenser to produce a final tail of film; and
- continuing to direct at least a portion of the stream of air onto the film web until at least a portion of the final tail of film is substantially secured to the load.
36. The method of claim 35, further including securing at least a portion of the initial tail of film to the load with the stream of air.
37. The method of claim 35, further including applying the stream of air to engage the film web while weakening the film web prior to severing.
38. The method of claim 35, wherein the stream of air is directed at the corner of the load during the final revolution of the load.
39. The method of claim 35, further comprising weakening the film web between the corner of the load and the dispenser prior to severing.
40. The method of claim 39, wherein severing includes tensioning the weakened film web between the corner of the load and the dispenser.
41. A method of wrapping a load, comprising:
- positioning the load to be wrapped;
- dispensing a film web from a dispenser;
- providing relative rotation between the load and the dispenser to wrap the film web around the load;
- as a final revolution of the wrapping cycle begins, applying a stream of air to the film web as the film web extends between the corner of the load and the dispenser such that at least a portion of the stream of air engages the film web to push the film web toward the load; and
- continuing to apply the stream of air to the film web while severing the film web to produce a final tail of film.
42. The method of claim 41, wherein severing the film web includes weakening the film web.
43. The method of claim 42, further including using relative rotation between the dispenser and the load to sever the film.
44. The method of claim 41, further including applying the stream of air to an initial tail of film to push the initial tail of film toward the load.
45. The method of claim 42, wherein severing the film web includes tensioning the weakened film web between the dispenser and the corner of the load.
Type: Application
Filed: Nov 7, 2006
Publication Date: Jul 12, 2007
Inventor: Patrick Lancaster (Louisville, KY)
Application Number: 11/593,628
International Classification: B65B 11/04 (20060101);