The invention relates to the manufacturing and handling of packaging materials, and more particularly to a device for handling inflatable air cushions that are used as packaging material.
Devices are known for inflating flexible structures, such as inflatable air cushions or pillows (hereinafter referred to as “cushions”) that are used for filling empty space in a package to provide protection to an object during packaging and transportation thereof. One example of an inflation and sealing device is disclosed in U.S. Pat. No. 6,932,134. The device disclosed therein uses a set of drive rollers and a belt assembly to guide an inflation channel formed in the preconfigured film over an inflation assembly and a sealing assembly to 15 form cushions in the preconfigured film. The inflation channel is then cut free from the inflation nozzle using a fixed blade located downstream of the inflation and sealing assemblies.
U.S. Pat. No. 6,209,286 discloses an inflation and sealing device for forming packaging cushions that uses a fixed blade to cut the inflated cushions free from the inflation assembly after sealing of the cushions. A cutter is also shown for cutting along perforations in the inflated film to separate individual cushions. U.S. Publication No. US 2006/10292320 also discloses using a fixed blade to cut open the inflation channel.
An improved cutting mechanism is needed for such devices.
The present invention relates to a film handling device. The device includes a driver configured for engaging a plastic film for driving the film along a path and a cutting element that is operable for rotating with respect to the film for slicing the film. In an embodiment, the film can include first and second overlapping layers associated for providing cushion cavities to seal a fluid therein for providing package cushions. In such an embodiment, 30 the cutting element can be operable for slicing open an inflation channel in the film. Alternatively, the handling device can include a plurality of traction members configured for engaging a chain of pre-inflated package cushions connected to each other end-to-end. In such an embodiment, the driving mechanism is operably associated with the traction members for drawing the chain from an input location to an output location from which the pillows are dispensed, and the cutting element is configured to separate adjacent cushions by detaching at 5 least one of the cushions from the chain. Further, the cutting element can be operable for linear motion in a direction perpendicular to the path to slice the film between adjacent package cushions.
Another embodiment relates to an inflatable-cushion inflation and sealing device. The device includes an inflation assembly configured for inflating with a fluid a cushion cavity disposed between first and second layers of film, the inflation assembly including a fluid conduit configured for longitudinal reception between first and second overlapping portions of an inflation channel adjacent to and in fluid communication with the cushion cavity. The device further includes a cutting element disposed proximate the fluid conduit and configured and oriented to cut open the inflation channel by a cutting motion that includes rotation thereof and a sealing assembly configured to seal the overlapping portions to each other and to form a longitudinal seal configured to seal the fluid in the cushion cavity.
Preferably the first and second overlapping portions are juxtaposed against one another on two sides of inflation channel and the cutting element is configured and oriented to cut open inflation channel to provide an exit from the channel for the conduit. In a preferred embodiment, the cutting element is in the form of a disk having a sharpened, substantially circular outer edge. The disk can be made from steal and can includes a treatment or coating on the outside edge to improve the hardness thereof. The cutting element can be affixed to a motor configured to cause the rotation of the cutting element.
In a further embodiment, the fluid conduit includes a recessed portion, and the cutting element is positioned relative to the fluid conduit so as to partially extend into the recessed portion. Further, the fluid conduit further can include an outlet configured for supplying fluid into the cushion cavity and an inlet for receiving a fluid to be supplied into the cushion cavity. The recessed portion is preferably disposed between the inlet portion and the outlet. Further, the fluid conduit can be configured such that the first overlapping portion extends over the recessed portion, and wherein a portion of the cutting element extends into the recessed portion so as to cut open the inflation channel in an area where the first overlapping portion extends over the recessed portion. For example, the cutting member can be in the form of a disk having a diameter of between about 0.7 inches and 2 inches, and the cutting member can extend into the recessed portion by a distance of between about 0 and 0.2 inches.
In a further embodiment the sealing assembly is configured for receiving the first and second overlapping portions and for cooperatively driving the overlapping portions along a sealing direction to form the longitudinal seal. The rotation of the cutter is preferably carried out in the sealing direction at a speed that is faster than the speed at which the overlapping portions are driven.
Another aspect of the present invention relates a method for inflating and sealing an inflatable cushion. The method includes inflating a cushion cavity disposed between first and second layers of film by directing a flow of a fluid through an inflation channel adjacent to and in fluid communication with the cushion cavity such that the fluid flows into the cushion cavity. The inflation channel is formed from two overlapping portions of the film that are juxtaposed with one another on two sides of the inflation channel. The method further includes cutting open the inflation channel using a rotating cutting disk, and sealing the overlapping portions to each other so as to form a longitudinal seal configured to seal the fluid in the cushion cavity.
Referring to
Film 10 has a first longitudinal edge 12 and a second longitudinal edge 14, both of which are preferably closed or joined. Film 10 has a lead end 6, and also includes generally transverse seals 16, which each include a line of weakness 18, such as perforations or a score line. Transverse seals 16 join a first film layer 20, such as a top layer, of the film 10 to a second film layer 22, such as a bottom layer, of the film 10 along the seals, and, together with the closed, second longitudinal edge 14, define an inflation cavity of each cushion 28. The first and second film layers 20,22 define a major surface or plane of the film 10. The transverse perforations 18 perforate the film 10 through the first and second film layers 20,22 to facilitate separation of each cushion 28 from each other. Other embodiments can have an inflation channel remote from the edge, such as in the center, for example to form inflated chambers on opposite sides of the inflation channel.
In an embodiment, first and second film layers 20,22 are attached to each other along the second longitudinal edge 14, but are unattached to each other along first longitudinal edge 12 prior to inflation. Such a configuration can be formed from a single layer of film material, a flattened tube of film material with one edge slit open, or two separate layers of film material. For example, the first and second film layers 20,22 can include a single sheet of film material that is folded over itself to define the attached second longitudinal edge 14 (i.e., “c-fold film”).
Film 10 has a width 15, and a perforation-to-perforation length 17, which may be selected depending on the particular type of cushion being manufactured. In the embodiment shown in
Referring to the embodiment of the inflation and sealing device shown in
Film support assembly 40 is preferably configured for supporting a bulk supply of film of uninflated cushions, such as a roll 11 shown in
As shown in
In the embodiment of
Inflation assembly 50 is preferably mounted to support 31, which includes a base 33. The inflation assembly 50 is positioned proximate sealing assembly 70, and is positioned within device 30 such that it is generally aligned with first longitudinal edge 12 and inflation channel 23 as film 10 is directed through device 30. Inflation assembly 50 is configured and oriented for inflating cushion cavities 28 of film 10 with air.
Inflation assembly 50 preferably includes a fluid conduit in the form of a nozzle 52. Nozzle 52 is connected at open end 51 to an air pump. Nozzle 52 is preferably tubular and extends in a longitudinal direction that is generally parallel to the downstream movement direction 35 of film 10. In a preferred embodiment, tip 54 of nozzle 52 has a tapered shape, although in other embodiments, tip 54 can have other configurations. Tip 54 is preferably smooth and rounded. As shown in
Nozzle 52 includes an outlet 56 from which inflation fluid is expelled to inflate the cushion cavities of film 10. Outlet 56 is preferably disposed near tip 54, but can alternatively or additionally be placed in different suitable locations. In the preferred embodiment, outlet 56 includes a lateral slot that extends along a portion of the longitudinal length of nozzle 52 and is positioned to direct air substantially transversely into the inflation channel 24 and the cushion cavities 28. Outlet 56 can have any suitable length. In an example, outlet 56 has a length that is longer than the perforation-to-perforation length 18 of film 10 to maximize the inflation efficiency of the air expelled from outlet 56 and into the cushion cavities. Preferably, cushions 28 are filled with air at an inflation pressure of at least about 3 psi, and more preferably at an inflation pressure of at least about 5 psi, and up to about 15 psi. In an example, the inflation pressure of cushions 28 is between about 5 psi and about 8 psi, but other inflation pressures can be used as desired. Nozzle 52 can include more than one outlet 56. In an example, a pair of outlets 56 is disposed diametrically opposite each other on the circumference of the nozzle. In another example, nozzle 52 includes three or more outlets 56 disposed around the circumference thereof.
The preferred inflation assembly 50 also includes a cutting device, which preferably a rotary cutter 58. Rotary cutter 58 has a disk-shaped cutting element 59 with a sharpened outer edge configured to rotate about axis 61. Cutting element 59 is preferably rotatably secured to support 31 such that it is partially disposed within slot 55 defined in the tubular wall of nozzle 52. Cutting element 59 extends into slot 55 by a distance 53 of at least about 0.01 inches. In a preferred embodiment, cutting element 59 extends into slot 55 by a distance of between about 0.03 inches 0.10 inches below the surface of the inflation nozzle 54. In an embodiment, cutting element 59 can extend into slot 55 by a distance of up to 0.25 inches. Slot 55 is preferably machined within the tubular wall avoiding or minimizing any leaks from nozzle 52. In an alternative embodiment, slot 55 can extend entirely through the wall of nozzle 52. Slot 55 is shown in
Cutting element 59 is affixed to the output end of motor 60 included in the rotary cutter 58 such that motor 60 causes cutting element 59 to rotate about axis 61 when device 30 is in use. Preferably, motor 60 causes cutting element 59 to spin in a direction such that the portion thereof that is disposed within slot 55 is moving substantially in downstream direction. The rotational speed of cutting element 59 is preferably selected to correspond to the thickness of film 10 and the desired feed rate of film 10 through sealing mechanism 70. As shown in
Nozzle 52 is preferably configured to fit within inflation channel 23 such that inflation channel 23 is at least slightly under tension. This arrangement, shown in
Rotary cutter 58 is preferably configured for cutting element 59 to cut film 10 after inflation of cushions 28 to allow film 10 to release nozzle 52, as shown in
The rotational cutting action used by rotary cutter 58, improves the speed at which inflation channel 23 can be cut over embodiments that used a fixed-blade arrangement for cutting. Accordingly, the feed-rate of film 10 in downstream direction 35 can be increased, allowing a higher number of cushions 28 to be inflated in a given period of time. For example, in a preferred embodiment of film 10, discussed above, having a length 17 of about 8 inches and a width of about 8 inches, the feed rate of film 10 can be about 50 and 20 feet per second. Further, the rotational cutting action of rotary cutter 58 allows for cutting of film 10 to be distributed along substantially the entire outside edge of the cutting element 59, rather than being limited to substantially a point along, for example, a fixed blade. This leads to increased blade life, which reduces cost and decreases downtime for replacing the cutting element.
In an embodiment, sealing assembly 70 can be similar to that which is described in U.S. Pat. No. 6,932,134 and is positioned within device 30 downstream from inflation outlet 56 of inflation assembly 50 so that cushions 28 of film 10 are sealed after being inflated. Sealing assembly 70 includes a first assembly portion 72 and a second assembly portion 74, between which film 10 is disposed. The preferred first and second portions 72,74 are arranged such that nozzle 52 is disposed vertically therebetween and horizontally and laterally beyond sealing portions 72,74 opposite from inflation cavity, as shown in
As film 10 moves in the downstream direction 35, belts 90A,90B cooperatively apply pressure and hold the film layers 20,22 against each other along the sealing assembly 70 sufficiently tightly to prevent air within the inflated cushion cavities from leaking during the rest of the sealing process. To provide a maximum pinching pressure between belts 90A, 90B and film layers 20,22, the spacing between belt 90A and belt 90B is preferably minimized. Preferably, belts 90A,90B.
After being pressed between belts 90A, 90B and either just before, just after or concurrently with being cut, film 10 is directed to sealing elements 120A,120B, which are positioned over a portion of belt 90B. Sealing elements 120A,120B are configured to produce a uniform seal with no gaps or pockets that would allow air to escape from the cushion cavities. Sealing elements 120A,120B are further configured and positioned to directly contact belt 90B and to press it down against film 10 therebelow. The heat transferred to film 10 through belt 90B is sufficient to melt or otherwise close and seal film 10.
To operate device 30, lead end 6 of film 10 is pulled from supply roll 11 and directed to inflation assembly 50. The inflation channel 23 is fed over the nozzle 52 of the inflation assembly 70 through lead opening 24. Lead end 6 of film 10 is then manually directed between belt 90A and belt 90B of the sealing assembly 70, where the sealing portion 8 of the film is pinched between pressure rollers 96A,96B. Once the gear and motor system associated with the pressure rollers 96A,96B is initiated and sealing surface 122 is heated, for example by turning on a power source of device 30, the remainder of the manufacturing process is automated, as film 10 is continuously pulled from supply roll 11 and directed to nozzle 52 for inflation, rotary cutter 58 for cutting, and sealing elements 120A,120B for sealing.
Various other embodiments of devices for inflating cushions 24 in a film 10 can be configured to replace a fixed-blade cutting mechanism with a rotary cutter 58 in accordance with the present invention. For example, commonly-assigned U.S. Provisional Patent Application No. 60/846,188 discloses a cushion inflating and sealing device that employs a rotary-sealing mechanism. The device further uses an inflation assembly having a nozzle with a fixed blade extending therefrom for cutting open the inflation channel of a film subsequent to inflation of cushions formed therein. Such a device can be outfitted with a rotary cutter as described herein to replace the blade associated with the inflation assembly. Similarly, commonly-assigned U.S. Provisional Patent Application No. 60/979,640 discloses a cushion inflating and sealing device with a disengagement mechanism. The device described therein uses an inflation assembly having a nozzle with a fixed blade extending therefrom for cutting open the inflation channel of a film subsequent to inflation of cushions formed therein. Such a device can be outfitted with a rotary cutter as described herein to replace the blade associated with the inflation assembly. In a similar manner, other cushion inflating and sealing devices can be outfitted with a rotary cutter of the present invention.
In addition to the mechanisms described herein, it will be appreciated that the device 30 can include various supplementary mechanisms and control functions. For example, the device 30 can include a central controller, a monitor, control signals, and feedback systems. Further, the device 30 advantageously requires only standard power utility requirements, such as by being capable of plugging into a standard wall outlet of 120 or 240 VAC, and 15 amp, and therefore can be operated with a simple on-off switch.
In a further embodiment, a embodiment of the rotary cutter described herein can be used in an automated pillow dispenser in order to facilitate the separation of an inflated film between adjacent pillows. An example of a dispenser device is disclose in U.S. patent application Ser. No. 11/867,452. In such an embodiment, shown in
All of the references specifically identified in the detailed description section of the present application are expressly incorporated herein in their entirety by reference thereto. The term “about,” as used herein, should generally be understood to refer to both the corresponding number and a range of numbers. Moreover, all numerical ranges herein should be understood to include each whole integer within the range.
While illustrative embodiments of the invention are disclosed herein, it will be appreciated that numerous modifications and other embodiments may be devised by those skilled in the art. For example, the features for the various embodiments can be used in other embodiments. Therefore, it will be understood that the appended claims are intended to cover all such modifications and embodiments that come within the spirit and scope of the present invention.
Number | Date | Country | |
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61077428 | Jul 2008 | US |