Patent Application
20180118392
The present invention relates generally to a floating platen system, and more particularly to a floating platen system for use in connection with a packaging system that forms bags from a tube stock continuous film media.
Some existing packaging systems are adapted for packaging products using a tube stock continuous film media, rather than a bag on a roll. For example, U.S. Pat. No. 5,956,929 to Yisha et al. (issued Sep. 28, 1999) describes such a packaging system, said patent fully incorporated herein by reference. In packaging systems using tube stock continuous film media a floating platen (also referred to as a “puck”) may be inserted into a tube formed by upper and lower layers of the media, in order to isolate the upper layer from the lower layer during a cutting operation. The cutting operation forms an opening in the media that is used to fill a package or bag with product. The platen is maintained generally stationary relative to the media, in alignment with a cutting blade, as the media advances through the processing path of the packaging system. Accordingly, the upper and lower layers of media respectively flow over and under the platen, as the media advances. As shown in
Some drawbacks have been observed with respect to the existing floating platen system disclosed in U.S. Pat. No. 5,956,929. In this regard, the floating platen system has “pinch points” that can impede movement of the media through the processing path, thereby resulting in misalignment of the media. For example, media 22 is pinched between the surface of tail portion 34 of floating platen 30 and the surface of locating roller 50 (see
The present invention addresses these and other drawbacks of the prior art to provide an improved floating platen system that eliminates pinch points.
In accordance with the present invention, there is provided a floating platen system for a packaging system that forms bags from a tube stock continuous film media, said floating platen system includes: (i) a platen having a first magnet; and (ii) a guide assembly having upper and lower guide members that are spaced apart to form a slot therebetween for receiving the platen, each of said upper and lower guide members having at least one magnet, wherein magnetic forces between the magnets of the guide assembly and the first magnet of the platen maintain the platen in a substantially stationary position within the slot.
In accordance with another aspect of the present invention, there is provided a floating platen for a packaging system that forms bags from a tube stock continuous film media, the floating platen comprising: (i) a front body portion; (ii) a rear body portion having a groove extending generally perpendicular to a longitudinal axis of the platen, said groove dimensioned to receive a cutting edge of a blade for cutting a layer of the media; (iii) a main body portion located between the front and rear body portions; and (iv) a magnet for maintaining the floating platen in a substantially stationary position in alignment with the blade.
An advantage of the present invention is the provision of a floating platen system that is adapted for use with media made of a wide variety of materials.
Another advantage of the present invention is the provision of a floating platen system that uses magnetic forces to maintain the floating platen in a substantially stationary position relative to the media.
Another advantage of the present invention is the provision of a floating platen system that is readily adapted for use with existing packaging systems for producing and filling bags using a tube stock continuous film media.
A still further advantage of the present invention is the provision of a floating platen system that is easily adapted for use with tube stock continuous film media having various dimensions.
These and other advantages will become apparent from the following description of illustrated embodiments taken together with the accompanying drawings and the appended claims
The invention may take physical form in certain parts and arrangement of parts, embodiments of which will be described in detail in the specification and illustrated in the accompanying drawings which form a part hereof, and wherein:
Referring now to the drawings wherein the showings are for the purposes of illustrating embodiments of the invention only and not for the purposes of limiting same,
Packaging system 10 is generally comprised of a supply roll 12 of continuous film media 20 (e.g., a metalized polymer, etc.); a floating platen system 200 comprised of a platen 210 and a guide assembly 310; a slit forming unit 60 for forming an opening for bag filling; a filling unit 90 for filling a bag with articles (e.g., food product); and a sealing/cutting unit 130 for sealing and cutting bags. A housing 14 houses platen system 200, forming unit 60, and sealing/cutting unit 130.
Supply roll 12 provides a supply of continuous film media 20 that is comprised of two plies of sheet media (i.e., an upper layer and a lower layer). The upper and lower layers are fused together at the peripheral edges thereof (i.e., at the two side edges) to form a hollow tube. Media 20 may also take the form of a uniform tubular sheet media having no seals, or one or more seals at the peripheral edges thereof. Top and bottom seals, which are needed to complete a fully formed bag, are provided by sealing/cutting unit 130, which is described in detail below.
Before media 20 is fed into housing 14 of packaging system 10, platen 210 of floating platen system 200 is inserted into the tube formed by media 20 in order to isolate the upper layer from the lower layer during a cutting operation. Accordingly, platen 210 is inserted between the upper and lower layers of media 20. As will be explained in detail below, magnets (located in platen 210 and guide assembly 310) are used to maintain platen 210 in a substantially stationary position relative to media 20. Platen 210 and guide assembly 310 are described in detail below.
A roller 50 is a free roller for guiding media 20 between supply roll 12 and floating platen system 200, as it advances through a processing path of packaging system 10.
Slit forming unit 60 forms a slit (i.e., opening) in the upper layer of media 20 to provide a top opening of a bag. Slit forming unit 60 is generally comprised of a blade 70 (e.g., a serrated or straight blade); a pair of spring-loaded L-shaped pressure feet 72; and a pneumatic actuator 74 for moving blade 70 between retracted and extended positions. In one embodiment, pneumatic actuator 74 is comprised of a conventional air cylinder/piston arrangement. When blade 70 is moved to the extended position it contacts the upper layer of media 20 to form a slit in the upper layer of the media, thereby forming the top opening of a bag. Pressure feet 72 hold media 20 in tension against platen 210, as blade 70 cuts the upper layer of media 20. A support surface 75 provides support for platen 210.
A drive roller 80 is driven by a stepper motor (not shown), and advances media 20 through the processing path. A guide roller 82 is a free roller which operates in conjunction with drive roller 80 to advance media 20. Accordingly, drive roller 80 applies a tension to the upper layer of media 20, while guide roller 82 applies an equivalent tension to the lower layer of media 20.
Filling unit 90 functions to both open a bag and fill the bag with articles. Filling unit 90 is generally comprised of a fixed funnel portion 92, a telescoping funnel portion 96, an air cylinder/piston 100, and an air tube (not shown). Fixed funnel portion 92 includes a top end 94 for receiving product to be placed into the bag. Telescoping funnel portion 96 includes an outlet, and is movable relative to fixed funnel portion 92. As telescoping funnel portion 96 is moved downward, it moves into the opening of the bag formed by slit forming unit 60. Product exits filling unit 90 through the outlet of telescoping funnel portion 96. Mounting brackets are provided to mount air cylinder/piston 100 to fixed funnel portion 92 and to attach the air cylinder/piston 100 to telescoping funnel portion 96. The air tube (not shown) extends along the inside of funnel portions 92 and 96. However, it should be noted that the air tube remains fixed relative to funnel portion 92. The air tube includes a tube fitting and a nozzle. The tube fitting is provided at the top end of the air tube for connection to a blower. The nozzle is provided at the bottom end of the air tube. The nozzle guides air (or other gas) into the bag. It should be appreciated that filling unit 90 may be attached to housing 14 or to an infeed or product dispensing device (not shown). In some configurations of packaging system 10, funnel portions 92 and 96 may be omitted.
Sealing/cutting unit 130 is generally comprised of a cutting block assembly 131 and a pressure bar assembly 140. Cutting block assembly 131 is similar in structure and operation to slit forming unit 60. In this regard, cutting block assembly 131 includes spring-loaded L-shaped pressure feet 138 and a serrated blade 136. Serrated blade 136 is provided to cut through the upper and lower layers of media 20 to separate a completely formed (and sealed) bag 30. L-shaped pressure feet 138 hold media 20 in tension against a pressure bar 141 of pressure bar assembly 140, which is described below. This tension aids the cutting of media 20 and improves the quality of seals formed therein. To form seals, cutting block assembly 131 also includes an upper heater bar 132 and a lower heater bar 134. Heater bars 132, 134 may take the form of cylindrical cartridge heaters, which are mounted in cutting block assembly 131. Upper heater bar 132 fuses the upper and lower layers of media 20 to form the bottom seal of a bag, while lower heater bar fuses the upper and lower layers of media 20 to form the top seal of a bag. A detailed description of the operation of packaging system 10 is provided below.
Pressure bar assembly 140 is generally comprised of pressure bar 141, a pair of arms 142, a bar 144, and a pneumatic actuator 146. Pressure bar 141 applies pressure to media 20 such that it is simultaneously pressed against blade 136 and upper and lower heat bars 132, 134. As a result, two seals and a cut are made simultaneously. Arms 142 attach pressure bar 141 to bar 144. Bar 144 is moved inward and outward by pneumatic actuator 146. Pneumatic actuator 146 may be comprised of a conventional air cylinder/piston arrangement.
With reference to
As best seen in
In the illustrated embodiment, platen magnet M is generally planar and has a square or rectangular-shape with a top side 252 and a bottom side 254, as best seen in
Guide assembly 310 is generally comprised of an upper guide member 320, a lower guide member 360, and a support structure that is comprised of mounting blocks 400A, 400B and brackets 410A, 410B. Mounting blocks 400A, 400B are respectively attached to brackets 410A, 410B, such as by welding. The upper and lower guide members 320, 360 are attached to the support structure such that the upper and lower guide members 320, 360 are spaced apart to provide a slot 315 therebetween that is dimensioned to receive platen 210 and allow media 20 to move through slot 315 as it travels along the processing path, as best seen in
In the illustrated embodiment, upper guide member 320 is comprised of a first plate 330 and a second plate 340, wherein first and second plates 330 and 340 are spaced apart to provide an opening therebetween. Likewise, lower guide member 360 is comprised of a first plate 370 and a second plate 380, wherein first and second plates 370, 380 are spaced apart to provide an opening therebetween. Opposite ends of plates 330, 340, 370, and 380 are respectively fixed to mounting blocks 400A, 400B by fasteners 312. Fasteners 312 extend through respective mounting holes 336, 346, 376 and 386 of plates 330, 340, 370 and 380. It will be appreciated that in an alternative embodiment, a single plate may be substituted for first and second plates 330, 340, and a single plate may be substituted for first and second plates 370, 380, thereby eliminating the openings between the plates.
First plate 330 of upper guide member 320 includes recesses 332 that are dimensioned to receive magnets M1 and M2; second plate 340 of upper guide member 320 includes recesses 342 that are dimensioned to receive magnets M3 and M4; first plate 370 of lower guide member 360 includes recesses 372 dimensioned to receive magnets M5 and M6; and second plate 380 of lower guide member 360 includes recesses 382 dimensioned to receive magnets M7 and M8.
In the illustrated embodiment, magnets M1-M8 are generally planar and have a square or rectangular-shape with a front side 262 and a rear side 264, as best seen in
In the illustrated embodiment of the present invention, magnets M1 and M4 are oriented substantially parallel to each other such that their respective front sides 262 face each other, and magnets M2 and M3 are oriented substantially parallel to each other such that their respective front sides 262 face each other. Front sides 262 of magnets M1-M4 have the same magnetic polarity. Likewise, magnets M5 and M8 are oriented substantially parallel to each other such that their respective front sides 262 face each other, and magnets M6 and M7 are oriented substantially parallel to each other such that their respective front sides 262 face each other. Front sides 262 of magnets M5-M8 have the same polarity. However, the magnetic polarity of front sides 262 of magnets M5-M8 is opposite the magnetic polarity of front sides 262 of magnets M1-M4. Therefore, if front sides 262 of magnets M1-M4 have north polarity, then front sides 262 of magnets M5-M8 have south polarity.
As best seen in
It should be appreciated that while an illustrated embodiment of the present invention relies on the use of magnet repelling forces, it also contemplated that the floating platen system of the present invention may also use magnetic attractive forces in substitution for all or some of the magnetic repelling forces. The attractive forces may be attractive forces between multiple magnets and/or between magnets and a metal attracted to magnets.
With reference to
Operation of packaging system 10 and floating platen system 200 will now be described in detail. First, platen 210 is inserted into the tube formed by the upper and lower layers of media 20, as best seen in
In accordance with one embodiment of the present invention, platen 210 is oriented within slot 315 such that top side 252 of platen magnet M faces toward magnets M1-M4 of upper guide member 320, and bottom side 254 of platen magnet M faces toward magnets M5-M8 of lower guide member 360. Furthermore, top side 252 of platen magnet M has the same magnetic polarity (e.g., north) as front side 262 of magnets M1-M4 of upper guide member 320, and bottom side 254 of platen magnet M has the same polarity (e.g., south) as front side 262 of magnets M5-M8 of lower guide member 360. By orienting platen 210 within slot 315 such that top and bottom sides 252, 254 of platen magnet M are respectively repelled by front sides 262 of magnets M1-M4 (upper guide member 320) and by front sides 262 of magnets M5-M8 (lower guide member 360), platen 210 is maintained in a substantially stationary position within slot 315 as media 20 moves through the processing path. Furthermore, the repelling forces between magnet M and magnets M1-M4 and magnets M5-M8 suspend platen 210 between the lower surface of upper guide member 320 and the upper surface of lower guide member 360, such that respective gaps are provided therebetween to allow the upper and lower layers of media 20 to flow around platen 210, as best seen in
Returning now to
As best seen in
The opening between first and second plates 330, 340 of upper guide member 320 facilitates visually locating platen magnet M in a region of slot 315 between magnets M1-M4 of upper guide member 320 and magnets M5-M8 of lower guide member 360.
Referring now to
Operation of packaging system 10 is controlled by an electronic control unit (not shown), which preferably includes a microprocessor. The control unit may be programmable via a user interface (not shown), which preferably includes a keypad, control panel, or the like. It should be appreciated that the control unit is programmable to operate in coordination and in communication with a product dispensing device for dispensing product to filling unit 90.
The foregoing describes specific embodiments of the present invention. It should be appreciated that these embodiments are described for purposes of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. For example, it is contemplated that the floating platen system of the present invention may be used in connection with packaging systems different from the packaging system illustrated herein. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.
