The present invention is generally related to the field of automated bag closure systems.
For many years, manufacturers have used plastic bags to package a wide variety of products. In some industries, it is desirable to provide a plastic bag that can be repetitively opened and sealed by the consumer. For example, bread is often enclosed in a plastic bag that is bound with a twist-tie. The twist-tie closure allows the consumer to open and close the bag multiple times, thereby extending the use of the bag for the life of the product.
Although twist-ties are favored for their inexpensive cost, competing closure mechanisms have also been employed. For example, plastic lock-tabs are frequently used to close plastic bags containing perishable bakery items. Lock-tabs are easy to apply and offer the packager a surface upon which information can be printed. While generally acceptable, lock-tabs are relatively expensive. As an alternative, manufacturers have employed tape closure systems in which the neck of the bag is captured by a piece of one-sided tape. Tape closure systems offer the cost benefits of twist-ties and the ability to print information on the closure provided by lock-tabs.
U.S. Pat. No. 7,484,342, entitled “Apparatus and Method for Automated Tape Closure” issued Feb. 3, 2009 to Jimmy Frazier and assigned to Burford Corporation discloses a tape closure device for securing the neck of a bag with an adhesive film and a non-adhesive backing. Although well-suited for many packages, the method and apparatus disclosed in the Frazier '342 patent are not easily configured for vertically oriented packages. Vertically oriented packages are commonly used for granular or pelletized products that would tend to fall out of horizontally oriented packages. For example, ice, dog food, produce, hard candy and pretzels are commonly packaged in vertically oriented bags.
Many prior art closure systems function by applying a hog ring around the neck of the vertically oriented bag. This method of closing vertically oriented bags suffers from several deficiencies. First, the metal hog ring presents a health risk if accidentally ingested or masticated. Second, the metal hog ring is incapable of bearing identifying indicia. As food contamination concerns arise, more emphasis is being placed on the ability to track food from information contained on packaging materials. Accordingly, there is a need for an improved closure system for vertically oriented bags and packages that overcomes these deficiencies of the prior art.
In presently preferred embodiment, the invention includes a method and apparatus for applying a tape closure to a bag. The preferred method includes the steps of securing a leading portion of a continuous length of adhesive tape to a contact surface of a taping arm configured for rotation in a first geometric plane and gathering the neck of the bag between first and second opposing plungers configured for rotation in the first geometric plane. The preferred method continues by moving the gathered neck of the bag against a trailing portion of the continuous length of adhesive tape and forcing the gathered neck of the bag and the trailing portion of the continuous length of adhesive tape into a notch in a receiving block sized to accept the neck of the bag. Once the neck of the bag is forced into the notch of the receiving block, the method continues by rotating the taping arm and the leading portion of the adhesive tape behind the neck of the bag. The method continues by closing the tape closure by wiping the leading portion of the adhesive tape onto the trailing portion of the continuous length of adhesive tape and severing the trailing portion of the continuous length of adhesive tape. The preferred method concludes by securing the continuous length of adhesive tape to the taping arm in preparation for a subsequent cycle of operation.
The invention also provides for a tape closure device configured to carry out the preferred method. The tape closure device is configured to secure the neck of a bag with an adhesive tape and is well equipped to tape the neck of vertically-oriented packages. The tape closure device preferably includes a main plate that has a closure receiving slot and a drive plate connected to the main plate. The drive plate includes a drive assembly receiving slot that is vertically aligned with the closure receiving slot. The tape closure device also includes a drive assembly attached to the drive plate, a tape feed assembly attached to the main plate, and a closure system attached to the main plate. The closure system of the tape closure device includes a front plunger configured for rotation about a first vertical axis, a back plunger configured for rotation about a second vertical axis, a taping arm configured for rotation about a third vertical axis and a receiving block positioned adjacent the closure receiving slot.
In accordance with a preferred embodiment, the present invention includes a tape closure system for use in conjunction with an automated packaging system. Although the preferred embodiment is disclosed for use in a bakery environment, it will be understood that the tape closure device could find utility in a wide variety of other applications.
Referring to
Turning to
The tape feed system 114 includes tape 118, a spool 120 and a drag arm 122 (shown in
The printer assembly 110 is preferably configured to print desired information (e.g., date, location, batch) on the tape delivered from the tape feed assembly 114. The printer assembly 110 includes a computerized printer 124 and a printer belt 126. Tape 118 passes between the printer belt 126 and a print head located on the printer 124. The printer 124 selectively imprints the tape 118 by pressing the print head against the tape 118 and printer belt 126. As the tape 118 advances through the printer 124, the tape 118 momentarily adheres to the printer belt 126, which rotates with the motion of the tape 118. The printer belt 126 is preferably manufactured from a silicone material that releases the tape 118 without adversely affecting tackiness.
Turning to
The proximity sensor assembly 130 includes a slide 142 and at least one proximity sensor 144. As the bag 102 passes through the drive gear 134 and passive gear 136, the bag 102 contacts the slide 142, which moves back with the motion of the bag 102. The movement of the slide 142 is detected by the proximity sensor 144. The proximity sensor 144 outputs a signal to a controller (not shown) to indicate the presence of the bag 102 in the correct position for closure. In response, the controller initiates a closure cycle. When the bag 102 is no longer in contact with the slide 142, it returns to its home position. The movement of the slide 142 to the home position causes the proximity sensor 144 to output a second signal to the controller indicating that the neck of the bag 102 has been removed from the closure system 116.
Turning to
The closure system 116 further includes a first drive cylinder 162 and a second drive cylinder 164. The drive cylinders 162, 164 are preferably configured as double-action, pneumatic cylinders that are configured for pivotal movement about a proximal end. The distal end of the first drive cylinder 162 is connected to the front plunger 146. With the extension and retraction of the first drive cylinder 162, the front plunger 146 pivots about first plunger pivot point 166.
The distal end of the second drive cylinder 164 is connected to a transfer linkage 168 that pivots around a transfer linkage pivot point 170. The free end of the transfer linkage 168 is in turn connected to a taping arm linkage 172. The taping arm linkage 172 includes a curved portion 174 and a rod 176. The curved portion 174 allows the taping arm linkage 172 to rotate through a line of action that passes through transfer linkage pivot point 170. The rod 176 of the taping arm linkage 172 is connected to the taping arm 150, which in turn pivots around taping arm pivot point 178. When the second drive cylinder 164 is extended, the transfer linkage 168 rotates in a counterclockwise direction, which causes the taping arm 150 to also rotate in a counterclockwise direction. Conversely, when the second drive cylinder 164 is retracted, the transfer linkage 166 and taping arm linkage 172 cause the taping arm 150 to rotate in a clockwise direction. In this way, the free end of the taping arm 150 can be made to swing back and forth in front of the receiving block 152 through the alternating extension and retraction of the second drive cylinder 164.
The back plunger 148 pivots about a back plunger pivot point 180 that is adjacent to the front plunger pivot point 166. In this way, the front plunger 146 and back plunger 148 rotate along similar arcuate paths. The back plunger 148 is connected to a spring loaded arm 182. The spring loaded arm 182 includes an internal stop 184. As the back plunger 148 rotates counterclockwise in response to contact with a bag 102, the spring loaded arm 182 compresses until the internal stop 184 is reached. Once the bag 102 is no longer in the mouth 160 of the back plunger 148, the spring loaded arm 182 extends until the internal stop 184 is reached in the opposite direction.
A transfer link 192 connects the cutter linkage 188 with the cutter arm 154. As the cutter linkage 188 rotates, the transfer link 192 transfers the rotational movement of the cutter linkage 188 to the linear, sliding movement of the cutter arm 154. When the second drive cylinder 164 extends at the end of a closure cycle, a spring (not shown) returns the cutter linkage 188 to a home position. A cutter linkage stop 194 limits the retraction of the cutter linkage 188 and cutter arm 154.
Turning to
The taping arm 150 optionally includes a spike 210 extending from the face adjacent the contact surface 208. The spike 210 protrudes slightly above the plane of the contact surface 208 and provides a mechanism for aggressively securing the tape 118. During use, the spike 210 punctures the tape 118 to aggressively grip the tape 118. The spike 210 ensures that the tape 118 is adhered to the contact surface 208 and advanced for the next bag 102. The spike 210 find particular utility in those applications in which the tape closure device 100 is used in wet environments which decrease the adhesive characteristics of the tape 118.
The operation of the tape closure device 100 will now be described with reference to the components within the closure system 116.
Once the neck of the bag 102 is gathered between the front and back plungers 146, 148 and held in the receiving block notch 202, the second drive cylinder 164 retracts, as shown in
Next, in
It is to be understood that even though numerous characteristics and advantages of various embodiments of the present invention have been set forth in the foregoing description, together with details of the structure and functions of various embodiments of the invention, this disclosure is illustrative only, and changes may be made in detail, especially in matters of structure and arrangement of parts within the principles of the present invention to the full extent indicated by the broad general meaning of the terms expressed herein. It will be appreciated by those skilled in the art that the teachings of the present invention can be applied to other systems without departing from the scope and spirit of the appended claims.
The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/246,408, filed Sep. 28, 2009, entitled Apparatus and Method for Automated Tape Closure For Vertically Oriented Packages, the disclosure of which is herein incorporated.
Number | Date | Country | |
---|---|---|---|
61246408 | Sep 2009 | US |