Patent Grant
9994011
Candies, confectionaries, chewing gum, medicines, crackers, cookies, and small manufactured foods are designed small enough so that one or more may be placed in one's mouth for chewing or dissolving or swallowing whole. Such small objects often bear a marking, such as one or more letters and numbers. For example, a fictitious candy identified by a name beginning with the letter “A” may have a soft inner comestible candy enclosed in a relatively hard and rounded candy shell. On the face of the shell, the manufacturer of the candy may print the letter “A” to distinguish the manufacturer's candy from other candies with similar shapes. In a similar manner, medications may carry indicia to identify the manufacturer of the pill, the medication contained in the pill, or both.
Consumers often make judgments on the value of products based upon the packaging or appearance of the products. A consumer will likely notice the indicia on candy or medication. If the indicia are obscured or reflect broken type, the consumer may form an unsatisfactory opinion about the quality of the product or the competence of the manufacturer. Accordingly, manufacturers pay close attention to carefully printing indicia on their products and discard products with obscured, unclear or broken typeface.
Indicia may be obscured during printing by debris from broken objects or excess ink. For example, in an offset printing process, an engraved roller may have a rigid, engraved pattern of indicia that is transferred first to a blanket roller and then to a candy or medicinal tablet or capsule. During an offset printing process the engraved roller passes through an ink bath to ink indicia that appear as a raised surface on the engraved roller. The inked, engraved roller contacts and transfers its inked images to the blanket roller. The blanket roller is has a soft surface for receiving the inked indicia from the engraved roller and transferring the indicia to the candy or tablets. The candies or tablets are held in pockets of a web or other conveyor and carried past the blanket roller. One face of the candy or tablet is turned toward the blanket roller to receive the inked indicia. Those skilled in the art also refer to the blanket roller as the print roller. In either instance, those skilled in the art are referring to a roller with a pliable surface for receiving inked images from the rigid, inked surface of the engraved roller.
Candies, foods, and medicines may come in any one of a number of three dimensional shapes. The simplest shapes are items with opposite flat surfaces spaced from each other by a uniform thickness, in effect, a flat, cylindrical shape. The top and bottom surfaces normally have the same geometric shape which may be any polygon. Other shapes use opposing surfaces with the same curved surface, including and not limited to circles, ovals, and other multi-curved shapes. Such items may be referred to as pills, tablets, lozenges, troches, or capsules.
There are a number of problems encountered in printing indicia on small objects such as candies or pills. The objects are generally fragile and easily breakable. In the normal course of printing, the pressure of the blanket roller against the objects may crack one or more objects and debris from the cracked objects may adhere to the blanket roller and/or transfer to the engraved roller. Such debris will leave an imperfect imprint on one or more objects. Accordingly, manufacturers often must stop the printing process and have a worker clean the blanket roller and the engraved roller.
Cleaning the rollers requires little or no skill. It is normally a manual activity. In a typical cleaning operation, a worker stops the press and uses brushes and cleaning fluid to scrub the ink and debris from the rollers. The blanket roller requires frequent cleaning. During each cleaning, a worker shuts down the offset printing press and cleans the blanket roller. The engraved roller is cleaned less frequently. The cleaning operations are repetitive and boring. Although cleaning the rollers is very important to appearance of the final product, cleaning is often poorly performed. When cleaning is poor, more candies and medicines are rejected at final inspection, thereby reducing productivity and increasing costs of manufacture.
There are known methods and apparatus for cleaning flexographic printing plates. See, for example, prior U.S. Pat. Nos. 7,011,025 and 8,590,449, which are hereby incorporated by reference for all purposes. However, flexographic printing plates have flexible, raised indicia, rather than the hard indicia made of ceramic or steel that is used to print candies and medicines. Likewise, flexographic printing does not require a blanket roller of pliable material.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
Embodiments of the apparatus and method disclosed herein overcome one or more problems with the prior art by providing mechanisms and methods that perform one cleaning operation on the blanket roller and another, different cleaning operation on the engraved roller. The embodiments allow the manufacturer to continue to print candies and medicines while the press is running. The method and apparatus performs approximately five to six dry cleaning operations on the blanket roller. After the fifth or more cleanings of the blanket roller, the press stops and the embodiments perform a second, wet cleaning operation on the engraved roller. By providing a single cleaning apparatus that dry cleans the blanket roller during press operation and cleans the engraved roller only once for every five or six dry cleaning operations, the productivity of the manufacturer is enhanced. In addition, the controlled cleaning of the rollers by a machine provides consistent cleaning operations on the blanket roller and on the engraved roller. The overall quality of the cleaning process is improved so that fewer products are rejected for poor quality printing of the indicia.
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
Referring to
Referring to
Referring to
Referring to
A base structure 36 is operably secured to the frame 30. A double-acting three-position cylinder 38 is attached to the base structure 36 in a standard manner, such as by bolts 40 shown in
A roll 54 of cloth 58 is carried by an unwind spindle 56. The cloth 58 is coursed from the roll 54 to underneath, in front and on top of the base structure 36 and wound around a rewind spindle 60 driven by a motor 62. The rewind spindle 60 is driven by the motor 62 by conventional means such as belt 72, shown in dashed lines. A low cloth sensor 64 provides an alarm when the supply cloth roll 54 is nearly used up. The sensor 64 includes a pivoting arm 66 with one end in engagement with a used roll 68 and the other end being associated with a switch 70. As the used roll 68 increases in diameter, the arm 66 pivots radially, eventually activating the switch 70 to send an alarm to a controller when the used roll 68 reaches a certain diameter indicative of the cloth roll 54 being nearly used up. For some embodiments, the low cloth sensor 64 is further described in U.S. Pat. No. 5,519,914. In such embodiments, the cloth 58 is a highly absorbent “clean room” grade, 100% woven polyester linen available from Lymtech Scientific, Chicopee, Mass. under the designation Purity Wipes. However, other cloths including non-woven material may be used in alternate embodiments.
Referring to
Referring to
The cylinder 38 comprises chambers 78 and 80 separated by a wall 82. A piston 84 with a piston rod 86 is disposed in the chamber 78. A piston 88 and its associated piston rod 90 are disposed within the chamber 80. The piston rod 86 extends through an opening in the wall 82 and engages the piston 88. The piston rod 90 extends through an opening through an end wall 92 and through an opening in a bottom wall 94 of the recess 44. A bolt 96 or other standard means secures the piston rod 90 to the backing plate 46. An end wall 98 encloses the chamber 78. Fluid inlet port 100 communicates with the chamber 78 and inlet ports 102 and 104 with the respective chamber 80, as best shown in
The cylinder 38 has a fully retracted position, as shown in
When pressurized fluid, such as compressed air, is supplied to fluid inlet port 100, the piston 84 moves to the wall 82, and pushes the piston 88 to an intermediate position within the chamber 80, thereby pushing the backing plate 46 partway toward the blanket roller 4, causing the cloth 58 to make contact with the blanket roller 4 with sufficient pressure to wipe the blanket roller 4 or the engraved roller 3 as it turns with the respective support cylinders 6, 7. At this position, called the dry wipe mode, a very low air pressure, for example less than 20 psi, allows the sponge pad 48 and the cloth 58 to float over the surface of the plate 4. The dry wipe mode allows the cloth to lightly collect ink from the blanket roller and debris (hickies) from the roller surfaces, and allows a light, dry and continuous wiping of each roller, resulting in greatly improved printing quality without stopping the press to handle the blanket roller and without any cleaning fluid.
To clean the engraved roller 3, the printing operation is interrupted and the cleaner 2 is repositioned to urge the web 58 of cleaning material against the engraved roller 3. It is optional to provide one or more initial dry wipes of the engraved roller 3 before making a wet wipe. After the initial dry wipes are finished, the cleaner operates in its wet wipe mode.
The cleaner 2 traverses the surface of the engraved roller 3 while the roller is turning. The cleaner 2 may clean the engraved roller 3 in a wipe mode or a wash mode. In the wipe mode, the pressure applied to the web 58 and the cleaning fluid supplied to the web are less than the wet wipe mode. In a further optional operation, the cleaner 2 may provide one or more dry wipe modes.
During the wash mode, pressurized fluid is supplied to the fluid inlet port 102, the piston 88 moves to the end wall 92 and causes the backing plate 46 to move further towards the engraved roller 3, thus further depressing the sponge pad 48 and causing the bristles 50 to protrude through the weave of the cloth 58 and make contact with the engraved roller 3 to provide thorough scrubbing of the contoured surface of the engraved roller 3. At this position, more aggressive cleaning is provided by the bristles whenever the press is not in production. During the wash mode, a higher pressure, for example 30 psi, is supplied to the inlet port 102 to allow a greater force to be applied to the backing plate 46, urging the bristles to make more forceful contact with the plate. A higher fluid flow rate is also provided to the sponge pad 48 to allow a more thorough washing of the engraved roller 3, which is done offline when printing is not being performed. The wash mode thoroughly soaks the sponge pad to assist with the removal of dried ink from the surface of the engraved roller 3. Separate liquid control is provided for the wet wipe mode compared to the wash mode.
The various components of the cleaner 2 are controlled from a programmable controller 106. The inlet hose 52 for the cleaning fluid is connected to a solenoid valve 108 which in turn is connected to a liquid pressure vessel 110 with a level sensor 112 connected to the controller 106. The inlet fluid port 110 of the cylinder 38 is connected to a solenoid valve 114. The fluid inlet port 102 is connected to another solenoid valve 116, set at a higher pressure than the valve 114. The valves 114 and 116 are controlled from the controller 106. A compressor 118 supplies compressed air to the pressure vessel 110 and to the cylinder 38.
The operation of the cleaner 2 will now be described. Referring to
Under the dry wipe mode, the blanket roller width is selected at 120 to control the traverse distance of the cleaning head 10. The traverse speed for the cleaning head 10 across the blanket roller 4 is selected at 124. A cloth advance time is selected at 126 which determines the operation of the rewind motor 62 to draw a new, clean section of the cloth 58 over the sponge pad 48. After the cleaner 2 is started at 128, alarms are checked at 130 for “low cloth” from the sensor 64. The cleaning head 10 is then moved to the edge of the blanket roller 4 at 132, the cloth is advanced at the selected time at 134, and the sponge pad is extended to the intermediate position at 138 by operating the valve 114 to provide compressed air into the chamber 78. The cleaning head 10 then traverses the length of the blanket roller 4 at 142 while the traverse speed is adjusted based on the speed of the plate cylinder 6, as determined by the speed encoder 22. The cleaning head reverses direction at the end of the blanket roller 4 at 144 and dry cleans the roller as the cleaning head returns to the opposite end of the blanket roller 4. The cleaning head is then retracted at 146 by providing compressed air through the inlet port 104 into the chamber 80. The whole process may be repeated starting at 130 for as many times as desired until the operator exits at 148. In some embodiments, the dry wipe mode is set to cycle at predetermined times such as every ten minutes.
Prior to entering the wet wipe mode, the printing action is interrupted and the cleaner 2 is repositioned to be closely adjacent to the engraved roller 3. The engraved roller 3 is periodically cleaned less frequently than the blanket roller 4. In one embodiment, the engraved roller 3 is cleaned once every hour. During the wet wipe mode, the engraved roller 3 width is selected at 120 to control the traverse distance of the cleaning head 10. A liquid pulse time is selected at 122, which determines the amount of time the solenoid valve 108 is pulsed to inject the cleaning fluid to the sponge pad. The traverse speed for the cleaning head 10 across the engraved roller 3 is selected at 124. A cloth advance time is selected at 126 which determine the operation of the rewind motor 62 to draw a new, clean section of the cloth 58 over the sponge pad 48. After the cleaner 2 is started at 128, alarms are checked at 130 for “low cloth” from the sensor 64 or for a low liquid level from the sensor 112. The cleaning head 10 is then moved to the edge of the engraved roller 3 at 132, the cloth is advanced at the selected time at 134, the cloth is moistened at 136 by operating the valve 108 and the sponge pad is extended to the intermediate position at 138 by operating the valve 114 to provide compressed air into the chamber 78. The cleaning fluid is then pulsed at 140 by intermittently operating the valve 108, thereby injecting the cleaning fluid through the passageway 74 to the sponge pad 48. The cleaning head 10 then traverses the length of the engraved roller 3 at 142 while the traverse speed is adjusted based on the speed of the support cylinder 7, as determined by the speed encoder 22. The cleaning head is then stopped at the end of the engraved roller 3 at 144. The cleaning head is then retracted at 146 by providing compressed air through the inlet port 104 into the chamber 80. The whole process may be repeated starting at 130 for as many times as desired until the operator exits at 148.
The wash mode is similar to the wipe mode except that the cylinder 38 is extended to its fully extended position at 160. Each cycle can be repeated as many times as desired at 162 until the operator exits at 164.
In some embodiments, the engraved roller 3 is traversed one or more times in a dry wipe mode, followed by wet wipe mode, an optional wash mode, and concluded with one or more dry wipes.
Turning to
A stepper motor 222 moves a screw drive 224 up and down in the directions of arrow C of
Other embodiments of the cleaner may use fewer electronic controls and permit manual setting of travel piston pressure and liquid volumes. For example, where a user operates embodiments to apply a single mark, letter, or a combination of letters and numbers to a candy, tablet, lozenge or troche, the blanket (print) roller may be only 2-3 feet long and could be operated mostly manually with the operator setting minimal values such as the travel of the cleaner, the pressure of the backing plate and the volume of the cleaning fluid.
Other embodiments of the cleaner may be used to clean small, three dimensional objects of virtually any shape including simply shaped items with opposite flat surfaces spaced from each other by a uniform thickness or other shapes including top and bottom surfaces of any polygon as well as top and bottoms with opposite curved surfaces to form a sphere, an ovoid or other multi-curved shapes. Still other embodiments may be used with general purpose offset printing presses to clean rollers that print on surfaces of thin or thick substrates, including and not limited to paper, cardboard, and sheets of plastic.
In some embodiments, the pressure applied during dry cleaning the engraved roller is the same pressure applied while cleaning the blanket roller. In other embodiments, the pressure may be different, including more or less than the pressure applied to the blanket roller. In some embodiments, the pressure applied during the wet, wipe mode may be the same as the pressure applied during the dry cleaning mode, more pressure, or less pressure.
While preferred embodiments of the invention have been shown and described, modifications and variations may be made thereto by those of ordinary skill in the art without departing from the spirit and scope of the present invention. In addition, it should be understood that aspects of the various embodiments may be interchanged either in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to be limitative of the invention as further described in the appended claims. Those skilled in the art understand that other and equivalent components and steps may be used to achieve substantially the same results in substantially the same way as described and claimed.
This application is a division of U.S. patent application Ser. No. 14/522,373, filed Oct. 23, 2014, the disclosure of which is hereby expressly incorporated by reference herein in its entirety.
| Number | Name | Date | Kind |
|---|---|---|---|
| 4135448 | Moestue | Jan 1979 | A |
| 4555989 | Marass | Dec 1985 | A |
| 4920880 | Hara et al. | May 1990 | A |
| 4953252 | Akisawa | Sep 1990 | A |
| 4981078 | Dettinger | Jan 1991 | A |
| 5322015 | Gasparrini | Jun 1994 | A |
| 5367955 | Hara et al. | Nov 1994 | A |
| 5373789 | Waizmann | Dec 1994 | A |
| 5408930 | Loos | Apr 1995 | A |
| 5440986 | Braun | Aug 1995 | A |
| 5479857 | Braun | Jan 1996 | A |
| 5519914 | Egan | May 1996 | A |
| 5644986 | Gydesen | Jul 1997 | A |
| 5727470 | Kurzer et al. | Mar 1998 | A |
| 5758577 | Ebina | Jun 1998 | A |
| 5816161 | Nussel | Oct 1998 | A |
| 5842418 | Corrado et al. | Dec 1998 | A |
| 5918545 | Pym | Jul 1999 | A |
| 5964007 | Wisniewski et al. | Oct 1999 | A |
| 6196128 | Corrado et al. | Mar 2001 | B1 |
| 6386106 | Stanka | May 2002 | B1 |
| 6640712 | Corti et al. | Nov 2003 | B2 |
| 6645349 | Koivukunnas et al. | Nov 2003 | B1 |
| 6679601 | Pham et al. | Jan 2004 | B1 |
| 6694879 | Schuster et al. | Feb 2004 | B2 |
| 7011025 | Egan | Mar 2006 | B2 |
| 7754051 | Porco | Jul 2010 | B2 |
| 8590449 | Egan | Nov 2013 | B2 |
| 9156247 | Egan | Oct 2015 | B2 |
| 9302465 | Roberts | Apr 2016 | B2 |
| 20020000168 | Fuseki et al. | Jan 2002 | A1 |
| 20020038610 | Corti | Apr 2002 | A1 |
| 20040244618 | Egan | Dec 2004 | A1 |
| 20050061182 | Ebina et al. | Mar 2005 | A1 |
| 20060230963 | Birger | Oct 2006 | A1 |
| 20110197918 | Kasper | Aug 2011 | A1 |
| 20130192484 | Lieske | Aug 2013 | A1 |
| Number | Date | Country |
|---|---|---|
| 64-16657 | Jan 1989 | JP |
| 3-90945 | Sep 1991 | JP |
| 9-76473 | Mar 1997 | JP |
| 9-295398 | Nov 1997 | JP |
| 2001-162774 | Jun 2001 | JP |
| 2001-270087 | Oct 2001 | JP |
| 2008-062650 | Mar 2008 | JP |
| 9700173 | Jan 1997 | WO |
| 9746388 | Dec 1997 | WO |
| Entry |
|---|
| International Search Report and Written Opinion dated Dec. 28, 2010, issued in corresponding International Patent Application No. PCT/US2010/033813, filed May 6, 2010, 6 pages. |
| Japanese Patent Office Notice of Rejection dated Jan. 21, 2014, issued in corresponding Japanese Patent Application No. 2012-514963, filed May 6, 2010, 8 pages (English summary). |
| Number | Date | Country | |
|---|---|---|---|
| 20160355005 A1 | Dec 2016 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14522373 | Oct 2014 | US |
| Child | 15243502 | US |
