Patent Application
20170100851
The disclosure relates to a pin eject system in a rotary cutting die arrangement comprising a rotary die cutting cylinder and an anvil roll with a media passing therebetween. The rotary cutting die arrangement is used in the converting industry to cut parts from a media passing between the two cylinders. The pin eject system facilitates the separation of the cut part from the media.
In one aspect, the disclosure relates to a rotary die cutting cylinder of the rotary die cutting arrangement with a pin ejection feature in a die cavity. The ejector pins project through holes in the die ejection pin cavity. The pins are located in a cutting die area of the cutting cylinder and are biased outward by a compressible, springing core disposed in the bore of the rotary cutting cylinder. During cutting, the media is compressed in the cavity between the rotary cutting cylinder and the anvil roll, and cut. The portion of the media in the cavity pushes against the ejector pins and the pins retract through their holes in the die cavity against the compressible core. As the die cavity rotates away from the anvil roll, the pins move outward by the biasing force of the compressible core and eject the part (or die cut slug) from the cavity. Thus, the pin eject system prevents the build-up of small die cut slugs in die cavities of the die.
In another aspect, the disclosure relates to an anvil roll of the rotary die cutting arrangement with a pin ejection feature that cooperates with a die cavity of a rotary cutting cylinder to maintain the cut media within the die cavity or to separate the media from the cut media within the die cavity. In one example, when the anvil rotates, the pin eject feature of the anvil roll comes into register with die cavity of the rotary cutting cylinder. The pins project into a cutting die area of the cutting cylinder and are biased outward by a compressible, springing core disposed in the bore of the anvil roll. The ejector pins project through holes in the anvil roll outer surface and comes into register with the die cavity at selected points during cutting. As the media is compressed in the cavity between the rotary cutting cylinder and the anvil roll, and cut, the pins push the material into the die cavity. As another example, the pins may project outward from the anvil roll in areas outside of the die cavity during cutting. As the media is compressed in the cavity between the rotary cutting cylinder and the anvil roll, and cut, the pins push the material outside of the die cavity away from the material within the die cavity, thereby facilitating the removal of the die cut portion from the remaining portion of the media outside of the cavity.
More in particular, the disclosure is directed to the ejector pin that has features that facilitate the assembly of the pin with the cylinder.
In the example of the anvil roll with pin eject feature, the anvil may have the same general construction as the rotary die cutting cylinder shown in
The ejector pin 28 comprises an elongate member with proximal and distal ends 36,38. The pin proximal end 36 is configured to be received in the ejector pin locator hole 34 such that the pin distal end 38 projects from the outer surface of the cylinder body 24 in the cavity 26 when the pin 28 is installed with the rotary die cutting cylinder body. The pin proximal end 36 may have an enlarged diameter portion 40. For instance, as shown in the drawings, the enlarged diameter portion 40 may comprise an annular boss extending circumferentially around the pin proximal end. Other shapes and configurations may be used, such as tapers, hooks, spokes, tabs, tangs, radially extending lobes, etc. The enlarged diameter portion 40 may form a shoulder which engages an inner diameter surface of the rotary cutting cylinder to retain the pin in the ejector pin locator hole for instance as shown in
In accordance with one aspect of the disclosure, the pin 28 may be assembled with the cutting cylinder body 24 by forcing the pin into the ejector pin locator hole 34 from the outer diameter side of the cutting cylinder body instead of from the bore of the rotary die cutting cylinder body. The ejector pin locator hole 34 may cause compression of the proximal end 36 as the pin is introduced to the ejector pin locator hole. The ejector pin locator hole 34 may have slight lead-in taper to facilitate compression of the proximal end 36. In addition to or in the alternative to, the enlarged diameter portion 40 of the pin proximal end 36 may have a beveled or chamfered edge to facilitate compression of the proximal end when the pin is introduced to the ejector pin locator hole 34. While the drawings show two longitudinal slits 42 extending from the proximal end 36 through the enlarged diameter portion 40 and along a length of the pin, one slit or more than two slits may be provided. The number of slits and their length 44 and width 46 may be dimensioned to provide the proximal end 36 with sufficient resiliency to allow the proximal end to be compressed to a lesser diameter where the enlarged portion 40 of the proximal end slides through the ejector pin locator hole 34, and released to a released diameter where the enlarged portion expands outward to engage the rotary die cutting cylinder body 24, for instance, an inner diameter surface of the rotary die cutting cylinder body adjacent to the ejector pin locator hole. The pin material may also be selected for the same effects. The pin material and slot dimensions may be selected to allow the proximal end to elastically and springingly compress to a diameter to allow the enlarged diameter portion 40 to pass through the ejector pin locator hole 34, and once the pin proximal end enlarged diameter portion passes through the ejector pin locator hole to the inner diameter of the rotary die cutting cylinder, to elastically and springingly spring diametrical outward so that the enlarged diameter portion engages the rotary die cutting cylinder body. The pin material and slot dimensions may be selected to allow for some plastic deformation as the pin proximal end is compressed to a diameter to allow the enlarged diameter portion 40 to pass through the ejector pin locator hole 34. The amount of plastic deformation may be limited so that once the pin proximal end enlarged diameter portion passes through the ejector pin locator hole to the inner diameter of the rotary die cutting cylinder, the proximal end springs outward to retain the pin in the ejector pin locator hole. The pin material and slot dimensions may be selected to reduce the effects of the pin buckling as the pin is compressed along its length between the anvil roll and compressible core. While the pin proximal end is shown with outer surfaces generally co-axial with the center axis of the pin, the pin proximal may be outwardly flared to increase the springing tension of the pin proximal end once it passes though the ejector pin locator hole. While the pin is shown in a monolithic construction, the pin may be formed from one or more materials. For instance, the pin proximal end may be formed from materials that provide for more resiliency than the distal end. The proximal end may be formed from materials that have good spring capabilities and/or are sufficient to withstand buckling. The distal end may be formed from materials that limit the amount of adhesive that may be attracted to the distal end from the cut media.
One example of an 0.040″ Φ ejector pin may be as follows:
Another example of an 0.070″ Φ ejector pin may be as follows:
Another example of an 0.096″ Φ ejector pin may be as follows:
Another example of an 0.125″ Φ ejector pin may be as follows:
As described above, the pin proximal end 36 may compress to allow the enlarged diameter portion 40 to pass through the pin locator hole 34, and once the enlarged diameter portion passes through the hole, the enlarged diameter portion of the proximal end may extend outward to engage the cylinder body 24. In the alternative, the enlarged diameter portion of the pin proximal end may be plastically deformed once positioned past the pin locator hole so that the plastically deformed portion of the proximal end, may extend outward to engage the cylinder body 24. The pins may be removed by removing the compressible core from the bore of the cylinder body and pushing the pin through the ejector pin locator hole so that the pin distal end passes into the bore of the cylinder body. The pins may be mounted in an anvil roll in a like manner.
In accordance with another aspect of the disclosure, the ejector pins 28 may be supplied in a kit 60 together with a flexible die and/or rotary die cutting cylinder assembly 20 and/or anvil roll and/or its component parts. Operators using the rotary die cutting cylinder assembly 20 may access the kit 60 and be directed through instructions 62 for arranging the ejector pins 28 in one or more holes of the die cavity depending upon the type of die utilized. For an anvil roll, the operator may be directed through instructions to arrange the ejector pins 28 in one or more holes that match with the die cavity, or are outside of the die cavity, depending upon the type of anvil roll and rotary die cutting cylinder utilized. The instructions may include text or other indicia directing use of the ejector pins 28, a flexible die, and/or rotary die cutting cylinder assembly 20 and/or anvil roll and/or its component parts. The ejector pins 28 may be sold separately, in the kit 60, or distributed together with the rotary die cutting cylinder assembly, anvil roll, compressible core, and/or flexible die. The ejector pins may be sold separately and provided with sufficient instructions directing the user to insert the ejector pins in the die cavities of the rotary die cutting cylinder or anvil roll as described previously. In connection with the sale or distribution of ejector pins, flexible die, or compressible core, the user (e.g., a purchaser of the ejector pins) is instructed that the purpose of the ejector pins, flexible die, or compressible core, is to remove, and install the components in a rotary die cutting cylinder and/or anvil roll as described previously. Thus, the user is induced to replace, remove, and install the components in a rotary die cutting cylinder and/or anvil roll as described previously.
As is seen in the foregoing description, the pin and its method of installation allow for maintaining the concentricity of the die which contributes to the quality of the products being produced by the process. The pin and its method of installation are versatile and allow for use in a variety of different die and rotary cutter configurations, for instance, cutting blade size and dimensions, ejector pin hole locations and sizes, cylinder diameters, and differently shaped die cavities and ejector pin sizes. The pin also has less tendency to be adversely affected by adhesive. The pin is relatively inexpensive to manufacture and may be easily assembled with the die cutting cylinder.
The embodiments were chosen and described in order to best explain the principles of the disclosure and their practical application to thereby enable others skilled in the art to best utilize the disclosed embodiments and with various modifications as are suited to the particular use contemplated. As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.
