Patent Application
20060048619
1. Field of the Invention
The present invention relates generally to the manufacture of plastic containers, and more particularly to removing extraneous plastic from a manufactured container.
2. Related Art
Conventional high speed chipless cutters used, for example, in the manufacture of plastic containers, have a blade design that can cause a pull-back area to appear on the top surface of the bottle where the blade is pulled back across the surface of the finished cut after the cut is complete. This is especially true when the plastic of the container is at a high enough temperature that the plastic is soft.
As seen, for example, in
This pull-back area may deform the plastic container, in particular, the closing mechanism on top of the container. The pull-back area may also otherwise cause the container or the container closure not to operate properly. Improperly manufactured containers waste manufacturing time and materials.
What is needed then is an improved blade that overcomes the shortcomings of conventional solutions.
In summary, an embodiment of the present invention may reduce the pull-back by installing a relief just past the cutting surface. This relief reduces the blade contact surface against the top of the bottle during pull-out of the blade, and presents an angled surface approach to the inner edge of the bottle to reduce any catching as the blade is pulled out.
In an exemplary embodiment, the present invention may be a apparatus for cutting a plastic object, comprising: a blade that comprises a substantially flat base; a sloped wall coupled to and extending at an angle from the base; and a cutter edge coupled to the sloped wall, wherein the base is recessed apart from the cutter edge; and a mount for positioning the blade for cutting the plastic object; wherein the cutter edge is for cutting the plastic object.
In another exemplary embodiment, the present invention may be a blade for cutting a plastic object comprising: a substantially flat base; a sloped wall coupled to and extending away from the base; and a cutter edge coupled to the sloped wall, wherein the base is recessed apart from the cutter edge.
In another exemplary embodiment, the present invention may be a method for cutting a plastic object comprising: providing an apparatus that comprises: a blade that comprises a substantially flat base; a sloped wall coupled to and extending at an angle from the base; and a cutter edge coupled to the sloped wall, wherein the base is recessed apart from the cutter edge; and moving the cutter edge into contact with the plastic object, thereby cutting the plastic object.
Further objectives and advantages, as well as the structure and function of preferred embodiments will become apparent from a consideration of the description, drawings, and examples.
The foregoing and other features and advantages of the invention will be apparent from the following, more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings wherein like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements.
Embodiments of the invention are discussed in detail below. In describing embodiments, specific terminology is employed for the sake of clarity. However, the invention is not intended to be limited to the specific terminology so selected. While specific exemplary embodiments are discussed, it should be understood that this is done for illustration purposes only. A person skilled in the relevant art will recognize that other components and configurations can be used without parting from the spirit and scope of the invention. All references cited herein are incorporated by reference as if each had been individually incorporated.
In an exemplary embodiment, the present invention includes a cutter blade with a reduced cutter edge that touches the finished bottle surface, and a sloped relief in the form of a sloped wall behind the cutter edge to reduce catching during the pull-out of the cutter edge. Cutter blade integrity may be maintained by a tapered back side of the blade to compensate for the relief on the front. In an exemplary embodiment, a conventional mounting configuration may be used to mount the blade, so that no design changes to other machinery are needed to use the cutter blade of the present invention.
As seen in
A separate cutter edge 204a, 204b, 204c, 204d (collectively 204) is coupled to each sloped wall 206a, 206b, 206c, 206d, respectively. The cutter edge 204 may be made of steel. The number of sloped walls and cutter edges is generally defined by the shape of base 202. For example, a six-sided blade may have six sloped walls and six cutter edges. A substantially circular base may have one continuous substantially circular sloped wall around its circumference, with one continuous substantially circular cutter edge. Substantially circular includes oval and elliptical bases.
Each cutter edge 204 is at an angle to the sloped wall 206, and can define a plane substantially parallel to the base 202. This results in the base 202 being recessed apart from the plane defined by the cutter edges 204. The blade 200 may also have a mount 208 for positioning the blade 200 for cutting the plastic object.
In embodiments that are not substantially circular, adjacent cutter edges may be joined together at their sides to form points. In some embodiments, one or more sloped walls may not have a cutter edge.
As a result of the recessed shaped of blade 200, when the cutter edge 204 is moved into contact with the plastic object, thereby cutting the plastic object, the plastic object does not substantially contact the base 202. Therefore, when the blade 200 is moved away from the cut plastic object, no pull-back area is formed.
The blade 200 may be mounted to a conventional cutter assembly, or may otherwise be mounted to be rotated relative to the plastic object.
The embodiments illustrated and discussed in this specification are intended only to teach those skilled in the art the best way known to the inventors to make and use the invention. Nothing in this specification should be considered as limiting the scope of the present invention. All examples presented are representative and non-limiting. The above-described embodiments of the invention may be modified or varied, without departing from the invention, as appreciated by those skilled in the art in light of the above teachings. It is therefore to be understood that, within the scope of the claims and their equivalents, the invention may be practiced otherwise than as specifically described.
