The present application is directed to a method and apparatus for providing rotational force upon objects accessible via an opening having an inner diameter.
Rolled material supplied on full length spools or, optionally, on one or more spool ends typically require a core, a spool, or spool ends, formed for fitting on a complementary shaped rotating drive device such as providing a notch in the core for engaging a surface feature of the drive device, often referred to as a notch and key design. These are easy to use but can be expensive. Other methods include using a flange with both keys and straight ribs to transmit torque. These are difficult to use due to the force required to insert the flanges into the core. Roll fed printers that use cardboard cores for supplying wound media are an example. The cardboard core defines an inner diameter opening having a soft material core. Prior art approaches in this regard have relied on frictional engagement between a rotational drive means to transmit torque to the core/roll. This would require a certain amount of force to insert and remove the rolled media. Reduction of the insertion force has been achieved in other prior art by means of a spring loaded expansion of the roll after insertion. Other prior art methods involve blades fastened to a tube which is inserted into a media roll and engage the core at points near the middle of the length of the roll which also requires some manual effort to insert.
Roll fed printers that use cardboard cores for supplying wound media are an example application of the means and methods of the present invention. The present invention does not rely on friction to transmit torque to the roll, thereby providing a more positive drive than frictional engagement, does not penetrate the core to any significant distance, and is simpler in construction.
This can eliminate the need for a notched core for a roll of paper, for example. The notch feature can add significant expense to the core. The angle of the rib (blade) in the present invention allows for easy insertion and removal of the flanges into the core as opposed to other designs which require considerable force. By the use of angled ribs on the drive flange which penetrate into a soft core, such as cardboard, to transmit torque to the core. Media manufacturing cost is reduced due to elimination of core notching.
A preferred embodiment of the present invention comprises an apparatus including a flange having a post extending orthogonally therefrom and a blade extending from the post to the flange. The post comprises a circular cross-section as does a core of a spool that is designed to be positioned on the post. The blade comprises a length of about 6.4 mm, a width of about 0.4 mm, and a height of about 0.5 mm. When the post is disposed in the core the blade penetrates the core inside diameter and a flange of the apparatus abuts the core. Preferably, a height of the blade is less than a thickness of the core.
Another preferred embodiment of the present invention comprises a spool end including a post for receiving a roll wherein the post includes a rib configured to penetrate an inside diameter surface of the roll when the roll is received and to remain in a penetrated state so long as the roll remains on the post. The rib extends from the post to a flange portion of the spool end. A cutting edge of the blade angles away from the post as the blade extends toward the flange. A cutting edge of the blade is coincident with a line that intersects a rotational axis of the spool end. The blade is configured to apply a rotational force upon the roll when the spool end is rotated. The blade is also configured to prevent the roll from rotating when the spool end is held in a fixed position. The roll comprises two ends and the blade is configured to remain in the penetrated state at one of the ends of the roll.
Another preferred embodiment of the present invention comprises a post for receiving one end of a hollow core wherein the hollow core has a sheet of material wound thereon. A blade disposed on the post penetrates and remains in an end of the hollow core when the hollow core is positioned over the post for controlling a rotation of the hollow core. The blade is disposed on the post at an angle such that the blade penetrates in a radial direction further into the hollow core as the hollow core moves over the post during insertion. A flange disposed on the post abuts the end of the hollow core when the hollow core is positioned over the post.
These, and other, aspects and objects of the present invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating preferred embodiments of the present invention and numerous specific details thereof, is given by way of illustration and not of limitation. For example, the summary descriptions above are not meant to describe individual separate embodiments whose elements are not interchangeable. In fact, many of the elements described as related to a particular embodiment can be used together with, and possibly interchanged with, elements of other described embodiments. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. The figures below are intended to be drawn neither to any precise scale with respect to relative size, angular relationship, or relative position, nor to any combinational relationship with respect to interchangeability, substitution, or representation of an actual implementation.
Without limiting any dimensions in any manner whatsoever the elements shown in the Figures, the following are examples of the dimensions of preferred embodiments of the present invention as tested and designed by the inventors of the present invention, referring generally to
The Core ID was tested using a prototype of 3.009 inches with tolerance +/−0.008 inches. The mating post diameter was made at 2.995 inches with tolerance of +/−0.005 inches. Max core ID was determined to be 3.017 inches with materials available and Min flange OD was determined to be 2.990 inches with materials on hand. If the blade height is 0.020, the effective minimum flange OD is 3.030 to 3.040 inches, with resulting dimensions as follows:
minimum blade engagement=(3.030−3.017)/2=0.013/2=0.0065″
maximum blade engagement=(3.04−3.001)/2=0.039/2=0.0195″
The length and height of the blade can vary but should form an angle 104 of approximately 4 to 5 degrees with the axis of rotation 109 of the spool to minimize insertion force. Thus, in the above example of a blade height of 0.020″, the length of the rib 106 would be approximately 0.25″.
The thickness of the rib 107 should be kept to a minimum to minimize insertion force but will depend on the rib material strength, hardness of the core it is being inserted into, and the torque transmitted per rib. A typical thickness would be 0.016″ to 0.020″ for use with a cardboard core.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.
Reference is made to commonly assigned, co-pending U.S. patent application Ser. No. ______ by Richard S. Paoletti. (Docket K000392) filed of even date herewith entitled “Notchless Core”, the disclosure of which is incorporated herein by reference in its entirety.