The present invention relates to a hole punch, and more specifically, to a punch for making a plurality of holes in a medium such as paper.
Paper hole punches are common devices found in offices, schools, and homes. Hole punches serve to punch or cut holes into one or more sheets of paper, plastic film, cardboard, etc. The result is that the punched paper or sheet media can then be organized and stored in a binder or fastened within a file.
The working principle of the common hole punch is straightforward. A lever arm is hinged to a base, and one or more punch pins are actuated by the lever arm. When a user presses down on the lever, the cutting ends of the punch pins are advanced through the paper stack and the punched out chads or disk-shaped chips are pushed into a receptacle in the base.
The punch pins and lever are then retracted by the user lifting up on the lever, or by releasing the lever so that a reset spring can return the parts to their respective start positions.
Care should be taken to ensure that the cutting points do not jam from the accumulated chips resulting from repeated hole punching operations that cut through multi-sheet stacks of paper. Improper tearing of the paper or collection of paper perforation chips near or within the peripheral moving parts can cause the punch pins to jam and/or lodge in the paper, thus seizing the hole punch, or at least making the reset step stiff to the user, or diminishing the effectiveness of the reset spring. Moreover, jammed paper chips can easily lead to distortion and damage to hole punch parts, and dulling of the cutting points.
To avoid this problem, scrap collection receptacles have been included in hole punches, as disclosed in, for example, U.S. Pat. No. 7,270,042 (Mori et al.). Such a receptacle or reservoir serves to collect and keep the paper perforation chips away from the cutting points, and consequently reduce the chance of jamming the device due to debris collecting near or within the moving parts.
While the Mori paper punch is one approach of how to avoid device jamming, it suffers from several drawbacks. For example, the apparatus does not take into account that improper tearing in the paper by the punch pin generates undesirable friction or drag on the punch pin, or that the paper shreds can jam the elevating or reset mechanism. If the reset mechanism becomes jammed, there is no way to return the apparatus to its starting state without manually removing the jam and returning the reset mechanism by hand. Since the lever is not directly linked to the reset mechanism or the punch pin, when the handle must be reset by hand in such a paper jam, the device remains inoperable until cleaned.
Given these drawbacks, and more may be apparent to one skilled in the art, there is a need for an improved hole punch that allows a user to safely and effectively return the apparatus to its starting state without manually removing the jam and resetting the elevating unit, and, which will stroke after stroke, cut into a paper stack with repeated reliability such as to reduce the unnecessary tearing of paper or malformed holes which lead to further jamming.
Briefly summarized, the present invention is directed to a manually operated hole punch for punching a hole in a stack of sheet media such as papers, comprising a punch pin frame having a stacked media slot; a lever pivotably mounted to the frame, wherein the lever includes a front portion in front of the pivot and a pressing area behind the pivot; a push rod disposed at the front portion of the lever; a jam release clip having an opening at one end to receive the push rod and an engagement member at the opposite end; a punch pin having cutting points at one end and a base at an opposite end, the punch pin slidably fitted to the frame wherein the cutting points end passes into the stacked media slot and the base is proximate to the push rod, and wherein the engagement member of the jam release clip latches to the punch pin; and wherein pushing at the pressing area pivots the lever in a first direction which drives the push rod into the base end of the punch pin and advances the cutting points end at least partially into the stacked media slot, and lifting up at the pressing area pivots the lever in a second direction which via the jam release clip withdraws the cutting points end at least partially out of the stacked media slot.
It is an advantage of the claimed invention that lifting on the handle retracts the punch pin in the event of a paper jam or when the punch pin gets lodged in the paper stack. It is also an advantage of the claimed invention that the jam release clip eliminates the rotational movement in the punch pin and ensures that the V-notch at the cutting point of the punch pin is held in a specific rotational or angular orientation to the paper stack to be cut, thereby greatly increasing the reliability and efficiency of the paper punching while reducing tearing of the paper, malformed holes or a serrated or uneven lips around the hole, which is unsatisfactory to the user and may also contribute to unnecessary jamming of the device.
These and other objectives of the claimed invention will become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiments that are illustrated in the various drawing figures.
This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. The section titles and overall organization of the present detailed description are for the purpose of convenience only and are not intended to limit the present invention. Accordingly, the invention will be described with respect to a jam release clip for a hole punch. The hole punch can be of a design having a punch pin driven manually by a handle that pivots on a hinge at one end. It is to be understood that the methods and devices described herein is for illustration only. The invention also applies to other methods and devices for hole punch designs having a need for jam release capability.
A preferred embodiment top cover or housing 6 is shown. Housing 6 has a molded-in rib 7 that confines pivot rod 8 on which handle 9 is hinged, and prevents pivot rod 8 from “walking out” or working its way out and disassembling from punch element 2. This allows pivot rod 8 to be made from a single piece without any machining operations to accommodate retaining clips, collars, or pins. In an alternative embodiment, the same part can be used for push rod 10 (to drive the punch pin 3) and pivot rod 8 (which is a hinge for the handle 9), because they may be the same diameter and length. In other words, the identical part can be used as push rod 10 or pivot rod 8. This creates further parts savings. This is possible because of the improvements noted above by use of jam release clips 11 and features of housing 6.
Jam release clip 11 extends at least partially alongside the shaft of punch pin 3 and is assembled to it as shown in
Jam release clip 11 thus replaces a conventional E-clip or collar ring, which would otherwise be needed to hold punch pin reset spring 4 in place. Reset spring 4 provides the force needed to reset handle 9 to its start position as mentioned above. By modifying hole punch 1 to accept the present invention jam release clip 11, the chances for hole punch 1 jamming during normal operation are greatly diminished. The resulting hole punch has a much improved, hitch-free operation as perceived by the user.
Another advantage of the jam release clip 11 is that it holds the rotational orientation of punch pin 3 and prevents significant rotation of punch pin 3 in the assembly. To do this, as seen in
Jam release clip 11 is preferably made from a compliant material (spring steel, plastic, rubber, etc.) so the pair of fingers 14 can be resiliently snapped around the diameter of pin 3 and locked into place. Another flat surface 16 of jam release clip 11 engages a flat surface 17 of the frame of punch element 2, which keeps jam release clip 11 aligned to punch element 2 and therefore pin 3 to punch element 2. This arrangement also has jam release clip 11 at least partially extending alongside of punch pin 3. The fingers 14 still must have a certain degree of strength and rigidity not to flex too much so as to transmit sufficient force to pull the punch pin 3 out from a paper stack if it becomes lodged therein or encounters high friction from sliding inside the hole.
To be sure, an uneven lip at the cutting point 12 generates undesirable friction or drag on punch pin 3. Any tearing action also requires greater user-applied effort at handle 9 since tearing of the paper generates more resistance than normal shearing of the paper from a proper cut. These factors causing increased user effort are avoided in the present invention hole punch by consistent, rotational orientation of cutting points 12 to the paper stack.
Eliminating the rotational movement in punch pin 3 ensures that the V-notch at the cutting point 12 of punch pin 3 is held in a specific rotational or angular orientation to the paper stack to be cut. Once cutting point 12 of punch pin 3 can be oriented consistently, stroke after stroke, then how (i.e., which cutting point edge 12 cuts first, the angle of the punch pin's angle of entry into the paper stack, etc.) cutting points 12 cut into the paper can be predicted so that each stroke cutting into the paper stack can be repeated reliably and efficiently. This improves the consistency of the cuts and minimizes chances of poorly formed holes in the paper. A bad cut may also lead to tearing of the paper instead of shearing of the paper in a proper cut. The tearing in the paper creates a malformed hole or a serrated or uneven lip around the hole, which is unsatisfactory to the user and may create further problems in seizing up the hole punch as described earlier.
As seen in
Again in
In one aspect of the preferred embodiment, jam release clip 11 hooks around and confines the end of push rod 10 (
In an alternative embodiment, jam release clip 11 eliminates compression reset spring 4 on each punch element 2—in the
Punch pin element 2 is essentially a rigid chassis or frame to which is assembled punch pins 3, reset springs 4, pivot pins 8, and other components. Punch pin element 2 (or punch frame) is preferably fairly rigid to resist the structural distorting forces generated when punching through a thick stack of papers, which rigidity ensures ideal alignment of the papers with punch pin cutting points 12 and efficient transmission of forces from handle 9 to punch pin 3. As best seen in
Punch pin element 2 further includes a downward extending alignment tab 24 at the opposite end of element 2 to the L-shaped foot 22. As seen in
Although the present invention has been described in detail with regard to the preferred embodiments and drawings thereof, it should be apparent to those of ordinary skill in the art that various adaptations and modifications of the present invention may be accomplished without departing from the spirit and the scope of the invention. Many modifications and variations are possible in light of the above teaching. Accordingly, it is to be understood that the detailed description and the accompanying drawings as set forth hereinabove are not intended to limit the breadth of the present invention. It is intended that the scope of the invention not be limited by this detailed description, but by the claims and the equivalents to the claims appended hereto.
This is a non-provisional application from which priority is based on provisional application No. 60/975,763, filed Sep. 27, 2007, whose entire contents are hereby incorporated by reference.
Number | Date | Country | |
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60975763 | Sep 2007 | US |