Patent Publication Number: US-6705785-B1

Title: Apparatus for removing perforated side edge guide strips from printer paper

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to tractor feed printers and, in particular, to devices for separating the side edge guide strips on the sides of tractor-fed printer paper from the main body of the paper. 
     2. Description of the Related Art 
     Many printers connected to computers print on a continuous sheet of paper, such as business invoices and the like. The continuous sheet of paper can be separated into individual sheets of paper when desired by tearing the continuous sheet along longitudinally-spaced and transversely-extending lines of perforations. The continuous sheet of paper is fed through the printer by means of side edge guide strips which are formed on opposite sides of the continuous sheet. The side edge guide strips have holes which extend along their lengths at regularly spaced-apart intervals which match the spacing of sprocket teeth on peripheral surfaces of sprocket wheels which are positioned on opposite sides of the printer. The sprocket wheels are driven to provide a tractor feed mechanism for feeding the paper through the printer. 
     The side edge guide strips are usually manually torn from the opposite sides of the individual sheets of paper after the individual sheets are torn from the continuous sheet of paper. This can be a tedious and time-consuming task. Solutions have been proposed in the prior art to perform this task automatically,. For example, U.S. Pat. No. 2,188,347 issued to Fulk discloses a cutting device for cutting strips from the side edge of a continuous paper form using a cutting blade. U.S. Pat. No. 5,102,246 issued to Patz discloses a device for removing the side edges of a paper web which uses a U-shaped housing having a feed slot and a rotating cutting disk mounted within the slot. U.S. Pat. No. 5,120,144 issued to Lund discloses a paper separator that has a tractor feed mechanism that causes a divergence in the paths of the body of the paper form and the side edge strip to cause separation. U.S. Pat. No. 5,259,543 issued to Downing discloses a parting tool for a tractor feed printer that uses a blade intersecting the plane of the paper for shaving the paper along the perforations connecting the guide strip to the sheets of paper. U.S. Pat. No. 5,346,321 issued to Eudy discloses an edge strip trimmer that uses an edge strip hold-down device to remove the edge strips by progressively diverging the plane of the edge strip from the plane of the paper sheet as the paper sheets are fed through the printer. 
     Various other proposed solutions are disclosed by U.S. Pat. No. 5,368,404 issued to Hacker, U.S. Pat. No. 5,505,551 issued to Rutherford, U.S. Pat. No. 5,516,221 issued to Lake, U.S. Pat. No. 5,634,581 issued to Taylor, and Australian Patent No. 241,251 issued to Castleton. All of these prior art solutions tend to be overly complicated and expensive, and many require knife blades, rollers, or other elements requiring maintenance. Thus, there is a need in the industry for an improved device to separate and remove side edge guide strips from printer paper. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a simpler yet highly reliable device to separate and remove the side edge guide strips from computer paper as it leaves the printer. 
     A further object of the present invention is to provide a paper strip removal device that can be installed quickly and easily to existing computer printers. 
     It is a further object of the present invention to provide a paper strip removal device that is economical to manufacture, efficient and reliable in use, capable of a long operating life, and particularly well suited for use with existing tractor-fed printers. 
     To accomplish these and other objects, a paper strip removal device for removing side edge guide strips from tractor-fed computer printer paper is provided by the present invention. The paper strip removal device has first and second plate members rigidly attached together in a spaced apart parallel relationship to one another so as to define a narrow slot therebetween wide enough to receive a marginal side edge portion of a printer paper with its side edge guide strip thereon through the slot. The plate members each have a planar main body portion and a corner portion separated from the main body portion by a narrow slit that extends from a front edge of the plate member toward a rear edge thereof. The corner portions are angled downwardly away from the planar main body portions to create a path for the side edge guide strip that diverges abruptly from a path created by the main body portions for the marginal side edge portion of the printer paper. The diverging paths cause the side edge guide strip to be removed from the marginal side edge portion without using a cutting blade or other moving parts. 
     Numerous other objects and advantages of the present invention will be apparent to those skilled in this art from the following description wherein there is shown and described a preferred embodiment of the present invention, simply by way of illustration of one of the modes best suited to carry out the invention. As will be realized, the invention is capable of other different embodiments, and its several details are capable of modification in various obvious aspects without departing from the invention. Accordingly, the drawings and description should be regarded as illustrative in nature and not restrictive. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more clearly appreciated as the disclosure of the invention is made with reference to the accompanying drawings. In the drawings: 
     FIG. 1 is a perspective view of a printer equipped with a system for removing perforated side edge guide strips from printer paper according to the present invention. 
     FIG. 2 is a perspective view of one of the paper strip removal devices for removing perforated side edge guide strips from printer paper according to the present invention. 
     FIG. 3 is a plan view of the paper strip removal device according to the present invention. 
     FIG. 4 is an outer side view of the paper strip removal device according to the present invention. 
     FIG. 5 is an inner side view of the paper strip removal device according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A device  10  for removing perforated side edge guide strips from printer paper according to the present invention will now be described with reference to FIGS. 1 to  5  of the accompanying drawings. 
     FIG. 1 shows a printer  11  equipped with a pair of strip removal devices  10  attached to each side of a paper outlet  12  of the printer  11  The printer  11  is shown printing on a continuous sheet of paper P, such as business invoices and the like. The continuous sheet of paper P has side edge guide strips S formed on opposite side edges E of the continuous sheet of paper P, which are used to feed the paper P through the printer  11 . The side edge guide strips S have holes  13  at regularly spaced-apart intervals that match the sprocket teeth (not shown) in the printer  11 . 
     The perforated strip removal device  10  of the present invention operates to remove the perforated side edge guide strips S from along the side edges E of the continuous sheet of printer paper P as the paper is discharged from the outlet  12 . The strip removal devices  10  are positioned to direct the removed strips S into a separate waste container T. The perforated strip removal device  10  includes first and second plate members  15  which are generally rectangular in shape, and a means  16  for rigidly, and preferably integrally, attaching the plates  15  to one another. Each of the plates  15  has a pair of opposite faces  17 ,  18 , front and rear edges  19 ,  20 , and a pair of opposite side edges  21 ,  22  extending between and interconnecting the front and rear edges  19 ,  20 . 
     The means  16  for rigidly attaching the plates  15  to one another is a segment  16  that extends only along one side edge  21  of the opposite side edges  21 ,  22  thereof. In the preferred embodiment, the plates  15  are integrally formed of plastic material and a single plate member is folded back on itself to create the segment  16 . The plates  15  are supported in a spaced apart parallel relationship to one another so as to define a narrow slot  23  therebetween wide enough to receive a marginal side edge portion M of a printer sheet P with its perforated side edge guide strip S thereon through the slot  23  with the sheet P extending beyond the rear edges  20  and other side edge  22  of the plates  15 . 
     Each of the plates  15  have a planar main body portion  34  and a front corner portion  25  delineated from the main body portion  34  by a narrow slit  24 . The narrow slit  24  extends between the opposite faces  17 ,  18  of each plate  15 , and runs perpendicularly from the front edge  19  a short distance toward the rear edge  20  thereof. The slits  24  are spaced between the opposite side edges  21 ,  22  thereof so as to define right corner portions  25  on each plate  15  which are aligned with each other. Each front corner portion  25  has a width W 1  between the slit  24  and attached ones of the opposite side edges  21  of the plates  15  which is slightly larger than the width W 2  of the perforated side edge guide strip S on the printer sheet P. When the printer sheet P is moved through the slot  23  between the plates  15 , its perforated side edge guide strip S will move in longitudinal alignment with the front corner portions  25  of the plates  15 , and its marginal side edge portion M will move in longitudinal alignment with corners  26  of the main body portion  34  of the plates  15 , which are separated from the front corner portions  25  by the slits  24 . 
     The front corner portions  25  of the plates  15  are bent downwardly about a bend line  30 , which extends generally perpendicular to the slits  24 . The corner portions  25  are bent about the bend line  30  to diverge from the main body portions  34  at an angle of about 20 to 45 degrees. The corner portions  25  are bent in the same directions from the respective planes of the main body portions  34  of the plates  15  to maintain the slot  23  therebetween. When the marginal side edge portion M of the printer sheet P and its perforated side edge guide strip S are pulled through the slot  23  between the plates  15  their paths will diverge abruptly from one another as a result of the bend line  30  and the narrow slit  24  between the main body portions  34  and the front corner portions  25 . This abrupt divergence of the paths causes a tearing and separation of the perforated side edge guide strip S from the marginal side edge portion M of the printer sheet P along a line of perforations L therebetween. 
     The corner portion  25  of the top plate  15 , as shown in FIGS. 2 to  4 , has an inner edge  35  defined by the slit  24 . The inner edge  35  passes closely across an outer edge of the narrow slot  23  formed between the main body portions  34  of the plates  15  and creates a shearing mechanism to facilitate removal of the side edge guide strips S from the marginal side edge portion M. 
     Peel-off adhesive backing strips  36  can be provided on the lower one of the plates  15  for quick and easy mounting of the device  10 , without the use of tools, to the printer  11 . The device  10  can be fabricated for both left and right-hand mounting on the printer so that the guide strips S can be removed from either or both sides of the printer sheet P, as shown in FIG.  1 . 
     While the invention has been specifically described in connection with specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.