Abstract:
A masking tape tool/dispenser for imparting a lengthwise fold in a length of masking tape. Within the tool, the tape traverses proximate or through a plurality of tape guides for imparting the fold in the tape, such that a first lengthwise region of the adhesive surface is folded against a second lengthwise region of the adhesive surface, leaving sufficient exposed adhesive surface to permit adhesion of the folded tape to a work piece for paint overspray masking. The user can withdraw a continuous length of the folded masking tape from the dispenser, cutting the folded tape when the desired length has been withdrawn. During use, the tool can be hand-held or releasably affixed to a surface.

Description:
[0001]    The present invention claims the benefit of the provisional patent application entitled, Masking Tape Tool/Dispenser, filed on Mar. 6, 2003 and assigned application No. 60/452,624. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to a masking tape dispenser, and more particularly, to a masking tape dispenser that dispenses a length of masking tape wherein a portion of the adhesive surface of the masking tape is folded back onto the adhesive surface.  
         BACKGROUND OF THE INVENTION  
         [0003]    In the auto-body repair and paint industry, masking tape is used in enormous quantities during the process of finishing and painting a vehicle. The tape is used in a variety of different lengths depending upon the surface to be masked. One of the final stages in painting the vehicle, and one very important step, is a careful masking of the vehicle to prevent overspray into unwanted areas during the paint spraying process. For example, the windows, mirrors, tires, door jambs (also referred to as trim edges) and bumpers (if they are not being painted) are masked to prevent the application of paint to those surfaces. It is also desirable to mask the inside surface of the door jambs, the underside of the trunk lid, and any jambs not being painted, such that paint is applied only to the body areas that are exposed when the door or the trunk is closed.  
           [0004]    The use of conventional masking tape to mask these areas prior to spray painting is known. Masking tape comprises an elongated substrate having a first adhesive surface and a second oppositely disposed non-adhesive surface. The adhesive surface easily bonds to most materials, but advantageously can also be easily removed. The tape is supplied in roll form, wherein a length of the tape is wound about a circular roll and dispensed therefrom by grasping the free end and unrolling the desired tape length from the roll.  
           [0005]    When used to demark an area to be painted from an area to remain unpainted, as described above, the masking tape forms an undesirable paint edge as the paint accumulates against a masking tape edge during the spraying process. When the tape is removed, the paint edge is particularly noticeable and is generally considered visually objectionable. To avoid the paint build-up and the attendant paint edge, it is known to fold a portion of an adhesive surface  10  of a masking tape length  12  back onto the adhesive surface  10  to form a folded region  14  as illustrated in FIG. 1. The tape length  12  further comprises a non-adhesive surface  13 .  
           [0006]    As illustrated in FIG. 2, the tape length  12  separates an unpainted region  20  from a painted region  22  of an object  24 . A folded edge  24  of the tape length  12  is positioned facing in a direction of the painted region  22 . As paint is sprayed onto the region  22 , a certain amount of paint accumulates under the folded edge  24 , with more paint accumulating along an outward edge  30  and less paint accumulating along an inner region  32 . See FIG. 1. As a result, the paint is tapered or feathered from the painted region  22  to the unpainted region  20 , eliminating the objectionable paint edge. This technique is typically utilized in an automotive door and trunk lid jamb, as well as fender and quarter panel jambs, to present a gradually tapering region between the painted outside surface and the unpainted inside jamb surface. When folded tape is used, the paint repair is not noticeable and the vehicle appears to have its original factory paint job.  
           [0007]    Although the results according to the aforedescribed method are desired, forming the masking tape into the configuration illustrated in FIG. 1 is not trivial. The painter must grasp a length of tape in one hand, fold a section of the adhesive surface back onto the adhesive surface and position his fingers of one hand appropriately to continue folding the tape as he pulls additional tape from the roll with his other hand. As the painter pulls the tape, he must exercise caution to ensure that the tape does not become tangled with itself nor dragged along the floor, as such may affect the adhesive properties of the tape and cause failure of the tape to adhere to the surface to be painted. This manual folding process restricts the length of tape that can be folded in one continuous tape length, requiring the painter to serially piece folded tape lengths to form the boundary between the painted and unpainted regions. Forming the tape using this folding action is time consuming and requires much patience, practice and dexterity. This manual method is not easily learned and in fact many automotive body repair technicians are incapable of folding the tape according to this technique. Although it is possible to fold a length of tape by laying the tape on a surface with the adhesive side up, grasping and folding a portion of the adhesive surface back onto itself, this techniques is impractical, given the large quantity of making tape and the long lengths used in the automotive painting business.  
         SUMMARY OF THE INVENTION  
         [0008]    The present invention comprises, in one embodiment, a dispenser for forming a lengthwise fold along a tape edge, wherein the fold comprises a first lengthwise region of an adhesive surface folded against a second lengthwise region of the adhesive surface as the tape is withdrawn from a tape roll and traverses a tape path. The dispenser comprises a base and a rotatable hub oriented substantially horizontal to the base for receiving and supporting the tape roll, wherein the tape is withdrawn from the roll in a substantially vertical orientation relative to the base. A plurality of intermediate tape guides supported by the base plate and disposed along the tape path impart a curvature along a top tape edge as the tape traverses the tape path. A folding tape guide is disposed in the tape path following the plurality of intermediate tape guides. The folding tape guide comprises an open frame having first and second edges substantially parallel to the tape path and third and fourth edges substantially perpendicular to the tape path, wherein the first and second edges define a first channel therebetween. The folding tape guide further comprises a first tab extending from the first edge in a direction toward the second edge, and further comprises a second tab extending from the first tab to the second edge. An upper surface of the second tab is below an upper surface of the first tab. The tape path further comprises a path under the third edge into the first channel, above the first and the second tabs and under the fourth edge, and wherein a user draws the tape upwardly upon exiting the folding tape guide to form the fold.  
           [0009]    The invention further comprises a method for folding tape having two parallel edges defining a tape width therebetween and comprising an adhesive surface and a non-adhesive surface, wherein a first portion of the adhesive surface extends from one tape edge is folded onto a second portion of the adhesive surface. A first step curves the first portion of the adhesive surface in a direction toward the adhesive surface. The tape is inserted into a tape guide comprising an open rectangular frame further comprising first and second members parallel to the tape edges and third and fourth cross members connected to the first and second members. The first and the second members define a channel therebetween having a width substantially equal to the tape width and further defining a notch within the channel. The tape is inserted under the first cross member and extends into the channel. The tape is drawn through the tape guide and under the second cross member, wherein the notch urges the curved edge onto the second portion of the adhesive surface to fold the tape edge. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The foregoing and other features of the invention will be apparent from the following more particular description of the invention, as illustrated in the accompanying drawings, in which like reference characters refer to the same parts throughout the different figures. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.  
         [0011]    [0011]FIG. 1 illustrates a folded section of masking tape;  
         [0012]    [0012]FIG. 2 illustrates a spray painting application for the folded section of masking tape shown in FIG. 1;  
         [0013]    [0013]FIG. 3 is a perspective view of the masking tape dispenser according to one embodiment of the present invention;  
         [0014]    [0014]FIG. 4 is a top view of one embodiment of the masking tape dispenser of the present invention;  
         [0015]    [0015]FIGS. 5 through 7 illustrate the successive folding stages as the tape passes through guides of the masking tape dispenser;  
         [0016]    [0016]FIG. 8 is a partial cross-sectional view taken along a plane through FIG. 7;  
         [0017]    [0017]FIG. 9 illustrates a perspective view of a masking tape dispenser according to another embodiment of the present invention; and  
         [0018]    [0018]FIG. 10 is a close-up view of the tape of FIG. 9 during one stage of the folding process. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]    Before describing in detail the particular method and apparatus for forming a folded section of masking tape according to the present invention, it should be observed that the invention resides in a novel and non-obvious combination of elements and process steps. So as not to obscure the disclosure with details that will be readily apparent to those skilled in the art, certain conventional elements and steps have been presented with lesser detail, while the drawings and the specification describe in greater detail other elements and steps pertinent to understanding the invention.  
         [0020]    The present invention folds a length of masking tape for use in masking a painted region  22  from an unpainted region  20 , preventing a heavy edge or build-up of paint between the painted region  22  and the unpainted region  20  as illustrated above in FIG. 2. Such a folded length of tape (including tapes other than masking tape) may have a useful function for purposes other than masking between painted and unpainted regions. After installing a masking tape roll in a dispenser of the present invention, the user grasps the masking tape free end and pulls, with a minimal amount of force, the tape from the roll and through the dispenser, form a fold along one tape edge. For masking tape having a ¾″ width, a folded region of approximately ¼″ is formed. A cutter attached at an exit end of the tool allows the user to tear off a desired length of the folded masking tape. The tool is manually operated with no requirement for an electrical supply.  
         [0021]    The presented figures illustrate elements of the masking tape dispenser, showing in particular a tape length as it passes through the various guides of the dispenser and is formed into the desired folded configuration.  
         [0022]    As shown in FIG. 3, a masking tape dispenser  40  (also referred to a masking tape tool) comprises a base  42  to which are affixed intermediate guides  44 ,  46 ,  48  and a folding tape guide  50 . The base  42  and the guides  44 ,  46 ,  48  and  50  can be formed from various known materials, including Plexiglas®, fiberglass, other plastic materials, and metal materials and alloys. The intermediate guides  44 ,  46 ,  48  and a folding tape guide  50  can be affixed to the base  42  using conventional fasteners such as screws, bolts and nuts or an adhesive material, or by using other techniques and elements known in the art. In another embodiment, the base  42  and the guides  44 ,  46 ,  48  and  50  can be formed as a unitary structure, for example, by a mold process.  
         [0023]    In one embodiment, legs  60 ,  61  and  62  extending from a bottom surface of the base  42  further comprise suction cups  64  for releasably attaching the dispenser  40  to a work surface, such as a floor or flat clean surface proximate the vehicle being painted. Other attachment techniques can also be used and are considered within the scope of the invention. The user can also hold the tape dispenser  40  in one hand while pulling the folded tape from an exit end with the other hand. The suction cups  64  can be removed and the masking tape dispenser  40  removably attached to a workbench or another work surface.  
         [0024]    A tape roll  65  comprising an elongated length of tape  66  wound about the roll  65  (for example, masking tape having a width of about ¾″) is frictionally engaged over a hub or spool  68 . The hub  68  is made to rotate in a clockwise direction about an axis  70  as the tape length  66  is withdrawn from the roll  65 . A free end  72  withdrawn from the roll  65  is directed toward a guide  44 , with the adhesive surface  10  facing a direction indicated by an arrowhead  74 .  
         [0025]    [0025]FIG. 4 is a top view of the base  42 , generally indicating a tape path  80  through which the length of tape  66  passes proximate the guides  44 ,  46 ,  48  and  50 . The guide  44  generally directs the tape  66  toward the guide  46 . As the tape  66  exits the guide  46 , the tape is beginning to curve in the direction  74 . This curve is illustrated in FIG. 5, which also identifies a bottom edge  86  and a top edge  87  of the tape length  66 . Generally, the guides  46  and  48  transition the tape orientation from a substantially vertical orientation as the tape  66  is fed from the roll  65 , to a substantially horizontal orientation prior to entering the tape guide  50 .  
         [0026]    The guide  46  comprises a generally L-shaped structure (see FIG. 5) further comprising a base segment  90 , a vertical segment  92  and a tab  94 , which define a notch  96 . As the tape length  66  is drawn through the guide  46 , the tab  94  and the notch  96  force the tape to curve in the direction  74 , causing the tape length  66  to begin to fold as a region  100  is folded in a direction of a region  102 . Both regions  100  and  102  are on the adhesive side  10  of the tape length  66 . Generally, a notch length is selected to impart the curve in the tape length  66 , such that as the tape length  66  passes into the notch  96 , the tape strikes the tab  94  causing the tape to curve as shown.  
         [0027]    As shown in FIGS. 4 and 6, the tape fold becomes more pronounced as the tape passes the guide  48 , which comprises a face  106  having an upper region  108  extending beyond (in a direction toward the tape  66 ) a lower region  110 .  
         [0028]    The tape  66  continues to curve along its length (i.e., lengthwise) as it enters the guide  50 , passing under a member  130  (see FIG. 7) into a channel region  132  defined by two spaced-apart and substantially parallel members  134  and  136 . A tab  140  and a tab  142  are disposed within the channel  132  and between the members  134  and  136 . A top surface of the tab  140  is disposed above a top surface of the tab  142 , such that the tab  140 , the tab  142  and the member  136  form a notch  150 . See the partial cross-sectional view of FIG. 8, taken along plane  8 - 8  of FIG. 7. As the tape  66  passes through the channel  132  and a tape region  155  passes through the channel  150 , the region  155  continues to fold toward the adhesive surface  10 , due to the force imparted along the tape width by the tab  140  and the tab  142 . The unfolded portion of the tape  66  passes over the tab  140  and the folded portion passes through the notch  150 .  
         [0029]    To complete the tape folding process, the user applies an upwardly directed force to the tape  66  as it passes under a member  156  and exits the guide  50 . According to one embodiment, a distance between the base  42  and the member  130  is greater than a distance between the base  42  and the member  156  (i.e., the guide  50  is inclined downwardly in the direction of the tape path). The tape  66  is now in the configuration of FIG. 1, wherein the region  155  is folded against the adhesive surface  10  to form the folded region  14  as illustrated in FIG. 1. As the tape  66  exits the guide  50 , the non-adhesive surface  13  is facing upward and the adhesive surface  10  is facing down.  
         [0030]    The desired length of tape is cut from the roll  65  when the user urges the tape  66  against a cutting device  160  that is shown in FIG. 3. In one embodiment, the cutting device comprises a serrated edge  162 .  
         [0031]    In one embodiment the tape dispenser  40  accommodates masking tape having a width of about ¾.″ In such an embodiment the width of the channel  132  is approximately equal to the tape width. In this embodiment, the folded region  14  comprises a width of about ¼,″ leaving about ½″ of the adhesive surface  13  to be applied to the desired surface for masking prior to painting. In a preferred embodiment, the width of the notch  150  is approximately equal to the width of the folded region  155  of the tape.  
         [0032]    To load the tape dispenser  40 , the tape roll  65  is loaded on the hub  68  and the length of tape  66  is withdrawn in a clockwise direction from the roll  65 . The tape length  66  is then extended about one inch beyond the end of the base  42 . A short section across a width of the tape at a free end of the tape length  66  is folded back against the adhesive surface  10 . With the non-adhesive surface  13  facing upward, the end of the tape  66  is threaded under the member  130 , into the channel  132  and under the member  156 . The remaining length of tape  66  is positioned proximate the guide  44 , within the notch  96  of the guide  46  and proximate the face  106  of the guide  48 . The length of tape is now folded as described above as the user exerts an upwardly directed force on the tape  66  exiting the guide  50 .  
         [0033]    [0033]FIG. 9 illustrates another embodiment of the present invention wherein the tape roll  65  is oriented vertically with respect to the base  42 . The hub  68  is rotatably affixed to two supports  200  and  202  for supporting the roll  65  in the position as illustrated. The tape  66  is withdrawn from the roll  65  in a substantially horizontal orientation relative to the base  42 . A guide  204  comprises a vertical member  206  affixed to the base  42 , a horizontal member  208  connected to the vertical member  206  and a tab  210  connected to the horizontal member  208 . The vertical member  206 , the horizontal member  208  and the tab  210  define a notch  212  for receiving the tape  66 . A notch length is less than a tape width, causing the tape to curve downwardly as it passes through the notch  212 . See FIG. 10. The tape  66  then enters the guide  50  for completing the folding process as described above.  
         [0034]    As described above, using masking tape processed through the masking tape dispenser  40  eliminates heavy paint build-up in the door jambs/trim edges. The invention can also be advantageously employed for a two tone or two color paint job. When painting a two-tone color scheme, the two regions are masked, creating a heavy paint build up or crease between the two color regions. Use of the folded tape formed according to the teachings of the present invention, allows the paint to be applied such that the crease is replaced with a misty or feathered edge. With the crease absent, pinstripes can be easily applied over the area where the two colors join, leaving a factory finish.  
         [0035]    The invention can also be utilized during the process of applying road guard/chip guard to a bottom vehicular surface. During the process of applying the material, the painter is faced with the obvious build-up of the sprayed material. By using the invention to form the folded tape for masking, the painter eliminates a jagged edge that is caused due to the road guard/chip guard being excessively thick at the sprayed edge.  
         [0036]    An apparatus and method useful for forming a folded length of masking tape has been described. Specific applications and exemplary embodiments of the invention have been illustrated and discussed, providing a basis for practicing the invention in a variety of ways and in a variety of embodiments. Numerous variations are possible within the scope of the invention. Features and elements associated with one or more of the described embodiments are not to be construed as required elements for all embodiments. The invention is limited only by the claims that follow.