TAPE APPLICATOR AND METHOD OF USING

BACKGROUND

An adhesive tape is often applied to various surfaces for masking purposes, such as on automotive body panels where a two-tone paint scheme is desired. Often, a tape applicator is used to hold an adhesive tape spool and feed the adhesive tape to the surface on which the adhesive tape is to be applied.

SUMMARY

Conventional adhesive tape applicators fail to apply adhesive tape effectively when applying the tape in an arc or along a curve on the automobile. Only vary large sweeping arcs might be accommodated and the tools are generally only effective to apply the tape in straight lines. As such, when tighter curves and turns are necessary for masking off the paint job, the mechanical tape applicators are abandoned, and skilled operators apply the tape by hand much like how pin stripping is applied to a car by hand. This requires a great deal of operator skill and time to accomplish.

In the automotive industry low adhesive peel strength and high elastic elongation adhesive tapes are used for two-tone paint masking where easy removal from the automobile is necessary to not damage the underlying base paint layer. For adhesive tapes having a machine direction (MD) elongation at yield strength greater than 250, 500 or even 1000 percent MD elongation, conventional mechanical tape applicators are unable to apply the tape in the curved lines necessary for some two-tone paint schemes used on modern automobiles.

In order to apply an adhesive tape as a curve or arc, the outer edge of the tape having a larger radius of curvature must be stretched (elongated) relative to the inner edge of the tape having a smaller radius of curvature or the adhesive tape will crinkle and not lay flat. This is because the tape's outer edge in the curve is physically longer (greater radius and thus longer arc circumference) than the tape's inner edge in the curve. The wider the tape's width, the greater the inner and outer edge length difference is. If the tape is not stretched as it is applied, the inner edge of the tape in the curve will crinkle and bunch up since too much tape length is present compared to the outer edge. By stretching the tape just enough, the inner edge can be made to lie flat while the outer edge is stretched longer than the inner edge and also lie flat. Thus, when applying tape by hand, skilled operators know how much to stretch the tape as various radius curves are encountered and then to relax the stretch when applying the tape in a straight line. The tighter the curve, the more the tape stretch is needed just prior to applying the tape to the surface.

The high elongation tapes supplied to the automotive industry can handle the stretch requirements to follow a curvilinear line, but conventional mechanical tape applicators have no means of temporarily stretching the tape when negotiating the curve and then not stretching the tape as much when applying it in a straight line like a skilled operator can. Hence, there is a need for a mechanical tape applicator that can apply the adhesive tape along a curvilinear line for a two-tone paint job to speed up manufacturing operations on the painting line in an automotive plant.

The inventors have determined that by placing an intermittent adhesive tape braking assembly between the unwind and the tape applicator head in a tape applicator, the brake assembly can be actuated when needed and released when not needed. This temporally stretches the adhesive tape in a tape span between the brake assembly and the tape applicator head thereby allowing the tape to be applied in an arc or curve without crinkling. Once the curve has been negotiated, the brake assembly can be released and no longer apply any additional tension to the tape as it traverses from the unwind to the tape applicator head for straight line tape application. By modulating the brake pressure, a tighter or a shallower curve can be easily accommodated.

Hence in one embodiment, the invention resides in a tape applicator including: an adhesive tape spool unwind; an adhesive tape path from the adhesive tape spool unwind to a tape applicator head; an intermittent brake assembly located between the adhesive tape spool unwind and the tape applicator head for selectively applying a braking force to an adhesive tape traversing the adhesive tape path; and a tape span between the intermittent brake assembly and the applicator head for adhesive tape elongation.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments disclosed herein may be more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numerals used in the figures refer to like components.

FIG. 1 is a perspective view of a tape applicator and a work surface, according to an embodiment of the present disclosure. 30

FIG. 2 is a perspective view of the tape applicator without the work surface.

FIG. 3 is a perspective view of an intermittent brake assembly portion of the tape applicator.

FIG. 4 illustrates a cutting head, a cutting blade, and the intermittent brake assembly of the tape applicator.

FIG. 5 illustrates a cut away view of the cutting head, the cutting blade, and the intermittent brake assembly of the tape applicator.

FIG. 6 illustrates an exploded view of the intermittent brake assembly.

FIG. 7 illustrates the geometry of the cutting blade of the tape applicator.

FIG. 8 is a flowchart for a method of using the tape applicator for applying the adhesive tape to the work surface.

DETAILED DESCRIPTION

In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

Throughout this document, values expressed in a range format should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a range of “about 0.1% to about 5%” or “about 0.1% to 5%” should be interpreted to include not just about 0.1% to about 5%, but also the individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%) within the indicated range. The statement “about X to Y” has the same meaning as “about X to about Y,” unless indicated otherwise. Likewise, the statement “about X, Y, or about Z” has the same meaning as “about X, about Y, or about Z,” unless indicated otherwise.

In this document, the terms “a,” “an,” or “the” are used to include one or more than one unless the context clearly dictates otherwise. The term “or” is used to refer to a nonexclusive “or” unless otherwise indicated. The statement “at least one of A and B” or “at least one of A or B” has the same meaning as “A, B, or A and B.” In addition, it is to be understood that the phraseology or terminology employed herein, and not otherwise defined, is for the purpose of description only and not of limitation. Any use of section headings is intended to aid reading of the document and is not to be interpreted as limiting; information that is relevant to a section heading may occur within or outside of that particular section.

The term “about” as used herein can allow for a degree of variability in a value or range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated limit of a range, and includes the exact stated value or range.

The term “substantially” as used herein refers to a majority of, or mostly, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or 100%. The term “substantially free of” as used herein can mean having none or having a trivial amount of, such that the amount of material present does not affect the material properties of the composition including the material, such that the composition is about 0 wt % to about 5 wt % of the material, or about 0 wt % to about 1 wt %, or about 5 wt % or less, or less than or equal to about 4.5 wt %, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.01, or about 0.001 wt % or less.

The present disclosure relates to a hand-held tape applicator 100 for an adhesive tape 102. As illustrated in FIGS. 1 and 2, the tape applicator 100 is used to apply the adhesive tape 102 on a work surface 104. For example, the work surface 104 may include an automotive part, such as a frame of a vehicle. The adhesive tape 102 may be applied to the work surface 104 where a two-tone paint scheme is desired. As illustrated, the work surface 104 includes a first surface 106 and a second surface 108 that is angularly disposed relative to the first surface 106. In the illustrated example, the first and second surfaces 106, 108 are substantially perpendicular to each other. Further, the tape applicator 100 includes the adhesive tape 102. More particularly, the tape applicator 100 includes an adhesive tape spool 110 having the adhesive tape 102 wound around a generally circular support or core. The adhesive tape 102 includes an adhesive side 112 that contacts the work surface 104 and a non-adhesive side 114 opposite to the adhesive side 112. In the illustrated example, the adhesive tape 102 is being applied on the first surface 106 of the work surface 104. The second surface 108 may follow a curvilinear path requiring the adhesive tape's edge to follow the same curvilinear path,

Referring to FIGS. 2 and 3, the tape applicator 100 includes a tape applicator head 116. The tape applicator 100 includes a frame 118 and a handle 120 coupled to the frame 118. The frame 118 is embodied as a plate that supports various components of the tape applicator 100 and may be made of a material, such as aluminum. The tape applicator 100 includes an adhesive tape spool unwind 122 for dispensing the adhesive tape 102. The adhesive tape spool 110 is coupled to the adhesive tape spool unwind 122. The adhesive tape spool unwind 122 is rotatably coupled to the frame 118 by a bolt. The adhesive tape spool unwind 122 includes conventional features such as a hub 123 for mounting the adhesive tape spool 122 by its core and a clamping arrangement 125 for retaining the adhesive tape spool 110 to the hub 123. The adhesive tape spool unwind 122 is rotatable relative to the frame 118 for dispensing the adhesive tape 102 supplied as a spool of adhesive tape wound on a core. The adhesive tape spool unwind 122 facilitates easy and quick dispensing of the adhesive tape 102. In some examples, the adhesive tape spool unwind 122 may include a fixed brake assembly that restricts undesirable spinning of the adhesive tape spool 110. The fixed brake assembly operates as a constant drag brake and is used to apply a constant, unchanging drag force to the adhesive tape spool 110. Typically, a screw and friction washers are used to retard free spinning of the hub 123. By tightening the screw more, the harder it is to turn the hub 123.

The tape applicator 100 has a handle block 120 that houses a pinching head 184 for use in cutting the adhesive tape and a brake assembly 121 for tensioning and elongating the adhesive tape 102 when applying it in a curvilinear line. The handle block 120 has an integral handle 124 extending from it. The handle 124 has a cylindrical shape. The handle block 120 is coupled to the frame 118 by a bolt. In one example, the handle 120 is hollow and has a threaded insert such that a through bolt through the frame 118 can secure the handle block 120. In other examples, the handle 120 may be integral with the frame 118. In the illustrated example, the tape applicator 100 includes only one handle 124 to grasp and guide the tape applicator 100 along the work surface 104. In other examples, the tape applicator 100 may include more than one handle coupled to the frame 118. In such examples, the handles may be bolted to opposing sides of the frame 118 forming a generally “V-shaped” structure for grasping with both hands. It should be noted that the design of the handle 124 described herein is exemplary, and the handle 124 may include any other shape or design generally known in the art.

The tape applicator 100 also includes a tape guide wheel 130 disposed between the unwind 122 and the tape applicator head 116 for directing the adhesive tape 102 along an adhesive tape path 132 from the unwind 122 to the work surface 104. The adhesive tape path 132 includes all the elements needed after the adhesive tape leaves the adhesive tape spool 110 to guide the adhesive tape 102 from the unwind 122 to the work surface 104.

A cutting section 131 includes a cutting head 156, a cutting blade 160, and a pinching head 184. The tape guide wheel 130 is rotatably disposed in the adhesive tape path 132 for receiving the adhesive tape 102. The cutting section 131 is located prior to the tape guide wheel 130 in the direction of adhesive tape travel but it can also bel located after. The adhesive tape 102 leaves the adhesive tape spool unwind 122 from the adhesive tape spool 110 with the adhesive side 112 facing the cutting blade 160 and the non-adhesive side 114 facing the brake assembly 121. As such, the adhesive side 112 touches the circumference of the tape guide wheel 130. To minimize stickiness of the adhesive tape 102 on the tape guide wheel 130 as the adhesive tape moves through the tape applicator 100, the tape guide wheel may be optionally grooved as shown. Grooving the tape guide wheel 130 reduces the contact area between the tape's adhesive side 112 and the tape guide wheel helping to reduce the force needed to pull the adhesive tape 102 along the adhesive tape path.

The tape guide wheel 130 retains and moves the adhesive tape 102 in the adhesive tape path 132 irrespective of a diameter of the adhesive tape spool 110 in the unwind 122, as the diameter of the adhesive tape spool 110 changes during use and pulls the adhesive tape 102 between the cutting head 154 and the push button actuated pinching head 184 for severing with the cutting blade 160. The tape guide wheel 130 is coupled to the frame 118. In an example, the tape guide wheel 130 may be bolted to a threaded hole in the frame 118. In another example, the tape guide wheel 130 may be integral with the frame 118. The tape guide wheel 130 is embodied as a generally tubular member having a number of external grooves extending along a length of the tape guide wheel 130. The tape guide wheel 130 can be made from a machined ultra-high molecular weight polyethylene.

The tape applicator head 116 is the mechanical element that pushes the tape's adhesive side 112 into engagement with the work surface 104. It can be as simple as a pressure pad or brush or include additional elements to guide and orient the adhesive tape 102 onto the work surface 104. In one embodiment, the tape applicator head 116 can include an optional turning board 134 located after the guide wheel 130. The turning board 134 is disposed in the adhesive tape path 132, such that the turning board 134 changes the direction of travel in the adhesive tape path 132 by 90 degrees and positions the tape's adhesive side 112 to face the work surface 104.

The turning board 134 is an integrally molded part of the tape applicator head 116 that is coupled to the frame 118 with a fastener. The turning board 134 has a rounded turning surface 138 the non-adhesive side 114 of the tape runs on for less drag and less adhesive tape 102 damage. In an example, the rounded turning surface 138 is angled at approximately 45 degrees relative to the tape's travel direction prior to the rounded turning surface 138. In the illustrated example, the turning board 134 changes the direction of the adhesive tape 102 by approximately 90 degrees. In other examples, the turning board 134 may change the direction of the adhesive tape 102 by any other angle, as per requirements.

The turning board 134 also includes an optional guide channel 140 that is generally U-shaped with a flat bottom and vertical sides. Alternatively, the guide channel 140 may only have one upstanding vertical side that is used to guide the tape instead of two. Typically, the inner edge in such a configuration would be supplied. Often in such a configuration the rounded turning surface 138 is adjusted to be at approximately a 45.25 degree angle to ensure the adhesive tape is biased to the inner edge with the upstanding vertical side. The choice of one or two sides and turning surface angle is often a consider of if the tape dispenser is designed to work with primarily one adhesive tape width or widely varying adhesive tape widths. When the width of the adhesive tape varies significantly, the 45.25 degree angle may be used to ensure the tape does not excessively wander in the guide channel 140. In that instance, the other upstanding wall may be eliminated to allow significantly wider adhesive tapes and narrower adhesive tapes to be used on the same tape dispenser.

The guide channel 140 helps to ensure the adhesive tape does not skate off the turning board 134 prior to engaging with the rounded turning surface 138. The width of the guide channel 140 is selected to provide a slight clearance for the width of the adhesive tape 102 but not so much that the adhesive tape can wander excessively within the guide channel.

The tape applicator 100 can include an optional magnet 144 coupled to the turning board 134. In the illustrated embodiment, the tape applicator 100 includes one magnet 144, however, the tape applicator 100 may include two or more magnets 144. The magnet 144 facilitates attraction of the tape applicator 100 towards a guiding surface 142 (see FIG. 1) of the work surface 104.

The tape applicator 100 includes a pair of guide rollers 146 coupled to the turning board 134. The guide rollers 146 contact the guiding surface 142 when the tape applicator 100 is positioned on the work surface 104 (see FIG. 1). More particularly, the pair of guide rollers 146 roll on the guiding surface 142 that is angularly disposed relative to the first surface 106 of the work surface 104 onto which the adhesive tape 102 is applied. The guide rollers 146 ensure that the tape applicator head 116 tracks the edge of the work surface where first surface 106 meets second surface 108. The guide rollers 146 and the magnet 144 are coupled to an upper plate 148 that is coupled to the turning board 134. By adjusting the distance between an outer circumference of the guide rollers 146 and the adhesive tape's edge, the amount of offset for the adhesive tape relative to the guiding surface 142 can be controlled.

Further, the turning board 134 also includes a pressure pad. The pressure pad contacts the non-adhesive side 114 of the adhesive tape 102 when applying the adhesive tape 102 to the work surface 104. The pressure pad applies a force on the adhesive tape 102 thereby helping to secure the adhesive tape 102 to the work surface 104. The pressure pad may also assist with smoothing out possible wrinkles and/or air bubbles depending on a width of the adhesive tape 102. The pressure pad is generally embodied as a rectangular shaped pad that may be adhesively disposed into a square recess on the underneath side of the turning board 134 below the magnet 144. The pressure pad will generally extend slightly above the surface to which it is applied and push on the tape's non-adhesive side 114 pressing it into the work surface 104. Alternatively, the pressure pad 155 may have any other shape. A material of the pressure pad 155 may include elastomeric materials, foam materials, bristle brushes, and the like, without any limitations.

Referring now to FIG. 7, the tape applicator 100 includes the cutting head 156. The cutting head 156 is disposed proximate the tape guide wheel 130 (see FIG. 4) in the adhesive tape path 132. Specifically, the cutting head 156 is disposed between the tape guide wheel 130 and the adhesive tape spool unwind 122 in the adhesive tape path 132. The cutting head 156 faces the adhesive side 112 of the adhesive tape 102. The cutting head 156 includes a base surface 158 and the cutting blade 160 extending from the base surface 158.

The cutting head 156 also includes a first portion 162 and a second portion 164. Each of the first and second portions 162, 164 extend from the base surface 158. Further, the base surface 158, the first portion 162, and the second portion 164 together define a recess 163. The cutting blade 160 is partially received within the recess 163. More particularly, a portion of the cutting blade 160 that projects upwards from the base surface 158 is disposed within the recess 163. The first portion 162 defines a first contact surface 165 and the second portion 164 defines a second 30) contact surface 167. The first and second contact surfaces 165, 167 may contact the adhesive side 112 of the adhesive tape 102 during the cutting of the adhesive tape 102 to increase a tension on the adhesive tape 102. Further, when the adhesive tape 102 is being applied, the first and second contact surfaces 165, 167 are spaced apart from the adhesive tape 102 thereby preventing touching of the adhesive tape 102 with the cutting blade 160 or the first and second portions 162, 164 except during a cutting event. The positioning of the cutting blade 160 in the recess 163 may also provide a more convoluted path which increases tension during the cutting of the adhesive tape 102.

The first and second portions 162, 164 extend along a height “H” that is defined between the base surface 158 and the corresponding first and second contact surfaces 165, 167. The height “H” of the first and second portions 162, 164 may greater than a height “H1”, “H2” of the cutting blade 160. More particularly, the height “H” of the first and second portion 162, 164 is optionally greater than a maximum height, that is the height “H2”, of the cutting blade 160 such that the cutting blade 160 does not project beyond the first and second contact surfaces 165, 167. Positioning the cutting blade 160 in the recess 163 may provide better guarding of the cutting blade 160 thereby making the cutting section 131 finger safe. Alternatively, the height H2 of the cutting blade 160 can be greater than the height H of the first and second portions 12, 164.

Further, the cutting blade 160 is used to cut the adhesive tape 102. The cutting blade 160 is coupled to the cutting head 156 such that a portion of the cutting blade 160 is disposed above the base surface 158 and remaining portion of the cutting blade 160 is disposed within the cutting head 156. The cutting head 156 defines an elongated slot 166 such that the slot 166 partially receives the cutting blade 160. A thickness of the slot 166 can creates an interference with a thickness of the cutting blade 160 such that the cutting blade 160 is received within the slot 166 by an interference fit. The cutting blade 160 may be easily replaced by pulling an existing damaged cutting blade 160 from the slot 166. In some examples, the cutting blade 160 may be bonded to the head portion 156 using adhesives or fasteners members, without any limitations. It should be noted that the cutting head 156 along with the cutting blade 160 may be replaced for replacing the existing damaged cutting blade since the cutting head is bolted to the frame 118.

The cutting blade 160 is embodied as a standard breakaway utility blade herein. The cutting blade 160 is typically made from a hard and tough material to easily sever the adhesive tape 102. In an example, the cutting blade 160 may be made of a metal or an alloy. In one specific example, the cutting blade 160 may be made of stainless steel. It should be noted that a design of the cutting blade 160 described herein is exemplary in nature, and the cutting blade 160 may include any other shape and/or design.

The cutting blade 160 includes a first end 168 and a second end 170. Further, the cutting blade 160 includes a length “L” that is defined between the first and second ends 168, 170. The cutting blade 160 includes a pair of side portions 172 and a base portion 174. The side portions 172 of the cutting blade 160 have a tapering profile to create a sharp cutting edge 180. The cutting blade 160 is mounted such that the base portion 174 is received in the slot 166 and the pair of side portions 172 are partially received within the slot 166.

Further, the cutting blade 160 has a blade base 176 where the cutting blade 160 intersects with and extends from the base surface 158. The blade base 176 defines a midpoint 178. An X-axis of the tape applicator 100 passes through the midpoint 178 and may be parallel to the blade base 176, such that the X-axis generally extends along the direction “D1” past the cutting head 156. Further, the tape applicator 100 includes a Y-axis extending from the midpoint 178 of the blade base 176 and extending orthogonal to the base surface 158. The tape applicator 100 also defines a Z-axis tangent to the base surface 158, passing through the midpoint 178, and may be parallel to the blade base 176.

The cutting blade 160 has a cutting edge 180 disposed above the base surface 158. The cutting edge 180 is formed at an intersection of the pair of side portions 172. The cutting edge 180 defines a center point 182. In some examples, the cutting edge 180 may include serrations. Further, the cutting blade 160 defines the first height “H1” between the blade base 176 and the cutting edge 180 proximate the first end 168 and the second height “H2” between the blade base 176 and the cutting edge 180 proximate the second end 170. Further, the cutting blade 160 defines a longitudinal blade axis “B1” extending from the midpoint 178 to the center point 182 of the cutting edge 180. The longitudinal blade axis “B1” is generally orthogonal to the base surface 158. Moreover, the tape applicator 100 includes a first angle “A1” greater than 0 degrees between the Y-axis and the longitudinal blade axis “B1”. More particularly, the cutting blade 160 is inclined relative to the base surface 158 such that the first angle “A1” is defined between the Y-axis and the longitudinal blade axis “B1”. The first angle “A1” lies in a range from about 3 degrees to about 8 degrees. In one specific example, the first angle “A1” is approximately equal to 5 degrees. If the first angle “A1” is below 3 degrees, the cutting blade 160 may not allow efficient cutting of the adhesive tape 102. Moreover, if the first angle “A1” is above 8 degrees, a width “W” of the blade slot 190 may have to be increased for accommodating the cutting blade 160 therein during the cutting event of the adhesive tape 102, which may increase a design complexity of the pinching head 184. In the illustrated example, the cutting blade 160 is disposed to define a forward tilt, defined by the first angle “A1”, relative to the Y-axis. In another example, the cutting blade 160 may be disposed to define a rearward tilt, defined by the first angle “A1”, relative to the Y-axis.

Referring now to FIG. 5, the cutting blade 160 defines a cutting edge axis “B2” passing through the center point 182 and tangent to the cutting edge 180. Moreover, the tape applicator 100 includes a second angle “A2” less than 80 degrees between the Z-axis and the cutting edge axis “B2”. In other examples, the second angle “A2” may be less than 60 degrees, 45 degrees, and 25 degrees. More particularly, the cutting edge 180 is inclined relative to the base surface 158 such that the second angle “A2” is defined between the Z-axis and the cutting edge axis “B2”. The second angle “A2” lies in a range from about 10 degrees to about 18 degrees. In one specific example, the second angle “A2” is approximately equal to 12 degrees.

The second angle “A2” may allow improved cutting action of the adhesive tape 102. It should be noted that the second angle “A2” is optimally selected to provide efficient cutting of the adhesive tape 102 without increasing complexity of the cutting section 131. If the second angle “A2” is very shallow, the cutting blade 160 may not demonstrate a cleaner cutting action. Whereas, if the second angle “A2” is very steep, the pinching head 184 may have to travel a comparatively longer path for cutting of the adhesive tape 102. Further, a height “h1” of the blade slot 190 and the height “H” of the first and second portions 162, 164 may also have to be increased in order to accommodate the cutting blade 160 having the steeper second angle “A2”. In some cases, the steeper second angle “A2” may complicate a design and assembly of the cutting section 131. Accordingly, in some cases, the shallow second angle “A2” may be preferred so that the height “h1” of the blade slot 190 and the height “H” of the first and second portions 162, 164 can be shorter and the adhesive tape 102 is not pulled deeply into the blade slot 190 during the cutting event. The shallow second angle “A2” may simplify the tape applicator design and also facilitate clean cutting of the adhesive type 102. In the illustrated example, the cutting edge 180 tapers along the length “L” of the cutting blade 160 such that the first height “H1” of the cutting blade 160 is less than the second height “H2” of the cutting blade 160. In another example, the cutting edge 180 may taper along the length “L” of the cutting blade 160 such that the first height “H1” defined at the first end 168 is greater than the second height “H2” defined at the second end 170.

As shown, the tape applicator 100 also includes the pinching head 184. In the illustrated example, the pinching head 184 is supported by the handle block 120 and is movable relative to the handle block 120. More particularly, the pinching head 184 is movable generally vertical within the handle block 120. The pinching head 184 contacts the non-adhesive side 114 of the adhesive tape 102 during cutting of the adhesive tape 102. The pinching head 184 includes a first pinching projection 186 and a second pinching projection 188 separated by the blade slot 190 having a width W. Moreover, the first and second pinching projections 186, 188 may have a planar profile or a curved profile. The blade slot 190 defines the width “W” and the depth “D”. The cutting blade 160 is in alignment with the blade slot 190. Further, the pinching head 184 includes a base section 192 connected to the first and second pinching projections 186, 188. In some examples, the pinching head 184 may be made of a material, such as aluminum, Delrin®, or any other material, that provides improved traction of the adhesive tape 102 with the first and second pinching projections 186, 188.

Moreover, at least one of the cutting head 156 and the pinching head 184 is movable from a first position with the cutting blade 160 disposed outside of the blade slot 190 to a second position with the cutting blade 160 disposed at least partially within the blade slot 190. The adhesive tape 102 is positioned between the pinching head 184 and the base surface 158 when at least one of the cutting head 156 and the pinching head 184 is in the second position.

In the illustrated example, the cutting head 156 is fixed and the pinching head 184 moves with respect to the cutting head 156 during cutting of the adhesive tape 102. The pinching head 184 is movable between the first and second positions. In the first position, the adhesive tape 102 is free to travel along the adhesive tape path 132 and the pinching head 184, the cutting blade 160, and the cutting head 156 are not in contact with the adhesive tape 102.

Further, the second position is indicative of the cutting event of the adhesive tape 102. More particularly, in the second position, the first and second pinching projections 186, 188 contact the non-adhesive side 114 of the adhesive tape 102. The adhesive tape 102 is positioned between the pinching head 184 and the base surface 158 when the pinching head 184 is in the second position. Further, in some instances, when the cutting blade 160 is completely received within the blade slot 190, the base surface 158 may contact the adhesive side 112 of the adhesive tape 102. As such, the adhesive tape 102 may be nipped between the base surface and the first and second contact surfaces (165, 167).

Further, the tape applicator 100 includes a cutter push button 194 for actuating at least one of the pinching head 184 and the cutting head 156 for cutting the adhesive tape 102. In the illustrated embodiment, the cutter push button 194 is coupled to the pinching head 184. More particularly, the cutter push button 194 is coupled to the base section 192 such that when an operator applies pressure on the cutter push button 194, the pinching head 184 moves along the Y-axis towards the cutting head 156. The cutter push button 194 includes a cap member 196 and a threaded shoulder bolt 198 that is coupled to the base section 192. Further, a spring member 200 is disposed on the shoulder bolt 198 prior to the handle block 120 for biasing the pinching head 184 retracted at least partially within the handle block 120 and out of the adhesive tape path 132 as best seen in FIG. 5.

When the cutter push button 194 is pressed by the operator, the pinching head 184 contacts the adhesive tape 102. Continual movement of the pinching head 184 pushes the adhesive tape 102 towards the cutting blade 160 of the cutting head 156, thereby cutting the adhesive tape 102. Moreover, as mentioned above, during cutting of the adhesive tape 102, the blade slot 190 at least partially receives the cutting blade 160 as the pinching head 184 travels towards the cutting head 156, as illustrated in FIG. 6. Thus, the width “W” and the depth “D” of the blade slot 190 is decided such that the cutting blade 160 can be received within the blade slot 190 without interfering with the first and second pinching projections 186, 188. As the cutting blade 160 does not interact with any other components of the tape applicator 100, except the adhesive tape 102, the cutting blade 160 may have a longer operating life.

It should be noted that the arrangement of the cutting blade 160, the cutting head 156, and the pinching head 184 described herein allows efficient cutting of adhesive tapes having high elongation and low unwind forces. Further, the operator may only press the cutter push button 194 for cutting of the adhesive tape 102. As the cutter push button 194 is distant from the cutting blade 160, any possibility of injury to the operators may be eliminated.

In some embodiments, the length “L” of the cutting blade 160 is greater than or equal to the width, W, of the adhesive tape 102. Such a length will completely severe the adhesive tape at the cutting head 156; however, this may not be desirable since the adhesive tape 102 would then need to be rethreaded around the guide wheel 130 and around the turning board 134 every time the adhesive tape is cut. A standard break-away segmented utility blade having 4-6 blade segments is often a sufficient length to completely sever the adhesive masking tape used for two-tone paint jobs. Four segments work for adhesive tapes up to 0.75″ wide and six segments work for adhesive tapes 1″ wide. Such blades are frequently denoted as “breakaway blades” and are available from McMaster-Carr (item number 38155A71) and are approximately 3⅞ inches long, 9 mm wide (0.354″), 0.02 inches thick, and have 13 breakaway blade segments. Similar blades in various widths, thickness, and segment lengths are available from other suppliers.

In some embodiments, the length “L” of the cutting blade 160 is less than the width of the adhesive tape 102. Such a length will only partially severe the adhesive tape at the cutting head 156. Suitable lengths for L to partially sever the adhesive tape can be from 1 to 3 segments of the breakaway blade and often a single segment of the breakaway blade is all that is needed. For adhesive tapes up to 0.75″ wide one segment to partially sever is sufficient and for adhesive tapes 1″ wide two segments are sufficient to partially sever. In one embodiment, a single segment of the breakaway blade was about 0.2″ long. The partial sever can cut though only one of the edges of the adhesive tape 102 leaving the other edge intact, or preferably the partial sever can only cut through the middle portion of the adhesive tape 102 leaving both edges intact. A standard break-away segmented utility blade having one or two blade segments is often a sufficient length to only partially sever the center portion of the adhesive masking tape used for two-tone paint jobs. Thus, when nearing the end of the curvilinear line the masking tape is being applied along, the operator can actuate push button 196 partially severing the adhesive tape 102 and then continue traversing the adhesive tape applicator 102 along the masking path until the partially severed portion of the adhesive tape 102 clears the tape applicator head 116. Once the partially severed portion has cleared the tape applicator head 116, the operator can actuate the intermittent brake assembly 121 increasing the tape's tension thereby breaking the adhesive tape 102 at the partial sever. Such a mode of operation eliminates the need to rethread the tape applicator 102 after using the cutting section 131.

Now the intermittent brake assembly 121 will be discussed in more detail. The intermittent brake assembly 121 in one embodiment includes a brake shoe 202 attached to a sliding block 204 that rides in a slot in the handle block 120. The brake shoe 204 has a brake pad 206 attached to it. When the brake assembly is actuated by a brake push button 208, the brake pad 206 contacts the non-adhesive side 114 of the adhesive tape as it traverses around the guide wheel 130 creating sliding friction between the brake pad 206 and the adhesive tape 102. The sliding friction increases 30 the tension in the adhesive tape 102 in a tape span 210 between the brake pad 206 and the point of contact of the adhesive tape 102 with the work surface 104 under the pressure pad. The braking tension stretches the adhesive tape 102 in the tape span 210 enabling the operator to apply the adhesive tape 102 along an arc on the work surface 104 without buckling or crinkling the tape. The degree of tension can be controlled by how hard the brake push button 208 is depressed.

The brake is intermittent since it is actuated from an “off” position to an “on” position and will not stay “on” unless continually actuated by depressing the brake push button 208. This allows the operator to add adhesive tape tension when needed to negotiate a curve and then to release the added adhesive tape tension when traversing the tape applicator along a straight line. For tighter curves, more adhesive tape tension can be applied by pushing on the intermittent brake assembly harder. The intermittent adhesive tape brake tension is an additional amount of tape tension to the existing tape tension present from the constant drag of an unwind brake (if present) and any drag present with moving the adhesive tape 102 along the adhesive tape path 132. The intermittent brake has been found effective to not only eliminate wrinkles in the adhesive tape 102 in curves on the work surface 104, but to additionally help with tracking/guiding the adhesive tape 102 when applying it in those curves to maintain the desired offset/placement on the work surface 104 without wandering.

As seen the guide wheel 130 is located in the adhesive tape path 132 and is positioned between the adhesive spool unwind 122 and the tape applicator head 116 such that an adhesive tape 102 will wrap at least a portion of the outer conference of the guide wheel 130. The amount of wrap is often determined by the adhesive tape path, direct or indirect intermittent braking, and tackiness of the adhesive. For example, if indirect braking is used it may be sufficient for line contact of the adhesive tape with the guide wheel and the brake shoe as the shoe squeezes the adhesive tape between it and the guide wheel. When direct braking of the guide wheel is used more adhesive tape wrap may be needed to ensure the adhesive tape does not slide on the guide wheel when the braking force is applied. In general, the wrap angle for the adhesive tape on the guide wheel can be from 0 degrees to 270 degrees, or from 10 degrees to 180 degrees, or from 10 degrees to 150 degrees. In one embodiment, the wrap angle was 120 degrees.

Alternative intermittent brake assemblies can be provided. For example, the intermittent brake assembly 121 could brake the guide wheel 130 directly and not touch the adhesive tape 102 using a similar system where the brake pad 206 directly contacts the outer circumference of the guide wheel 130. The adhesive tape 102 could be guided to one side of the guide wheel 130 while the brake pad 206 contacts the other side of the guide wheel 130. These two sides may be opposing or adjacent to each other on the guide wheel 130. Such a system may be preferred if the static coefficient of friction for the non-adhesive side 114 of the tape varies widely for different adhesive tapes being used to have a more consistent braking force. For example, a creped paper backing layer versus a film backing layer on the adhesive tape 102. An internal braking shoe on the guide wheel 130 similar to a drum brake on an automobile may be used. Many other braking systems can be adapted as needed.

Similar to the cutter push button 194, the brake push button 208 is coupled to the brake shoe 202. More particularly, the brake push button 208 is coupled to the sliding block 204 such that when an operator applies pressure on the brake push button 208, the sliding block 204 moves along the Y-axis towards the guide wheel 130. The brake push button 208 includes a cap member 212 and a threaded shoulder bolt 214 that is coupled to the sliding block 204. Furthermore, a spring member 216 is disposed on the shoulder bolt 214 prior to the handle block 120 for biasing the sliding block 204 retracted at least partially within the handle block 120 and out of the adhesive tape path 132 as best seen in FIG. 5.

The brake assembly 121 can be tuned to apply only a limited amount of braking force to the adhesive tape 102. If too much force is applied, the adhesive tape 102 in the tape span 210 may quickly exceed its yield strength and snap or be permanently inelastically deformed. Thus, unlike conventional brake systems where the goal is often to maximize as much as possible the braking force created, the brake assembly 121 is preferably tuned so as to not be able to easily stall the progression of the adhesive tape 102 while traveling along the adhesive tape path 132. Desirably the intermittent brake assembly 121 is tuned to have a shallow and linear response in relation to the force applied to the brake push button 208.

One way to limit the generated brake force is to design the brake shoe 202 with a radius of curvature “RS” greater than a radius of curvature “RW” for the guide wheel 130. If the brake shoe 202 has a radius of curvature RS approaching infinity, only line contact between the brake shoe 202 and the guide wheel 130 occurs producing the least amount of brake force. If the brake shoe 202 has the same radius of curvature as the guide wheel, RS=RW, then the maximum amount of braking force occurs; especially, as the length of the brake pad 206 is increased. In various embodiments of the invention, the ratio of RS/RW can be from 1000 to 1.5, or from 500 to 2, or from 100 to 2.5, or from 10 to 3. In one embodiment, the brake shoe 202 had an RS of 2.5 inch and the guide wheel 130 had an RW of 0.375 such that RS/RW=6.67. Note that it is envisioned that the radius of curvature of the brake pad 206 is the same as that of the brake shoe 202. If there are differences in these radii, the radius of curvature of the brake pad 206 should be used instead.

Another way to limit the generated brake force is to select the brake pad's static coefficient of friction to be relatively low such that the adhesive tape 102 still slides relatively easily in the nip between the brake pad 206 and the guide wheel 130. In particular, it was found that if static coefficient of friction for the brake pad was greater than about 0.3 the brake was “too grabby” and easily stalled the adhesive tape 102 such that it would no longer feed from the unwind 122 to the work surface 104. Thus, the static coefficient of friction for the brake pad 206 is preferably greater than 0.0 and less than 0.3. Suitable brake pad materials are thin films of ultra-high molecular weight polyethylene (UHMWPE) or polytetrafluoroethylene (PTFE) having static coefficients of friction of about 0.12 and about 0.08. In one embodiment, the brake pad material was UHMWPE. The static coefficient of friction can be determined by consulting appropriate material handbooks. It should be noted that the radius of the brake shoe effects the choice for the static coefficient of friction. Larger brake shoe wraps on the guide wheel may require lower friction materials while lower brake shoe wraps or line contact may require higher friction materials.

Another way to tune the adhesive tape's elongation is to control the length, “LS” of tape span 210 after the brake pad 206 until the adhesive tape is adhered to the work surface 104. If the tape span LS is too short, insufficient stretching/elongation may occur such as by braking the adhesive tape 102 immediately prior to the pressure pad in the tape applicator head 116. Thus, a short tape span at low elongation may not stretch the adhesive tape enough to apply it in a tight curve without crinkling. If the tape span LS is too long, it may be harder to precisely control the additional added tape tension as other tape guiding components that the adhesive tape 102 interacts with along the adhesive tape path 132 may not have a linear response to the additional tape tension with regard to their frictional characteristics. For example, using an unwind brake in an “on/off” manner will likely lead to poor results and just increase the overall drag/difficulty when using the tape applicator 100. In various embodiments of the invention, the tape span's length, LS, can be from 0.5″ to 20″, or from 1″ to 10″. In one embodiment, the tape span length, LS, was about 7 inches.

FIG. 8 illustrates a method of using the tape applicator 100 when applying the adhesive tape 102 to a work surface 104. As seen, the steps for applying and tracking the tape applicator 100 along both a curved line and a straight line and severing the adhesive tape 102 are shown. The steps need not be completed in any particular order and not all steps need to be undertaken. For example, it may not be necessary to cut adhesive tape with the on-board cutter if an operator prefers to do it by hand. Not all painting jobs require masking curved lines so it may not be necessary to use the intermittent brake assembly unless cutting the adhesive tape.

The tape applicator 100 described herein includes a reversible design. Accordingly, the tape applicator 100 may be adapted to apply the adhesive tape 102 while moving the tape applicator 100 from a left hand side to a right hand side of work surfaces or from the right hand side to the left hand side work surfaces, as per requirements. For example, all of the major assemblies bolted to the right side of frame 118 may instead be relocated and bolted to the left side of frame 118 instead. The tape applicator head 116 may be symmetric with a rounded turning surface 138 located on both sides of the tape applicator head 116 to allow the major assemblies to be switched to the opposing side of the frame.

In one example, all components of the tape applicator 100 may be manufactured using a three-dimensional (3D) printing technique. For example, the components of the tape applicator 100 such as the handle block 120, the turning board 134, the cutting head 156, the pinching head 184, and the brake assembly 121 may be manufactured by 3D printing and later assembled to form the tape applicator 100. In another example, the plastic portions of tape applicator 100 is entirety 3D printed.

It should be noted that the components of the tape applicator 100 may be manufactured using other methods such as injection molding, without limiting the scope of the present disclosure. The 3D printed components may be printed using standard Acrylnitril-Butadien-Styrol (ABS). Further, the tape applicator 100 described herein is light in weight, compact in size, and easy to use. Further, the tape applicator 100 allows operators to apply fine line tapes quickly and accurately to mask lines where there is a two-tone paint scheme. Moreover, the tape applicator 100 includes an interlocking design thereby providing a compact and strong handheld tool.

The tape applicator described herein may also be used for end of arm tooling in robotic applications for applying the adhesive tape to the automobile. In such situations, appropriate brackets can be used to mount the adhesive tape dispenser instead of the supplied handles of grasping. Additionally, a solenoid, torque motor, or other proportional device can be used to apply a variable force to the brake shoe.

The tape applicator 100 described herein may be used to apply adhesive tapes on various surfaces, including but not limited to, frame members of a vehicle. The cutting section 131 of the tape applicator 100 described in this disclosure may be used to cut adhesive tapes having low unwind forces and high elongation quickly and easily, thereby increasing usability and product reliability. The intermittent braking assembly 121 of the tape applicator 100 described in this disclosure may be used to stretch adhesive tapes having low unwind forces and high elongation quickly and easily when applying the adhesive tape 102 in an arc or curve.

TAPE APPLICATOR AND METHOD OF USING

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