EP0459654A1

EP0459654A1 - Hand-held automatic tape applicator

Info

Publication number: EP0459654A1
Application number: EP91304308A
Authority: EP
Inventors: Robert A. c/o Minnesota Mining and Luhman; Richard L. c/o Minnesota Mining and Patten
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee: 3M Co
Priority date: 1990-05-14
Filing date: 1991-05-14
Publication date: 1991-12-04
Also published as: JPH0496460U

Abstract

A tape applicator having a handle and a housing is disclosed. A rotatable toothed gear is located in the housing and houses a tape roll. A pawl is engagable with the gear teeth of the toothed gear to alternately prevent and permit rotation of the tape roll. An applying arm assembly projects the tape out of the housing to dispense the tape and withdraws the tape into the housing after some of the tape is dispensed. A trigger is mounted on the handle and is connected to the pawl and the applying arm. Retraction of the trigger into the handle disengages the pawl from the gear teeth and pivots the applying arm to the extended position. After application of the tape, extension of the trigger pivots the applying arm to the withdrawn position to move the tape into a position in which a fixed cutting blade severs the tape.

Description

TECHNICAL FIELD

The present invention relates to hand-held automatic tape applicators. More particularly, the present invention relates to tape applicators in which tape can be precisely positioned on and applied to a work surface without contacting the hands of a user, and in which the tape end is withdrawn into the applicator after each application.

BACKGROUND OF THE INVENTION

The use of various tapes such as masking tape, cellophane tape, packing tape, adhesive transfer tape in which the tape is removed from the adhesive to yield a double-sided adhesive, and other types of tapes has given rise to a plethora of hand-held devices to store, dispense, and apply the tapes. Early devices were simply dispensers which stored the tape in a convenient fashion to facilitate manual dispensing of the tape from the dispenser prior to manual application of the tape onto a work surface. These devices require the tape to be handled by a user or operator. That is, the user must grab the end of the tape and pull it out of the dispenser and then must apply the tape by hand. This damages and reduces the effectiveness of the adhesive on the tape.
Hand-held tape dispensers and applicators have been designed to apply the tape directly onto a work surface without first removing a tape segment from the applicator. U.S Patent No. 4,238,271 to Urushizaki discloses one adhesive tape applicator which uses a belt to assist tape application. However, this applicator requires the end of the tape to be manually pulled out of the applicator, thereby degrading the adhesiveness of the tape. Additionally, this applicator uses a rotatable cutting blade to sever the tape, adding further complexity to the applicator. Also, the end of the tape remains exposed until the next application, thereby collecting dust and dirt which further degrades the adhesive characteristics of the tape. Monzo Gomez, U.S Patent No. 4,486,263 discloses a similar tape dispenser having a linearly displaceable cutting blade. Like Urushizaki, the end of the tape remains exposed to collect dirt and debris between uses.
Wilkie, U.S. Patent No. 4,762,586 is directed to a combination tape applicator and tape dispenser having a stationary cutting blade with a movable blade guard. This apparatus requires the tape to be removed by hand and affords little tape control as the entire tape roll is required to slide within the housing.
U.S. Patent No. 4,792,375 to Lin discloses an automatic tape cutter in which the tape is dispensed without contacting the hands of the user and in which the tape is withdrawn into the applicator after each use. However, in operation, the end of the tape frequently withdraws too far into the cutter thereby requiring that the cutter be opened and the tape manually rethreaded in the opening. Furthermore, this device is unduly complex. The cutter requires two shell body portions which pivot with respect to each other to displace the entire tape roll within the cutter body. This tape roll movement reduces tape control during application. There is also a large gap between a ramming cylinder, which applies the tape to a work surface, and a guide bar, which guides the tape toward a tape deflection roller. This large unsecured gap further reduces tape control as it requires the tape to bridge these two elements without any supporting nip. Additionally, this device uses a rotary cutting knife which tends to cause the end of the tape to shift laterally during cutting.
Iiyama, et al., U.S. Patent No. 4,345,966 is directed to a hand-held tape applicator in which the tape may be dispensed without contacting the hands of the user and in which the tape is withdrawn into the applicator after each use. Like Lin, there is a large unsecured gap between a tape deflection roller, which applies the tape to a work surface, and a tape support roller, which guides the tape toward the tape deflection roller. This reduces tape control. Moreover, the entire tape roll must translate within the housing to dispense tape, further reducing control over the tape. Furthermore, a separate tape press roller is required to press the tape onto the work surface. Additionally, this device uses a moving cutting blade which tends to cause the end of the tape to shift laterally during cutting.
While these tape dispensers may be adequate for dispensing relatively stiff tapes, it is believed that none of the devices can adequately dispense adhesive transfer tape without damaging or prematurely removing the delicate liners associated with this tape. Additionally, none of these devices is simply constructed with a fixed cutting blade and with a stationary tape roll. Moreover, none of the devices combines construction simplicity with a device in which the location of the tape is precisely selectable and adjustable before the tape contacts the work surface; none of the devices permits the movement of the applicator after the applicator is initially positioned on a work surface without damaging the tape and/or the work surface.

SUMMARY OF THE INVENTION

The deficiencies of the prior art tape applicators are overcome by the hand-held applicator of the present invention. The applicator is used for applying a tape onto a work surface by straight line movement of the applicator across the work surface. The applicator is particulary suitable for the application of adhesive transfer tape. Prior to dispensing the tape, the tape is located completely within the applicator and cannot contact the work surface until the tape is caused to project out of the applicator housing. Thus, the applicator can be precisely positioned and adjusted against the work surface before the tape contacts the work surface, and the tape is dispensed without the hands of the user contacting the tape.
The applicator includes a handle connected to a housing. A tape roll is mounted on a tape drum disposed in the housing. A rotatable toothed gear assembly is located in the housing and the tape drum is connected to the gear assembly. A pawl is engagable with the gear teeth of the toothed gear assembly, such that when the pawl engages the gear teeth the tape roll is prevented from rotating. When the pawl disengages from the gear teeth the tape roll is free to rotate with the tape drum and the gear assembly.
The applicator also includes an applying arm assembly having an applying arm which moves the tape to an opening in the housing to dispense the tape and withdraws the tape into the housing after a length of the tape is dispensed. This permits the tape to be contained completely within the housing and out of contact with the work surface prior to dispensing the tape. Therefore, the applicator can be precisely positioned and adjusted against the work surface before the tape contacts the work surface. A cutting blade is fixed in the housing and the tape is drawn into contact with the blade by the applying arm as the tape is withdrawn into the housing.
A trigger is mounted on the handle and is biased toward a position extending out of the handle. The trigger is connected to the pawl so that retraction of the trigger into the handle disengages the pawl from the gear teeth permitting rotation of the tape roll. Retraction of the trigger also pivots the applying arm from the withdrawn position to the extended position to position the tape for application onto the work surface. After application of the tape onto the work surface, extension of the trigger out of the handle pivots the applying arm to the withdrawn position which moves the tape into contact with the cutting blade. Continued straight line movement of the applicator causes the cutting blade to sever the tape applied to the work surface from the remaining tape within the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective view of a tape applicator according to the present invention.
Figure 2 is a side view of the tape applicator of Figure 1 with the cover removed to illustrate the various elements and with the applicator elements in a rest position.
Figure 3 is a side view of the tape applicator of Figure 1 positioned adjacent a work surface with a portion of the cover removed and the applicator elements in position to apply tape.
Figure 4 is a front view of the tape applicator of Figure 1.
Figure 5 is an enlarged front view of the tape applicator of Figure 1 similar to Figure 4 but with parts shown in section and with the cutting blade removed for clarity.
Figure 6 is a cross-sectional view of the tape applicator taken along line 6-6 of Figure 2 with parts shown in full elevation.
Figure 7 is a cross-sectional view of the tape applicator taken along line 7-7 of Figure 2.
Figure 8 is a perspective view of the tape applicator of Figure 1 with the housing cover open.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The figures illustrate a tape applicator 10 according to one embodiment of the present invention. The tape applicator 10 can be used with various types of tape such as transparent tapes, packing tapes, double-sided tapes and adhesive transfer tapes. As illustrated, the applicator 10 is used with adhesive transfer tapes.
Figure 1 and Figure 4 show the applicator 10 fully assembled. The applicator 10 includes a casing 12 having a base member 14 and covers 16a and 16b. The casing 12 is also characterized by its housing 18 and its handle 20. The base member 14 forms the entire base side of the housing 18 and handle 20 while the cover 16a encloses the housing 18 and the cover 16b encloses the handle 20. The cover 16b is connected to the base member 14 by any suitable connection such as screws 11 threaded into respective bosses 13. The cover 16a is hinged to the base member 14 by a living hinge 21a and is secured to the base member 14 by a latching mechanism 21b. The hinge 21a is shown as a separately formed element inserted into respective slots 15a and 15b on the base member 14 and the cover 16a. However, the base member 14, hinge 21a, and cover 16a can be formed as one piece.
Housing 18 includes windows 22a and 22b which permit viewing the operation of the applicator 10. One window 22a is formed in the cover 16a and is used to view the amount of tape remaining on its tape roll 30 in the housing 18. The other two windows 22b are located adjacent an opening 23 in the housing 18 through which tape is dispensed and are used to position the applicator 10 on a work surface. Preferably, the windows 22a, 22b are simply openings in the plastic which forms the housing 18, although transparent inserts or coverings can be used. Alternatively, indicia can be formed or printed on the outside of the housing 18 to align the tape 32. The opening 23 also serves to square the applicator 10 with a work surface.
The handle 20 includes a grip portion 24 formed by spaced ridges 24a and is ergonomically shaped and angled with respect to the housing 18 to facilitate holding and operation. The handle 20 is connected to the housing 18 at an angle ranging from 50° to 60° with respect to the vertical when the opening 23 is in the applying position parallel to a horizontal surface. This angle is designed to place the applicator 10 comfortably in the hand of a user to maintain a straight wrist when operating the applicator 10.
Figure 2 shows the applicator 10 with its covers 16a, 16b removed to illustrate the elements of the applicator 10. In Figure 2, the elements are positioned in a rest position in which tape is not dispensed. A boss 26 is molded directly to the base member 14 in the housing 18, and a tape drum 28 is rotatably mounted on the boss 26. A tape roll 30 having a core 31 is mounted on the tape drum 28 so that there is no relative rotation between the tape roll 30 and the tape drum 28. Relative rotation is prevented by a tab 35 formed outside of and concentric with the tape drum 28. The tab 35 extends preferably for a 45° to 60° arc and is received within cavities formed in the core 31. To hold the tape roll 30 on the tape drum 28, the tape drum 28 includes a resilient member 34 which includes a shoulder to capture the core 31. A circular gear 36 having gear teeth 38 disposed around the entire periphery is fixed to the tape drum 28. The gear 36 and tape drum 28 may be formed as a single component.
A finger-activated trigger 40 is mounted in the handle 20. The trigger 40 pivots around its lower end 42 which is mounted on a pivot pin 44 fixed to the base member 14 of the handle 20. The trigger 40 extends from its lower end 42 to an upper end 46 located adjacent the gear 36. Near the upper end 46, the trigger 40 is formed with a return spring guide 48 which secures a return spring 50 between the trigger 40 and the wall of casing 12. The return spring 50 biases the trigger 40 in an extended position shown in Figure 2. Squeezing the trigger 40 acts against the force of the return spring 50 to withdraw the trigger 40 into the handle 20.
A pawl 52, which is engagable with the gear teeth 38 of the gear 36, is connected to the upper end 46 of the trigger 40, and is preferably formed integrally with the trigger 40. When the applicator 10 is at rest, the trigger 40 is biased in its extended position and the pawl 52 engages the gear teeth 38. Thus, the gear 36, and therefore the tape drum 28 and tape roll 30, are prevented from rotating. When the trigger 40 is squeezed and withdrawn into the handle 20, the pawl 52 disengages from the gear teeth 38, allowingthe gear 36, the tape drum 28, and the tape roll 30 to rotate.
The tape 32 is dispensed from the applicator 10 and is applied onto a work surface 54 through the opening 23 by an applying assembly 56 which includes an applying arm assembly 58 and a pair of rollers which guide the tape 32 in housing 18. The applying arm assembly 58 includes an applying arm 60 which is mounted for pivoting motion at a fixed end 62 around a pivot pin 64. The applying arm 60 is formed as two halves 61a, 61b each forming a side wall but with an open upper surface 60a to minimize adherence of the tape 32 to the applying arm 60 as the tape is dispensed. However, it is intended that the tape 32 span across the entire length of the upper surface 60a without any contact. The applying arm 60 is withdrawn as shown in Figure 2 when the trigger 40 is extended. When the trigger 40 is retracted as shown in Figure 3, the applying arm 60 pivots around the pivot pin 64 to its extended position which presents the tape 32 to the opening 23 for application.
The applying arm 60 is connected to the trigger 40 through a connecting arm 66 shown in Figures 2, 3, and 7. The connecting arm 66 is connected to the applying arm 60 through a connection point 68 on the applying arm 60 adjacent the pivot pin 64. The connecting arm 66 is connected to the trigger 40 through a connection point 70 at or adjacent the upper end 46 of the trigger 40. As shown, the connecting arm 66 is a rod which passes through bores which form the connection points 68, 70.
A pair of rollers 72, 74 are part of the applying arm assembly 58 and are mounted at the free end 76 of the applying arm 60, as shown in Figures 2, 3, 4, and 5. The applying roller 72 is cantilever mounted on the free end 76 of the longer applying arm half 61b. The applying roller 72 can be formed of silicone rubber tubing around a plastic mandrel to reduce friction. The nip roller 74 is spaced from the applying roller 72 toward the applying arm fixed end 62 and rotates on a pin (not shown) held between the two applying arm halves 61a, 61b. The nip roller 74 provides a nip between itself and the applying roller 72 to control lateral movement of the tape 32 therebetween. This arrangement is superior to those of known applicators and dispensers which do not control the tape through a nip. Alternatively, the applying roller 72 may be replaced with a nonrotating, fixed member having an arcuate periphery along which the tape 32 slides.
The nip roller 74 is secured within the applying arm 60 at both of its ends. The nip roller 74 has a smaller diameter than the applying roller 72 and is formed with a roughened, low release surface which prevents it from removing adhesive from the liner of the tape 32. This is a particular problem when applying adhesive transfer tape because in known dispensers the component equivalent to the nip roller 74 contacts the adhesive side of the tape. The nip roller 74 preferably is formed with a non-stick plasma treated surface. Plasma treating is applied by spraying and heating a non-stick coating preferably including polytetraflouroethylene. This surface provides more control over tape placement as tape 32 is being applied by permiting the tape 32 to unwind and rest against the nip roller 74 without adhering to it. Additionally, when applying adhesive transfer tape, this plasma treated surface 78 prevents the adhesive from being removed from the liner.
Before the tape 32 reaches the applying roller 72, it passes around a backup roller 80 and a wrap roller 82 which are part of the applying assembly 56. As shown in Figures 2, 3, and 6, these rollers 80, 82, rather than the sides of the housing 18, combine to guide the tape 32. This guiding method reduces damage to the tape edges by preventing the tape 32 from contacting the sides of the housing 18. Thus, the nip between the nip roller 74 and the applying roller 72 combines with the backup roller 80 and the wrap roller 82 to prevent lateral tape movement of the tape 32 within the nip. The backup roller 80 also controls the position of the cut or leading end of the tape 32 by withdrawing the cut end into the applicator housing 18. As the trigger 40 pivots the applying arm 60 to its withdrawn position, the tape 32 adheres to and wraps around the backup roller 80. This protects the tape by preventing the tape 32 from tangling in the applicator 10. This also lengthens the tape path and positions the tape end at or slightly forward of the tangential contact point 72a of the applying roller 72, as shown in Figure 3. This location is critical to beginning the next tape application because tape extending far past this tangential contact point would not be pressed onto the work surface 54 by the applying roller 72.
A cutting blade 84, best shown in Figures 2, 3, and 4, is fixed in a corner of the housing 18. After application of the tape 32, release of the trigger 40 to its extended position moves the applying roller 72 past the cutting blade 84. This motion, combined with continued motion of the applicator 10 across the work surface 54, moves the tape 32 against the cutting blade 84 and severs the tape. Preferably, the cutting blade edge lies in a plane at a nonperpendicular angle greater than 80° with the plane of the base member 14, and perpendicular to the tape 32 as the tape 32 passes across the blade 84. Additionally, the edge of the cutting blade 84 is not parallel with the surface of the tape 32 to facilitate a "pull-and-tear" cutting method wherein the tape 32 is cut from one edge of the tape to the other, rather than simultaneously across the entire width of the tape 32 to yield square, uniform tape cuts. The tape 32 is preferabaly cut from the side adjacent the base member 14 to which the blade 84 is fixed.
The tape 32 used with the applicator 10 follows a tape path extending from the tape roll 30 with the adhesive side of the tape 32 facing outwardly, toward the trigger 40. Alternatively, the tape 32 can extend from the tape roll 30 with the adhesive side of the tape 32 facing inwardly, as long as the tape 32 then follows the same tape path described below. The tape 32 passes from the roll 30 and around the wrap roller 82 with the non-adhesive side contacting the wrap roller 82. The tape 32 then passes between the wrap roller 82 and the backup roller 80, and over the backup roller 80 with the adhesive side of the tape 32 contacting the backup roller 80. The tape 32 next passes across the top of the applying arm 60 with the adhesive side disposed against the applying arm 60 although the applying arm open upper surface 60a reduces any contact and adhesion of the tape 32. The tape 32 then passes over the nip roller 74 and between the nip formed between the nip roller 74 and the applying roller 72. The tape 32 extending through this nip can be applied to the work surface 54 through the opening 23.
The tape roll 30 is inserted into the applicator 10 by placing the tape roll 30 on the tape drum 28 so that the tab 35 prevents relative rotation therebetween. The end of the tape 32 is threaded along the tape path so that the tape end extends through the nip between the applying roller 72 and the nip roller 74. When the applicator 10 is not in use, the trigger 40 is biased by the return spring 50 in its extended position. In this position, the pawl 52 engages the gear teeth 38, thereby preventing the gear 36, tape drum 28, and tape roll 30 from rotating. Also, the applying arm assembly 58 assumes the withdrawn position shown in Figure 2.
To apply tape, the applicator 10 is positioned on the work surface 54 as shown in Figure 3. The opening 23 through which the tape 32 is applied is aligned with the beginning point of taping, as the window 22b assists locating the applicator 10. As the tape 32 does not yet extend out of the applicator 10, the applicator 10 can be placed and replaced to properly align the tape 32 without the tape contacting the work surface 54 or being wasted.
After alignment, the trigger 40 is retracted into the handle 20 as shown in Figure 3. This disengages the pawl 52 from the gear teeth 38, and frees the gear 36, the tape drum 28, and the tape roll 30 for rotation, and the tape 32 for dispensing. Retracting the trigger 40 also pivots the applying arm assembly 58 to its extended position. This moves the applying roller 72 and the tape 32 adjacent thereto to the opening 23. Movement of the applying roller 72 is along a curved arc traversed by the applying arm 60 and places the adhesive side of the tape 32 onto the work surface 54. The applicator 10 is then pulled in a straight line to apply the tape 32, and the applying roller 72 presses the tape 32 onto the work surface 54 to buff the tape 32 and enhance adhesion.
After the tape 32 is applied, the tape applied to the work surface 54 is severed. The applicator 10 provides an accurate method for locating the end of the tape being applied. When the linear applying motion of the applicator 10 ceases and before the applying roller 72 is withdrawn from its applying position, the applying roller contacts the work surface 54 through the tape 32 at a final tangential contact point 72a which is visible through the windows 22b. Cutting occurs at this tangential point 72a. Cutting is performed by allowing the trigger 40 to extend and continuing the applying motion of the applicator 10. As the trigger 40 extends out of the handle 20 to withdraw the applying arm 60, the applying arm 60 positions the tape 32 at a 90° angle with the cutting blade 84 for cutting at the final tangential point 72a.
It is preferred to operate the applicator 10 so that the front surface of the housing 18 having the opening 23 slides along the work surface 54 during the application of tape, as described above. However, the applicator 10 also can be operated with this front surface spaced above the work surface 54 such that the applying roller 72 extends at least partially through and projects the end of the tape 32 through the opening 23. The projection of the applying roller 72 onto the work surface 54 causes the housing 18 to lift up from the work surface 54 while the applying roller 72 rolls the tape 32 onto the work surface 54.

Claims

A hand-held applicator for applying tape from a tape roll having a core onto a work surface by straight line movement of the applicator across the work surface, the applicator comprising:
a housing including an opening;
a tape drum disposed in the housing on which the tape roll is fixedly mounted for rotation around its axis;
a handle connected to the housing for grasping by a user;
means for projecting the tape to the housing opening to dispense the tape and for withdrawing the tape into the housing after some of the tape is dispensed, wherein the projecting means is movable between a withdrawn position in which it retains the tape completely within the housing and prevents the tape from contacting the work surface before dispensing, and an extended position in which the tape is projected to the housing opening, whereby the applicator can be precisely positioned and adjusted against the work surface before the tape contacts the work surface, and the tape is dispensed without the hands of the user contacting the tape;
means for cutting the tape applied to the work surface from the tape remaining in the housing, wherein the cutting means is fixedly mounted in the housing; and
means for moving the projecting means between the first and second positions.
The applicator of claim 1 wherein the handle is connected to the housing at an angle between 50° and 60° with respect to the vertical when the applicator opening is in an applying position parallel to a horizontal work surface.
The applicator of claim 1 further comprising means for preventing the tape roll from rotating relative to the tape drum.
The applicator of claim 3 wherein the tape roll core includes cavities and the rotation preventing means comprises a tab extending axially from the tape drum and into the tape roll cavities.
The applicator of claim 1 wherein the activating means comprises a trigger mounted on and biased in a position extending out of the handle and connected to the projecting means such that retraction of the trigger into the handle causes the projecting means to project the tape to the housing opening.
The applicator of claim 5 wherein the projecting means comprises an applying arm assembly having an applying arm which pivots from a withdrawn position to an extended position in response to retraction of the trigger into the handle to project the tape to the housing opening for application of the tape onto the work surface, and a plurality of rollers mounted in the housing which guide the tape within the housing.
The applicator of claim 6 wherein the applying arm assembly comprises a connecting arm connecting the applying arm to the trigger.
The applicator of claim 6 further comprising an applying member having an arcuate periphery which applies the tape to the work surface and presses the applied tape on the work surface.
The applicator of claim 5 further comprising a toothed gear assembly on which the tape drum is mounted for rotation therewith, and a pawl engagable with the gear teeth of the toothed gear assembly, wherein the trigger is connected to the pawl such that retraction of the trigger into the handle disengages the pawl from the gear teeth to free the tape roll for rotation with the tape drum and extension of the trigger causes the pawl to engage the gear teeth to prevent the tape roll from rotating.
The applicator of claim 5 wherein the trigger is connected to the projecting means such that retraction of the trigger into the handle causes the projecting means to project the tape to the housing opening, and wherein after application of the tape, extension of the trigger out of the handle causes the projecting means to position the tape adjacent to the cutting means such that continued straight line movement of the applicator after extension of the trigger out of the handle causes the the cutting means to sever the tape applied to the work surface from the tape remaining in the housing.