Abstract:
An adhesive tape dispenser is comprised of a dispensing body that provides for the loading of a roll of tape at its rear portion and a blade mounted on the dispensing body. A roller, a guide wheel, and a pawl are respectively pivotally mounted in the dispensing body. The roller has a plurality of protrusions arranged around one end thereof. The pawl has a pressing member capable of positioning against the circumferential face of the roller as well as an engaging portion capable of becoming engaged between two protrusions of the roller, and the pawl is postured to the rear by an elastic member. Tape is inserted between the roller and the pawl and then routed pass the guide wheel to the area of the blade and when it is applied forward, the roller correspondingly rotates forward in the same direction and the protrusions allow the engaging portion to slide over them. Since the rear side of the pawl is engages the protrusions, counter rotation by the roller is not possible and tape is not retracted in the opposite direction.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates generally to tape dispensing devices, specifically to an adhesive tape dispenser with anti-reverse roll rotation capability.  
         BACKGROUND OF THE INVENTION  
         [0002]    Post offices, the delivery industry, and factory shipping departments utilize large width adhesive tape to seal packages (the widest type is used to tape carton bottoms). Due to the intensity of such operations, handheld adhesive tape dispensers are typically utilized for such sealing to simplify and quicken the drawing out of tape applied onto packages.  
           [0003]    However, conventional adhesive tape dispensers are often troublesome to utilize. Since the roll of tape in the dispenser rotates freely, if the rotational direction of the adhesive tape roll is reversed due to angular disposition or an unanticipated application of external force, the small portion at end of the tape spindles back and sticks onto the circumferential surface of the adhesive tape roll. As such, it is necessary to undertake the arduous ordeal of once again finding the end of the adhesive tape during usage.  
         SUMMARY OF THE INVENTION  
         [0004]    The primary objective of the present invention is to provide an adhesive tape dispenser with anti-reverse roll rotation capability that effectively prevents the end of the adhesive tape from spindling back and clinging to the circumferential surface of the adhesive tape roll to thereby increase convenience during utilization.  
           [0005]    To achieve the objective, the adhesive tape dispenser provided by the present invention is comprised of a dispensing body having a pivot for pivotally mounting a roll of tape thereon and a stop portion, a roller, a pawl, an elastic member, a guide wheel and a blade. The roller is pivotally mounted in the dispensing body and has a plurality of protrusions arranged around the axis thereof at one end. The pawl is pivotally hinged in the dispensing body and has a pressing member which has an edge against the periphery of the roller, and an engaging portion at one end thereof which is capable of engaging in between two said protrusions. The pawl is stopped at said stop portion of the dispensing body when the pawl is pivoted backwards, thereby preventing the roller being rotated backwards. The elastic member is mounted in the dispensing body and adapted to force said pawl to be pivoted backwards. The guide wheel is pivotally mounted in the dispensing body and disposed in front of the roller. The blade is mounted on the front end of the dispensing body. The tape is inserted between the periphery of the roller and the pressing member of the pawl and then routed over the periphery of the guide wheel to the blade. The roller is rotated forwards when the roll of tape is rotated forwards during application such that the engaging portion of said pawl is pushed forwards by the protrusions of the roller and then engages in between the next two said protrusions. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    [0006]FIG. 1 is a side view of a preferred embodiment of the present invention.  
         [0007]    [0007]FIG. 2 is a sectional view of the preferred embodiment of the present invention, showing a roll of adhesive tape is loaded and ready for dispensing.  
         [0008]    [0008]FIG. 3 is a top view of the preferred embodiment of the present invention.  
         [0009]    [0009]FIG. 4 is a sectional view taken along line  4 - 4  in FIG. 2.  
         [0010]    [0010]FIG. 5 is an enlarge view of a portion of the preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0011]    Referring to all the drawings, the adhesive tape dispenser of a preferred embodiment of the present invention is comprised of a dispensing body  10 , a tape cover  20 , a roller  30 , a pawl  40 , an elastic member  50 , a guide wheel  60 , a blade  70  and a blade cover  80 .  
         [0012]    The dispensing body  10 , as indicated in FIGS.  1 - 3 , comprises a main member  11  and a secondary member  17  that are assembled together. The main member  11  has a main portion  12 , a hollow, tubular pivot  13  projecting perpendicularly from the rear lateral end of the main portion  12  that is utilized for mounting a roll of tape T (as shown in FIG. 2), a plurality of post- or curved planar fastening portions  14  projecting along the front lateral end of the main portion  12 , a platelike stop portion  15  protruding from the center area of the main portion, and a tape rest portion  16  extending from the bottom edge of the main portion. The secondary member  17  has a main portion  18  and a plurality of corresponding fastening portions  19  projecting from one side of the main portion  18 . The main portion  18  of the secondary member  17  is disposed parallel to the main portion  12  of the main member  11  and, furthermore, its fastening portions  19  are firmly fastened to the corresponding fastening portions  14  of the main member  11  by means of screws  91  so as to form the dispensing body  10 .  
         [0013]    The tape cover  20  is a rectangular plate having one end slightly curved, and the other end of which is pivotally conjoined to the top side of the dispensing body  10  such that the curved end of the tape cover  20  covers the upper extent of the roll of tape T and is capable of being turned upward.  
         [0014]    Please refer to FIGS.  4 - 5 , the roller  30  is cylindrical in shape and has a pivot hole  31  through its axial center, a shaft  32  is inserted through the pivot hole  31  and its inner extremity is perpendicularly embedded into the main portion  12  of the main member  11  of the dispensing body  10  (as shown in FIG. 4) such that the roller  30  is capable of rotating in place adjacent to the front end of the dispensing body  10  and its outer end is visible at the lower extent of the main portion  18  of the secondary member  17 . The roller  30  has a plurality of grooves  33  extend in an axially oriented, even distribution along the circumferential face of the roller  30  and the sectional profile of each groove  33  is triangular. In addition, a plurality of protrusions  34  are formed at equal angles apart in the end edge around the axis of the roller  30 , the quantity of which is equal to that of the grooves  33 . As viewed from the end face of the roller (as shown in FIG. 2 and FIG. 5), the protrusions  34  and the grooves  33  are arranged in alternation. Furthermore, the outer sides of the protrusions  34  farther from its axial center are gradually diminished in shape.  
         [0015]    The pawl  40  having a shaft  41 , a pivot hole  41  through the shaft  41 , and a pressing member  43  extending from the outer portion of the shaft  41 , with the portion at the outer edge of the pressing member  43  being of a pointed profile. The pawl  40 , by means of the pivot hole  42  entrances at its two ends, is respectively sleeved onto posts  121  and  181  (as shown in FIG. 4) at the interior surface of the main portion  12  of the main member  11  and the main portion  18  of the secondary member  17  and is capable of revolving towards the upper extent of the roller  30  adjacent to the front end of the dispensing body  10 . The pressing member  43  is postured vertically downward and, furthermore, its bottom edge against the circumferential face of the roller  30 . In addition, the pawl  40  has a triangle-shaped engaging portion  45  extending downward from its inner end and. Based on the inclination angle of the pawl  40 , the engaging portion  45  engages a bottom lands between two protrusions  34  (as shown in FIG. 2) of the roller  30  or is disengaged from the outer sides of the protrusions  34  (as shown in FIG. 5). When the pawl  40  is inclined to the rear, it is immobilized by the stop portion  15  of the dispensing body  10  at the position indicated in FIG. 2, at which time the bottom edge of the pressing member  43  enters one of the grooves  33  along the circumferential face of the roller  30  and the engaging portion  45  is correspondingly engaged between two protrusions  34 . In addition, the pressing member  43  has a trip element  46  (as shown in FIG. 4) extending outward from its exterior edge that is visible at the lower extent of the secondary member  17  of the dispensing body  10 .  
         [0016]    An elastic member  50 , which is a torsion spring in this embodiment, is installed at the interior end of the pawl  40  such that its coils are situated around the post  121  of the dispensing body  10  (as shown in FIG. 4) which the pawl  40  is sleeved onto and, furthermore, one of its extremities is postured against the dispensing body  10  and the other extremity is situated against the pawl  40 , with its decompressive force impelling the pawl  40  into a rearward inclination.  
         [0017]    A guide wheel  60  of a cylindrical shape is pivotally mounted between the main portion  12  of the main member  11  and the main portion  18  of the secondary member  17  of the dispensing body  10  and situated in front of the roller  30  and the pawl  40 .  
         [0018]    A blade  70  is mounted on the front end of the dispensing body  10  that has a serrated anterior edge and, furthermore, is positioned parallel to the axis of the guide wheel  60 .  
         [0019]    A blade cover  80  is hinged onto the front end of the dispensing body  10  and situated over the upper extent of the blade  70  that is capable of being folded down and fixed into position, as indicated in FIG. 2, to conceal the cutting edge of the blade  70  as a protective function and capable of being folded up into a fixed position, as indicated in FIG. 2, to expose the blade  70 .  
         [0020]    Given the structure of the adhesive tape dispenser provided by the preferred embodiment of the present invention, the tape cover  20  is first opened before utilization and a roll of tape T is sleeved onto the tubular pivot  13  of the dispensing body  10  carrier portion  13  (after which the tape cover  20  is closed) and, furthermore, tape t is then pulled from the roll of tape T. Thereafter, the trip element  46  of the pawl  40  is actuated, causing the pressing member  43  of the pawl  40  to incline forward such that sufficient clearance is present between its bottom edge and the circumferential face of the roller  30 , following which the tape t is inserted between the pressing member  43  and the roller  30  (Note: Attention must be paid to the winding direction of the roll of tape T such that the adhesive surface of the tape t is at this time facing towards the circumferential face of the roller  30 .) and after the tape t has been correctly inserted, the pawl  40  is released, subjecting the pawl  40  to the rebound force of the elastic member  50  such that the bottom edge of the pressing member  43  lightly presses the tape t against the circumferential face of the roller  30 . Thereafter, the tape t is then pulled out to an adequate length with its surface passing over the circumferential face of the guide wheel  60  up to (or beyond) the anterior edge of the blade  70 .  
         [0021]    When utilizing the adhesive tape dispenser, four fingers are placed within the interior portion of the tubular pivot  13  of the dispensing body  10  and the thumb is positioned against the tape cover  20  such that the dispensing body  10  is held in one hand. During adhesive tape application, the blade cover  80  is folded open to enable the attachment of the tape t onto an object and then the entire tape dispenser is drawn to the rear such that the roll of tape T remains stationary but rotates continuously at its original position (counter-clockwise rotation is depicted in FIG. 2) as the tape t is dispensed. Following the application of an appropriate length, the front end of the tape dispenser is pressed downward and towards the rear to cut the tape t with the blade  70 .  
         [0022]    During the process of adhesive tape application, the roller  30  rotates forward (rotation is counter-clockwise in FIG. 2 and is hereafter referred to as rotation in the same direction) due to the adhesive stick of the tape t and when the roller  30  rotates in the same direction, the protrusions  34  undulate the engaging portion  45  of the pawl  40 , with the relative angle shown in FIG. 2, and the engaging portion  45  is pushed forward by the outer sides of the protrusions  34 , but when the roller  30  then proceeds forward in the same direction of rotation and after a minute angular disposition, since the pawl  40  is pushed backward by the elastic member  50 , the engaging portion  45  then engages in between the next two protrusions  34  and reverts to the relative relationship indicated in FIG. 2 and, as such, the pawl  40  is repeatedly rocked back and forth (Note: The outer sides of the protrusions  34  and end of the engaging portion  45  are of a pointed profile to aid the sliding in and out of the engaging portion  45 .). When the roller  30  is rotated in the same direction, the pawl  40  is accordingly brought forward and disengaged such that the forward delivery of tape t is not affected and the bottom edge of its pressing member  43  presses the tape t evenly against the circumferential face of the roller  30 , thereby maintaining the smooth dispensing of the tape t.  
         [0023]    After the tape t has been cut (specifically, during disuse), a small portion of adhesive tape remains affixed to the circumferential face of the roller  30 , with its unwound rear extent held fast against the tape rest portion  16  of the dispensing body  10  such that the tape t does not attach itself to other objects.  
         [0024]    As previously described, when the pawl  40  is inclined to the rear, it is immobilized by the stop portion  15  and engaged to the roller  30 , with the relative angle shown in FIG. 2. As such, the exerted force causes the backward rotation in the opposite direction of the roller  30  and, due to the relative angle, the protrusions  34  of the roller  30  are engaged by the engaging portion  45  of the pawl  40  and, therefore, the roller  30  is immediately arrested and cannot rotate in the opposite direction. In other words, if the roll of tape T is rotated backwards in the opposite direction due to an unintentional application of external force while the tape dispenser of the present invention being utilized, since the front end of the tape t is affixed onto the roller  30  which is disabled from rotating in the opposite direction in this state (and is also restrained by the pressing member  43 ), rotating the roll of tape T in the reverse direction is difficult and, as a result, the tape t cannot retract and cling to itself.  
         [0025]    As conveyed by the description, the adhesive tape dispenser provided by the present invention effectively prevents the troublesome occurrence of adhesive tape retraction and sticking, thereby enabling ease and convenience during tape application.