Patent Publication Number: US-2017368698-A1

Title: Film cutter

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to cutting tools and, more particularly, to a film cutter. 
     2. Description of the Prior Art 
     A conventional film cutter has a cutting portion that is protruded invariably to cut a tape. Another conventional film cutter has a cutting portion that is protruded and retracted flexibly but inconveniently, and/or actuated slowly, and/or secured unsteadily and imprecisely. 
     Therefore, the aforesaid drawbacks of the conventional film cutters still have room for improvement. 
     SUMMARY OF THE INVENTION 
     In view of the aforesaid drawbacks of the prior art, it is an objective of the present invention to provide a film cutter with a movable knife which is not only protruded and retracted conveniently, quickly but also secured in place firmly, precisely. 
     In order to achieve the above and other objectives, the present invention provides a film cutter which comprises: a body unit having a gripping portion, a receiving portion, a pivotal portion, a sliding portion, an access slit, and a film feeding opening; a movable knife having a pivotal connection portion pivotally disposed at the pivotal portion of the body unit, and a cutting portion; an operating unit having a sliding portion disposed at the sliding portion of the body unit, an operating portion for driving the sliding portion, a knife controlling portion for actuating the movable knife to rotate about the pivotal portion of the body unit and thus allow the cutting portion of the movable knife to be exposed from or to retract into the access slit; two blades disposed in the body unit and each having a sharp edge tilted at an angle relative to and corresponding in position to the film feeding opening; and a guide member mounted on the body unit and corresponding in position to the film feeding opening. 
     Hence, the film cutter of the present invention is characterized in that the movable knife is not only protruded and retracted conveniently, quickly but also operated and changed conveniently due to the pivotal swing-related relationship between the operating unit and the body member. 
     Preferably, the body unit has an operating hole and an operating-positioning portion formed at the operating hole, and the operating portion is slidable within the operating hole and blocked by the operating-positioning portion from two sides. 
     Preferably, the body unit has two sliding-positioning portions, and the operating unit has a positioning portion positioned at each said sliding-positioning portion of the body unit. 
     Preferably, the operating unit has a slide and a cushioning element coupled to the slide, and the knife controlling portion is disposed at the cushioning element. 
     Preferably, the slide has an engaging-protruding portion, and the cushioning element has an engaging hole for fitting around the engaging-protruding portion of the slide. 
     Preferably, the movable knife has a first pressing-swinging portion actuated by the knife controlling portion to allow the cutting portion of the movable knife to retract into the access slit, and a second pressing-swinging portion actuated by the knife controlling portion to swing and thus allow the cutting portion of the movable knife to be exposed from the access slit. 
     Fine structures and features of the film cutter provided by the present invention are described in detail later. However, persons skilled in the art must understand that specific embodiments described below and carried out to implement the present invention are illustrative of the present invention rather than restrictive of the claims of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a film cutter according to a preferred embodiment of the present invention; 
         FIG. 2  is an exploded view of the film cutter according to the preferred embodiment of the present invention; 
         FIG. 3  is another exploded view of the film cutter according to the preferred embodiment of the present invention; 
         FIG. 4  is a cutaway view of the film cutter according to the preferred embodiment of the present invention; 
         FIG. 5  is a cutaway view of the film cutter operating in a mode according to the preferred embodiment of the present invention; and 
         FIG. 6  is a cutaway view of the film cutter operating in another mode according to the preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENT OF THE INVENTION 
     Directional prepositions, such as “on” and “within,” used herein must be interpreted with reference to directions indicated in the diagrams of the present invention. 
     Technical solutions and features of the present invention are hereunder illustrated by embodiments and accompanying drawings and described in detail. 
     Referring to  FIG. 1  through  FIG. 6 , a film cutter according to a preferred embodiment of the present invention comprises a body unit  1 , a movable knife  40 , an operating unit  5 , two blades  70 , and a guide member  80 . 
     The body unit  1  has a body member  10  and a cover member  20  coupled to the body member  10  by a bolt  31  and a nut  32 . 
     The body member  10  has a gripping portion  11 , a receiving portion  12 , a fastening hole  13  which the bolt  31  penetrates, a pivotal portion  14 , a sliding portion  15 , two sliding-positioning portions  153 , an access slit  16 , an operating hole  17 , an operating-positioning portion  171  formed at the operating hole  17 , and a film feeding opening  18 . 
     The cover member  20  has a through hole  231  which the bolt  31  penetrates, a nut hole  232  for holding the nut  32 , a pivotal hole  24  which the pivotal portion  14  is inserted into, a sliding portion  25  corresponding in position to the sliding portion  15 , and a slot  26  disposed on one side of the sliding portion  25 . 
     The movable knife  40  has a pivotal connection portion  41  pivotally disposed at the pivotal portion  14  of the body unit  1 , a first pressing-swinging portion  43 , a second pressing-swinging portion  44 , and a cutting portion  45 . 
     The operating unit  5  has a slide  50  and a cushioning element  60  coupled to the slide  50 . 
     The slide  50  has a sliding portion  51  disposed at the sliding portion  15  of the body unit  1 , an operating portion  52  for connecting with and driving the sliding portion  51 , a positioning portion  53  positioned at each sliding-positioning portion  153  of the body unit  1 , and two engaging-protruding portions  54  disposed on one sides of the sliding portion  51 . 
     The operating portion  52  is slidable within the operating hole  17  and blocked by the operating-positioning portion  171  from two sides. 
     Both the operating-positioning portion  171  and the positioning portion  53  are each hollowed out on the other side, so as to be deformable and movable. 
     The cushioning element  60  has an engaging portion  61  which abuts against the sliding portion  51  of the slide  50 , two engaging holes  62  for fitting around the engaging-protruding portions  54  of the slide  50 , a knife controlling portion  63  for actuating the movable knife  40  to rotate about the pivotal portion  14  of the body unit  1  and thus allow the cutting portion  45  of the movable knife  40  to be exposed from or to retract into the access slit  16 . 
     The knife controlling portion  63  actuates the first pressing-swinging portion  43  of the movable knife  40  to allow the cutting portion  45  of the movable knife  40  to retract into the access slit  16 . The knife controlling portion  63  actuates the second pressing-swinging portion  44  of the movable knife  40  to swing and thus allow the cutting portion  45  of the movable knife  40  to be exposed from the access slit  16 . 
     The two blades  70  are disposed in the body member  10  and each have a sharp edge  72  corresponding in position to the film feeding opening  18 . 
     The guide member  80  is mounted on the body unit  1  and corresponds in position to the film feeding opening  18 . 
     The cushioning element  60  not only enables the movable knife  40  to slide and press on better but also reduces the wear and tear of the slide  50  and thus renders it durable. 
     The first pressing-swinging portion  43  of the movable knife  40  flanks the pivotal connection portion  41  and presses against the knife controlling portion  63  of the cushioning element  60 ; hence, the first pressing-swinging portion  43  enables the movable knife  40  to swing and rotate steadily without vibrating. 
     Therefore, the film cutter of the present invention is characterized in that the movable knife  40  is not only protruded and retracted conveniently, quickly but also secured firmly, precisely. Hence, the embodiment achieves the objectives of the present invention. 
     In addition to the aforesaid embodiment, the present invention may be implemented according to a variant embodiment as follows: 
     For instance, the body unit  1  does not necessarily consist of the aforesaid two members, namely the body member  10  and the cover member  20 , and thus the body unit  1  may be provided in the form of a single member. 
     Alternatively, the operating unit  5  does not necessarily have the cushioning element  60 , and the knife controlling portion  63  is formed from the slide  50 . 
     The aforesaid embodiments, either separately or jointly, achieve the objectives of the present invention. 
     In conclusion, the film cutter of the present invention is characterized in that the movable knife  40  is not only protruded and retracted conveniently, quickly but also secured firmly, precisely, thereby achieving the objectives of the present invention.