Abstract:
A hand held rotary cutter comprising a first handle including a head at one end thereof for receiving a blade and a second handle pivotally connected to the first handle. The second handle includes a rotating member at one end thereof. The rotating member rotates into and out of alignment with the head of the first handle to guard the blade. A spring biases the first and second handles to an open position, and a latch is mounted on one of the first and second handles and movable between an unlocked position and a locked position. The latch is engageable with a member on the other of the first and second handles. When the latch is in the unlocked position, the first handle and the second handle are fixed in position relative to each other.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention is directed to cutting tools. More particularly, the present invention is related to a hand-held rotary cutting tool that is simple to use and incorporates an easily replaceable cutting edge.  
         BACKGROUND OF THE INVENTION  
         [0002]    Hand-held rotary cutting tools are conventionally known. Such rotary cutters are of particular utility for cutting sheet material such as cloth and wallpaper. Rotary cutters often comprise an elongated handle with a circular cutting blade rotatably fastened to one end. The user grasps the handle and rolls the circular cutting blade along the object to be cut, while placing downward and forward pressure on the cutting wheel. Guard mechanisms to cover or otherwise limit access to the blade when the rotary cutter is not in use are also conventionally known.  
           [0003]    Many prior art hand-held rotary cutters tend to have a number of disadvantages. For example, some hand-held rotary cutting tools tend to be uncomfortable and difficult to guide accurately when exerting sufficient downward and forward force to effect cutting. Additionally, several conventional cutting tools include guard mechanisms which are cumbersome in how the blade is to be exposed and retracted. Other conventional cutting tools are not equally capable of use with either a right or a left hand. A number of portable rotary cutters do not include any mechanism for fixing the handles in either a closed position or an open position. Furthermore, a number of rotary cutters include several components which make the cutter relatively expensive to manufacture.  
         SUMMARY OF THE INVENTION  
         [0004]    It is therefore an object of the invention to provide an improved rotary cutting tool that can be fixed in either an open position or a closed position.  
           [0005]    It is another object of the invention to provide an improved rotary cutting tool that includes a simple mechanism for removing and replacing a cutting edge.  
           [0006]    It is yet another object of the present invention to provide an improved rotary cutting tool that is inexpensive to manufacture.  
           [0007]    It is still another object of the invention to provide an improved rotary cutting tool that can be more easily used by both right-handed and left-handed individuals.  
           [0008]    It is another object of the invention to provide an improved rotary cutting tool that increases the exposure of the blade during cutting while maintaining an adequate level of safety.  
           [0009]    It is finally another object of the present invention to provide an improved rotary cutting tool that permits a blade to be replaced without the use of additional tools.  
           [0010]    In accordance with the above objects, a rotary cutting tool comprises a first handle including a head at one end thereof for receiving a blade, the head having a transverse member upon which a blade may be mounted. A second handle is pivotally connected to the first handle and includes a blade guard. The blade guard is capable of moving into and out of alignment with the head. A biasing member biases the first and second handles away from each other to an open position. A latch is mounted on the second handle and is movable between a first position and a locked position. The latch is engageable with a coupling member on the first handle. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    The foregoing advantages and features of the invention will become apparent upon reference to the following detailed description and the accompanying drawings, of which:  
         [0012]    [0012]FIG. 1 is a perspective view of a rotary cutting device in an open position according to one embodiment of the invention;  
         [0013]    [0013]FIG. 2 is a side view of the rotary cutting device of FIG. 1 in the open position;  
         [0014]    [0014]FIG. 3 is a side view of the rotary cutting device of FIG. 1 in the closed position;  
         [0015]    [0015]FIG. 4 is an opposite side view of the rotary cutting device of FIG. 1 with the blade guard in an open position;  
         [0016]    [0016]FIG. 5 is an exploded side view of the cutting device of FIG. 1;  
         [0017]    [0017]FIG. 6 is a sectional side view of the cutting device of FIG. 1 when in an open and unlatched position;  
         [0018]    [0018]FIG. 7 is a sectional side view of the cutting device of FIG. 1 when in a closed and unlocked position;  
         [0019]    [0019]FIG. 8 is a magnified sectional view of the latching mechanism of the cutting device when in a locked position;  
         [0020]    [0020]FIG. 9 is a sectional view of the latching mechanism taken along lines  9 - 9  of FIG. 8;  
         [0021]    [0021]FIG. 10 is a sectional side view of the cutting device of FIG. 1 when in an open and locked position;  
         [0022]    [0022]FIG. 11 is a sectional side view of the cutting device of FIG. 1 when in the closed and locked position; and  
         [0023]    [0023]FIG. 12 is a segmented perspective view of the cutting device of FIG. 1 with the cap removed. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0024]    Referring to FIGS. 1, 2,  6  and  7 , a rotary cutting device is shown generally at  10 . The rotary cutting device  10  includes a first handle  12  and a second handle  14 . The first handle  12  and the second handle  14  are pivotally connected to each other by a screw  16 . Other types of connecting devices, such as pins, nails, rivets or similar mechanisms, can also be used as an adequate and functional pivoting device.  
         [0025]    The first handle  12  includes a lower portion  13  which defines a slot  18  through which the user can place his or her hand. The slot  18  defined by the lower portion  13  of the first handle  12  provides the user with an additional amount of control of the cutting device  10 . In a preferred embodiment of the invention, the first handle  12  and the second handle  14  are shaped such that a user can use the rotary cutting device  10  in a proficient matter whether he is right-handed or left-handed.  
         [0026]    As shown in FIG. 5, the first handle  12  includes a head portion  20  at one end thereof. The head portion  20  includes a transverse member  22  which projects at about a ninety degree angle from the rest of the head portion  20 . The transverse member  22  is sized such that a cutting blade  24  can be placed around the transverse member  22 . The cutting blade  24  is secured on the transverse member  22  by a cap  26 . In one preferred embodiment of the invention and as shown in FIG. 12, the cap  26  is secured to the transverse member  22  by a plurality of threads  28 . It is possible, however, that any one of a variety of security mechanisms could be used to secure the cap  26  to the transverse member  22 . For example, the cap  26  could be snap fit onto the transverse member  22 .  
         [0027]    As shown in FIGS.  4 - 5 , the second handle  14  includes a blade guard  30  rotatably coupled thereto at a top portion  32 . The blade guard  30  serves to protect the user from inadvertently injuring his or her hand on the cutting blade  24  when it is positioned within the cutting device  10 . The blade guard  30  includes a slot  34  through which the transverse member  22  may be positioned. This permits the blade guard  30  to be placed in substantial alignment with the head portion  20 . While the blade  24  is positioned on the transverse member  22 , the transverse member  22  projects through the slot  34  and the cap  26  threadedly engages the transverse member  22 .  
         [0028]    In one embodiment of the invention and as shown in FIG. 4, the second handle  14  also includes an abutment  36  adjacent to and substantially coplanar with the head portion  20  of the first handle  12 . The abutment  36  serves to impede the motion of the first handle  12  relative to the second handle  14 , effectively preventing the first handle  12  from moving too far away from the second handle  14 .  
         [0029]    The first handle  12  includes an inner side  46  and an outer side  48 . Similarly, the second handle  14  includes an inner side  56  and an outer side  58 . During the pivoting motion of the first handle  12  and the second handle  14  relative to each other, the inner side  46  of the first handle  12 , in one embodiment of the invention, comes into contact with the inner side  56  of the second handle  14 .  
         [0030]    As shown in FIGS.  6 - 11 , the inner side  46  of the first handle  12  includes leaf spring  40 . The leaf spring  40  is engaged by a contact member  42  that is coupled to the inner side  56  of the second handle  14 . In one preferred embodiment of the invention, the contact member  42  is formed as one piece with the second handle  14  and projects at an angle from the inner side  56  of the second handle  14  towards the inner side  46  of the first handle  12 . In a most preferred embodiment of the invention, the leaf spring  40  and the contact number  42  are positioned such that they are in substantially constant engagement with each other. The engagement of the contact member  42  with the leaf spring  40  results in a biasing action, in which the second handle  14  is biased away from the first handle  12 , biasing the rotary cutting device  10  towards an open position.  
         [0031]    In one embodiment of the invention, the first handle  12  also includes a latch  50  that is movable between an unlocked position  70  and a locked position  72 . This is shown clearly in FIG. 8. In a most preferred embodiment of the invention, the latch  50  is located on the outer side  48  of the first handle  12 , although it is possible for the latch  50  to be located in a different position on the first handle  12  or the second handle  14 . The latch  50  is coupled to a blocking member  52  that is positioned inside the inner side  46  of the first handle  12 . The latch  50  and the blocking member  52  are arranged such that the first handle  12  and the second handle  14  can be locked in position relative to each other, fixing the rotary cutting device  10  in both an open position and a closed position.  
         [0032]    When the latch  50  is in the unlocked position  70 , shown for example in FIGS. 5 and 7, the first handle  12  and the second handle  14  are free to move towards each other and away from each other. When the latch  50  is in the unlocked position  70 , the blocking member  52  does not contact a latching member  54  that is formed on the inner side  56  of the second handle  14 . By maintaining the blocking member  52  in this position, the latching member  54 , and the entire second handle  14  is capable of moving back and forth relative to the first handle  12 .  
         [0033]    When the latch  50  is moved to a locked position  72  the blocking member  52  is positioned to interfere with the latching member  54 . This interference occurs regardless of whether or not the second handle  14  is in contact with the first handle  12 . In the case where the rotary cutting device  10  is in an open position (i.e., the first handle  12  and the second handle  14  are separated), the latching member  54  comes into direct contact with and abuts the blocking member  52 . This positioning prevents the second handle  14  from moving closer to the first handle  12 . When the rotary cutting device  10  is in the closed position (i.e., the first handle  12  and the second handle  14  are in contact with each other), the latching member  54  is located partially within the inner side  56  of the second handle  14 . The latching member  54  also latches onto the blocking member  52  by use of a hook  55 , fixing the position of the second handle  14  relative to the first handle  12 .  
         [0034]    In a preferred embodiment of the invention the first handle  12 , the second handle  14 , the latch  50  and the blade guard  30  are all formed from a multiple plastic material, while the transverse member  22  is formed from a metal. It is possible, however, for the individual components to be formed from a variety of materials, depending upon the particular cost, durability and quality considerations.  
         [0035]    As shown in FIGS.  3 - 4 , the rotary cutting device  10  includes a front side  80  and a back side  82 . In a preferred embodiment of the invention, the front side  80  includes the blade guard  30  thereon. In a most preferred embodiment of the invention, the back side  82  of the rotary cutting device  10  exposes the cutting blade  24  to a much larger degree than the front side  80  of the rotary cutting device  10 . The increased exposure of the cutting blade  24  permits the user to use the rotary cutting device  10  in conjunction with an acrylic quilting ruler or straightedge (not shown). The use of such an acrylic quilting ruler, which typically has a thickness of about 0.125 inches, aids the user in cutting along a straight line.  
         [0036]    During the operation of the rotary cutting device  10 , a portion of the cutting blade  24  is completely exposed when the first handle  12  and the second handle  14  are brought towards each other. In a preferred embodiment of the invention and as shown in FIG. 3, a relatively large portion of the cutting blade  24  is exposed during cutting, aiding the user in accurately cutting the material in question.  
         [0037]    It should be understood that the above description of the invention and specific examples and embodiments, while indicating the preferred embodiments of the present invention, are given by demonstration and not limitation. For example, it is possible that components such as the blade guard  30 , the head portion  20  and the latch  50  could be placed on the other of the first handle and the second handle, depending upon the particular requirements of the customer. Additionally, a variety of different devices can be used to secure the blade  24  onto the transverse member  22 . Alternatively, it may be possible to secure the blade  24  to the head portion  20  without any transverse member at all. Many changes and modifications within the scope of the present invention may therefore be made without departing from the spirit thereof and the present invention includes all such changes and modifications.