Cutter

A cutter can rapidly and safely cut the edge of a variety of paper products and a variety of strings and other materials used for packaging. The cutter has a pair of holders laminated to each other, a pair of open-close bodies which are rotatably supported at edge portions of the holders, respectively and form a cutting area through which a paper product can be passed, and a cutting blade which is mounted to the edge portions of the holders and has a cutting edge protruding into the cutting area.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a cutter, and more specifically, to a cutter 
which can efficiently open an envelope, cut the edge of a paper carton for 
milk, juice or other beverages, or that of a corrugated box or like 
member, and which can cut a variety of strings, tapes, and other materials 
used for packaging. 
2. Description of the Related Art 
Conventionally, as a means for cutting the edge of an envelope, a paper 
carton, and the like, or as a means for cutting strings, tapes, and other 
materials used for packaging, a knife and scissors are well known. 
However, when a knife is used, for example, to cut the edge of an envelope, 
the cutting edge of the blade of the knife must be inserted inside the 
edge of the envelope. Thus, the envelope cannot be rapidly cut. In 
addition, the blade of the knife is exposed during the cutting operation. 
Thus, one's finger could be cut. 
On the other hand, when a pair of scissors is used to cut the edge of an 
envelope or paper carton, the scissors must be opened and closed many 
times. Thus, the envelope cannot be rapidly cut. 
Also when cutting various types of strings, tapes, and other materials 
which are used for packaging, the same problems as those state above are 
presented. 
SUMMARY OF THE INVENTION 
In consideration of the above-stated problem, an object of the invention is 
to provide a cutter which can rapidly and safely cut the edge of a variety 
of paper articles, and which can cut various types of string and other 
materials used for packaging. 
The cutter of this invention has a pair of holders laminated to each other; 
a pair of open-close bodies which are rotatably supported at the edge 
portion of the holders and form the cutting area through which the portion 
of the workpiece, such as a piece of paper or overlapped or box-like 
member, to be cut can be passed; and a cutting blade which is mounted to 
the holders with a cutting edge thereof located in the cutting area. 
The pair of holders include a pair of plates which are joined to the 
open-close bodies and which can be flexed to rotate the respective 
open-close bodies. Alternatively, the holder and the open-close bodies can 
be molded integrally. 
In addition, a pair of holding-down pieces are provided on the pair of 
open-close bodies to center the article to be cut relative to the cutting 
blade. 
A groove is defined between the holders and the open-close bodies where the 
cutting edge of the cutting blade is located, and into which groove string 
or other material can be inserted for cutting. A slider for chip removal 
is disposed in a recess extending into the holders from the vicinity of 
the cutting edge of the cutting blade. One end of the slider is near the 
cutting edge of the cutting blade and a finger applying protrusion is 
formed at the other end of the slider. The protrusion is exposed at the 
outer surface of one of the holders. Chips can be removed by sliding the 
slider in the groove. 
In addition, a cutting blade replacing member has a small protrusion 
received in a small hole in the bottom of the cutting blade, and a 
push-button exposed at the outer surface of one of the holders. The small 
protrusion is moved down by depressing the push-button protrusion 
resulting in the small protrusion moving out of the small hole in the 
cutting blade. 
A pair of magnets are mounted to the open-close bodies with the N and S 
poles of the magnets being opposed.

DETAILED DESCRIPTION OF THE INVENTION 
The cutter 1, as shown in FIGS. 1 to 5, is provided with a pair of holders 
5 and 6 which include parallelepipedal main bodies made of plastic, and 
laminated to each other via a pair of thin plates 3 and 4 which are made 
of, for example, plastic. The thin plates 3 and 4 can bend at an 
appropriate location on the inner of the holders 5, 6. A pair of 
open-close bodies 10 and 11 are mounted to the holders 5 and 6 by being 
rotatably supported by the pair of plates 3 and 4. The open-close bodies 
10 and 11 form a cutting area 9 through which the edge of an envelope 7, a 
paper carton 8 for containing a beverage, or other member to be cut can be 
passed. A cutting blade 12 is mounted at the edge portion of the holders 5 
and 6 so that the cutting edge is in the cutting area 9. 
The pair of plates 3 and 4 are joined to the holders 5, 6, respectively, 
with rivets 16 or other fasteners. One plate 3 can be flexed at the 
boundary between the holder 5 and the open-close body 10, while the other 
plate 4 can be flexed at the boundary between the holder 6 and the 
open-close body 11. 
Alternatively, the pair of holders 5 and 6, open-close bodies 10 and 11, 
and plates 3 and 4 may be molded integrally. Also, a hinge mechanism can 
be provided at the boundary between the holders 5 and 6 and the open-close 
bodies 10 and 11 to rotatably support the open-close bodies 10 and 11, 
instead of the plates 3 and 4. 
One holder 5 and open-close body 10 are provided with surfaces 5a and 10a 
chamfered at an angle of 45 deg or larger in the boundary area, 
respectively, so that the open-close body 10 can be rotated through a 
maximum angle of 90 deg or larger with respect to the holder 5. 
The other holder 6 and open-close body 11 are also provided with the 
surfaces 6a and 11a chamfered at an angle of 45 deg or larger in the 
boundary area, respectively, so that the open-close body 11 can be rotated 
through a maximum angle of 90 deg or larger with respect to the holder 6. 
Cutout portions 10b and 11b at respective ends of the open-close bodies, 
respectively, guide the envelope 7 or other member through the cutter. In 
addition, the open-close bodies 10 and 11 are provided with the 
holding-down pieces 17 and 18 to hold down the envelope 7 or other member 
at opposite positions. A slight clearance is maintained between the 
holding-down pieces 17 and 18 when the open-close bodies 10 and 11 are 
kept closed with a pair of magnets 13 and 14 attracting each other as 
shown in FIG. 3. The holding-down pieces 17 and 18 are convenient to 
center the envelope 7 or other workpiece when cutting the edge thereof, 
and to hold down the workpiece so that the cutting edge of the cutting 
blade 12 is positioned at the center with respect to the workpiece when 
the edge of a piece of paper or overlapped piece of paper is to be cut 
while the pair of open-close bodies 10 and 11 are closed. 
The pair of magnets (permanent magnets) 13 and 14 is provided near the 
cutting area 9 with the N and S poles thereof being opposed. A recess 31 
extends within the holders 5 and 6 from the vicinity of the cutting edge 
of the said cutting blade 12. A slider 34 for chip removal can be slid in 
this recess in the directions of the arrow in FIG. 4. One end 32 of the 
slider is near the cutting edge of the cutting blade 12, and a finger 
applying protrusion 33 formed at the other end of the slider is exposed at 
the outer surface of either one of the holders. Reference numeral 34a in 
FIG. 4 denotes a leaf spring which is provided to return the said slider 
34 to its original position. 
A groove portion 35, in which a workpiece string or other member can be 
inserted, is provided in the area between the holders 5 and 6 and the 
open-close bodies 10 and 11, where the cutting edge of the cutting blade 
12 is located. A cutting blade replacing member 39, in the pair of holders 
5 and 6, has a small protrusion 36 at one end received in a small hole 37 
in the bottom of the cutting blade 12 and a push-button protrusion 38 at 
the other end exposed at the outer surface of one of the pair of holders 5 
and 6. The small protrusion 36 is moved down by depressing the push-button 
protrusion 38 as shown with the arrows in FIG. 5, resulting in the small 
protrusion 36 being moved out of the small hole 37 in the cutting blade 
12. 
Now, the operation of the cutter 1 when the edge of a paper workpiece, such 
as an envelope 7, a paper carton 8 or other member, is cut will be 
described. 
First, when cutting the edge of an envelope 7 or other piece of paper, the 
pair of open-close bodies 10 and 11 which are rotatably supported at the 
edges of the pair of holders 5 and 6 in this cutter 1, respectively, is 
closed to form a thin cutting area 9 corresponding to the shape of the 
envelope 7, as shown in FIG. 6. The edge of the envelope 7 is rapidly 
passed through the thin cutting area 9 formed by the pair of open-close 
bodies 10 and 11 in the direction of the arrow as shown in FIG. 7. In this 
operation, the edge of the envelope 7 is held down and centered by the 
holding-down pieces 17 and 18 at both sides of the envelope. Thus, the 
edge of the envelope 7 is moved accurately along the cutting blade 12 
mounted at the edges of the holders 5 and 6, resulting in that the edge of 
the envelope 7 is continuously cut. Thus, the edge of the envelope is cut 
as shown in FIG. 8. 
The slider 34 is slid in the groove 31 by urging the protrusion 33 with a 
finger toward the cutting edge of the cutting blade 12 to bring the end 32 
of the slider 34 opposite the finger applying protrusion 33 to the outside 
of the holders 5 and 6, resulting in the chips produced during cutting and 
accumulated near the cutting edge of the cutting blade 12 being discharged 
to the outside of the holders 5 and 6. 
Next, when cutting the corner of a paper box 8 or other member, the pair of 
open-close bodies 10 and 11 which are rotatably supported at the edges of 
the pair of holders 5 and 6 in this cutter 1, respectively, is opened to 
form an enlarged, open cutting area 9 corresponding to the shape of the 
paper box 8 to be cut, as shown in FIG. 9. 
Then, the corner of the paper box 8 that offers an angle of approximately 
90 deg is rapidly passed along the cutting blade 12 which protrudes into 
the enlarged, open cutting area 9 as shown in FIG. 10. This results in the 
edge of the paper box 8 being continuously cut. Thus, the corner of the 
paper box 8 is cut as shown in FIG. 11. 
By repeating such an operation on the corners of a paper box 8 or like 
member, the paper box 8 can then easily be flattened. The corners of a 
corrugated box can also be cut so that it can be flattened out in the same 
way as stated above. 
When the cutter 1 of this embodiment is used to cut a variety of strings, 
tapes and other materials which are employed for packaging, such as those 
constituting a corrugated box, the open-close bodies 10 and 11 are fully 
opened. With the cutting blade exposed in this state, a string or other 
piece of material can be cut easily. A string or other piece of material 
can also be easily cut with the cutter 1 by inserting the string or the 
like into the groove portion 35 provided in the area between the holders 5 
and 6 and the open-close bodies 10 and 11, and using the cutting edge of 
the cutting blade 12 that is located in the deepest area of the grooved 
portion 35. 
Thus, the cutter 1 of this embodiment can rapidly and safely cut the edge 
of an envelope, a paper carton or like member, or can cut a string or 
other material with high efficiency. 
The cutting blade replacing member 39 for use in replacement of the cutting 
blade 12 is provided inside of the pair of holders 5 and 6. Depressing the 
push-button protrusion 38 of the cutting blade replacing member 39 with 
one's finger moves the small protrusion 36 from the small hole 37 in the 
bottom of the cutting blade 12. Thus, the cutting blade 12 can be replaced 
in this state. Then, by releasing the push-button protrusion 38, the new 
cutting blade is secured in the holders. 
When the cutter 1 is not in use, the pair of magnets 13 and 14 mounted to 
the open-close bodies near the cutting area are attracted to each other to 
fix the open-close bodies in a parallel arrangement, which makes the 
cutter 1 compact and safe. 
This invention is not limited to the above-described embodiment, but 
various other embodiments within the scope of the claims will be readily 
apparent to those of ordinary skill in the art.