Plastic knife

Abstract

To provide a plastic knife which is excellent in safety and enables easy discard.SOLUTION: A substrate 2 is a plate-like member which is composed of a synthetic resin forming fine unevenness on a split surface, and has a predetermined thickness. A first inclined surface part 3 constitutes a predetermined inclined surface by being cut into an L shape in cross-sectional view with a thickness thinner than a thickness of the substrate 2, along a first straight line 6. An opening 4 is configured by opening a triangle whose one side coincides with the first straight line 6 on an inclined surface of the first inclined surface part 3. A second inclined surface part 5 constitutes a predetermined inclined surface on the substrate 2 on a side of the first inclined surface part 3 by being cut into an L shape in cross-sectional view with a thickness thinner than the thickness of the substrate 2, along a second straight line 7 forming a predetermined sharp angle with respect to the first straight line 6. The substrate 2 is broken along the first straight line 6, and the substrate 2 is broken along the second straight line 7, and thereby the triangle of the opening 4 and the inclined surface are used as a saw blade 4a with the one end of the substrate 2 as a blade tip.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a plastic knife. [Background technology]

[0002] There are many conventional techniques for cutter knives, such as metal cutter knives, plastic cutter knives, and card-type cutter knives. For example, Japanese Utility Model Application Publication No. 52-033568 (Patent Document 1) discloses a plastic fruit knife in which a blade is formed on a plastic knife base material and the blade surface is molded into an angled surface that fits the outer peripheral surface of a fruit. This makes it possible to provide a plastic fruit knife that is easy to peel fruits such as apples and pears, is easy to use, inexpensive, disposable, and has a blade that can be easily sharpened with sandpaper or the like.

[0003] Japanese Utility Model Application Laid-Open Publication No. 01-092973 (Patent Document 2) discloses a card-type knife in which a thin cutting blade is bendably provided on a part of a thin base body on almost the same plane as the thin base body, and the cutting blade body is surrounded by the thin base body. This makes it possible to provide a novel card-type knife that is not bulky, lightweight, and does not require high dimensional accuracy, a precise fitting structure, a moderate degree of rotation, etc. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Utility Model Application Publication No. 52-033568 [Patent Document 2] Japanese Utility Model Application Publication No. 01-092973 Summary of the Invention [Problem to be solved by the invention]

[0005] Currently, the Internet shopping market is expanding, and the number of opportunities to receive products packed in cardboard boxes is increasing. When a user receives a product and opens the cardboard box, the user generally uses a cutter to cut the packaging tape attached to the cardboard box.

[0006] Here, most cutters are made of metal, and simple cutters usually have an exposed blade regardless of the material. Therefore, if such cutters are always kept at the entrance of the house, there is a problem that they are dangerous to handle. Also, if a user repeatedly uses a cutter and the blade chips, the user puts the blade directly into a garbage bag and discards it. This causes a problem that the cutter blade breaks through the garbage bag, scattering the garbage inside the bag or injuring the person collecting the garbage bag.

[0007] The techniques described in the above-mentioned Patent Documents 1 and 2 cannot solve the above-mentioned problems. The technique described in Patent Document 1 is made of plastic and is intended for peeling fruit, but the sharp blade is exposed. Also, the technique described in Patent Document 2 exposes the cutting blade. Therefore, both techniques have the same problems as those described above.

[0008] SUMMARY OF THE PRESENT DISCLOSURE The present invention has been made to solve the above problems, and has an object to provide a plastic knife that is safe and can be easily disposed of. [Means for solving the problem]

[0009] The plastic knife according to the present invention comprises a substrate, a first inclined surface portion, an opening, and a second inclined surface portion. The substrate is a plate-shaped member having a predetermined thickness and made of a rigid resin that generates fine irregularities on the cutting surface when it is cut. The first inclined surface portion is cut from one end of the substrate along a first straight line on the substrate at a thickness thinner than the thickness of the substrate, forming a V-shaped cross section to form a predetermined inclined surface. The opening portion is formed by opening a triangle, one side of which coincides with the first straight line, on the inclined surface of the first inclined surface portion near one end of the substrate. The second inclined surface portion is cut from one end of the substrate along a second straight line that forms a predetermined acute angle with the first straight line on the substrate on the first inclined surface portion side at a thickness thinner than the thickness of the substrate, forming a V-shaped cross section to form a predetermined inclined surface. The plastic knife of the present invention splits the substrate along the first straight line and then splits the substrate along the second straight line, thereby forming one end of the substrate into a cutting edge and forming the triangle of the opening and the opened inclined surface into a saw blade. Effect of the Invention

[0010] According to the present invention, it is possible to achieve excellent safety and easy disposal. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a plan view showing an example of a plastic knife according to the present invention. [Diagram 2] FIG. 1 is a perspective view showing an example of a plastic knife according to the present invention. [Diagram 3] 3A and 3B are a plan view and a cross-sectional view, respectively, showing the state of a plastic knife according to the present invention before and after a substrate is split along a first straight line. [Figure 4] 1A to 1C are front views showing two examples of plastic knives of the present invention, each having a different color. [Diagram 5] FIG. 5A is a plan view showing a state in which a substrate is split along a first straight line, and FIG. 5B is a plan view showing a state in which the substrate is split along the first straight line and a second straight line. [Figure 6] FIG. 6A is an enlarged view showing an example of the tip of a plastic knife after splitting a substrate along a first line and a second line, and FIG. 6B is an oblique view showing an example of how a plastic knife according to the present invention is used to cut a packaging tape. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings to help the understanding of the present invention. Note that the following embodiment is an example of the present invention and is not intended to limit the technical scope of the present invention.

[0013] The plastic knife 1 according to the present invention comprises a base plate 2, a first inclined surface portion 3, an opening 4 and a second inclined surface portion 5.

[0014] The substrate 2 is a plate-like member having a predetermined thickness and made of a rigid resin that creates fine irregularities on the cut surface when broken. Rigid resin means a resin that has a certain rigidity, and can be broken without bending when a certain force is applied. On the other hand, soft resins that cannot be broken cannot be used in the present invention, and for example, ABS (acrylonitrile-butadiene-styrene) resin cannot be used.

[0015] Here, the type of rigid resin is not particularly limited, but examples thereof include polystyrene resin, etc. The shape of the substrate 2 is not particularly limited, but examples thereof include a rectangle as shown in Fig. 1, a polygon such as a triangle, a square, a rectangle, or a hexagon, a circle, an ellipse, etc.

[0016] The first inclined surface portion 3 is cut in a L-shape in cross section from one end of the substrate 2 along a first straight line on the substrate 2, with a thickness thinner than the thickness of the substrate 2, thereby forming a predetermined inclined surface.

[0017] Here, the thickness of the first inclined surface portion 3 is not particularly limited, but may be, for example, 1 / 6 to 1 / 2 of the thickness of the substrate 2. The angle of the inclined surface of the first inclined surface portion 3 is not particularly limited, but may be, for example, 10 degrees to 45 degrees with respect to the horizontal plane of the substrate 2. This allows a user to easily split the substrate 2 along the first straight line by hand to expose the first inclined surface portion 3, as shown in FIG. 3. Then, fine irregularities that easily function as a blade are generated on the split surface of the first inclined surface portion 3, and the inclined surface of the first inclined surface portion 3 can be made to have a blade-like shape to cut the object to be cut.

[0018] Furthermore, there is no particular limitation on the position of the first straight line 6. For example, when the substrate 2 is rectangular as shown in FIG. 1, the first straight line 6 may be approximately the center line of the long side of the rectangle, may be approximately the center line of the short side of the rectangle, or may be a straight line slightly shifted to either side.

[0019] Here, as shown in Fig. 1, the first inclined surface portions 3 may be provided at two positions on the first straight line 6 that are rotationally symmetrical with respect to the center point of the first straight line 6. This allows the user to create two plastic knives having the first inclined surface portions 3 from one substrate 2 by dividing the substrate 2 along the first straight line 6, as shown in Fig. 3.

[0020] The opening 4 is formed by opening a triangle, one side of which coincides with the first straight line, on the inclined surface of the first inclined surface portion 3 near one end of the substrate 2. The shape of the triangle is not particularly limited, and examples thereof include an equilateral triangle, a right-angled triangle, and an isosceles triangle. The number of triangles is not particularly limited, and may be, for example, 2 to 5. As a result, as shown in FIG. 3, when the user breaks the substrate 2 along the first straight line, the triangle of the opening 4 and the inclined surface of the first inclined surface portion 3 form a saw blade 4a, and a function of cutting the object to be cut with the saw blade 4a can be added.

[0021] In particular, due to the presence of the triangle in the opening 4, by applying a certain force to the minute irregularities of the split surface of the inclined surface of the first inclined surface portion 3, it functions like a sharp blade and can cut the object to be cut. On the other hand, if a certain force is not applied, it is just a split surface of a rigid resin and does not have the sharpness of a normal blade. Therefore, even if a child or elderly person touches it, it will not cut and can be handled safely.

[0022] 1, the openings 5 ​​may be provided at two positions on the first straight line 6 that are rotationally symmetrical with respect to the center point of the first straight line 6. This allows the user to create two plastic knives with saw blades 4a from one substrate 2 by dividing the substrate 2 along the first straight line 6, as shown in FIG.

[0023] The second inclined surface portion 5 is cut from one end of the substrate 2 on the first inclined surface portion 3 side of the substrate along a second straight line that forms a predetermined acute angle with the first straight line, with a thickness thinner than the thickness of the substrate 2, into a L-shape in cross section, thereby forming a predetermined inclined surface.

[0024] Here, the acute angle between the first straight line and the second straight line is not particularly limited, but may be, for example, 10 degrees to 60 degrees. In addition, the thickness of the second inclined surface portion 5 is not particularly limited, but may be, for example, 1 / 6 to 1 / 2 of the thickness of the substrate 2.

[0025] Also, the angle of the inclined surface of the second inclined surface portion 6 is not particularly limited, but can be 10 degrees to 45 degrees with respect to the horizontal plane of the substrate 2. This allows the user to easily split the substrate 2 along the second straight line by hand to expose the second inclined surface portion 6. Also, the split surface of the split first inclined surface portion 3 has fine irregularities that easily function as a blade. Then, the first inclined surface portion 3 and the second inclined surface portion 6 form an acute angle, forming a cutting edge 8, and the user can more easily cut the object by bringing the cutting edge 8 into contact with the object.

[0026] In particular, in the present invention, the minute irregularities on the cutting surface of the rigid resin are effectively utilized to create a blade, and therefore the blade will not function as a blade unless a certain force is applied. Therefore, if the blade loses its sharpness, it can be disposed of as combustible waste even if it is simply placed in a garbage bag, and the plastic knife 1 of the present invention will not break through the garbage bag, causing garbage to scatter and preventing injury to garbage bag collectors.

[0027] 1, the second inclined surface portions 6 may be provided at two positions on the substrate 2 that are rotationally symmetrical with respect to the center point of the substrate 2. This allows the user to create two plastic knives 1 having the second inclined surface portions 6 from one substrate 2 by dividing the substrate 2 along the first straight line 6.

[0028] Now, the effects of the present invention will be described. Figure 4 is a front view showing two examples of the plastic knife 1 according to the present invention, which are different in color. The plastic knife 1 is made of polystyrene resin, which is a rigid resin, and can be designed in different colors.

[0029] As shown in Figure 5, a user takes plastic knife 1, and uses one end of substrate 2 defined by first inclined surface portion 3 and second inclined surface portion 5 as cutting edge 8, and uses the triangle of opening 4 and the inclined surface of first inclined surface portion 3 as saw blade 4a, brings these into contact with packaging tape or the like, and applies a certain force, thereby being able to cut the packaging tape or the like.

[0030] Furthermore, in the present invention, if the plastic knife 1 is made of a soft resin such as ABS resin, even if it is broken, no cracked surface or fine irregularities will be created because the soft resin itself is viscous, and the effect of the present invention will not be achieved. [Industrial Applicability]

[0031] As described above, the plastic knife according to the present invention is effective as a plastic knife that is highly safe and can be easily disposed of. [Explanation of symbols]

[0032] 1 plastic knife 2. Board 3. First inclined surface portion 4 Openings 4a Saw blade 5 Second inclined surface portion 6. First Straight Line 7 Second Line 8 Cutting Edge

Claims

[Claim 1] a substrate, which is a plate-like member having a predetermined thickness and made of synthetic resin that has fine irregularities on the split surface when split; a first inclined surface portion that is cut from one end of the substrate along a first straight line on the substrate to a thickness thinner than the thickness of the substrate and that has a L-shape in a cross-sectional view to form a predetermined inclined surface; an opening portion formed by opening a triangle having one side coincident with the first straight line on the inclined surface of the first inclined surface portion in the vicinity of one end portion of the substrate; a second inclined surface portion that is cut from one end of the substrate along a second straight line that forms a predetermined acute angle with the first straight line on the substrate on the side of the first inclined surface portion, with a thickness thinner than the thickness of the substrate, and that has a V-shape in a cross-sectional view to form a predetermined inclined surface; Equipped with the substrate is split along the first straight line and the substrate is split along the second straight line, so that one end of the substrate becomes a cutting edge and the triangle of the opening and the opened inclined surface become a saw blade. Plastic knife.

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