JP2014100179A - Ceramic kitchen knife and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ceramic kitchen knife having excellent long-term reliability.SOLUTION: A ceramic kitchen knife includes: a blade made of ceramics having a core at a rear end portion thereof; and a handle part covering the core. Metal members hold a part of the core therebetween in the interior of the handle part. A method of manufacturing the ceramic kitchen knife includes: securing the metal members so as to hold therebetween a core included at a rear end portion of a blade made of ceramics; and disposing the core with the metal members secured thereto in a cavity of a metal mold having a shape of the handle part, and injecting heated resin into the cavity and cooling the loaded resin so as to form the handle part.

Description

  The present invention relates to a ceramic knife and a method for manufacturing the same.

  Since conventional metal knives have low hardness, their sharpness deteriorates quickly and frequent re-grinding is required. In addition, there is a problem that the food is easily rusted, the cut food has a metal taste or smell, and is easily corroded by acid or alkali.

  In order to solve such a problem, a ceramic knife represented by zirconia ceramic has been put into practical use (see Patent Documents 1 and 2).

  A ceramic knife is generally composed of a ceramic blade having a cutting blade and a handle portion. Further, since the handle portion uses a different material such as resin or wood for the ceramic blade, there may be a problem of long-term reliability such that the blade is wobbled during use and becomes easy to come off.

  In general, a stopper such as a scissors is used to prevent the blade from coming off from the handle portion. However, when using a stopper, it is necessary to provide a through hole in the ceramic main body, and there is a possibility that chipping or the like often occurs around the through hole. Further, when the stopper is made of metal, the stopper may be corroded.

  There is a need for ceramic knives with excellent long-term reliability.

Japanese Utility Model Publication No. 62-159854 JP 2004-358069 A

  An object of the present invention is to provide a ceramic knife excellent in long-term reliability.

The ceramic knife in one embodiment of the present invention is a ceramic knife provided with a blade made of ceramics having a core at the rear end portion, and a handle portion covering the core,
A plate material sandwiches a part of the core inside the handle portion.

  The method of manufacturing a ceramic knife according to an embodiment of the present invention includes a fixing step of fixing a plate material so as to sandwich the core with respect to a core that the blade made of ceramic has at the rear end, and the plate material is fixed A handle part forming step of disposing the core in the cavity of a mold having a cavity in the shape of a handle part, injecting heated resin into the cavity, and cooling the injected resin to form a handle part including.

According to the ceramic knife of the present invention, since the plate material is provided inside the handle portion so as to sandwich a part of the shank portion of the main body portion, the main body portion is unlikely to wobble and come off easily with respect to the handle portion. . Therefore, a ceramic knife having excellent long-term reliability can be provided.

It is a side view of the ceramic knife in one embodiment of the present invention. It is a top view of the ceramic knife in one embodiment of the present invention. It is a tip view of the ceramic knife in one embodiment of the present invention. It is a rear end view of the ceramic knife in one embodiment of the present invention. (A) is sectional drawing in the AA line of FIG. 1, (b) is sectional drawing in the BB line of FIG. It is a side view in one Embodiment of the blade used for the ceramic knife of this invention.

  Hereinafter, the ceramic knife which is one embodiment of the present invention will be described with reference to FIGS.

<Ceramic knife>
A ceramic knife N according to an embodiment of the present invention includes a blade 1 made of ceramics and a handle portion 2 as shown in FIGS. The size of the ceramic knife N is not particularly limited. For example, various lengths of about 8 cm to 40 cm are provided. Various types of knives can be used for Santoku knives, petty knives, fruit knives, children's knives, and the like.

  As shown in FIG. 5, the blade 1 is made of a zirconia sintered body, and has a blade portion 11 having a cutting edge ridge line at a tip portion and a core 12 covered by a handle portion 2 at a rear end portion. . What is necessary is just to set the magnitude | size and thickness of the blade 1 suitably according to the use of the ceramic knife to be used. The width (width) of the widest part of the blade 1 is about 30 mm to 50 mm, and the thickness of the blade 1 is about 1.3 mm to 2.5 mm at the thickest part. The thickness of the blade 1 is 1 to 10 times, preferably 1 to 4 times, more preferably 2 to 4 times the thickness of the plate 3 described later. Is preferable in that it can be securely fixed.

  The blade 1 (blade 11) further has a cutting edge ridge 13, two side surfaces 14 continuous to the cutting edge ridge 13, and an upper surface 15 connected to the two side surfaces 14. . Specifically, the blade portion 11 is ground by polishing the side surface portion 14 to form the cutting edge ridge line 13. Accordingly, the blade 1 has a substantially triangular shape (so-called clam shape, main blade shape, or single-edged shape) or a substantially pentagonal shape (so-called stepped shape) in a cross-sectional view. On the other hand, since the core 12 forms the lower surface part 16 instead of the cutting edge ridge line 13, it becomes a substantially quadrangular shape in sectional view.

  The blade portion 11 is a portion of the blade 1 that is not covered with the handle portion 2. The size of the blade 1 is appropriately set according to the application. For example, the blade span (the length of the portion with the blade) is, for example, about 5 cm to 20 cm.

  The core 12 is a portion of the blade 1 that is in the handle portion 2, and is a contact portion between the blade 1 and the handle portion 2.

  The core 12 may have a cutout portion 17 on at least one of the cutting edge ridge side 13 (lower surface portion 16) side and the upper surface portion 15 side in a side view. By having such a notch, it is difficult for the blade 1 to come off the handle 2. A plurality of notches 17 may be provided. In particular, it is more preferable to have the cutouts 17 on the cutting edge ridge side 13 (lower surface part 16) side and the upper surface part 15 side in that the blade 1 is difficult to come off from the handle part 2. For example, in FIG. 6, one notch portion 17 is formed on each of the upper surface portion 15 side and the lower surface portion 16 side of the blade 1.

  The handle portion 2 is provided so as to cover the core 12 located at the rear end portion of the blade 1. Specifically, the handle portion 2 and the blade 1 are fixed to each other with two plate members 3 sandwiching a part of the core 12 inside the handle portion 2. By fixing the blade 1 and the handle portion 2 with the two plate members 3 in this manner, the wobbling of the blade 1 can be reduced and the removal of the blade 1 can be suppressed, and excellent long-term reliability can be obtained. . Further, as compared with the case where the blade body and the handle portion are stopped with a stopper, it is not necessary to make a through hole in the ceramic blade body, and therefore, there is an effect that it is difficult to chip.

  As the material of the handle portion 2, wood, resin material, or the like is used. Examples of the resin material include synthetic resins such as polyethylene, polypropylene, and polyester, elastomer resins, or synthetic rubber vulcanized to an appropriate hardness. An antibacterial agent may be added to the resin as necessary. When the handle part 2 is made of resin, it is preferable to use a resin having a flexural modulus of 400 to 4000 kg / cm 2 and a compressive modulus of about 520 to 3300 kg / cm 2. When a resin material is used as the handle portion 2, an antibacterial agent, a pigment, or the like may be used as appropriate.

  The board | plate material 3 should just be a hard material, and is not restrict | limited in particular. Wood, metal materials such as iron, steel plates (for example, silicon steel plates, stainless steel), aluminum alloys, nickel alloys (permalloy), amorphous alloy foils and the like are used. Magnetic materials such as iron, silicon steel, and stainless steel are used from the viewpoint of security because they can be detected by magnetism, X-rays, and the like.

  When the plate material 3 is a metal material, it is preferable to coat with, for example, a fluororesin, a nylon resin or the like from the viewpoint of suppressing corrosion.

  The plate material 3 is used for fixing the blade 1 as described above. Specifically, a part of the core 12 is sandwiched and fixed by the plate material 3. The size and shape of the plate member 3 may be any size as long as they can be accommodated inside the handle portion 2. For example, as shown in FIG. 5, the plate member 3 has a rectangular shape and a part thereof is tapered. The size of the plate material is, for example, about 10 mm to 20 mm in width, 70 mm to 100 mm in length, and about 0.1 mm to 1 mm in thickness. In this embodiment, as shown in FIG. 5, it has a substantially hexagonal shape with one end of a rectangle tapered.

  The plate material 3 may be sandwiched between the core 12 and one or may be sandwiched between at least two plate materials. In the present embodiment, two plate members 3 are arranged on both side surfaces of the core 12 and sandwich a part of the core 12. In this way, it is sufficient that the core is sandwiched between two plate materials, and in addition to the two plate materials sandwiching the core, a configuration in which a plurality of plate materials are arranged on one side surface portion may be employed. In the present embodiment, two plate materials having the same shape are used, but the two plate materials may have the same shape or different shapes.

  Further, when a plurality of plate materials 3 are arranged, the materials of these plate materials may be different. For example, the structure may be such that both side surfaces of the core are sandwiched between two wooden plates, and the outside of the wooden plate is sandwiched between two metal plates. In this case, the fixing force is further improved.

  As shown in FIGS. 5A and 5B, the plate member 3 includes a contact portion 31 that contacts the core 12 and a protruding portion 32 that protrudes from the core 12. From the viewpoint of suppressing the wobbling of the blade 1, it is preferable that the protruding portion 32 protrudes in the length direction of the blade 1. Moreover, it is preferable that the area of the protruding portion 32 is larger than the area of the contact portion 31.

  The contact portion 31 is a portion where the plate material 3 comes into contact with the blade 1 (core 12). You may contact between the board | plate material 3 and the blade 1 through the adhesive agent. The contact position between the blade 1 and the plate material 3 is not particularly limited. For example, in the height direction from the upper surface of the blade 1 toward the lower surface, the upper surface side may be contacted, the lower surface side may be contacted, or the intermediate portion between the upper surface and the lower surface in the height direction is contacted You may do it. Further, when the blade 1 has the cutout portion 17, the cutout portion 17 may be in contact with the cutout portion 17 so as to overlap a part or the whole of the cutout portion 17, or may not come into contact with the cutout portion 17. In the present embodiment, the plate member 3 is disposed along the ridge line on the upper surface side of the side surface portion 14 of the blade 1 and overlaps with a part of the notch portion located on the cutting edge ridge side (lower surface side). Is arranged.

  In the present embodiment, the protruding portions 32 of the two plate members 3 face each other, and a gap is formed. It is preferable that a resin or the like is disposed in the gap. For example, when the handle portion is manufactured by resin molding, these gaps are filled in the gap, and the fixation between the blade and the handle portion is improved. Furthermore, although not shown, when a part of these protrusions 32 is in contact, the blade 1 is difficult to be removed from the handle part 2 due to the resin disposed in the gap and the contact part between the protrusions.

  The protruding portion 32 suppresses the wobbling of the blade 1 from the left and right with respect to the handle portion 2. In the present embodiment, the rear end portion is tapered according to the shape of the handle portion 2.

The plate 3 may have a through hole 33. In this case, for example, by providing a convex portion to be inserted into the through hole 33 in the handle portion 2 at the joint portion between the handle portion 2 and the plate material 3,
An anchor effect is produced, and the fixing force between the blade 1 and the handle portion is further improved. The size and the number of the through holes 33 can be appropriately set according to the design. Although both the contact part 31 and the protrusion part 32 may be provided in the through-hole 33, it is preferable to be provided in the contact part 31 from the point of a fixed force improvement.

  The surface of the plate member 3 may be an uneven surface from the viewpoint of increasing the fixing force with the blade 1 or the handle portion. Even when the blade 1 and the plate material 3 are fixed with an adhesive, the fixing force can be further improved by having such an uneven surface.

  In the present embodiment, although not shown, at least a part of the two plate members 3 may be in contact with each other. In particular, when the handle portion 2 is a resin material, the resin material enters between the opposing surfaces of the two plate members, and the fixing force between the blade 1 and the handle portion is further improved. As a method for contacting the plate members 3, for example, at least one of the plate members 3 may be bent and brought into contact, or the contact portion of the core 12 where two plate members are in contact is polished in a tapered shape in advance. It is good also as a structure where two board | plate materials contact. In addition, even if it clips using the U-shaped board | plate material 2 in sectional view instead of the two board | plate materials 3, the effect similar to the said effect can be acquired.

  In the present embodiment, although not shown, the plate 3 may overlap at least a part of the notch 17 in a side view. In particular, when the handle portion 2 is a resin material, the resin material enters the gap between the plate material 3 and the notch portion 17, and the fixing force between the blade 1 and the handle portion is further improved. For example, as shown in FIG. 6, when the plate material 3 is arranged so as to overlap the two notches 17 with respect to the blade 1 having the notches 17 on the lower surface side (the cutting edge ridge side) and the upper surface side, respectively. The fixing force between the blade 1 and the handle portion 2 is further improved.

<Manufacturing method of ceramic knife>
A method of manufacturing a ceramic knife according to an embodiment of the present invention includes a fixing step of fixing two plate materials so as to sandwich the core with respect to a core located at the rear end portion of the blade made of ceramic, and the plate material A handle part is formed in which a core with a fixed portion is placed in a cavity of a mold having a cavity in the shape of a handle part, and heated resin is injected into the cavity, and the injected resin is cooled to form a handle part. Process. Specific steps will be described below.

  First, prepare a blade made of ceramics. For example, the blade is granulated by adding 2 to 10% by mass of an acrylic, wax or PEG binder to zirconia powder containing 1 to 4 mol% of yttria powder.

  The obtained granule is shaped like a blade 1 shown in FIG. 5 at a molding pressure of 1000 to 1500 kg / cm 2 using a mold, and then fired to obtain a zirconia sintered body. The obtained zirconia sintered body is bladed by a normal method to obtain a blade made of ceramics.

  In addition to the molding method using a mold, the molding method can be molded by a method that is usually performed by those skilled in the art. For example, cast molding, plastic molding (injection), rubber press, hot press, etc. can be used as appropriate.

  What is necessary is just to set a calcination temperature suitably according to material. In the case of zirconia, it is performed at 1300 to 1500 ° C. After calcination, the obtained zirconia sintered body may be subjected to HIP treatment for 2 to 5 hours at a pressure of 1500 to 2500 kg / cm 2 as necessary.

  Next, two plate members are fixed to the core located at the rear end of the blade made of ceramics so as to sandwich the core. The plate material may be fixed securely using an adhesive as described above, or may be fixed using a screw or the like. It may be a temporary fixing degree such as a tape. Or you may fix temporarily using auxiliary tools, such as a clip, in the range which does not impair the function of a kitchen knife.

  Furthermore, a handle portion is formed so as to cover the core to which the plate material is fixed. In the present embodiment, a resin handle is used. In addition, when using a wood-like handle part, it is necessary to provide the insertion part which can insert the core to which the board | plate material was fixed previously.

  When using a resin handle as in the present embodiment, specifically, a mold having a cavity in the shape of a hand object is prepared, and a core on which the plate material is fixed is disposed in the cavity. . Thereafter, heated resin is injected into the cavity. What is necessary is just to set the heating temperature of resin according to resin to be used. For example, when polypropylene resin is used, the temperature may be set to 160 to 240 ° C.

  Further, the injected resin is cooled. The cooling condition may be a condition that does not allow a large number of large voids (nests) in forming the handle portion.

Example 1
A silicon steel plate was bonded to each side surface of a portion corresponding to the core of a ceramic blade having a blade span of 14 cm with an adhesive. Thereafter, a handle portion was formed of an elastomer resin on the core portion to obtain a ceramic knife as shown in FIG.

  Next, a hole with a diameter of 6 mm is made in the handle portion of the obtained ceramic knife, and a pin is inserted into the hole and fixed, and the tip of the blade is sandwiched and pulled to determine the breaking tension. (Shimadzu Corporation) was used for measurement. Specifically, the crosshead speed was set to 0.5 mm / min, and measurement was performed under measurement conditions of a temperature of 25 ° C. and a humidity of 68%. The results are shown in Table 1. In addition, regarding the item of breakage of the hole in Table 1, “◯” was entered when the hole was broken by pulling the pin inserted into the hole.

(Example 2)
A ceramic knife was obtained in the same manner as in Example 1 except that a ceramic blade having a blade span of 11 cm was used instead of the blade of Example 1, and the breaking tension was measured. The results are shown in Table 1.

(Comparative Examples 1 and 2)
A ceramic knife was obtained in the same manner as in Examples 1 and 2 except that no silicon steel plate was used, and the breaking tension was measured. The results are shown in Table 1.

  From the results in Table 1, it can be seen that the ceramic knives sandwiched between the silicon steel plates of Examples 1 and 2 have a higher breaking tension than the ceramic knives not using the silicon steel plates of Comparative Examples 1 and 2. These facts indicate that the ceramic knife with the blade sandwiched between the plate materials is less likely to come out of the blade with respect to the handle portion and has excellent long-term reliability.

(Examples 3-4 and Comparative Examples 3-4)
A ceramic knife was obtained using the same method as in Examples 1 and 2 and Comparative Examples 1 and 2 except that a polypropylene resin was used instead of the elastomer resin as the material of the handle part, and the breaking tension was measured. Also in the ceramic knife using polypropylene resin for the handle part, the breaking tension of the ceramic knife with the blade sandwiched between the silicon steel plates of Examples 3 and 4 was large.

N ceramic knife 1 blade 11 blade part 12 core 13 cutting edge ridge 14 side part 15 upper surface part 16 lower surface part 17 notch part 2 handle part 3 plate material 31 adhesive part 32 projecting part 33 through hole

Claims (12)

A ceramic knife provided with a blade made of ceramics having a core at the rear end portion, and a handle portion covering the core,
A ceramic knife characterized in that a plate material sandwiches a part of the core inside the handle portion.   2. The ceramic knife according to claim 1, wherein at least two of the plate members are respectively disposed on both side surface portions of the core inside the handle portion and sandwich a part of the core. The blade has a cutting edge ridge, two side surfaces continuous to the cutting edge, and an upper surface connected to the two side surfaces,
3. The ceramic knife according to claim 1, wherein the core has a notch on at least one of the cutting edge ridge side and the upper surface side in a side view.   The ceramic knife according to any one of claims 1 to 3, wherein the plate material is made of a metal material.   The ceramic knife according to claim 4, wherein the handle portion is made of a resin material.   The ceramic knife according to any one of claims 3 to 5, wherein the plate material overlaps at least a part of the notch in a side view.   The ceramic knife according to any one of claims 1 to 6, wherein the thickness of the blade is 1 to 10 times the thickness of the plate.   The ceramic knife according to any one of claims 3 to 7, wherein the core has the cutout portions on the cutting edge ridge side and the upper surface side in a side view, respectively.   The ceramic knife according to any one of claims 2 to 8, wherein at least a part of the at least two plate members are in contact with each other. The plate has a through hole,
The ceramic part according to any one of claims 1 to 9, wherein the handle part is provided with a convex part inserted into the through hole at a joint part between the handle part and the plate member. Kitchen knife. A method for manufacturing a ceramic knife according to any one of claims 1 to 10,
A fixing step of fixing a plate material so as to sandwich the core held by a ceramic blade at the rear end, and a gold having a cavity in the shape of a handle portion with the core fixed to the plate material A method for manufacturing a ceramic knife comprising a handle portion forming step of placing a heated resin into the cavity of the mold and injecting heated resin into the cavity, and cooling the injected resin to form a handle portion. The method for manufacturing a ceramic knife according to claim 11, wherein in the fixing step, the plate material is fixed to the core with an adhesive.

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