CN106659289A - Tooth brush - Google Patents

Abstract

The invention aims to provide a toothbrush capable of inhibiting oral cavity injury of a user. The toothbrush has: a head (14) having a flocked surface (21-1b) on the tip side; and a handle (16) which is disposed on the rear end side with respect to the head and includes a handle body (31), and the toothbrush includes: a deformation part (15A) which is arranged between the hair-planting surface and the handle part and is deformed by an external force applied to the head part; a hard member (17) which is arranged from the head part over a part of the tip side of the shank part and is formed of a hard resin; and a soft portion (26) which is disposed from the deforming portion toward the rear end side, accommodates at least a part of the hard member therein, and is formed of a soft resin.

Description

toothbrush

technical field

The present invention relates to a toothbrush, and particularly to a toothbrush capable of suppressing damage to a user's oral cavity.

this application claims priority based on Patent Application No. 2014-177334 for which it applied to Japan on September 1, 2014, The content is used here.

Background technique

In the past, when using a toothbrush (specifically, when the toothbrush is put in the mouth), there are cases where oral trauma is caused by a fall, especially when the user of the toothbrush is an infant aged 1 to 3 years old, the oral cavity is injured. There are many cases of trauma.

Conventionally, there is a toothbrush disclosed in Patent Document 1 as a toothbrush capable of suppressing chipping and breaking of the head and neck.

Patent Document 1 discloses a toothbrush in which a coating layer made of soft resin is formed on the surface of a base made of hard resin, and the coating layer covers more than 70% of the total surface area of the head and neck. .

In addition, Patent Document 1 discloses that the overall thickness of the head and neck (thickness of the sum of the thickness of the base and the thickness of the covering layer covering the base) is 3 to 5 mm, and the The thickness of the base and the neck portion is 2 to 4 mm, and the thickness of the covering layer is 0.5 to 2 mm (preferably 0.8 to 1.5 mm).

Patent Document 1 discloses that, by adopting the above-mentioned structure, even when an excessive load is applied to the head and neck, it is possible to make the handle difficult to break, or even when the head or neck is broken. Also, the broken part can be suppressed from being exposed from the covering layer.

In the toothbrush disclosed in Patent Document 1 having the above-mentioned structure, the base constituting the tip of the head is covered with a soft resin. The resin functions as a cushioning material.

Therefore, by using the toothbrush disclosed in Patent Document 1, it is possible to suppress damage to the oral cavity due to the distal end portion of the head.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2013-458

However, in the neck of the toothbrush disclosed in Patent Document 1, a base (thickness 2 to 4 mm) that is thinner than the base and made of soft resin is provided to cover the surface of the base (thickness 2 to 4 mm) constituting the neck. Covering layer (preferably 0.8 to 1.5 mm in thickness).

Therefore, the neck portion of the toothbrush disclosed in Patent Document 1 has a structure in which the ratio of the hard resin constituting the base is higher than the ratio of the soft resin.

Therefore, in the head of the toothbrush disclosed in Patent Document 1, for example, when an external force is applied to the extension direction of the toothbrush (specifically, the direction from the rear end of the toothbrush toward the top end), the user's oral cavity will not be damaged. It is relatively difficult to bend in such a way that the external force transmitted to the tip of the head is fully released (however, it is easier to bend than the case where the entire body is made of hard resin).

Therefore, when a strong external force is applied in the direction from the rear end of the toothbrush toward the front end while the toothbrush disclosed in Patent Document 1 is put in the mouth, there is a possibility of damage to the user's oral cavity.

In particular, when the user of the toothbrush is an infant of 1 to 3 years old, the risk of damage in the oral cavity becomes high.

Contents of the invention

This invention was made|formed in view of the said subject, and it aims at providing the toothbrush which can suppress damage in a user's oral cavity.

means to solve the problem

In order to solve the above-mentioned problems, a toothbrush according to an aspect of the present invention is characterized in that it has: a head having a flocking surface on the tip side; and a handle arranged on the rear end side relative to the head, And including the handle main body, the toothbrush includes: a deformation part, which is arranged between the flocking surface and the handle, and is deformed due to an external force applied to the head; a hard part, the a hard member is arranged from the head part over a part of the front end side of the handle and is formed of hard resin; It accommodates at least a part of the hard member and is formed of soft resin.

In addition, the toothbrush according to one aspect of the present invention described above includes a second deforming portion arranged on the handle and deformed by the external force.

In addition, the toothbrush according to one aspect of the present invention is characterized in that the handle has at least one ring-shaped recess with a reduced diameter in the extending direction of the handle, and the second deforming part is arranged in an arrangement of the recess. set location.

In addition, the toothbrush according to one aspect of the present invention is characterized in that the hard member has a first exposed portion and a second exposed portion, the first exposed portion is exposed toward the flocking surface on the head portion, and the second exposed portion is exposed to the flocking surface side. The two exposed parts are exposed to opposite sides of the flocking surface.

In addition, the toothbrush according to one aspect of the present invention is characterized in that the hard member has a columnar first protrusion and a columnar second protrusion, and the first protrusion is located on the side of the handle facing the flocking surface. Protruding and exposing, the second protruding part protrudes and exposes on the side opposite to the flocking surface at the handle.

In addition, the toothbrush according to the aspect of the present invention described above is characterized in that the first protrusion is exposed through a first opening formed on the flocking surface side of the soft part, and the second protrusion is formed through a It is exposed at the second opening on the side opposite to the side of the flocking surface of the soft part.

In addition, the toothbrush according to the aspect of the present invention is characterized in that the soft portion of the handle has a tapered tip portion that tapers toward the tip side, and the first opening and the second An opening is formed in the tapered tip.

In addition, the toothbrush according to one aspect of the present invention is characterized in that the soft part has a parting line on the surface, and the first protruding part faces in a direction perpendicular to the flocking surface via the parting line. One side is exposed, and the second protrusion is exposed to the other side in the orthogonal direction across the parting line.

In addition, the toothbrush according to one aspect of the present invention is characterized in that the hard member is arranged to extend to the handle, and the distal end surface of the first protrusion and the distal end surface of the second protrusion are in contact with the The outer surface of the handle is flush.

In addition, in the toothbrush according to the aspect of the present invention described above, a part of the hard member disposed on the rear end side of the handle with respect to the first protrusion and the second protrusion has a diameter A shape that becomes smaller toward the rear end side of the shank.

In addition, the toothbrush according to one aspect of the present invention is characterized in that at least the tip of the head is made of a first soft resin softer than the hard resin, and the handle main body is made of soft resin softer than the hard resin. The second soft resin is made of the second soft resin, and the soft portion is made of the second soft resin.

In addition, the toothbrush according to one aspect of the present invention described above is characterized in that the first width in the first direction of the hard member between the flocking surface and the handle is larger than the second width in the second direction. , the first direction is perpendicular to the flocking surface, and the second direction is perpendicular to the length direction of the handle and the first direction.

In addition, the toothbrush according to one aspect of the present invention is characterized in that the hard member of the head includes the flocking surface and a base member having a plurality of flocking holes, and the first soft resin is arranged such that A part of the base member is covered in a state in which the flocking surface and the plurality of flocking holes are exposed.

In addition, the toothbrush according to an aspect of the present invention described above is characterized in that a neck portion is disposed between the flocking surface and the handle, and the width of the neck portion in the second direction is equal to or less than the width of the head portion. The second direction is perpendicular to the first direction and the length direction of the handle, and the first direction is perpendicular to the flocking surface.

Invention effect

According to the toothbrush of this invention, damage to a user's oral cavity can be suppressed.

Description of drawings

Fig. 1 is a side view of a toothbrush according to an embodiment of the present invention.

Fig. 2 is a front view of the toothbrush shown in Fig. 1 .

Fig. 3 is a rear view of the toothbrush shown in Fig. 1 .

Fig. 4 is an enlarged side view of the hard member shown in Fig. 1 .

Fig. 5 is an enlarged front view of the hard member shown in Fig. 2 .

Fig. 6 is an enlarged rear view of the hard member shown in Fig. 3 .

Fig. 7 is a cross-sectional view along line A-A of the hard member shown in Fig. 4 .

Fig. 8 is a cross-sectional view along line B-B of the hard component (specifically, the first part) shown in Fig. 4 .

Fig. 9 is a cross-sectional view along line C-C of the hard member (specifically, the second part) shown in Fig. 4 .

Fig. 10 is a cross-sectional view taken along line D-D of the hard member (specifically, the second part) shown in Fig. 4 .

Fig. 11 is a cross-sectional view showing a manufacturing process of the toothbrush according to the present embodiment, and is a diagram for explaining a process of forming a hard member using a first die.

12 is a cross-sectional view showing the manufacturing process of the toothbrush according to this embodiment, and is a diagram for explaining a process of forming the first soft resin, the soft part, and the handle main body using the second mold.

Fig. 13 is a side view showing a modified example of the toothbrush according to the embodiment of the present invention.

Fig. 14 is a front view of the toothbrush shown in Fig. 13 .

detailed description

Hereinafter, embodiments to which the present invention is applied will be described in detail with reference to the drawings. In addition, the drawings used in the following description are for explaining the structure of embodiment of this invention, and the size, thickness, dimension, etc. of each part shown in illustration may differ from the dimensional relationship of an actual toothbrush.

(implementation mode)

Fig. 1 is a side view of a toothbrush according to an embodiment of the present invention. Fig. 2 is a front view of the toothbrush shown in Fig. 1 . In FIG. 2 , illustration of the bristle portion 12 composed of a plurality of bristle bundles 12 - 1 shown in FIG. 1 is omitted for convenience of description. Fig. 3 is a rear view of the toothbrush shown in Fig. 1 .

Fig. 4 is an enlarged side view of the hard member shown in Fig. 1 . Fig. 5 is an enlarged front view of the hard member shown in Fig. 2 . Fig. 6 is an enlarged rear view of the hard member shown in Fig. 3 .

In the structures shown in FIGS. 1 to 6 , the same components are denoted by the same symbols. The X direction shown in FIGS. 1 to 6 represents the extending direction of the handle body 11 (the extending direction of the neck portion 15 ) in the state where the toothbrush 10 is not used.

The Y direction shown in FIGS. 2 , 3 , 5 , and 6 represents the width direction of the toothbrush 10 (in other words, the second direction perpendicular to the Z direction and the X direction).

The Z direction shown in FIG. 1 and FIG. 4 shows the 1st direction orthogonal to the hair-implanted surface 21-1b in the state which the toothbrush 10 is not used.

In addition, in FIGS. 4-6, the code|symbol of the component of the toothbrush 10 other than the component of the hard member 17 is shown also for convenience of description.

Referring to FIGS. 1 to 6 , a toothbrush 10 according to this embodiment has a handle body 11 and a bristle portion 12 .

The handle body 11 has a head 14 , a neck 15 , a handle 16 , the head 14 , the neck 15 , and a hard member 17 constituting a part of the handle 16 .

In the present embodiment, the following toothbrush 10 will be described: between the flocking surface 21-1b and the handle 16, a toothbrush whose width in the second direction (Y direction) is wider than the width of the head 14 (maximum width in the Y direction) is arranged between the flocking surface 21-1b and the handle 16. Small neck 15.

The head portion 14 has a base member 21 made of hard resin and a first soft resin 22 covering a part of the base member 21 . The base member 21 is a part of the constituent elements of the hard member 17 made of hard resin, and has a base member main body 21-1 and two support portions 21-2.

The base member main body 21-1 is formed in such a shape that the outer shape of the head 14 is reduced by about 1 to 2 mm so that the first soft resin 22 can be disposed on the side and bottom surface 21-1a of the base member main body 21-1. The base member main body 21-1 has a front end part 21-1A, a bottom surface 21-1a, a flocking surface 21-1b, and a flocking hole 21-1B.

The tip portion 21 - 1A is a portion located on the opposite side to the side where the head portion 14 and the neck portion 15 are connected in the base member main body 21 - 1 . Tip portion 21 - 1A is a portion that faces the inside of the user's oral cavity when the user uses toothbrush 10 to brush their teeth. The shape of the tip portion 21-1a may be, for example, a shape with a circular arc (arc shape).

Fig. 7 is a cross-sectional view along line A-A of the hard member shown in Fig. 4 . In FIG. 7 , the same components as those of the structures shown in FIGS. 1 to 6 are denoted by the same symbols. In addition, in FIG. 7, the code|symbol of the component of the toothbrush 10 other than the component of the hard member 17 is also shown for convenience of description.

Referring to Fig. 1, Fig. 3, Fig. 4, Fig. 6 and Fig. 7, the bottom surface 21-1a is the part covered by the first soft resin 22, and is arranged on the opposite side of the flocking surface 21-1b. The bottom surface 21-1a can be, for example, a flat surface.

The flocking surface 21-1b is a flat surface. The hair-planting surface 21-1b exposes a plurality of hair-planting holes 21-1B. The flocking surface 21 - 1 b is exposed from the first soft resin 22 as the first exposed portion of the head 14 .

In this way, the base member main body 21-1 is formed using a hard resin harder than the first soft resin 22, and the plurality of tufting holes 21-1B and the tufting surface 21-1b are exposed from the first soft resin 22, Therefore, the hair bundle 12-1 which comprises the bristle part 12 can be hair-planted (implanted) in some hair-planting hole 21-1B using the flat wire type hair-planting method.

The hair-planting surface 21-1b is when using the second mold 51 shown in Figure 12 described later to make the first soft resin 22, the soft part 26 and the handle main body 31 resin molding, and a mold 51-2 (refer to Figure 12) the inner surface of the contact surface.

Thus, the flocking surface 21-1b is in contact with the inner surface of one mold 51-2 constituting the second mold 51, thereby suppressing the formation of the first soft resin 22 in the plurality of flocking holes 21-1B and the flocking surface 21-1b.

A plurality of tufting holes 21-1B are provided in the base member main body 21-1 constituting the side of the tufting surface 21-1b. The hair-planting hole 21-1B is a hole in which the hair bundle 12-1 which comprises the bristle part 12 is hair-planted.

As the arrangement of the plurality of hair-planting holes 21-1B, for example, the arrangement shown in FIG. 2 can be used, but it is not limited thereto, and arbitrary arrangement patterns such as a so-called checkerboard arrangement and a zigzag arrangement may be used.

In addition, the number of some hair-planting holes 21-1B is not limited to the number of the hair-planting holes 21-1B shown in FIG. 2, For example, it can set suitably in the range of 10-60 holes.

That is, the arrangement|sequence of some hair-planting holes 21-1B, and the number of hair-planting holes 21-1B can be set suitably according to the objective.

The shape of the hair transplant hole 21-1B is not particularly limited, and for example, a circle such as a perfect circle or an ellipse, a polygon such as a triangle or a quadrangle, or the like can be used.

In addition, the diameter of the hair-planting hole 21-1B can be determined according to the thickness of the hair bundle 12-1, Specifically, it can set suitably within the range of 1-3 mm, for example.

In the case where the thickness of the head portion 14 in the Z direction is 5.0 mm, the thickness of the base member main body 21-1 in the Z direction (in other words, the thickness between the bottom surface 21-1a and the flocking surface 21-1b) can be, for example, 4.2mm. In this case, the depth of the some tufting hole 21-1B can be 2.5 mm, for example, based on the tufting surface 21-1b. An example of the thickness of the head portion 14 is the thickness measured at the central portion of the head portion 14 in the X direction.

The two support portions 21-2 are provided so as to protrude from the bottom surface 21-1a of the base member main body 21-1 in the Z direction (downward in the case of the state shown in FIG. 1 ). One of the two support parts 21-2 is arranged on the front end side of the base member main body 21-1, and the other is arranged on the rear end side of the base member main body 21-1. The two support parts 21-2 are arranged so as to face each other in the X direction. Each of the two support parts 21-2 has a protruding surface 21-2a formed as a flat surface.

The two protruding surfaces 21 - 2 a are exposed from the outer surface of the first soft resin 22 and are flush with the outer surface of the first soft resin 22 . That is, as the 2nd exposed part of the head part 14, the support part 21-2 is exposed on the side opposite to the flocking surface 21-1b as shown in FIG.

The protruding surface 21-2a is compatible with the inner surface of the first mold 41 (see FIG. 11) when the hard member 17 including the base member main body 21-1 is molded using the first mold 41 shown in FIG. 11 described later. contact part.

In this way, the protruding surface 21-2a contacts the inner surface of the first mold 41 (see FIG. 11 ), and the first soft resin 22 can be formed around the two support portions 21-2 and the bottom surface 21-1a.

That is, the amount of protrusion of the two supporting parts 21-2 (in other words, the distance to the protrusion surface 21-2a when the bottom surface 21-1a is used as a reference) is related to the Z direction of the first soft resin 22 disposed on the bottom surface 21-1a. of equal thickness.

Therefore, the amount of protrusion of the two support portions 21-2 can be appropriately set according to the thickness of the first soft resin 22 arranged on the bottom surface 21-1a. When the thickness of the head part 14 in the Z direction is 5.0 mm and the thickness of the base member main body 21 - 1 in the Z direction is 4.2 mm, the amount of protrusion of the two support parts 21 - 2 can be, for example, 0.8 mm. An example of the thickness of the head 14 and the base member main body 21 - 1 is the thickness measured at the central portion of the head 14 in the X direction.

In addition, in FIG. 1 and FIG. 3 , an example in which there are two support portions 21 - 2 has been exemplified and described, but the number of support portions 21 - 2 may be one or more, and is not limited to two.

The rear end of the base member 21 configured as described above is integrally formed with the tip end portion of the core 25 (one end of the core 25 ).

As the hard resin constituting the base member 21, a resin harder than the first soft resin 22 is used. Specifically, as the hard resin constituting the base member main body 21 - 1 , for example, a resin having a flexural modulus (JIS K7203) within a range of 500 to 3000 MPa can be used.

Specific examples of such a hard resin include polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene terephthalate 1,4-cyclohexanedimethanol formate (PCT), polyoxymethylene (POM), polystyrene (PS), acrylonitrile-butadiene-styrene resin (ABS), cellulose propionate (CP), Polyarylate, polycarbonate, acrylonitrile-styrene copolymer resin (AS) and the like, among which polybutylene terephthalate (PBT) is preferable.

Polybutylene terephthalate (PBT) has a high breaking strength, so that the base member 21 can be suppressed from being broken or partially damaged. One of the above-mentioned hard resins may be used alone, or two or more of them may be used in combination as appropriate.

The first soft resin 22 is provided as follows: in the state that the flocking surface 21-1b, the plurality of flocking holes 21-1B, and the end faces 21-2a of the two supporting parts 21-2 are exposed, the base member main body 21-1 is covered. The side and bottom surface 21-1a.

Thereby, the first soft resin 22 is disposed so as to cover the distal end portion 21-1A of the base member main body 21-1.

In this way, the first soft resin 22 is arranged so as to cover the front end 21-1A of the base member main body 21-1, so that when the user uses the toothbrush 10, the first soft resin 22 arranged on the front end 21-1A The resin 22 functions as a cushioning material, so when an external force is applied in the direction from the rear end side of the toothbrush 10 toward the front end side, and the first soft resin 22 arranged at the top end 21-1A strongly presses the user's oral cavity, it can Inhibits damage to the user's oral cavity.

The thickness of the first soft resin 22 arranged on the side surface and the bottom surface 21-1a of the base member main body 21-1 can be appropriately set within a range of 0.2 to 2.0 mm, for example, 0.8 mm according to the purpose.

In addition, in FIGS. 1 to 3, as an example, the case where the first soft resin 22 is provided so as to cover the side surface and the bottom surface 21-1a of the base member main body 21-1 has been described as an example, but the first The soft resin 22 may be disposed so as to cover at least the distal end portion 21-1A of the base member main body 21-1.

As the first soft resin 22 , for example, a soft resin whose hardness is JIS K 7215 Shore A hardness of 90 or less may be used. As such a soft resin, for example, elastomer resins such as polyolefin elastomers, styrene elastomers, and polyester elastomers can be exemplified, but among them, from the viewpoint of weldability with polypropylene (PP), , preferably styrenic elastomers.

Specific examples of the styrene-based elastomer include SEPTON (trade name) manufactured by Kuraray Co., Ltd., Leostomer (trade name) manufactured by RIKEN TECHNOS CO., LTD., and the like.

In addition, the first soft resin 22 may be appropriately selected according to the type of hard resin constituting the base member 21 .

Specifically, when polypropylene (PP) is used as the hard resin constituting the base member 21, as the first soft resin 22, for example, a polyolefin-based elastomer or a styrene-based elastomer is preferable, and more preferably Styrenic elastomer.

By setting the combination of the hard resin constituting the base member 21 and the first soft resin 22 as described above, sufficient adhesion between the base member 21 and the first soft resin 22 can be ensured.

The length (length in the X direction) of the head portion 14 configured as described above is not particularly limited, but is preferably within a range of 10 to 30 mm, more preferably within a range of 12 to 28 mm, for example.

When the length of the head part 14 is 10 mm or more, the area of the hair-implantation surface 21-1b which can implant|plant the hair bundle 12-1 can fully be ensured. Moreover, when the length of the head part 14 is 30 mm or less, the operability of the toothbrush 10 in an oral cavity can be improved.

The width of the head 14 configured as described above (the maximum width of the head 14 in the Y direction) is not particularly limited, for example, it is preferably in the range of 7 to 13 mm, and more preferably in the range of 8 to 12 mm.

When the width of the head part 14 is 7 mm or more, the area of the hair-implantation surface 21-1b which can implant|plant the hair bundle 12-1 can fully be ensured.

Moreover, when the width of the head part 14 is 13 mm or less, the operability of the toothbrush 10 in an oral cavity can be improved.

Here, referring to FIG. 2 , the position of the boundary between the rear end of the head 14 and the top end of the neck 15 and the position of the boundary between the rear end of the neck 15 and the top end of the handle 16 are defined.

In the present invention, the neck includes a portion whose width in the Y direction is equal to or smaller than the maximum width of the head 14 between the flocking surface 21 - 1 b and the handle 16 .

In addition, in this embodiment, in the X direction from the front end of the head 14 toward the rear end of the handle 16, the width in the Y direction becomes narrower, the amount of change in the width becomes larger, and finally the amount of change in the width in the Y direction The position where it almost disappears is defined as the position of the boundary between the rear end of the head 14 and the top end of the neck 15 .

In addition, in the X direction from the top end of the neck 15 toward the rear end of the handle 16, the width in the Y direction becomes wider, the amount of change in the width becomes larger, and finally the position in the Y direction where the amount of change in the width almost disappears is defined as is the position of the boundary between the rear end of the neck 15 and the top end of the handle 16 .

In addition, in the present invention, the position on the rear end side of the stem part 16 of the hair transplanting hole arranged at the position farthest from the top end of the head part 14 in the X direction from the top end of the head part 14 may also be referred to as the head part 14. The position of the boundary between the rear end and the top of the neck 15.

The length of the neck 15 in the X direction can be appropriately set, for example, within a range of 20 to 60 mm. In this case, the total length of the head length and neck length can be appropriately set, for example, within a range of 40 to 85 mm. .

The neck 15 is the part connecting the head 14 and the handle 16 . The width of the neck portion 15 in the Y direction is narrower than the widths of the head portion 14 and the stem portion 16 . The thickness of the neck portion 15 in the Z direction can be, for example, the same thickness as that of the head portion 14 .

The neck portion 15 has a core portion 25 as a constituent element of the hard member 17 , and a soft portion 26 .

The core 25 has: a first part 25-1 extending along the X direction (extending direction of the neck 15) and penetrating the neck 15; Part 16 is part of the second part 25-2.

In addition, here, the 1st part 25-1 which comprises the neck part 15 is demonstrated, and the 2nd part 25-2 is demonstrated when the structure of the handle part 16 is demonstrated.

Fig. 8 is a cross-sectional view along line B-B of the hard component (specifically, the first part) shown in Fig. 4 . In FIG. 8 , the same reference numerals are assigned to the same structural parts as those in the structural body shown in FIGS. 1 to 6 . In addition, in FIG. 8, the code|symbol of the component of the toothbrush 10 other than the component of the hard member 17 is also shown for convenience of description. In FIG. 8, the symbol of the neck part 15 is shown for convenience of description.

1 to 6 and 8, one end of the first part 25-1 is formed integrally with the rear end of the base member 21, and the other end is formed integrally with the second part 25-2.

The first part 25-1 is made of hard resin. The first part 25-1 is made of a hard resin (a hard resin with a flexural modulus of elasticity (JIS K7203) in the range of 500 to 3000 MPa) than the second soft resin 27 constituting the first soft resin 22 and the soft portion 26. )constitute.

The first part 25-1 has the same thickness in the X direction. When a strong external force is applied to the tip of the head 14, the neck 15 is bent at the deformed portion 15A (for example, near the center of the neck 15) shown in FIG. 14), the thickness and shape of the first part 25-1 and the thickness of the soft part 26 disposed around the first part 25-1 may be determined.

Specifically, the area of the cut surface of the neck 15 (the area of the cut surface 25-1a of the first portion 25-1) obtained when the central portion of the neck 15 in the X direction is cut on a plane perpendicular to the X direction When the area S2 of the cut surface of S1 and the soft portion 26 is 100%, the area S1 of the cut surface 25-1a of the first part 25-1 is 5% or more and less than 50%, preferably 27% for example. %.

As the shape of the first portion 25 - 1 when cut on a plane perpendicular to the X direction, for example, a circle, an ellipse, a square, a rectangle, a rhombus, a star, or the like can be used. In addition, in consideration of the safety of the user, the corners of the first portion 25-1 are rounded (arc).

However, it is preferable that when using the toothbrush 10 to brush teeth, the neck 15 is difficult to deform (in other words, can be stably Press the tip of the bristle portion 12 against the teeth, interdental space, etc.).

Therefore, the first width W1 of the first part 25-1 on the Z direction (the first direction orthogonal to the flocking surface 21-1b) is larger than the first width W1 of the first part on the Y direction (second direction) orthogonal to the Z direction. The second width W2 needs to be as large as possible. The first width W1 is, for example, 1.5 mm to 3.0 mm, and the second width W2 is, for example, 1.5 mm to 2.0 mm.

In this way, the first width W1 of the first portion 25-1 in the Z direction is made larger than the second width W2 of the first portion in the Y direction, so that the cleaning performance of the toothbrush 10 is not degraded, and the cleaning performance of the toothbrush 10 can be reduced. When an external force is applied to the tip of the head portion 14, the deformed portion 15A is bent in the Y direction. Thereby, since the force applied to the tip of the head 14 can be released, damage to the oral cavity of the user of the toothbrush 10 can be suppressed.

In particular, when the user of the toothbrush 10 is an infant aged 1 to 3, there are cases where the toothbrush 10 is kept in the state of running, etc., but even if the infant falls in such a case, it is possible to Inhibits oral cavity damage in infants and young children.

As the cross-sectional shape of the first portion 25-1 in which the first width W1 of the first portion 25-1 in the Z direction is larger than the second width W2 of the first portion in the Y direction, an ellipse as shown in FIG. Rectangle, rhombus, etc. In this case, the ellipse includes not only a curve formed by a set of points whose sum of distances from two foci is constant, but also an elongated circle connecting two semicircles of the same radius by two parallel tangents.

When using the first part 25 - 1 formed in an elliptical or rhombus cross-sectional shape, it may be configured such that the maximum value of the first width W1 is greater than the maximum value of the second width W2 .

In addition, in FIG. 8, when the diameter R1 of the neck part 15 is 3.95 mm, the 1st width W1 can be 1.975 mm, for example. In this case, the second width W2 can be, for example, 1.7 mm.

The soft part 26 accommodates the first part 25 - 1 inside, and is composed of a second soft resin 27 that is softer than the hard resin constituting the core part 25 . The soft portion 26 suppresses the exposure of the first portion 25 - 1 , and is also a member for bending the deforming portion 15A of the neck 15 when a strong force is applied to the tip of the head 14 .

As the second soft resin 27 , for example, a soft resin having a Shore A hardness of 90 or less according to JIS K 6253 can be used. As such a soft resin, the soft resin exemplified in the description of the first soft resin 22 can be used.

The second soft resin 27 may be made of a different type of soft resin than the first soft resin 22 depending on the purpose. In this case, for example, the hardness of the soft resin used as the first soft resin 22 may be made higher than the hardness of the soft resin used as the second soft resin 27 . By setting it as such a structure, the hardness of the front-end|tip of the head part 14 and the hardness of the neck part 15 can be made different.

In addition, as the first and second soft resins 22 and 27, the same kind of soft resins may be used. Thereby, the number of kinds of soft resins used when manufacturing the toothbrush 10 can be reduced.

In FIG. 8 , as an example, the case where the outer shape of the cross section of the soft portion 26 is circular has been described, but the outer shape of the soft portion 26 is not limited thereto.

For example, in the case of using the first part 25-1 in which the cut plane 25-1a shown in FIG. -1a has an elliptical shape with the same major axis or the above-mentioned oblong shape. In addition, when the cut surface 25-1a is elliptical, oblong, or polygonal, the diameter R1 of the neck portion 15 may be set to a value corresponding to the circumscribed circle of the cut surface 25-1a.

Referring to FIGS. 1 to 6, the handle 16 has: a second part 25-2 (a part of the core 25) constituting the core 25; a plurality of protrusions 29 constituting the hard part 17; a handle main body 31; The recesses 32 - 1 , 32 - 2 (annular recesses); the first rib 34 ; the second rib 35 ; and the third rib 37 .

Fig. 9 is a cross-sectional view along line C-C of the hard member (specifically, the second part) shown in Fig. 4 . Fig. 10 is a cross-sectional view taken along line D-D of the hard member (specifically, the second part) shown in Fig. 4 .

In FIGS. 9 and 10 , the same components as those of the structures shown in FIGS. 1 to 6 are denoted by the same reference numerals. In FIGS. 9 and 10 , for convenience of explanation, the symbols of the handle 16 are shown. In addition, in FIG. 9 and FIG. 10, the code|symbol of the component of the toothbrush 10 other than the component of the handle part 16 is also shown in figure for convenience of description.

Referring to FIGS. 1 to 6, 9 and 10, the second part 25-2 is made of hard resin, and one end thereof is integrally formed with the first part 25-1. As the hard resin constituting the second portion 25-2, for example, the same hard resin as that constituting the first portion 25-1 can be used.

The second part 25-2 is configured as follows: in the X direction, as it goes from one end of the second part 25-2 to a plurality of columnar protrusions 29, the cross-sectional shape perpendicular to the X direction is continuously enlarged. similar shape. That is, it is configured such that the diameter of the portion provided with the plurality of protrusions 29 in the second portion 25-2 is the largest.

In addition, the portion of the second portion 25 - 2 that is disposed on the rear end side of the handle 16 with respect to the plurality of protrusions 29 has a shape that goes from the plurality of protrusions 29 to the rear end of the handle 16 . A cross-sectional shape perpendicular to the X direction is a similar shape in which the diameter continuously decreases.

In this way, the shape of the portion of the second portion 25 - 2 that is disposed on the rear end side of the handle 16 with respect to the plurality of protrusions 29 is set to increase from the plurality of protrusions 29 to the rear end of the handle 16 . side and the diameter becomes smaller. Therefore, for example, when using the same soft resin as the first and second soft resins 22 and 27, as shown in FIG. After the hard member 17, when the soft resin is introduced into the second mold 51 from the rear end side of the second mold 51, the soft resin tends to move (flow) in the direction (X direction) toward the tip of the head 14. Therefore, the whole hard member 17 can be accurately surrounded by soft resin (except for the flocking surface 21-1b and the plurality of flocking holes 21-1B).

In addition, as will be described later, when the above-mentioned soft resin is introduced into the second mold 51 , changes in the position and posture of the hard member 17 in the second mold 51 can be suppressed by the introduced soft resin.

In addition, as shown in FIG. 2 , the second part 25 - 2 is preferably built in the top end of the handle 16 , but is not limited thereto. The second part 25 - 2 can also be built in the neck 15 , for example.

In this embodiment, four protrusions 29 are provided as an example. The four protrusions 29 are arranged in the circumferential direction of the part with the thickest diameter in the second part 25-2.

The angle formed by the two protrusions 29 arranged at adjacent positions can be, for example, 90 degrees. The space formed between the two protruding portions 29 arranged at adjacent positions functions as a path for introducing the soft resin into the second mold 51 shown in FIG. 12 to be described later. The soft resin is supplied to the distal end side of the head portion 21 through this space, and is solidified (cured) to become the first soft resin 22 .

Each of the plurality of protrusions 29 has a protrusion surface 29a. The protruding surfaces 29a of the plurality of protruding portions 29 are exposed from the outer surface of the handle main body 31 (in other words, the outer surface of the handle 16), and are configured to be flush with the outer surface of the handle main body 31 (the outer surface of the handle 16). .

As shown in FIG. 1, FIG. 2 and FIG. 10, the protrusion part 29 which is a 1st protrusion part located in +Z side is exposed to the flocking surface 21-1b side through the opening part 31a of the shank part 31 (soft part 26). The protruding part 29 which is a 2nd protruding part located on the -Z side is exposed on the opposite side of the flocking surface 21-1b through the opening part 31b of the shank part 31 (soft part 26). The protruding portion 29 located on the +Y side is exposed on the +Y side through the opening portion 31c of the shank portion 31 (soft portion 26 ). The protruding portion 29 on the -Y side is exposed on the -Y side through the opening 31c of the shank 16 (soft portion 26 ). As shown in FIGS. 1 and 2 , the soft portion 26 of the shank 16 has a tapered tip portion 31A that tapers toward the tip side, and openings 31 a to 31 d are formed in the tapered tip portion 31A. In other words, the protruding portion 29 is exposed to the outside through the openings 31 a to 31 d formed in the tapered tip portion 31A of the shank 16 .

As shown in FIG. 10 , since the cross-sectional shape of the outer surface of the handle 16 is substantially circular, the cross-sectional shape of the protruding surface 29 a is arc-shaped. Therefore, each protruding surface 29a is exposed facing radially outward, and is exposed facing a direction perpendicular to the longitudinal direction and the radial direction of the toothbrush 10 . Specifically, for example, in FIG. 10 , the protruding surface 29 a of the protruding portion 29 as the first protruding portion on the +Z side is exposed facing the +Z side, and is exposed facing the +Y side and the −Y side. Similarly, for example, in FIG. 10 , the protruding surface 29a of the protruding portion 29 on the -Z side as the second protruding portion is exposed facing the -Z side, and is exposed facing the +Y side and the -Y side.

The plurality of protruding parts 29 have the following functions: using the second mold 51 (refer to FIG. 12 ), the hard member 17 is arranged in the space 53 of the second mold 51, and when the handle main body 31 is formed, the protruding surface 29a is aligned with the second mold. 51 to maintain the posture of the rigid member 17 in the space together with the two support portions 21 - 12 constituting the base member 21 (details will be described later). In the state where the hard member 17 is accommodated in the second mold 51, the protruding surfaces 29a of the four protrusions 29 contact the inner surface of the second mold 51, thereby supporting the rear end of the hard member 17 from four directions. .

The protrusion amount of the plurality of protrusions 29 is equal to the thickness of the second soft resin 27 arranged around the plurality of protrusions 29 . Therefore, the protrusion amount of the plurality of protrusions 29 can be appropriately adjusted so as to be flush with the surface of the second soft resin 27 according to the desired thickness of the second soft resin 27 arranged around the plurality of protrusions 29 . set up.

In FIG. 10, when the diameter R2 of the 2nd part 25-2 is 5.6 mm, the protrusion amount T1 of the several protrusion part 29 can be set as 1.77 mm, for example.

In addition, in FIGS. 1 to 6 and 10 , the case where four protrusions 29 are provided as an example of the plurality of protrusions 29 has been described as an example, but the number of the plurality of protrusions 29 is not limited to four.

For example, the number of the plurality of protrusions 29 may be, for example, three (in this case, the angle formed by the protrusions 29 disposed at adjacent positions may be 120 degrees), or may be two or more. less than one.

In addition, the shape of the plurality of protrusions 29 may be a shape having a flow path that allows the soft resin to flow from the rear end side of the plurality of protrusions 29 to the front end side of the base member 21. FIGS. The shape of the protruding portion 29 shown in FIG. 6 and FIG. 10 is not limited to a cylindrical shape. The cross-sectional shape of the plurality of columnar projections 29 may be, for example, a star shape, a heart shape, or the like, which are excellent in design.

Referring to FIGS. 1 to 3 , the handle main body 31 is a portion grasped by the user of the toothbrush 10 , and is made of the second soft resin 27 .

In this way, by constituting the handle body 31 with the second soft resin 27, when the toothbrush 10 is placed in the mouth, when a strong force is applied in the direction from the rear end of the toothbrush 10 to the top end of the head 14 When an external force is applied, the handle main body 31 can be deformed (specifically, bent).

Thus, not only the neck portion 15 is bent, but also the handle body 31 is bent, so that the external force from the rear end of the toothbrush 10 to the top end of the head 14 can be released in a direction different from this, and the oral cavity of the user of the toothbrush 10 can be suppressed. Internal damage.

In addition, by constituting the handle main body 31 using the second soft resin 27 , even when a strong force is applied to the handle main body 31 , damage to the handle 16 (in other words, breakage of the handle 16 ) can be suppressed.

The annular recesses 32 - 1 and 32 - 2 are provided annularly over the entire circumference of the handle main body 31 . The annular recess 32-1 is arranged on the rear end side of the handle 16 with respect to the arrangement position of the second portion 25-2. The annular recess 32 - 1 is formed by reducing the diameter of the shank body 31 . That is, in the annular recess 32 - 1 , the cross-sectional shape perpendicular to the X direction is similar to that of the shank body 31 and has a continuously decreasing diameter.

The arrangement position of the annular recess 32-2 with respect to the annular recess 32-1 is arranged on the rear end side of the handle 16, and is arranged at a distance of, for example, 20 mm to 50 mm. The annular recess 32 - 2 is formed by reducing the diameter of the handle main body 31 . That is, in the annular concave portion 32 - 2 , the cross-sectional shape perpendicular to the X direction is similar to that of the shank body 31 , and has a continuously decreasing diameter.

In this way, the ring-shaped recesses 32-1, 32-2 formed by reducing the diameter of the handle main body 31 are arranged in the X direction of the handle main body 31, so that when the toothbrush 10 is put in the mouth, When a strong external force is applied in the direction from the rear end of the toothbrush 10 to the top end of the head 14, the handle 16 will Can be bent easily.

Thereby, the external force applied in the direction from the rear end of the toothbrush 10 to the front end of the head 14 can be more efficiently released in a different direction, so that the user of the toothbrush 10 can further suppress damage to the oral cavity.

In addition, the annular recesses 32-1, 32-2 are formed by reducing the diameter of the handle body 31 in the X direction of the handle body 31, so that when the user uses the toothbrush 10, it is easy to hold the handle. 16, therefore, the operability of the toothbrush 10 can be improved.

In addition, in FIGS. 1 to 3 , the case where two annular recesses 32-1, 32-2 are provided in the handle main body 31 has been described as an example, but the annular recesses 32-1, 32-2 The number is not limited to two. The annular recesses 32 - 1 , 32 - 2 may be provided in the handle main body 31 at least one and at least five as necessary.

In addition, the disposition positions of the annular recesses 32-1, 32-2 only need to be provided on the handle main body 31 behind the disposition position of the second part 25-2, and are not limited to the rings shown in FIGS. 1 to 3 . The disposition positions of the shaped recesses 32-1, 32-2.

A plurality of first ribs 34 are arranged in a portion constituting a side surface (in other words, both side surfaces) of the handle main body 31 in the annular recess 32-1.

A plurality of second ribs 35 are arranged in a portion constituting a side surface (in other words, both side surfaces) of the handle main body 31 in the annular recess 32-2.

A plurality of third ribs 37 are arranged on the side surface (in other words, both side surfaces) of the handle main body 31 on the rear end side relative to the arrangement position of the second rib 35 .

The first to third ribs 34 , 35 , and 37 described above can be made of the second soft resin 27 . In this case, the first to third ribs 34 , 35 , 37 can be formed together when the handle main body 31 is formed.

In addition, the above-mentioned first to third ribs 34, 35, 37 are not necessarily essential, and may not be present.

In this way, since there are a plurality of first ribs 34 disposed in the annular recess 32-1, a plurality of annular recesses 32-2 disposed in the annular recess 32-2, and a plurality of ribs disposed in the second rib 35, A plurality of third ribs 37 on the side of the handle main body 31 at the rear end side make it difficult for fingers holding the toothbrush 10 to slip, thereby improving the grip performance of the handle main body 31 .

Referring to FIG. 1 , the bristle unit 12 is composed of a hair bundle 12 - 1 implanted in a plurality of hair planting holes 21 - 1B provided in the base member 21 . The hair bundle 12-1 is used to bundle a plurality of bristles.

The length (hair length) of the hair bundle 12-1 when using the hair-implanted surface 21-1b as a reference can consider the hair hardness etc. required for the hair bundle 12-1, and can be determined. Specifically, the length (hair length) of the hair bundle 12-1 can be set suitably within the range of 6-13 mm, for example.

The hair bundle 12 - 1 may be composed of, for example, a plurality of bristles having the same hair length, or may be composed of a plurality of bristles having different hair lengths.

In FIG. 1, as an example of the bristle part 12 which comprises the toothbrush 10, the case where the front-end|tip of the several hair bundle 12-1 which comprises the bristle part 12 was shown as an example was shown, but it is not limited to this.

For example, a level difference may be provided in the bristle part 12 by making the length of the some hair bundle 12-1 which comprises the bristle part 12 different.

The thickness (hair bundle diameter) of the hair bundle 12-1 can consider and determine the hair hardness etc. required for the hair bundle 12-1, For example, it can set suitably within the range of 1-2 mm.

All the hair bundles 12-1 may have the same hair bundle diameter or may be different from each other.

As a plurality of bristles constituting the hair bundle 12-1, for example, tapered bristles whose tip diameter becomes smaller toward the bristle tip, straight bristles whose diameter is substantially the same from the hair-implanting surface 21-1b toward the tip, can be used. Shape hair etc.

In addition, as the straight hair, for example, bristles whose hair tips are flat surfaces substantially parallel to the hair-implanted surface 21-1b, or bristles whose hair tips are trimmed into a hemispherical shape can be used.

The material of the bristles constituting the hair bundle 12-1, for example, 6-12 nylon (6-12NY), polyamide such as 6-10 nylon (6-10NY), PET, PBT, polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN) and other polyester fibers, and resin materials such as polyolefins such as PP.

The said resin material which is a material of a bristle may be used individually by 1 type, or may be used in combination of 2 or more types.

In addition, as the bristles constituting the bristle bundle 12-1, for example, bristles made of polyester having a core and at least one or more sheaths provided outside the core may be used in a multi-core structure.

The cross-sectional shape of the bristles constituting the hair bundle 12-1 is not particularly limited, and for example, a circle such as a perfect circle or an ellipse, a polygon, a star, a clover, or a four-leaf clover can be used.

The cross-sectional shapes of all the bristles constituting the bristle portion 12 may be the same or different.

The thickness of the bristles constituting the bristle bundle 12-1 can be determined in consideration of the material of the bristles and the like. When the cross section of the bristles is circular, the thickness of the bristles can be set to, for example, 6 to 9 mils. In addition, 1mil is 0.0254mm.

In addition, considering the usability, brushing feeling, cleaning effect, durability, etc., the hair bundle 12-1 can be composed of arbitrarily combining a plurality of bristles with different thicknesses.

The toothbrush according to this embodiment has: a head 14, at least the top end of which is made of a first soft resin 22, and has a flocking surface 21-1b; a handle 16 including a handle body made of a second soft resin 27 31; and the neck 15, connecting the head 14 and the handle 16, the neck 15 has: a core 25, extending along the extension direction (X direction) of the neck 15, and made of a hard material harder than the first soft resin 22 and the soft part 26 accommodates the core part 25 inside and is made of a second soft resin 27 softer than the hard resin, so that when the user puts the toothbrush 10 in the mouth, When a strong external force is applied in the direction from the rear end of the toothbrush 10 to the top of the head 14, the neck 15 and the handle 16, which take the second soft resin 27 as structural elements, are deformed (specifically, bent). ), so that the force transmitted to the tip of the head 14 can be released, and the softer first soft resin 22 arranged at the tip of the head 14 can be brought into contact with the user's oral cavity, so the toothbrush 10 can be suppressed Damage to the user's oral cavity.

In particular, when the user of the toothbrush 10 is an infant aged 1 to 3, there is a case of running while keeping the toothbrush 10 in the mouth, but even when the infant falls under such circumstances, It can also suppress oral cavity damage in infants and young children.

In addition, in this embodiment, the case where the hard member 17 which has the base member 21, the core part 25, and several protrusion parts 29 was used as the structural element of the toothbrush 10 was demonstrated as an example, but for example, you may use A toothbrush (hereinafter, referred to as "toothbrush Q" for convenience of description) is constituted by a hard part (hereinafter, referred to as "hard part P" for convenience of description) after the base member 21 is removed from the structural elements. In this case, the same effect as toothbrush 10 of this embodiment can be acquired.

In this case, the hard member P may be configured not only on the rear end side of the core portion 25 but also on the front end side of the core portion 25 .

With such a structure, when the soft resin (resin as the first and second soft resins 22 and 27) is introduced into a mold (not shown) having a space corresponding to the outer shape of the toothbrush Q, the mold can be held. Since the posture (position) of the inner hard member P is controlled, the toothbrush Q can be manufactured with high precision.

In addition, when manufacturing the toothbrush Q (specifically, when implanting hair bundles), an in-mold injection method may be used.

Fig. 11 is a cross-sectional view showing a manufacturing process of the toothbrush according to the present embodiment, and is a diagram for explaining a process of forming a hard member using a first die. 12 is a cross-sectional view showing the manufacturing process of the toothbrush according to this embodiment, and is a diagram for explaining a process of forming the first soft resin, the soft part, and the handle main body using the second mold.

In FIGS. 11 and 12 , the same components as those of the structures shown in FIGS. 1 to 10 are denoted by the same reference numerals. The arrows shown in FIG. 11 indicate the direction in which the hard resin is introduced, and the arrows shown in FIG. 12 indicate the direction in which the soft resin (soft resin N described later) is introduced.

Next, the manufacturing method of the toothbrush 10 of this embodiment is demonstrated mainly with reference to FIG.1, FIG.11, and FIG.12.

In addition, here, the case where the same kind of soft resin (hereinafter referred to as "soft resin N") is used as the first and second soft resins 22 and 27 will be described as an example.

First, in the process shown in FIG. 11 , the first mold 41 is prepared. The first mold 41 is composed of a pair of molds 41 - 1 , 41 - 2 and has a space 43 corresponding to the shape of the hard member 17 inside. , and an introduction port 45 for introducing hard resin into the space 43 .

A protruding part (not shown) for forming a plurality of tufting holes 21-1B is formed in the mold 41-2. In addition, the introduction port 45 is arranged on the rear end side of the space 43 .

Next, through the inlet 45, the space 43 is filled with molten hard resin (resin having a flexural modulus of elasticity (JIS K7203) in the range of 500 to 3000 MPa) serving as the base material of the hard member 17, and the hard resin By curing, the base member 21 including the plurality of tufting holes 21-1B and the support portion 21-2, the core portion 25, and the plurality of protruding portions 29 are integrally formed into the hard member 17. After that, the hard part 17 is taken out from the first mold 41 .

Next, in the process shown in FIG. 12, the second mold 55 is prepared. This second mold 55 is composed of a pair of molds 51-1, 51-2, and has the toothbrush with the bristle portion 12 shown in FIG. 1 removed. The shape of 10 corresponds to the space 53 and the inlet 55 for introducing hard resin into the space 53 . The joining surfaces of the pair of dies 51-1, 51-2 are set, for example, at intermediate positions in the Z direction of the soft part 26 (handle main body 31) shown in FIGS. 8 to 10 .

A protrusion (not shown) for forming a plurality of tufting holes 21-1B is formed in the mold 51-2. In addition, the introduction port 55 is arranged on the rear end side of the space 53 .

In addition, the second die 51 is provided with protrusions for forming the annular recesses 32 - 1 , 32 - 2 , the first rib 34 , the second rib 35 , and the third rib 37 shown in FIG. 1 .

Next, the hard member 17 is disposed at the tip end portion of the space 53 of the second mold 51 . At this time, the inner surface of the mold 51-2 is brought into contact with the tufting surface 21-1b so as to cover a plurality of tufting holes 21-1B, and the end surfaces of the two supporting parts 21-2 are brought into contact with the inner surface of the mold 51-1. In contact, further, the protruding surfaces 29 a of the plurality (four in the present embodiment) of the protruding portions 29 are brought into contact with the inner surface of the second die 51 .

Thus, when introducing the soft resin N as the first soft resin 22 and the second soft resin 27 (the soft resin constituting the soft portion 26 and the handle main body 31 ) into the space 53 of the second mold 51 , the position and posture of the hard member 17 in the second die 51 can be maintained.

That is, the protruding surface 29a of the protruding portion 29 on the +Z side is in contact with the inner surface of the mold 51-2, and the protruding surface 29a of the protruding portion 29 on the -Z side is in contact with the inner surface of the mold 51-1, so that the hard part 17 is positioned in the Z direction. In addition, both the protruding surface 29a of the protruding portion 29 on the +Z side and the protruding portion 29 on the -Z side face the +Y side and the -Y side, so they pass through the inner surfaces of the mold 51-1 and the mold 51-2. It is also positioned in the Y direction.

In addition, the end surfaces of the two supporting parts 21-2 and the protruding surfaces 29a of the plurality of protruding parts 29 are in contact with the inner surface of the second die 51, so that it is possible to securely form a solid body for forming between the hard member 17 and the second die 51. The gap between the first soft resin 22 and the soft part 26 .

Next, molten soft resin N (resin having a Shore A hardness of JIS K 7215 of 90 or less) is filled into the space 53 through the introduction port 55 .

The distance between the inner surfaces of the die 51 - 1 and the die 51 - 2 at the position corresponding to the narrowed tip portion 31A becomes shorter so that the tip becomes thinner toward the tip side, and the inner surface contacts the protruding surface 29 a to prevent The hard member 17 moves toward the distal end side. Therefore, even if the resin pressure of the molten soft resin N filled through the inlet 55 is applied, the hard member 17 is positioned without moving in the X direction.

Thereafter, by curing the soft resin N, the first soft resin 22 , the soft portion 26 , and the handle main body 31 are formed. On the surface of the soft part 26 at a position (approximately in the middle position in the Z direction) facing the joining surface of the mold 51-1 and the mold 51-2, a parting line of a fine protrusion is formed.

Thus, the handle body 11 having the head 14 , the neck 15 and the handle 16 is formed. After that, the handle body 11 is taken out from the second mold 51 .

Next, as shown in FIG. 1 , hair bundles 12 - 1 are planted in the plurality of hair planting holes 21 - 2 of the head 11 . Thereby, the toothbrush 10 of this embodiment shown in FIG. 1 is manufactured.

As the hair-planting method of the hair bundle 12, for example, the following flat-wire type hair-planting can be used: After the hair bundle 12-1 is folded in half, a flat wire (made of metal (such as brass) with a thinner thickness) is sandwiched inside the hair bundle 12-1. Thin plate), the hair bundle 12-1 sandwiching the flat wire is planted in the hair-planting hole 21-2.

In addition, in the present embodiment, the case of using flat wire type hair transplanting as the hair transplanting method of the hair bundle 12-1 has been described as an example, but instead of this method, for example, the following method may be used: the hair bundle 12-1 The thermal welding method in which the lower end is pressed into the resin (soft resin or hard resin) constituting the head 14 and fixed, and the molten resin is introduced into the mold after heating the lower end of the hair bundle 12-1 to form a molten mass. Injection molding, etc.

As above, preferred embodiments of the present invention have been described in detail, but the present invention is not limited to the specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Deformation, change.

For example, in the above-mentioned embodiment, the structure in which the soft part 26 is provided at the tip of the head 14 is exemplified, but it is not limited thereto. As shown in the side view of FIG. 13 and the front view of FIG. A structure in which the deformed portion 15A of the neck portion 15 is included and the soft portion 26 is provided toward the rear end side from the deformed portion 15A.

In addition, as a toothbrush, the present invention can be widely applied to a so-called single-tuft toothbrush having one bristle bundle, a toothbrush having a tongue coating removal assisting portion, and the like.

In addition, in the above-mentioned embodiment, between the flocking surface 21-1b and the shank 16, the neck portion whose width in the second direction (Y direction) is smaller than the width of the head 14 (maximum width in the Y direction) is arranged. The toothbrush 10 of 15 has been described, but is not limited to this structure, for example, the toothbrush under the situation that the width of Y direction is the same as the maximum width of head 14 exists between flocking surface 21-1b and handle 16 also included in the present invention. In this case, the portion serves as a neck, and a deformed portion is arranged, and at least a part of the hard member is housed inside from the deformed portion toward the rear end side, and a soft portion made of soft resin is arranged.

Industrial availability

This invention can be used for the toothbrush which suppresses damage to a user's oral cavity.

Symbol Description

10...Toothbrush, 11...Handle body, 12...Bristle part, 14...Head, 15...Neck, 15A...Deformation part, 16...Handle, 17...Hard part, 21...Base part, 21-1... Base member main body, 21-1a... bottom surface, 21-1A... top end, 21-1b... flocking surface (first exposed part), 21-1B... flocking hole, 21-2... supporting part, 21-2a... protruding Surface, 22...the first soft resin, 25...the core, 25-1...the first part, 25-1a...the cut surface, 25-2...the first part, 26...the soft part, 27...the second soft part Resin, 29...protruding part, 29a...protruding surface, 31...shank main body, 31A...tip tapering part, 32-1, 32-2...annular concave part (second deformation part), 34...first rib part, 35 ... second rib, 37 ... third rib, 41 ... first mold, 41-1, 41-2, 51-1, 51-2 ... mold, 43, 53 ... space, 45, 55 ... inlet, 51...second die, R1, R2...diameter, S1, S2...area, T1...projection amount, W1...first width, W2...second width.

Claims (14)

1. A toothbrush, characterized in that, has: a head having a flocking surface on the tip side; and a handle that is disposed on the rear end side relative to the head and includes a handle main body, The toothbrush includes: a deformation part, the deformation part is arranged between the flocking surface and the handle, and is deformed by an external force applied to the head; a hard member arranged from the head over a part of the top end side of the handle and formed of hard resin; and The soft part is disposed toward the rear end side from the deformation part, accommodates at least a part of the hard member inside, and is formed of a soft resin. 2. The toothbrush according to claim 1, characterized in that it has: a second deforming portion disposed on the handle and deformed by the external force. 3. (Content of the old claim 3 and the second deformation part) The toothbrush according to claim 2, characterized in that The shank has at least one annular recess with reduced diameter in the extending direction of the shank, The second deformation portion is disposed at a position where the recess is disposed. 4. The toothbrush according to any one of claims 1-3, characterized in that, The said hard member has a 1st exposed part exposed to the side of the said flocking surface in the said head part, and a 2nd exposed part exposed to the side opposite to the said flocked surface. 5. The toothbrush according to any one of claims 1-4, characterized in that, The hard part has a columnar first protrusion and a columnar second protrusion, the first protrusion protrudes and is exposed toward the flocking surface side at the handle, and the second protrusion is at the handle It protrudes and exposes to the opposite side of the flocking surface. 6. The toothbrush according to claim 5, characterized in that, The first protruding portion is exposed through a first opening formed on the flocking surface side of the soft portion, The second protruding portion is exposed through a second opening formed on a side opposite to the flocking surface side of the soft portion. 7. The toothbrush according to claim 6, characterized in that, The soft part of the shank has a tapered tip portion that tapers toward the tip side, The first opening and the second opening are formed in the narrowed-end portion. 8. The toothbrush according to any one of claims 5-7, characterized in that, The soft part has a parting line on the surface, The first protruding portion is exposed to one side in a direction perpendicular to the flocking surface across the parting line, The second protruding portion is exposed to the other side in the perpendicular direction across the parting line. 9. (content of old claim 5) according to any one of claim 5-8 toothbrush, it is characterized in that, the rigid member is configured to extend to the handle, The top surface of the first protrusion and the top surface of the second protrusion are flush with the outer surface of the handle. 10. (Content of the old claim 6) The toothbrush according to any one of claims 5-9, characterized in that, A portion of the hard member disposed on the rear end side of the shank relative to the first protrusion and the second protrusion has a diameter that becomes smaller toward the rear end side of the shank. shape. 11. (Part of old claim 1) A toothbrush according to any one of claims 1-10, characterized in that At least the top end of the head is made of a first soft resin that is softer than the hard resin, The handle body is made of a second soft resin that is softer than the hard resin, The soft portion is made of the second soft resin. 12. (Content of old claim 2) The toothbrush according to any one of claims 1-11, characterized in that The first width of the hard part in the first direction between the flocking surface and the handle is larger than the second width in the second direction, the first direction is orthogonal to the flocking surface, the The second direction is perpendicular to the length direction of the handle and the first direction. 13. (Content of old claim 4) The toothbrush according to any one of claims 1-12, characterized in that, The hard part of the head comprises the flocking surface and a base part with a plurality of flocking holes, The first soft resin is arranged to cover a part of the base member in a state where the flocking surface and the plurality of flocking holes are exposed. 14. The toothbrush according to any one of claims 1-13, characterized in that, A neck is disposed between the flocking surface and the shank, the width of the neck in the second direction is below the width of the head, and the width of the second direction is the same as that of the first direction and the shank. The length direction is orthogonal, and the first direction is orthogonal to the flocking surface.