TW201909790A - toothbrush - Google Patents

Abstract

The object of the present invention is to provide a toothbrush including a handle portion having high grip properties without an increase in cost. The handle portion (30) includes a first expanding portion (41) in which the maximum length in the width direction is at a first position (P1) in the longitudinal direction, a first constriction portion (43) in which the minimum length is at a second position (P2) that is positioned closer to an end side than the first expanding portion, a second expanding portion (42) in which the maximum length is at a third position (P3) that is positioned closer to the end side than the first constriction portion, and a second constriction portion (44) in which the minimum length is at a forth position (P4) that is positioned closer to the end side than the second expanding portion. When the minimum length of the first constriction portion is PW2 and the maximum length of the second expanding portion is PW3, PW3 is 15 mm or more and 20 mm or less and PW3/PW2 is 1.3 or more and 1.5 or less. When the thickness of the first position is PT1 and the thickness of the third position is PT3, PT3 is 15 mm or more and 20 mm or less and PT3/PT1 is 1.7 or more and 2.5 or less.

Description

toothbrush

The invention relates to a toothbrush. This application is based on Japanese Patent Application No. 2017-147972 filed in Japan on July 31, 2017 and claims priority, and the contents are cited in this application.

In the past, in order to achieve oral cleaning in various corners, attention was paid to the operability in the oral cavity, and the miniaturization of the hair-planting part was usually carried out. However, in the case of oral cleaning using a small hair-planting part, skill in the cleaning method or cleaning time is required. Therefore, a toothbrush having a type of head (wide head) that enlarges the hair-planting portion has been developed, but it has been pointed out that it is difficult for the bristle portion to reach the cleaning site properly because the hair-planting portion has a wide design.

Patent Literature 1 discloses a wide-head toothbrush with high-definition sweeping ability that can simultaneously sweep a plurality of cleaning sites by intensively studying the type or arrangement of bristles. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2016-209616

[Problems to be Solved by the Invention] However, in the conventional toothbrush of the conventional wide-head specification described above, although the cleaning performance is improved to a certain extent, the interference of the hair bundle when contacting the cleaning site is large. Therefore, there is a possibility that the grip portion is shaken and hinders stable cleaning. In order to improve the handleability and slip resistance of the handle to improve the grip, for example, it is also considered to provide a soft portion such as rubber on the surface of the handle.

However, in the above-mentioned case, it is not only necessary to use a variety of resins, but also to produce the handle by two-color molding or the like, which causes a problem of increased cost. This kind of problem is not limited to wide head specifications, but may also occur in small-size heads.

The present invention is made in consideration of the above-mentioned aspects, and an object of the present invention is to provide a toothbrush having high gripping ability on a handle without increasing costs. [Means to solve the problem]

According to a first aspect of the present invention, there is provided a toothbrush, comprising: a head, which is arranged on the front end side in the long axis direction and has hair bundles planted on the hair-planting surface; and a neck, which is extended to the head The rear end side; and the handle portion, which extends on the rear end side of the neck portion, and the handle portion has: a first bulging portion, which is arranged on the rear end side of the neck portion, and is free from the hair transplant When viewed from the front in a direction perpendicular to the plane, it swells continuously and symmetrically on both sides in the width direction orthogonal to the long axis direction and the front direction; the first tapered portion is arranged on the first 1 The rear end side of the bulging portion continuously changes symmetrically on both sides in the width direction and becomes thin; the second bulging portion is disposed on the rear end side of the first narrowing portion, The width direction continuously changes symmetrically on both sides and bulges; and the second tapered portion is disposed on the rear end side of the second bulge portion and continuously symmetrically on both sides in the width direction Changes and becomes thinner, the first bulging portion is between the neck portion in the long axis direction and the first thinning portion In the first position, the length in the width direction becomes the largest, and the first tapered portion is in the second position between the first bulging portion and the second bulging portion in the long axis direction , The length in the width direction becomes the smallest, the second bulge is at a third position between the first tapered portion and the second tapered portion in the long axis direction, the width direction The length becomes the largest, the second tapered portion is at the fourth position on the rear end side of the second bulge in the long axis direction, the length in the width direction becomes the smallest, if the The width direction length of the first tapered portion at the second position is PW2, and the width direction length of the second bulging portion at the third position is PW3, then The PW3 is 15 mm or more and 20 mm or less, and the PW3 / PW2 is 1.3 or more and 1.5 or less. If the thickness in the front direction at the first position is PT1, and the When the thickness in the front direction is PT3, the PT3 is 15 mm or more and 20 mm or less, and PT3 / PT1 is 1.7 or more and 2.5 or less.

In addition, in the toothbrush according to one aspect of the present invention, the first swelled portion, the first tapered portion, the second swollen portion, and the second tapered portion are each composed of The front-view contour line is formed by a curve that circumscribes the adjacent bulge or tapered portion in the long axis direction.

In addition, in the toothbrush according to one aspect of the present invention, the cross-sectional shape of the handle at the first position is a flat shape in which the length in the width direction is greater than the thickness in the front direction, and The cross-sectional shape of the shank at the third position is substantially circular.

In addition, in the toothbrush according to one aspect of the present invention, at least one of the front side and the back side of the handle at the first position has a groove.

In addition, in the toothbrush according to one aspect of the present invention, the groove portion is formed in a ring shape.

In addition, in the toothbrush according to one aspect of the present invention, the maximum length of the head in the width direction is 13 mm or more. [Effect of invention]

In the present invention, it is possible to provide a toothbrush having a high grip for the handle without increasing the cost.

Hereinafter, the embodiment of the toothbrush of the present invention will be described with reference to FIGS. 1 to 7. In the present embodiment, an example of a toothbrush with a wide-head specification in which the width of the head is enlarged will be described.

In addition, the following embodiment shows an embodiment of the present invention, does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. In addition, in the following drawings, in order to facilitate understanding of each structure, the actual structure is different from the scale, number, etc. in each structure.

FIG. 1 is a front view of the toothbrush 1. FIG. 2 is a side view of the toothbrush 1. FIG. 3 is a back view of the toothbrush 1.

The toothbrush 1 of this embodiment includes a head 10, which is arranged on the front end side in the long axis direction (hereinafter, referred to as the front end side) and has a tuft (not shown) in which hair is planted with toothbrush hairs; The rear end side of the long axis direction of the portion 10 (hereinafter, simply referred to as the rear end side); and the handle portion 30 extending on the rear end side of the neck portion 20 (hereinafter, the head portion 10 is joined to the neck portion 20 and the handle portion 30) Called the handle body 2).

The head 10 has a tufted surface 11 on one side in the thickness direction. Furthermore, in the thickness direction, the flocked surface 11 side is referred to as the front side in the front direction, the opposite side of the flocked surface 11 is referred to as the back side, and the direction orthogonal to the front direction and the long axis direction is provided Is the width direction. In the following description, the thickness in the front direction is simply referred to as thickness. A plurality of hair-planting holes 12 are formed on the hair-planting surface 11. A hair bundle (not shown) with toothbrush hairs is planted in the hair-planting hole 12.

The head 10 is a wide-width wide-head specification. The maximum width W1 of the head 10 is 13 mm or more and 16 mm or less. The length of the head 10 is not particularly limited. For example, it is preferably 10 mm or more and 33 mm or less. If the length of the head 10 is equal to or greater than the lower limit, the area where the hair bundle is implanted can be sufficiently secured, and if it is equal to or less than the upper limit, the operability in the oral cavity can be further improved.

Among the plurality of hair-planting holes 12, the distance from the hair-planting hole 12 located on the foremost side of the head 10 to the front end of the head 10 and the hair-planting hole 12 located on the rearmost side of the head 10 to the rear end of the head 10 The distance is set equal. In other words, if the distance from the hair transplant hole 12 located on the most front end side of the head 10 to the front end of the head 10 is d, the boundary position of the head 10 and the neck 20 is on the rear end side and the head 10 The planting holes 12 on the rearmost side of the are separated by a distance equal to the distance d.

The thickness of the head 10 can be determined in consideration of the material of the handle body 2 and the like, preferably 2.0 mm or more and 6.0 mm or less, and more preferably 3.0 mm or more and 5.0 mm or less. If the thickness is above the lower limit, the strength of the head 10 can be further increased, and if the thickness is below the upper limit, the reachability to the deep part of the molar can be improved, and the operation in the oral cavity can be further improved Sex.

Since the neck 20 contacts the lips when the head 10 is inserted into the oral cavity, the length of the neck 20 is preferably 40 mm or more and 70 mm or less. The minimum width and minimum thickness of the neck portion 20 are preferably 3.0 mm or more and 6.0 mm or less, for example. If it is above the lower limit, the strength of the neck 20 can be further improved, and if it is below the upper limit, the lips can be easily closed, and the reachability to the molars can be improved, and it can be further improved in the oral cavity. Operability. In addition, as described later, the boundary between the neck 20 and the handle 30 has a front boundary 31 and a rear boundary 32 (see FIG. 5), but the rear end side when calculating the length of the neck 20 The position of the front side of the border 31 is used.

As shown in FIG. 2, both the front side and the back side of the neck 20 extend substantially parallel to the tufted surface 11. The front side of the neck portion 20 has an arc-shaped curved profile 21 having a polar center on the front side when viewed from the side and gradually facing upward (front side) as it goes toward the rear end side. The back side of the neck portion 20 has an arc-shaped curved contour 22 having a polar center on the back side when viewed from the side and gradually facing downward (back side) as it goes toward the rear end side.

As shown in the front view of FIG. 1 and the back view of FIG. 3, the handle portion 30 has a first bulging portion 41 and a second bulging portion 42 that have a width in the width direction that continuously changes symmetrically on both sides and swells. The lengths in the direction continuously change symmetrically on both sides and become thinner, the first tapered portion 43 and the second tapered portion 44, and the through-hole 46 disposed near the rear end. The first bulging portion 41, the first tapering portion 43, the second bulging portion 42, and the second tapering portion 44 are arranged in this order from the front end side along the long axis direction. In addition, a groove portion 45A is formed on the front side of the handle portion 30, and a groove portion 45B is formed on the rear side of the handle portion 30.

The first bulging portion 41 has the largest length in the width direction at the first position P1 on the tip side in the long axis direction. The first position P1 is a position where the length in the width direction of the first bulging portion 41 becomes the largest between the neck portion 20 and the first tapered portion 43 in the long axis direction. The first tapered portion 43 has a minimum length in the width direction at the second position P2 disposed on the rear end side of the first position P1 in the long axis direction. The second position P2 is a position between the first bulging portion 41 and the second bulging portion 42 in the long axis direction, and the widthwise length of the first tapered portion 43 becomes the smallest. The second bulging portion 42 has the largest length in the width direction at the third position P3 disposed on the rear end side of the second position P2 in the long axis direction. The third position P3 is a position between the first tapered portion 43 and the second tapered portion 44 in the long axis direction where the length of the second bulging portion 42 in the width direction becomes the largest. The second tapered portion 44 has a minimum length in the width direction at the fourth position P4 disposed on the rear end side of the third position P3 in the long axis direction. The fourth position P4 is a position on the rear end side of the third position P3 in the long axis direction, and the length of the second tapered portion 44 in the width direction becomes the smallest. That is, it is a position where a curve or a straight line forming both edges whose width is narrowed from the third position P3 changes to a curve or a straight line whose width is wide, or a straight line having the same width.

The first bulging portion 41, the first tapering portion 43, the second bulging portion 42 and the second tapering portion 44 are circumscribed with the adjacent bulging portion or the tapering portion in the long axis direction by the respective frontal contour lines Smooth curve is formed.

Specifically, the first bulging portion 41 has an arc-shaped curved contour C1 having a center of curvature on the center side in the width direction when viewed from the front. The first tapered portion 43 has an arc-shaped curved profile C2 having a center of curvature on the outer side in the width direction when viewed from the front. The second bulging portion 42 has an arc-shaped curved contour C3 having a center of curvature on the center side in the width direction when viewed from the front. The second tapered portion 44 has an arc-shaped curved contour C4 having a center of curvature on the outer side in the width direction when viewed from the front. Each curve profile C1 to curve profile C4 circumscribes the adjacent curve profile in the long axis direction.

Regarding the handle portion 30, if the length in the width direction of the first bulging portion 41 (the width of the first position P1) is PW1, and the length in the width direction of the first tapered portion 43 (the width of the second position P2) is set PW2, the width direction length of the second bulging portion 42 (the width of the third position P3) is PW3, and the length direction width of the second tapering portion 44 (the width of the fourth position P4) is PW4, Then the following relationship (1) and relationship (2) are satisfied respectively. PW3> PW1> PW2… (1) PW3> PW4> PW2… (2)

The width PW1 of the first position P1 is preferably 14 mm or more and 17 mm or less. The width PW2 of the second position P2 is preferably 11 mm or more and 14 mm or less. The width PW3 of the third position P3 is preferably 15 mm or more and 20 mm or less. The width PW4 of the fourth position P4 is preferably 12.5 mm or more and 15.5 mm or less. The difference between the widths of the first position P1 and the second position P2 (PW1-PW2) is preferably 2.5 mm or more and 3.5 mm or less. The difference between the widths of the third position P3 and the second position P2 (PW3-PW2) is preferably 4 mm or more and 5.5 mm or less. The difference between the widths of the fourth position P4 and the second position P2 (PW4-PW2) is preferably 0.5 mm or more and 1.5 mm or less. PW3 / PW2 is preferably 1.3 or more and 1.5 or less.

As shown in FIG. 2, the front side of the handle 30 has: an arc-shaped curved profile C11 arranged at the first position P1 and having a center of curvature on the front side when viewed from the side; and arranged at the second position P2 and viewed from the side Arc-shaped curved contour C12 having a center of curvature on the front side; arc-shaped curved contour C13 disposed on the third position P3 and having a center of curvature on the back side; disposed on the fourth position P4 when viewed from the side An arc-shaped curved contour C14 having a center of curvature on the front side; and a circular arc-shaped curved contour C15 having a center of curvature on the back side when circumscribed to the curved contour C12 and the curved contour C13, respectively, when viewed from the side. The curve profiles C12 to C15 are circumscribed with the adjacent curve profiles in the long axis direction.

As shown in FIG. 2, the back side of the handle 30 has: an arc-shaped curved profile C21 arranged at the first position P1 and having a center of curvature on the back side when viewed from the side; and arranged at a second position P2 and viewed from the side Arc-shaped curved contour C22 having a center of curvature on the front side; arc-shaped curved contour C23 having a center of curvature on the front side when disposed at the third position P3; and side view when disposed at the fourth position P4 An arc-shaped curved profile C24 having a center of curvature on the back side; and a circular arc-shaped curved profile C25 having a center of curvature on the front side when circumscribed to the curved profile C22 and the curved profile C23, respectively, and viewed from the side. The curve contours C22 to C25 are circumscribed with the adjacent curve contours in the long axis direction.

Regarding the handle portion 30, if the thickness of the first position P1 is PT1, the thickness of the second position P2 is PT2, the thickness of the third position P3 is PT3, and the thickness of the fourth position P4 is PT4, Then the following relationship (3) and relationship (4) are satisfied respectively. PT3> PT2> PT1… (3) PT3> PT4> PT1… (4)

The thickness PT1 of the first position P1 is preferably 6.5 mm or more and 9 mm or less. The thickness PT2 of the second position P2 is preferably 9 mm or more and 11 mm or less. The thickness PT3 of the third position P3 is preferably 15 mm or more and 20 mm or less. The thickness PT4 of the fourth position P4 is preferably 10 mm or more and 13 mm or less. The difference between the thicknesses of the first position P1 and the second position P2 (PT2-PT1) is preferably 1.5 mm or more and 3.0 mm or less. The difference between the thicknesses of the first position P1 and the third position P3 (PT3-PT1) is preferably 5.5 mm or more and 9 mm or less. The difference between the thicknesses of the first position P1 and the fourth position P4 (PT4-PT1) is preferably 2.5 mm or more and 4.5 mm or less. PT3 / PT1 is preferably 1.7 or more and 2.5 or less.

In addition, the distance between the first position P1 and the third position P3 is preferably 30 mm or more and 60 mm or less. When the distance between the first position P1 and the third position P3 is lower than the lower limit value, when the handle 30 is held, the distance between the first position P1 and the third position P3 becomes shorter and abuts on the second position The distal section of the thumb of the front side of P2 is close to the index finger that is in the circumferential direction of the second position P2, and the auxiliary function when the load is applied to the head 10 during cleaning may decrease, and it is difficult to distinguish the first position P1 from the tactile sense The third position P3. When the distance between the first position P1 and the third position P3 exceeds the upper limit, when the handle 30 is held, the distance between the first position P1 and the third position P3 becomes longer, and the front of the first position P1 The side is the finger contact portion of the distal thumb joint, and it may be difficult to keep the middle finger and the ring finger in the circumferential direction at the third position P3.

4 is a cross-sectional view of the shank 30 cut at the first position P1. As shown in FIG. 4, the cross-sectional shape of the shank portion 30 (first bulging portion 41) at the first position P1 is a flat shape whose length in the width direction is greater than the thickness. On the front side of the shank portion 30, a front-view circular groove portion 45A formed in a ring shape with the center in the width direction of the first position as the center is provided. On the back side of the handle portion 30, a front-view circular groove portion 45B formed in a ring shape with the center of the first position in the width direction as a center is provided.

In addition, as shown in FIG. 4, the front side of the shank 30 has an arc-shaped curved profile C31 having a center of curvature on the back side with respect to the width direction. The curved profile C31 has groove portions 45A on both sides, and the height T1 is formed with a low-order difference of 0.5 mm to 1.5 mm. Similarly, the back side of the shank 30 has an arc-shaped curved profile C32 having a center of curvature on the front side with respect to the width direction. The curved profile C32 has groove portions 45B on both sides, and the height T2 is formed with a low-order difference of 0.5 mm to 1.5 mm.

FIG. 5 is an enlarged side view of the first position P1 in FIG. 2. The boundary 31 between the neck 20 and the handle 30 on the front side is a portion where the curved contour 21 disposed on the front end side of the boundary 31 and the curved contour C11 disposed on the rear end side of the boundary 31 intersect in a side view. Formed by the ridgelines. The position of the boundary 31 in the front direction, that is, the position where the curved contour C11 and the curved contour 21 cross is arranged on the front side of the position where the curved contour C11 and the curved contour C12 cross. Therefore, as compared with the rear end side of the first position P1 on the front side, a sharply curved surface is formed on the front end side of the first position P1.

Regarding the front end side in the long axis direction, the height T3 of the groove 45A is formed with a step difference of 0.5 mm to 1.5 mm. Regarding the rear end side in the long axis direction, the height T4 of the groove 45A is formed with a step difference of 0.5 mm to 1.5 mm.

Similarly, the boundary 32 between the neck portion 20 and the handle 30 on the back side intersects the curved contour 22 disposed on the front end side of the boundary 32 and the curved contour C21 disposed on the rear end side of the boundary 32 when viewed from the side The ridgeline of the part is formed. The position of the boundary 32 in the front direction, that is, the position where the curved contour C21 and the curved contour 22 cross is arranged on the back side of the position where the curved contour C21 and the curved contour C22 cross. Therefore, as compared with the rear end side of the first position P1 on the back side, a sharply curved surface is formed on the front end side of the first position P1.

Regarding the front end side in the long axis direction, the height T5 of the groove 45B is formed with a step difference of 0.5 mm to 1.5 mm. Regarding the rear end side in the long axis direction, the height T6 of the groove 45B is formed with a step difference of 0.5 mm to 1.5 mm.

FIG. 6 is a cross-sectional view of the shank 30 cut at the third position P3. As shown in FIG. 6, the cross-sectional shape of the shank 30 at the third position P3 is substantially circular. The maximum diameter of the handle 30 at the third position P3 is preferably 15 mm or more and 20 mm or less. When the maximum diameter of the handle 30 is lower than the lower limit value, when gripping the periphery of the third position P3 by palm grip, the grip area is small, and the middle finger and ring finger are insufficiently contacted and easy to slip. As a result, the grip may be reduced. When the maximum diameter of the handle 30 exceeds the upper limit value, when the periphery of the third position P3 is gripped in a grasping manner, the circumference becomes larger, making it difficult to grip.

FIG. 7 is an enlarged side view of the rear end of the handle 30 including the fourth position P4. As shown in FIG. 7, a through hole 46 penetrating in the front direction is formed near the rear end of the shank 30. In addition, as shown in FIGS. 1 and 7, a groove portion 47 extending from the through-hole 46 to the front end side is arranged on the front side of the shank portion 30. As an example, the groove portion 47 is formed in a semicircular cross-sectional shape and has a depth of about 1 mm.

Similarly, a groove portion 49 extending from the through-hole 46 to the front end side to the fourth position P4 is arranged on the back side of the shank portion 30. As an example, the groove 49 is formed in a semicircular cross-sectional shape and has a depth of about 1 mm.

The length of the handle body 2 is not particularly limited, and it is, for example, 100 mm to 200 mm. The handle body 2 is integrally formed into a long shape as a whole, for example, obtained by injection molding using resin as a material. Examples of the resin constituting the handle body 2 include resins having a bending modulus of elasticity (Japanese Industrial Standards (JIS) 7171) of 1000 MPa or more and 2200 MPa or less as an example, for example, polypropylene resin (Polypropylene, PP) ), Polyacetal resin (Polyoxymethylene (POM)), polystyrene resin (Polystyrene, PS), polyethylene terephthalate resin (Polyethylene terephthalate, PET), polybutylene terephthalate Resin (Polybutylene terephthalate (PBT), Acrylonitrile Butadiene Styrene (ABS), polyarylate resin, polycarbonate resin, Acrylonitrile Styrene (AS), etc. Among these, in consideration of cost, polypropylene resin which is a general-purpose resin is preferred.

The hair bundle is made by binding multiple toothbrush hairs. The length (hair length) from the planting surface 11 to the front end of the hair bundle can be determined in consideration of the hair hardness required for the hair bundle, and is set to, for example, 6 mm to 14 mm. The hair length of all hair bundles can be the same or different from each other.

The thickness of the hair bundle (hair bundle diameter) can be determined in consideration of the hair hardness required for the hair bundle, for example, set to 1 mm to 3 mm. The diameter of all hair bundles can be the same or different from each other.

Examples of toothbrush hairs constituting the hair bundle include toothbrush hairs (conical hairs) whose diameter gradually decreases toward the hair tip and the hair tips are sharpened, and toothbrush hairs (straight hair) whose diameters are approximately the same from the hair-planting surface 11 toward the hair tip Wait. Examples of straight hair include a person who sets the hair tip to be substantially parallel to the hair-planting surface 11 or a person who rounds the hair tip into a hemispherical shape.

Examples of wool materials include: polyamides such as 6-12 nylon (6-12NY), 6-10 nylon (6-10NY), polyethylene terephthalate (PET), and polybutylene terephthalate Ester (PBT), Polytrimethylene terephthalate (PTT), Polyethylene naphthalate (PEN), Polybutylene naphthalate (PBN) and other polyesters , Polyolefins such as polypropylene (PP), elastomer resins such as polyolefin elastomers, styrene elastomers, etc. These resin materials may be used alone or in combination of two or more. In addition, examples of toothbrush bristles include polyester toothbrush bristles having a multi-core structure having a core portion and at least one or more sheath portions provided outside the core portion.

The cross-sectional shape of the toothbrush bristles is not particularly limited, and it may be a circle such as a perfect circle or an ellipse, a polygon, a star, a three-leaf clover, or a four-leaf clover. The cross-sectional shapes of all toothbrush bristles can be the same or different.

The thickness of the toothbrush bristles can be determined by considering the material, etc. In the case of a circular cross section, for example, set to 6 mil (mil) ~ 9 mil (1 mil = 1/1000 inch (inch) = 0.025 mm) . In addition, it is also possible to arbitrarily use a plurality of toothbrush bristles with different thicknesses in consideration of usage feeling, brushing feeling, cleaning effect, durability, and the like.

The handle 2 in the toothbrush 1 of the above-described configuration is formed by injection molding using a mold having a space (cavity) having a shape and size corresponding to the handle 2, for example. The gate in which the molten resin is injected into the mold is disposed at the rear end portion of the handle body 2, for example. The handle body 2 is manufactured by filling the cavity of the mold with molten resin injected from the gate and taking it out of the mold after cooling.

In the handle body 2, there are cases where a gloss material such as pearl pigment is kneaded in a resin and blended for injection molding for the purpose of improving texture, design, or creation of high-grade sense. When the resin containing such a gloss material flows in the mold, the gloss material aligns. Therefore, the head 10 at the end of the flow, in particular, has jetting, Flow marks and weld lines tend to become obvious.

In the shank 2 of the present embodiment, the through-hole 46 is arranged at a position immediately adjacent to the gate 50. Therefore, the flow of molten resin injected from the gate 50 can be controlled by the shaft-shaped mold forming the through-hole 46. Thereby controlling the speed and the size of the flow path. Therefore, the appearance of spray marks and flow marks is unlikely to become apparent. Further, by arranging the groove portion 47 and the groove portion 49 extending from the through hole 46 to the front end side to the fourth position P4, the molten resin and the groove portion 47 and the groove portion resulting from the fusion of the through hole 46 are merged 49 overlap, so it is not easy to become obvious in appearance.

Next, the operation when grasping the handle 30 of the toothbrush 1 in a grasping manner will be described. (1st position P1) The front side of the 1st position P1 in the handle part 30 becomes a finger contact part of the neck 20 side, and the distal joint of a thumb is contact | abutted. The middle section of the index finger on the back side of the first position P1 abuts. Thereby, the handle 30 is held at the first position P1 so as to be sandwiched from the front side and the back side. At this time, since the groove portion 45A is arranged on the front side of the first position P1 and the groove portion 45B is arranged on the back side of the first position P1, the finger contact portion can be made tactilely clear. In addition, since the groove portion 45A and the groove portion 45B are circular and formed into a ring shape, including the width direction and the long axis direction, the movement in the plane substantially parallel to the tufting surface 11 also becomes even when the finger moves Not easy to slip.

In addition, since the cross-section of the first position P1 of the handle 30 is flat, the handle 30 abuts the thumb on the front side and the index finger on the back side with a wide area at the first position P1, and it is easy to apply force, which can be achieved Keep it stable. Therefore, the force applied to the handle 30 at the first position P1 close to the head 10 is easily transmitted to the head 10, whereby the operability is improved, and the tufted surface can sufficiently contact the teeth.

(Second position P2) The second position P2 functions as an auxiliary portion on the neck 20 side for distinguishing the first position P1 and the third position P3 when the handle 30 is held. When the handle 30 is held in a graspable manner, the distal joint of the thumb abuts on the front side of the second position P2, and the index finger abuts on the surrounding direction of the second position P2, whereby the auxiliary position can be held at the first position P1 The middle portion of the handle 30 is held so as to be sandwiched from the front side and the back side, and is held by the palm, middle finger, and ring finger at the third position P3. At the second position P2, the first tapered portion 43 is arranged when viewed from the front, so that the index finger can easily abut on the circumferential direction. In addition, since the first tapered portion 43 is arranged, the shape difference between the first position P1 and the third position P3 can be tactilely recognized when holding the handle 30, and can also be guided to be easily held naturally and comfortable (Fit).

(3rd position P3) The 3rd position P3 arrange | positions the 2nd largest bulging part 42 in the width direction, and functions as a grip stabilizing part. When gripping the handle 30 in a grasping manner, the palm, middle finger, and ring finger abut on the peripheral direction of the third position P3. The cross-sectional shape of the handle 30 at the third position P3 is substantially circular, and the maximum length PW3 and the maximum thickness PT3 in the width direction are the largest compared to the other positions P1, P2, and P4, and therefore, can be realized It is held comfortably and steadily in the holding hands.

(4th position P4) The area including the 4th position P4 up to the rear end functions as an auxiliary part when the grip 30 is gripped, especially when the 3rd position P3 is held by the palm, middle finger and ring finger . When grasping the handle 30 in a grasping manner, the ring finger of the ring finger, the little finger, and the palm of the palm abut on the direction around the fourth position P4. Since the maximum width PW4 and the thickness PT4 of the fourth position P4 are smaller than the maximum width PW3 and the thickness PT3 of the third position P3, the ring finger and the little finger that are shorter than the middle finger can also stably abut on the fourth position P4. Surrounding direction.

In the handle portion 30, the lengths in the width direction of the first position P1 to the fourth position P4 satisfy the relationship (1) and the relationship (2), respectively. The thumb and the index finger on the back side abut on the finger contact portion at the first position P1, and at the second bulge 42 at the third position P3 formed with the largest diameter, the palm, middle finger, and ring finger are brought into contact with the surrounding direction. This can be achieved comfortably and stably in the hand held. In addition, the minimum width PW2 of the first tapered portion 43 is smaller than the maximum width PW1 of the first bulging portion 41 and the maximum width PW3 of the second bulging portion 42, so it can be held at the first position P1 and the third position auxiliaryly P3 has the middle portion of the handle 30 held, and the operability during cleaning is improved by stable holding. Furthermore, since the minimum width PW4 of the rear end portion including the second tapered portion 44 is larger than the minimum width PW2 of the first tapered portion 43, it is possible to firmly assist the holding of the second bulging portion 42 from the rear end side. Helps to further stabilize the grip. The PW3 / PW2 is 1.3 or more and 1.5 or less, whereby the effect can be further obtained.

In addition, in the handle portion 30, the thicknesses of the first position P1 to the fourth position P4 satisfy the relationship (3) and the relationship (4), respectively, since the thickness of the first position P1 that becomes the finger contact portion is set to the most Since it is thin, the first position P1 can be easily and firmly held from the front side and the back side. Therefore, at a position close to the head 10, the force applied to the handle 30 is easily transmitted to the head 10, thereby, the operability is improved, and the tufted surface can fully contact the teeth. In addition, since the thickness of the first position P1 is thin, a sharply curved surface is formed between the boundary 31 and the boundary 32 of the neck 20 and the handle 30 and the first position P1. Therefore, the thumb and index finger that are in contact with the finger contact portion are engaged with the curved surface at the rear end side, thereby suppressing the shaking of the grip 30 held in the long axis direction. The PT3 / PT1 is 1.7 or more and 2.5 or less, whereby the effect can be further obtained.

In addition, in the shank portion 30, the curved contour C1 of the first bulged portion 41, the curved contour C2 of the first tapered portion 43, the curved contour C3 of the second bulged portion 42, and the curved contour C4 of the second tapered portion 44 In the long axis direction, it is circumscribed with the adjacent curve contour. The front side curve contour C11, curve contour C12, curve contour C13, curve contour C14, and curve contour C15 are circumscribed in the long axis direction with the adjacent curve contour, the back side The curved contour C21, the curved contour C22, the curved contour C23, the curved contour C24 and the curved contour C25 are circumscribed with the adjacent curved contour in the long axis direction, whereby the contours are smoothly connected. Therefore, the handle 30 can also handle various holding methods, and the toothbrush 1 having excellent operability and versatility can be realized.

In this way, in the toothbrush 1 of the present embodiment, by appropriately setting the shape and size of the handle 30, it is possible to obtain the toothbrush 1 having high grip for the handle 30 and high operability during cleaning without using soft Department and so on and cause cost increase. In particular, in this embodiment, the structure of the head 10 having a wide-width wide-head specification causes large interference of hair bundles when the bristle portion abuts on the cleaning portion, thereby shaking the grip portion, and Even if it is difficult to reach the cleaning site properly, the handle 30 is comfortable in the hand and has a high grip, so the operability is good and the bristle portion can fully contact the teeth.

In the above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings, and the present invention is of course not limited to the examples. The various shapes and combinations of the constituent members shown in the above examples are examples, and various changes can be made based on design requirements and the like without departing from the gist of the present invention.

For example, in the above embodiment, the configuration in which the groove portion 45A and the groove portion 45B are provided on both the front and back sides of the first position P1 is exemplified. However, the configuration may be provided only on the front or back side.

In addition, in the above-mentioned embodiment, the configuration using the head 10 of the wide-head specification is exemplified, but it is not limited to the wide-head specification. Even if it is a head of a general type or a small specification, the present invention can be applied. [Industry availability]

The invention can be applied to toothbrushes.

1‧‧‧toothbrush

2‧‧‧handle

10‧‧‧Head

11‧‧‧Flocked surface

12‧‧‧Planting pores

20‧‧‧ Neck

21‧‧‧curve contour

22‧‧‧curve contour

30‧‧‧handle

31, 32‧‧‧ border

41‧‧‧The first bulge

42‧‧‧The second bulge

43‧‧‧First thinning part

44‧‧‧Second thinning part

45A, 45B‧‧‧Slot

46‧‧‧Through hole

47, 49‧‧‧Slot

50‧‧‧Gate

C1 ～ C4, C11 ～ C15, C21 ～ C25, C31, C32‧curve outline

P1‧‧‧1st position

P2‧‧‧ 2nd position

P3‧‧‧3rd position

P4‧‧‧ 4th position

T1, T2‧‧‧ Height

T3, T4‧‧‧‧45A height

T5, T6‧‧‧‧45B height

W1‧‧‧Maximum width of head

FIG. 1 is a diagram showing an embodiment of the present invention, and is a front view of a toothbrush 1. FIG. 2 is a side view of the toothbrush 1. FIG. 3 is a back view of the toothbrush 1. 4 is a cross-sectional view of the shank 30 cut at the first position P1. FIG. 5 is an enlarged side view of the first position P1 in FIG. 2. FIG. 6 is a cross-sectional view of the shank 30 cut at the third position P3. FIG. 7 is an enlarged side view of the rear end of the handle 30 including the fourth position P4.

Claims (6)

A toothbrush, characterized by comprising: a head portion, which is arranged on the front end side in the long axis direction and is provided with hair bundles on the hair-planting surface; a neck portion, which is extended to the rear end side of the head portion; and a handle portion, which extends It is provided on the rear end side of the neck, and the handle portion has a first bulging portion, which is disposed on the rear end side of the neck, and is viewed from the front in a direction orthogonal to the hair-planting surface. When, in the width direction orthogonal to the long axis direction and the front direction, the two sides are continuously changed symmetrically and swelled; the first tapered portion is disposed at the rear end of the first swelled portion Side, symmetrically continuously changing and narrowing on both sides in the width direction; a second bulging portion, disposed on the rear end side of the first narrowing portion, symmetrical on both sides in the width direction Continually changing to swell; and a second tapered portion, which is arranged on the rear end side of the second bulging portion, continuously changes symmetrically on both sides in the width direction and narrows, the first The swelled portion is at a first position between the neck and the first tapered portion in the long axis direction, the width The length in the direction becomes maximum, the first tapered portion is at a second position between the first bulging portion and the second bulging portion in the long axis direction, and the length in the width direction becomes Minimum, the second bulged portion is at a third position between the first tapered portion and the second tapered portion in the long axis direction, the length in the width direction becomes the largest, the The second tapered portion is at a fourth position on the rear end side of the second bulging portion in the long axis direction, the length in the width direction becomes the smallest, and if the second 1 The widthwise length of the tapered portion is PW2, and the widthwise length of the second bulging portion at the third position is PW3, then the PW3 is 15 mm or more and 20 mm or less, PW3 / PW2 is 1.3 or more and 1.5 or less, if the thickness in the front direction at the first position is PT1, and the thickness in the front direction at the third position is PT3, Then, the PT3 is 15 mm or more and 20 mm or less, and the PT3 / PT1 is 1.7 or more and 2.5 or less. The toothbrush according to item 1 of the patent application scope, wherein the first bulging portion, the first tapering portion, the second bulging portion, and the second tapering portion are determined by the respective front views The contour line is formed by a curve that circumscribes the adjacent bulge or tapered portion in the long axis direction. The toothbrush according to claim 1 or claim 2, wherein the cross-sectional shape of the handle at the first position is a flat shape with a length in the width direction greater than a thickness in the front direction, And the cross-sectional shape of the shank at the third position is substantially circular. The toothbrush according to any one of claims 1 to 3, wherein at least one of the front side and the back side of the handle at the first position has a groove. The toothbrush according to item 4 of the patent application, wherein the groove portion is formed in a ring shape. The toothbrush according to any one of claims 1 to 5, wherein the maximum length of the head in the width direction is 13 mm or more.