toothbrush

Abstract

To provide a toothbrush that allows for smooth brushing without causing any discomfort. [Solution] The device has a gripping portion and a connecting body connected to the gripping portion on one side in the depth direction, the connecting body having a first brush body located on one side in the depth direction of the gripping portion and a second brush body located between the gripping portion and the first brush body in the depth direction and positioned away from the first brush body, the first brush body having a first support formed in a U shape along the circumferential direction centered on an axis extending in the meshing direction and a first brush portion extending from the first support to the other side in the depth direction, the second brush body having a second support formed in a U shape along the circumferential direction and a second brush portion extending from the second support to one side in the depth direction, at least one of the first support and the second support has a recess in the meshing direction extending from at least one of the end on one side and the other end in the meshing direction, the recess is positioned at a location including the center in the circumferential direction.

Description

Technical Field

[0001] The present invention relates to a toothbrush.

Background Art

[0002] As a toothbrush for cleaning the entire dentition at once, Patent Document 1 discloses a mouthpiece-type electrically driven toothbrush. The electric toothbrush disclosed in Patent Document 1 includes a mouthpiece disposed on a support so that a cleaning element, which is a brush part, engages substantially all teeth at least on one of the user's upper and lower jaws simultaneously, and an electric drive unit that is detachably fixed to the mouthpiece and has at least one vibration element for performing a vibration motion and serves as a gripping part.

[0003] The mouthpiece-type toothbrush has a brush part provided on a U-shaped support disposed on the inner side located on the lingual side and the outer side located on the buccal side, and the teeth can be brushed by moving the mouthpiece part left and right while holding it.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The support is made such that the height in the meshing direction is constant or gradually transitions from the front tooth side to the back tooth side. This is to make the upper and lower ends of the mouthpiece in the height direction contact the gingiva, buccal mucosa, or retromolar triangle of the oral tissue when biting, so as to stabilize the mouthpiece in the oral cavity as much as possible. However, when wearing the mouthpiece, problems can arise such as a feeling of pressure or difficulty moving it when brushing from side to side. In addition, the inner or outer support may come into contact with, for example, the palate or upper lip frenulum in the case of the upper jaw, or the floor of the mouth or lower lip frenulum in the case of the lower jaw. In this case, for example, since the palate, floor of the mouth, upper lip frenulum, and lower lip frenulum are all soft tissues, contact with the support can cause discomfort. Contact with the support can also make it difficult to move the mouthpiece.

[0006] This invention has been made with the above points in mind, and aims to provide a toothbrush that allows for smooth brushing without causing any discomfort. [Means for solving the problem]

[0007] The present invention has the following aspects. [1] The gripping part, A connecting body is connected to one side of the gripping portion in the depth direction perpendicular to the meshing direction, It has, The aforementioned connecting body, A first brush body located on one side in the depth direction of the gripping portion, A second brush body is positioned between the gripping portion and the first brush body in the depth direction, and is positioned away from the first brush body, It has, The first brush body is A first support is formed in a U-shape along the circumferential direction centered on the axis extending in the meshing direction, A first brush portion extending from the first support to the other side in the depth direction, It has, The second brush body is A second support formed in a U-shape along the circumferential direction, A second brush portion extending from the second support to one side in the depth direction, It has, A toothbrush in which at least one of the first support and the second support has a recess in the direction of occlusion extending from at least one of the ends on one side and the other side in the direction of occlusion. [2] The aforementioned recess is provided at least at the maxillary end in the occlusal direction, The toothbrush described in [1] above. [3] The recess is positioned at a location including the center in the circumferential direction, If the total length in the circumferential direction on one side in the depth direction of the first support is taken as 100%, The maximum length of the recess in the circumferential direction is 10% or more and 40% or less. The toothbrush described in [1] or [2] above. [4] At least one of the first support and the second support has a tapered shape in which the dimension in the meshing direction gradually decreases from the center in the circumferential direction towards the end. A toothbrush as described in any one of the above items [1] to [3]. [5] At least one of the first support and the second support is provided with a hard portion that is harder than at least one of the first support and the second support, at least in the area where the recess is provided in the circumferential direction. A toothbrush as described in any one of the above items [1] to [4]. [6] The gripping portion has a shaft portion extending to one side in the depth direction, The second support has a bearing portion on which the shaft portion is mounted, The shaft portion is positioned further to the other side in the depth direction than the second support. A toothbrush as described in any one of the above items [1] to [5]. [7] The region where the second support and the bearing portion are connected is The dimension in the meshing direction is longer than the maximum dimension of the recess in the meshing direction. The end on one side in the circumferential direction is located further to the other side in the circumferential direction than the end on the other side in the circumferential direction in the recess, The end on the other side in the circumferential direction is located further on the other side in the circumferential direction than the end on the other side in the circumferential direction in the recess. The toothbrush according to [6] above. [8] Having an index portion that serves as an index regarding the position in the meshing direction of the first brush body and the second brush body. The toothbrush according to any one of [1] to [7] above.

Advantages of the Invention

[0008] In the present invention, it is possible to provide a toothbrush that can smoothly perform a brushing operation without feeling discomfort.

Brief Description of the Drawings

[0009] [Figure 1] It is a front view of the toothbrush 1 of the present invention. [Figure 2] It is an external perspective view of the mouthpiece portion 20 of the first embodiment. [Figure 3] It is a view of the mouthpiece portion 20 seen from the inside in the depth direction. [Figure 4] It is a cross-sectional view taken along the line B - B in FIG. 2. [Figure 5] It is a front view of the first brush body 30, the second brush body 60, and the third brush body 80 excluding the connection portions to the first brush portion 41, the second brush portion 71, and the grip portion 10. [Figure 6] It is a right side view of FIG. 1. [Figure 7] It is a view of the mouthpiece portion 20 seen from the outside in the depth direction. [Figure 8] It is a view of the mouthpiece portion 20 of the second embodiment seen from the inside in the depth direction. [Figure 9] It is a perspective view of the mouthpiece portion 20 of the second embodiment seen from the inside in the depth direction. [Figure 10] It is a right side view showing a modified example of the mouthpiece portion 20. <000^112>

Modes for Carrying Out the Invention

[0010] Hereinafter, embodiments of the toothbrush of the present invention will be described with reference to Figures 1 to 9. The following embodiments represent one aspect of the present invention and are not intended to limit it. They can be modified at will within the scope of the technical idea of ​​the present invention. Furthermore, in the following drawings, the scale and number of components in each structure differ from the actual structure in order to make the components easier to understand.

[0011] In the coordinate systems shown in each figure, the Z-axis direction is the occlusal direction and is the vertical direction parallel to the direction in which axis J extends. The θ-direction is the circumferential direction centered on axis J and is the direction along the dentition. In this embodiment, the circumferential direction includes not only the direction along the arc centered on axis J, but also the direction along the tangent to the arc. The Y-axis direction is the direction perpendicular to the θ-direction and the Z-axis direction and is the depth direction within the oral cavity. In the following explanation, the direction parallel to the Z-axis direction will be called the "occlusal direction". The maxillary side, which is the positive side in the Z-axis direction, will be called the "upper side", and the mandibular side, which is the negative side in the Z-axis direction, will be called the "lower side". The positive side in the θ-direction will be called the "left side", and the negative side in the θ-direction will be called the "right side". The lingual side, which is the positive side in the depth direction, will be called the "inner side", and the buccal side, which is the negative side in the depth direction, will be called the "outer side". The "inner side" corresponds to "one side in the depth direction". The "outer side" corresponds to "the other side in the depth direction". The "upper side" corresponds to "one side in the direction of occlusion." The "lower side" corresponds to "the other side in the direction of occlusion."

[0012] Figure 1 is a front view of toothbrush 1. As shown in Figure 1, the toothbrush 1 is a mouthpiece-type toothbrush and has a gripping part 10 and a connecting part 20. Hereinafter, the connecting part 20 will be referred to as the mouthpiece part 20. The mouthpiece portion 20 is subjected to vibration via the gripping portion 10. A shaft (axis portion) 14 protrudes from the gripping portion 10 and is connected to a fitting recess 23 of the bearing portion 22 of the mouthpiece portion 20, which will be described later. In other words, the shaft 14 is the vibration axis.

[0013] The present invention is applicable to any of the following configurations: one in which a brushing motion is manually applied from the gripping part 10 to the mouthpiece part 20 in the up-and-down, left-and-right, front-and-back, and combinations thereof; one in which vibration is manually applied; and one in which vibration is electrically applied from the gripping part 10 to the mouthpiece part 20. In the configuration in which vibration is manually applied, the shaft 14 serves as a mounting shaft for detachably (replaceably) connecting the mouthpiece part 20 to the gripping part 10. In this embodiment, an electric drive unit is provided on the gripping portion 10, and a configuration is described in which vibrations generated by the operation of the electric drive unit are applied to the mouthpiece portion 20.

[0014] The electric drive unit comprises a power supply unit 11, a vibration element 12, and a control unit 13. The control unit 13 drives the vibration element 12 using power from the power supply unit 11. The power supply unit 11 is composed of, for example, a rechargeable battery or a battery. The vibration element 12 is composed of, for example, a piezoelectric element, an electromagnetic acoustic transducer, an unbalanced motor, etc. The vibration generated by the vibration element 12 is a vibration that rotates around an axis extending in the depth direction, and repeatedly reverses the direction of rotation at a constant predetermined rotation angle. In the gripping section 10, the shaft 14 connected to the electric drive unit vibrates by repeatedly reversing its direction of rotation. As the shaft 14 vibrates due to the drive of the vibrating element 12, the mouthpiece section 20 vibrates by repeatedly reversing its direction of rotation.

[0015] [First embodiment of the mouthpiece portion 20] The mouthpiece section 20 includes a first brush body 30, a second brush body 60, a third brush body 80, a bearing section 22, an indicator section 24, and a hard section 25.

[0016] The first brush body 30 is located inward in the depth direction from the gripping portion 10. The second brush body 60 is located between the gripping portion 10 and the first brush body 30 in the depth direction, and is positioned away from the first brush body 30. The second brush body 60 is connected to the gripping portion 10 via the bearing portion 22.

[0017] When the mouthpiece portion 20 is placed in the oral cavity, the first brush body 30 is positioned on the lingual side, which is inside the dental arch. When the mouthpiece portion 20 is placed in the oral cavity, the second brush body 60 is positioned on the buccal side, which is outside the dental arch.

[0018] The first brush body 30 includes a first support 31 and a first brush portion 41. The first support 31 supports the base end of the first brush portion 41. When viewed from above, the first support 31 is formed in a U-shape (horseshoe shape) along the circumferential direction centered on the axis J. The first support 31 is U-shaped with an opening on the inside in the depth direction.

[0019] The second brush body 60 includes a second support 61 and a second brush portion 71. The second support 61 supports the base end of the second brush portion 71. When viewed from above, the second support 61 is formed in a U-shape (horseshoe shape) along the circumferential direction centered on the axis J. The second support 61 is U-shaped with an opening on the inside.

[0020] The range in which the first brush body 30 and the second brush body 60 face the dentition is not limited to the entire dentition, but may be configured so that only a portion of the anterior teeth (central incisors, lateral incisors), canines, and posterior teeth (first premolars, second premolars, first molars, second molars) face each other.

[0021] The third brush body 80 is positioned between the first brush body 30 and the second brush body 60 in the depth direction. The third brush body 80 has a connecting portion 81 and a third brush portion 91. The connecting portion 81 is positioned between the first brush body 30 and the second brush body 60 in the depth direction and is formed in a U-shape along the circumferential direction. The connecting portion 81 is plate-shaped and perpendicular to the meshing direction. The connecting portion 81 connects the first support 31 and the second support 61 in the depth direction.

[0022] Figure 2 is an external perspective view of the mouthpiece portion 20 as seen from the inside in the depth direction. As shown in Figure 2, the third brush portion 91 extends from the connecting portion 81 to both sides in the occlusal direction. The third brush portion 91 has a mountain-shaped bristle length profile with a peak at the midpoint in the depth direction. The mountain-shaped bristle length profile of the third brush portion 91 provides a profile that fits the occlusal surfaces of the teeth, improving cleaning power. The third brush portion 91 is preferably positioned, for example, opposite the molars. Because the third brush portion 91 is positioned opposite the molars and protrudes upward and downward, it can effectively clean the occlusal surfaces of the molars, which are difficult to reach with the first brush portion 41 and the second brush portion 71.

[0023] Figure 3 is a rear view of the mouthpiece section 20, seen from the inside in the depth direction. Figure 4 is a cross-sectional view of BB in Figure 2. In Figure 3, the mouthpiece section 20 is shown excluding the first brush section 41, the second brush section 71, and the third brush section 91. In subsequent drawings, the first brush section 41, the second brush section 71, and the third brush section 91 may also be omitted as appropriate.

[0024] As shown in Figures 1 to 4, at least one of the first support 31 and the second support 61 has a recess 32. The recess 32 is recessed in the meshing direction from at least one of the upper end and the lower end in the meshing direction. The recess 32 is located in a position that includes the center in the circumferential direction. In this embodiment, the first support 31 has a recess 32 that is recessed downward from the upper end in the meshing direction. The recess 32 is formed with an equal distance length from the center in the circumferential direction to both sides in the circumferential direction.

[0025] In the inner first support 31 in the depth direction, a recess 32 is provided that extends downward from the upper end in the occlusal direction. This reduces the area that comes into contact with the maxillary gingiva or buccal mucosa, thereby alleviating the feeling of pressure when the mouthpiece 20 is held in the mouth. When brushing by moving from side to side, the feeling of friction is also reduced, allowing for smoother brushing. Furthermore, in this embodiment, since the recess 32 is positioned to include the center in the circumferential direction, contact with the upper palate can be suppressed. By suppressing contact with the upper palate, it becomes possible to brush smoothly without feeling any discomfort when holding the mouthpiece portion 20 in the mouth and when moving it from side to side for brushing.

[0026] In particular, the palate on the maxillary side is shallower than the floor of the mouth on the mandibular side and is more likely to come into contact with the first support 31. Therefore, by providing a recess 32 on the maxillary side of the first support 31, it becomes easier to achieve a smoother brushing effect without feeling any discomfort.

[0027] Figure 5 is a front view of the first brush body 30, the second brush body 60, and the third brush body 80, excluding the connection points with the first brush section 41, the second brush section 71, the third brush section 91, and the gripping section 10. In Figure 5, the area outside the first support body 31 in the depth direction is partially shown as a cross-section at the center position in the depth direction.

[0028] As shown in Figure 5, if the total length L1 in the circumferential direction on the inside in the depth direction of the first support 31 is taken as 100%, then, as shown in Figure 3, the maximum circumferential length L32 of the recess 32 is preferably 10% or more and 40% or less. If the circumferential end of the recess 32 is formed as a slope, the maximum circumferential length L32 of the recess 32 is defined as the circumferential length between the upper ends.

[0029] If the maximum length L32 is less than 10%, the relief of pressure is less noticeable, and the recess 32 cannot cover an area equivalent to one or two teeth in the circumferential direction, so the first support 31 may come into contact with the palate of the maxilla. In the circumferential area where the recess 32 is provided, the number of first brush parts 41 decreases, so if the maximum length L32 exceeds 40%, the cleaning power (brushing force) on the inner surface of the maxillary teeth may decrease. In addition, the stability when the mouthpiece part 20 is held in the mouth or moved from side to side is impaired. By setting the maximum length L32 to 10% or more and 40% or less, it is possible to maintain high cleaning power while maintaining the effect of smooth brushing without feeling discomfort.

[0030] The maximum length L32 is preferably 12 mm or more and 22 mm or less. If the maximum length L32 is less than 12 mm, the relief of pressure will be difficult to feel, and the recess 32 will not be able to cover an area equivalent to one or two teeth in the circumferential direction, so the first support 31 may come into contact with the palate of the maxilla. If the maximum length L32 exceeds 22 mm, the number of first brush parts 41 will be reduced in the circumferential area where the recess 32 is provided, so the cleaning power (brushing force) on the inner surface of the maxillary teeth may decrease. In addition, the stability when the mouthpiece part 20 is held in the mouth or moved from side to side will be impaired. By setting the maximum length L32 to 12 mm or more and 22 mm or less, it is possible to maintain high cleaning power while maintaining the effect of smooth brushing without feeling discomfort.

[0031] When the circumferential end of the depression 32 is formed as a slope, as shown in Figure 3, the intersection angle θ1 between the bottom of the depression 32 and the slope is preferably 90° or more and 160° or less, and more preferably 100° or more and 150° or less. If the intersection angle θ1 is less than 90°, the upper end of the recess 32 tends to close slightly, making it difficult to avoid contact with the palate (palatal tissue). Also, because it becomes claw-shaped, if contact does occur, the resistance with the palate (palatal tissue) increases, resulting in greater discomfort. On the other hand, if the intersection angle θ1 exceeds 160°, the circumferential length of the upper end forming the recess 32 becomes excessively long, and the area with less resin expands circumferentially, impairing stability during brushing. By having the intersection angle θ1 between the bottom of the recess 32 and the slope within the above range, the first support 31 becomes less likely to come into contact with the palate (palatal tissue), or even if it does come into contact, the resistance with the palate (palatal tissue) is reduced to the absolute minimum, allowing for smooth brushing without causing any discomfort.

[0032] As shown in Figure 3, L33 is the distance between the uppermost position at the circumferential center of the first support 31 (as assumed when the recess 32 is not provided) and the center of the first support 31 in the meshing direction. L34 is the distance (depth) between the uppermost position of the slope forming the recess 32 and the bottom of the recess 32. When the distance L33 is set to 100%, it is preferable that the distance L34 is between 10% and 40%.

[0033] If the distance L34 is less than 10% of the distance L33, the recess 32 becomes shallower, and the first support 31 may come into contact with the palate or floor of the mouth during brushing, potentially causing discomfort. Furthermore, contact with the support may make it difficult to move the mouthpiece 20. If the distance L34 exceeds 40% of the distance L33, the number of first brush parts 41, described later, decreases, which may reduce the cleaning power (brushing power). By setting the distance L34 to between 10% and 40% of the distance L33, it is possible to maintain high cleaning power while ensuring smooth brushing without causing any discomfort.

[0034] The distance L34 is preferably between 1.5 mm and 5.0 mm. If the distance L34 is less than 1.5 mm, the recess 32 becomes shallower, and the first support 31 may come into contact with the palate during brushing, potentially causing discomfort. Furthermore, the contact between the palate and the first support 31 may make it difficult to move the mouthpiece 20. If the distance L34 exceeds 5.0 mm, the number of first brush 41 bristles decreases, which may reduce the cleaning power (brushing force). By setting the distance L34 to between 1.5mm and 5.0mm, it is possible to maintain high cleaning power while ensuring smooth brushing without causing any discomfort.

[0035] Figure 6 is a right side view of Figure 1. As shown in Figures 2, 3, and 6, at least one of the first support 31 and the second support 61 has a tapered shape in which the dimension in the meshing direction is largest at the center in the circumferential direction, and the dimension in the meshing direction gradually decreases from the center in the circumferential direction towards the end. In this embodiment, the second support 61 has a tapered shape in which the dimension in the meshing direction gradually decreases from the center in the circumferential direction towards the end.

[0036] In other words, the second support 61 has its upper end in the occlusal direction located at the uppermost position in the circumferential center, and extends in a direction that gradually moves downward towards the circumferential end. The second support 61 has its lower end in the occlusal direction located at the lowermost position in the circumferential center, and extends in a direction that gradually moves upward towards the circumferential end.

[0037] The first support 31 has its lower end in the occlusal direction located at the lowest point in the circumferential center, and extends gradually upward towards the circumferential end. On the other hand, the first support 31 has the largest occlusal dimension at both ends of the recess 32 in the circumferential direction, and the occlusal dimension gradually decreases towards the end. In other words, the first support 31 has less resin in the central circumferential region where the recess 32 is located compared to the surrounding region. Therefore, the first support 31 is prone to bending in the central circumferential region, which carries the risk of reduced cleaning sensation in the front teeth or causing discomfort due to differences in cleaning sensation and vibration intensity between the front and back teeth.

[0038] In this embodiment, the occlusal dimension is largest at both circumferential ends of the recess 32. As a result, the anterior tooth side, where the recess 32 is provided and the amount of resin is small, has a larger occlusal dimension, while the posterior tooth side, where the recess 32 is not provided, has a smaller occlusal dimension. This balances the amount of resin between the anterior and posterior tooth sides, ensuring a balance in the degree of deflection and vibration strength, while providing the effect of smooth brushing without causing discomfort.

[0039] As shown in Figure 4, the first brush portion 41 is provided on the first support 31 with vertical spacing between them. The first brush portion 41 is provided on the upper end and lower end of the first support 31, respectively. The first brush portion 41 extends inclined away from the connecting portion 81 in the meshing direction as it moves outward in the depth direction from the outer brush surface 31a in the depth direction of the first support 31. In the region where the recess 32 is provided in the circumferential direction, the inclination angle θ2 of the first brush portion 41 with respect to the depth direction is preferably 30° or more and 70° or less.

[0040] Since the first brush portion 41 is not provided in the recess 32, there is a risk of missed spots, especially at the gum line, among the teeth facing the recess 32 on the outside in the depth direction. By tilting the first brush portion 41, located on the lower side of the recess 32, upward at an inclination angle θ2, the tip of the first brush portion 41 is positioned on the outside in the depth direction of the recess 32. Therefore, it becomes possible to brush the teeth facing the recess 32 on the outside in the depth direction as well.

[0041] If the inclination angle θ2 is less than 30°, the length of time that the tip of the first brush portion 41 is located outside the depth direction of the recess 32 becomes shorter, which may result in insufficient brushing of the opposing teeth outside the depth direction of the recess 32. If the inclination angle θ2 exceeds 70°, the first brush portion 41 may be pressed too hard against the gums. By setting the inclination angle θ2 to 30° or more and 70° or less, sufficient brushing of the opposing teeth outside the depth direction of the recess 32 can be achieved without excessive pressure on the gums.

[0042] The second brush portion 71 is provided on the second support 61 with vertical spacing between them. The second brush portion 71 is provided on the upper end and lower end of the second support 61, respectively. The second brush portion 71 extends inclined away from the connecting portion 81 in the meshing direction as it moves inward in the depth direction from the inner brush surface 61a in the depth direction of the second support 61. The inclination angle of the second brush portion 71 can be, for example, the same as that of the first brush portion 41.

[0043] The first support 31 and the first brush portion 41 are made of the same resin material. The second support 61 and the second brush portion 71 are made of the same resin material. The hardness of the first brush portion 41 and the second brush portion 71 is preferably made of a soft resin with a Shore A hardness of 60 or higher, and more preferably made of a soft resin with a Shore D hardness of 70 or lower. "Shore A hardness" refers to the Durometer A hardness of plastics measured according to JIS K 7215 or JIS K 6253. "Shore D hardness" refers to the hardness of Durometer Type D as defined in JIS K 6253.

[0044] One could consider using a soft resin with a Shore A hardness of less than 60 for the first brush portion 41 and the second brush portion 71, thereby giving flexibility to the first brush body 30 and the second brush body 60, and allowing the mouthpiece portion 20 to flex to reduce discomfort during brushing. However, this would result in a decrease in cleaning function. Furthermore, since contact with the palate and other parts is unavoidable, it would become difficult to move the mouthpiece portion 20. On the other hand, by setting the hardness of the first brush portion 41 and the second brush portion 71 to Shore A hardness 60 or higher, sufficient cleaning function can be ensured. In addition, the recess 32 prevents contact with the palate, etc., thereby reducing discomfort during brushing and making it easier to move the mouthpiece portion 20. Furthermore, by setting the hardness of the first brush portion 41 and the second brush portion 71 to Shore D hardness 70 or lower, flexibility of the mouthpiece portion 20 can be ensured, making it easier to move in the oral cavity and also facilitating removal from the mold after molding.

[0045] The bearing portion 22 is located on the outer side of the second support 61 in the depth direction. The bearing portion 22 protrudes from the center of the second support 61 in the circumferential direction outward in the depth direction. As shown in Figure 6, the region where the second support 61 and the bearing portion 22 are connected has a maximum dimension H22 in the meshing direction that is longer than the distance L34 (see Figure 3), which is the maximum dimension of the recess 32 in the meshing direction.

[0046] Furthermore, as shown in Figure 5, the region where the second support 61 and the bearing portion 22 are connected has a circumferential left end 22A located further to the left than the circumferential left end 32A in the recess 32. Also, the region where the second support 61 and the bearing portion 22 are connected has a circumferential right end 22B located further to the right than the circumferential right end 32B in the recess 32.

[0047] For example, if the meshing direction is excessively engaged, the bottom of the recess 32 may come into contact with the palate or other body parts. However, if the maximum dimension H22 in the meshing direction of the area where the second support 61 and the bearing portion 22 are connected is longer than the distance L34, which is the maximum dimension of the recess 32 in the meshing direction, then when the meshing is excessive, the lips will touch the bearing portion 22 before the bottom of the recess 32 comes into contact with the palate or other body parts. Therefore, by alerting the user, excessive meshing can be suppressed, and contact between the first support 31 and the palate or other body parts can be prevented.

[0048] Furthermore, if the brushing stroke is too long, the recess 32 may deviate from the palate, etc., potentially causing the first support 31 to come into contact with the palate, etc. In contrast, the circumferential left end 22A of the bearing portion 22, which connects to the second support 61, is located further to the left than the circumferential left end 32A of the recess 32, and the circumferential right end 22B of the bearing portion 22, which connects to the second support 61, is located further to the right than the circumferential right end 32B of the recess 32. Therefore, if the brushing stroke is too long, the bearing portion 22 will touch the corner of the mouth before the recess 32 deviates from the palate, etc. Thus, by alerting the user, the stroke length can be adjusted appropriately, preventing the first support 31 from coming into contact with the palate, etc.

[0049] The maximum dimension H22 of the bearing portion 22 is preferably 5 mm or more and 13 mm or less. If the maximum dimension H22 is less than 5 mm, if the lips touch the bearing portion 22 when the grip is excessive, the bottom of the recess 32 may touch the palate or the like before the user is alerted. If the maximum dimension H22 exceeds 13 mm, even with proper gripping, the lips may touch the bearing portion 22, potentially hindering the gripping process. By setting the maximum dimension H22 to 5mm or more and 13mm or less, it is possible to alert the user when the recess 32 deviates from the palate, etc., without hindering proper biting.

[0050] The maximum distance between end 22A and end 22B of the bearing portion 22 is preferably 12 mm or more and 25 mm or less. If the maximum distance between end 22A and end 22B is less than 12 mm, the recess 32 may disengage from the palate, etc., before the bearing portion 22 touches the corner of the mouth when the brushing stroke is too long. If the maximum distance between end 22A and end 22B exceeds 25 mm, the corner of the mouth may touch the bearing portion 22 even with an appropriate brushing stroke, which may hinder brushing. By setting the maximum distance between end 22A and end 32B to 12mm or more and 25mm or less, it is possible to alert the user if the brushing stroke is too long without hindering proper brushing.

[0051] As shown in Figure 5, the length dimension L22 in the depth direction of the bearing portion 22 is preferably 10 mm or more and 25 mm or less. If the length dimension L22 is less than 10 mm, the area of ​​the bearing portion 22 that comes into contact with the lips or corners of the mouth may become too small, potentially failing to adequately alert the user. If the length dimension L22 exceeds 25 mm, the center of gravity may become too heavily skewed towards the gripping portion 10, potentially placing too much strain on the user. By setting the depth dimension L22 to between 10mm and 25mm, it is possible to ensure a sufficient contact area to alert the user while preventing the center of gravity from shifting too far towards the handle.

[0052] The indicator section 24 is an indicator of the position of the first brush body 30 and the second brush body 60 in the meshing direction. In this embodiment, the indicator section 24 is located on the upper surface of the bearing section 22, as shown in Figures 1 and 6. The indicator section 24 is formed with an "upper" mark indicating that the upper surface of the bearing section 22 is positioned on the upper side during use. In addition to the above mark, other indicators indicating that the upper surface of the bearing section 22 is positioned on the upper side during use may include symbols such as arrows, shapes such as recesses or protrusions, or images indicating the upper side. The indicator section 24 may also be located on the side of the first support 31 facing inward in the depth direction, on the side of the second support 61 facing outward in the depth direction, or on the upper surface of the connecting section 81. Furthermore, the indicator section 24 may also be an indicator indicating that the lower surface of the bearing section 22 is positioned on the lower side during use, or an indicator that shows both the upper and lower sides.

[0053] The presence of the indicator portion 24 allows the user to hold the mouthpiece portion 20 in the correct position in the occlusal direction and brush their teeth, even when the first brush body 30 and the second brush body 60 are configured asymmetrically in the occlusal direction. For example, as shown in Figure 3, in the case of an asymmetrical shape with a recess 32 only on the inner side of the maxilla, contact with the soft tissue of the palate (palatal tissue) can be suppressed. However, if the mouthpiece is worn upside down, the soft tissue of the palate (palatal tissue) will come into contact with the first support 31, which does not have a recess 32. By providing the indicator portion 24, the user can avoid wearing (wearing) the mouthpiece upside down, thereby enhancing the effect of the present invention.

[0054] At least one of the first support 31 and the second support 61 is provided with a hardened portion 25 that is harder than at least one of the first support 31 and the second support 61. Figure 7 is a view of the mouthpiece portion 20 from the outside in the depth direction. As shown in Figures 1, 4, 5 and 7, the hardened portion 25 of this embodiment is arranged across the second support 61 and the bearing portion 22. The hardened portion 25 has a first portion 25A and a second portion 25B. The first portion 25A and the second portion 25B may be configured to be separate and not connected.

[0055] The first part 25A is located inside the bearing portion 22. The outer circumference of the first part 25A is covered by the bearing portion 22. As shown in Figure 7, the first part 25A has an oval shape extending in the circumferential direction. The first part 25A has a fitting recess 23. The fitting recess 23 is located in the center in the circumferential direction and opens outward in the depth direction from a position outside the second support 61 in the depth direction. As shown in Figures 4 and 7, the fitting recess 23 has a circular portion 23a located outside the circular portion 23a in the depth direction and having a circular cross-section, and a semicircular portion 23b located inside the circular portion 23a in the depth direction and having a substantially semicircular (D-shaped) cross-section. The inner end of the semicircular portion 23b in the depth direction is located outside the second support 61 in the depth direction.

[0056] The shaft 14 is inserted into the fitting recess 23 from the outside in the depth direction and fitted into it. The shaft 14 has a cylindrical portion 14a located on the outside in the depth direction and a semi-cylindrical portion 14b located on the inside in the depth direction compared to the cylindrical portion 14a. The cylindrical portion 14a of the shaft 14 is inserted into and fitted into the circular portion 23a. The semi-cylindrical portion 14b of the shaft 14 is inserted into and fitted into the semi-circular portion 23b. By fitting the semi-cylindrical portion 14b into the semi-circular portion 23b, the shaft 14 is fitted non-rotatably to the rigid portion 25 and the second support 61. As a result, the mouthpiece portion 20 is subjected to vibration from the gripping portion 10 via the shaft 14.

[0057] The shaft 14, which is inserted into and fitted into the fitting recess 23, is positioned further outward in the depth direction than the second support 61. Conventionally, in a mouthpiece-type toothbrush, the bearing portion is provided in the connecting portion 81 between the first support 31 and the second support 61. In this configuration, the connecting portion 81 becomes thicker at least in the circumferential center, resulting in a shallower bite. Furthermore, since a recess 32 is provided in the circumferential center, the number of first brush portions 41 is reduced in the circumferential range where the recess 32 is provided. This increases the risk of incomplete brushing, particularly at the gum line, as the entire tooth may not be brushed properly.

[0058] In contrast, by positioning the shaft 14 further outward in the depth direction than the second support 61, the connecting portion 81 can be made thinner. As a result, the first brush portion 41, the second brush portion 71, and the third brush portion 91 can firmly bite down so as to make contact with the entire tooth, allowing for brushing of the entire tooth without feeling any discomfort and while maintaining the effect of smooth brushing.

[0059] From the viewpoint of making the connecting portion 81 thin and allowing it to bite together firmly, the thickness of the connecting portion 81 in the meshing direction is preferably at least 5 mm or less in the circumferential range where the recess 32 is provided, more preferably 5 mm or less in the entire circumferential direction, and even more preferably 3 mm or less in the entire circumferential direction.

[0060] The second portion 25B is located inside the second support 61. The second portion 25B is U-shaped, following the shape of the second support 61. The second portion 25B is located in an area where the recess 32 is provided, at least in the circumferential direction. The second portion 25B is located in an area wider than the recess 32 on both the left and right sides in the circumferential direction, including the circumferential center.

[0061] The area of ​​the first support 31 where the recess 32 is provided in the circumferential direction has less resin compared to the surrounding area, making it prone to bending and becoming unstable in the event of brushing or vibration. In contrast, by providing a rigid second portion 25B in the area where a circumferential recess 32 is provided inside the second support 61, the first support can be stabilized via the connecting portion 81, and the bending of the first support 31 can be suppressed. As a result, brushing can be performed stably without causing any discomfort. Furthermore, as described above, the locations of the hard portion 25B and the recess 32 do not necessarily have to be on the first support 31 and on the second support 61; one may be on the first support 31 and the other on the second support 61.

[0062] As described above, in the mouthpiece portion 20 of this embodiment, the first support 31 has a recess 32 that is recessed downward from the upper end in the occlusal direction, and since the recess 32 is positioned to include the center in the circumferential direction, contact with the maxillary palate and the upper lip frenulum can be suppressed, and when the mouthpiece portion 20 is held in the mouth or moved from side to side for brushing, it is possible to brush smoothly without feeling any discomfort.

[0063] [Second embodiment of the mouthpiece portion 20] Next, a second embodiment of the mouthpiece portion 20 will be described with reference to Figures 8 and 9. In these figures, elements identical to those in the first embodiment shown in Figures 1 to 7 are denoted by the same reference numerals, and their descriptions are omitted.

[0064] Figure 8 is a view of the mouthpiece portion 20 of the second embodiment, seen from the inside in the depth direction. Figure 9 is a perspective view of the mouthpiece portion 20 of the second embodiment, seen from the inside in the depth direction. In the first embodiment, the first support 31 had a recess 32 that was recessed downward from the upper end in the biting direction. However, as shown in Figures 8 and 9, the mouthpiece portion 20 of this embodiment has recesses 33, 34, and 35 in addition to recess 32.

[0065] The recess 33 is recessed upward from the lower end in the meshing direction of the first support 31. The recess 33 is located in a position that includes the center in the circumferential direction. The maximum circumferential length and depth in the meshing direction of the recess 33 are the same as those of the recess 32.

[0066] In the first support 31 on the inside in the depth direction, a recess 33 is provided that extends upward from the lower end in the occlusal direction. This reduces the area that comes into contact with the floor of the mouth, the mandibular gingiva, or the buccal mucosa, thereby alleviating the feeling of pressure when the mouthpiece 20 is held in the mouth. When brushing by moving from side to side, the feeling of friction is also reduced, allowing for smoother brushing. Furthermore, in this embodiment, since the recess 33 is positioned to include the center in the circumferential direction, contact with the mandibular floor of the mouth can be suppressed. By suppressing contact with the mandibular floor of the mouth, it becomes possible to brush smoothly without feeling any discomfort when holding the mouthpiece portion 20 in the mouth and when moving it from side to side for brushing.

[0067] The recess 34 is recessed downward from the upper end in the meshing direction of the second support 61. The recess 34 is located in a position that includes the center in the circumferential direction. The recess 34 is formed with lengths equal to the circumferential center on both sides in the circumferential direction.

[0068] In the second support 61 on the outer side in the depth direction, a recess 34 is provided that extends downward from the upper end in the occlusal direction. This reduces the area that comes into contact with the upper lip frenulum, maxillary gingiva, or buccal mucosa, thereby alleviating the feeling of pressure when the mouthpiece 20 is held in the mouth. When brushing by moving from side to side, the feeling of friction is also reduced, allowing for smoother brushing. Furthermore, in this embodiment, since the recess 34 is positioned to include the center in the circumferential direction, contact with the upper lip frenulum can be suppressed. By suppressing contact with the upper lip frenulum, it becomes possible to brush smoothly without feeling any discomfort when holding the mouthpiece portion 20 in the mouth and when moving it from side to side for brushing.

[0069] In particular, since the upper lip frenulum is often longer than the lower lip frenulum, the provision of a recess 34 on the maxillary side of the second support 61 suppresses contact between the second support 61 and the upper lip frenulum, making it easier to achieve smooth brushing without feeling any discomfort.

[0070] As shown in Figure 1, if the total circumferential length L2 on the outer side in the depth direction of the second support 61 is taken as 100%, then, as shown in Figure 8, the maximum circumferential length L35 of the recess 34 is preferably 8% or more and 25% or less. If the circumferential end of the recess 34 is formed as a slope, the maximum circumferential length L35 of the recess 34 is defined by the circumferential length between the upper ends.

[0071] If the maximum length L35 is less than 8%, the relief of pressure is less noticeable, and the recess 34 cannot cover an area equivalent to one or two teeth in the circumferential direction, so the second support 61 may come into contact with the upper lip frenulum. In the circumferential area where the recess 34 is provided, the number of second brush parts 71 decreases, so if the maximum length L35 exceeds 25%, the cleaning power (brushing force) on the outer surface of the maxillary teeth may decrease. In addition, the stability when the mouthpiece part 20 is held in the mouth or moved from side to side is impaired. By setting the maximum length L35 to 8% or more and 25% or less, it is possible to maintain high cleaning power while maintaining the effect of smooth brushing without feeling discomfort.

[0072] The maximum length L35 is preferably between 10 mm and 20 mm. If the maximum length L35 is less than 10 mm, the relief of pressure may not be felt, and the recess 34 may not cover an area equivalent to one or two teeth in the circumferential direction, potentially causing the second support 61 to come into contact with the upper lip frenulum. If the maximum length L35 exceeds 20 mm, the number of second brush parts 71 decreases in the circumferential area where the recess 34 is provided, potentially reducing the cleaning power (brushing force) on the outer surface of the maxillary teeth. Furthermore, stability when holding the mouthpiece 20 in the mouth or moving it from side to side may be compromised. By setting the maximum length L35 to 10 mm or more and 20 mm or less, it is possible to maintain high cleaning power while maintaining the effect of smooth brushing without causing discomfort.

[0073] When the circumferential end of the recess 34 is formed by a slope, the intersection angle θ3 between the bottom of the recess 34 and the slope is preferably 90° or more and 160° or less, and more preferably 100° or more and 150° or less. If the intersection angle θ3 is less than 90°, the upper part of the recess 34 tends to be slightly closed, making it difficult to avoid contact with the upper lip frenulum. Also, because it becomes claw-shaped, if contact does occur, the resistance with the upper lip frenulum increases, resulting in greater discomfort. On the other hand, if the intersection angle θ3 exceeds 160°, the circumferential length of the upper end side forming the recess 34 becomes excessively long, and the area with less resin expands circumferentially, compromising stability during brushing. By having the intersection angle θ3 between the bottom of the recess 34 and the slope within the above range, the second support 61 is less likely to come into contact with the upper lip frenulum, or even if it does come into contact, the resistance with the upper lip frenulum can be reduced to the absolute minimum, allowing for smooth brushing without causing any discomfort.

[0074] L36 is defined as the distance (depth) between the uppermost position of the slope forming the recess 34 and the bottom of the recess 34. The distance L36 is preferably between 1.0 mm and 3.0 mm. If the distance L36 is less than 1.0 mm, the recess 34 becomes shallow, and the second support 61 may come into contact with the upper lip frenulum during brushing, potentially causing discomfort. Furthermore, the contact between the upper lip frenulum and the second support 61 may make it difficult to move the mouthpiece portion 20. If the distance L36 exceeds 3.0 mm, the number of second brush portions 71 decreases, potentially reducing the cleaning power (brushing force). By setting the distance L36 to between 1.0mm and 3.0mm, it is possible to maintain high cleaning power while ensuring smooth brushing without causing any discomfort.

[0075] The recess 35 is recessed upward from the lower end in the meshing direction of the second support 61. The recess 35 is located in a position that includes the center in the circumferential direction. The recess 35 is formed with lengths equal to the circumferential center on both sides in the circumferential direction.

[0076] In the second support 61 on the outer side in the depth direction, a recess 35 is provided that extends upward from the lower end in the occlusal direction. This reduces the area that comes into contact with the lower lip frenulum, mandibular gingiva, or buccal mucosa, thereby alleviating the feeling of pressure when the mouthpiece 20 is held in the mouth. When brushing by moving from side to side, the feeling of friction is also reduced, allowing for smoother brushing. Furthermore, in this embodiment, since the recess 35 is positioned to include the center in the circumferential direction, contact with the lower lip frenulum can be suppressed. By suppressing contact with the lower lip frenulum, it becomes possible to brush smoothly without feeling any discomfort when holding the mouthpiece portion 20 in the mouth and when moving it from side to side for brushing.

[0077] The maximum circumferential length L37 of the recess 35 is shorter than the maximum circumferential length L35 of the recess 34. When the circumferential end of the recess 35 is formed by a slope, the intersection angle θ4 between the bottom of the recess 35 and the slope is equivalent to the intersection angle θ3 of the recess 34. Therefore, the second support 61 is less likely to come into contact with the lower lip frenulum, or even if it does come into contact, the resistance with the lower lip frenulum can be reduced to the absolute minimum, allowing for smooth brushing without causing discomfort.

[0078] L38 is defined as the distance (depth) between the lowest point of the slope forming the depression 35 and the bottom of the depression 35. The distance L38 is equivalent to the distance L36 of the depression 34. This suppresses contact between the second support 61 and the lower lip frenulum, allowing for smooth brushing without causing discomfort, while maintaining high cleaning power. The other configurations are the same as those of the first embodiment described above.

[0079] In this embodiment, the mouthpiece portion 20 provides the same functions and effects as the first embodiment, but also has recesses 33, 34, and 35, which suppress contact with the mandibular floor of the mouth, the upper lip frenulum, and the lower lip frenulum. This makes it possible to brush more smoothly and with less discomfort when holding the mouthpiece portion 20 in the mouth and when moving it from side to side for brushing.

[0080] Preferred embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these examples. The shapes and combinations of the constituent members shown in the above examples are merely examples, and can be modified in various ways based on design requirements, etc., without departing from the spirit of the present invention.

[0081] For example, in the second embodiment described above, the mouthpiece portion 20 is shown to have a configuration in which recesses 33, 34, and 35 in addition to recess 32, but it is sufficient to have at least one of these recesses. Even in this case, it is preferable to have at least recess 32, which has the highest risk of contact.

[0082] Furthermore, although the above embodiment illustrates a configuration in which the recesses 32-35 are arranged in a position that includes the center in the circumferential direction, the configuration is not limited to this. The recesses 32-35 may be arranged in a position that does not include the center in the circumferential direction, or multiple recesses may be arranged in the circumferential direction, including positions that include the center in the circumferential direction as well as positions that do not include the center in the circumferential direction.

[0083] For example, as a modified version of the mouthpiece portion 20, as shown in Figure 10, by placing a recess 36 on the outer side (towards the molars) in the circumferential direction, the effect of avoiding contact not only with the gums and buccal mucosa but also with the retromolar triangle is enhanced, making it easier to move the mouthpiece 20 and allowing for brushing without feeling any discomfort.

[0084] Furthermore, although the above embodiment illustrates a configuration in which the second portion 25B of the rigid portion 25 is provided inside the second support 61, the configuration is not limited to this. The second portion 25B may be provided inside, for example, the first support 31, or inside both the first support 31 and the second support 61.

[0085] Furthermore, in the above embodiment, the first brush portion 41 and the second brush portion 71 may be filaments integrally molded with the first support 31 and the second support 61, respectively, or they may be bundles of bristles provided on the first support 31 and the second support 61, respectively.

[0086] Furthermore, although the above embodiment illustrates a configuration in which the toothbrush 1 has an electric drive unit in the gripping portion 10, it is not limited to this configuration. The toothbrush 1 may also be configured in which the gripping portion 10 does not have an electric drive unit, and the user manually applies vibration to the mouthpiece portion 20 via the gripping portion 10. [Explanation of Symbols]

[0087] 1...Toothbrush, 10...Holding part, 14...Shaft (axis part), 20...Mouthpiece part (connecting part), 22...Bearing part, 24...Indicator part, 25...Hard part, 30...First brush body, 31...First support, 32, 33, 34, 35, 36...Recess, 41...First brush part, 60...Second brush body, 61...Second support, 71...Second brush part, 80...Third brush body, 81...Connecting part, 91...Third brush part

Claims

1. The gripping part, A connecting body is connected to one side of the gripping portion in the depth direction perpendicular to the meshing direction, It has, The aforementioned connecting body, A first brush body located on one side in the depth direction from the gripping portion, A second brush body is positioned between the gripping portion and the first brush body in the depth direction, and is positioned away from the first brush body. It has, The first brush body is A first support is formed in a U-shape along the circumferential direction centered on the axis extending in the meshing direction, A first brush portion extending from the first support to the other side in the depth direction, It has, The second brush body is A second support formed in a U-shape along the circumferential direction, A second brush portion extending from the second support to one side in the depth direction, It has, A toothbrush in which at least one of the first support and the second support has a recess in the direction of occlusion extending from at least one of the ends on one side and the other side in the direction of occlusion.

2. The aforementioned recess is provided at least at the maxillary end in the occlusal direction, The toothbrush according to claim 1.

3. The recess is positioned at a location including the center in the circumferential direction, If the total length in the circumferential direction on one side in the depth direction of the first support is taken as 100%, The maximum length of the recess in the circumferential direction is 10% or more and 40% or less. The toothbrush according to claim 1 or 2.

4. At least one of the first support and the second support has a tapered shape in which the dimension in the meshing direction gradually decreases from the center in the circumferential direction towards the end. The toothbrush according to claim 1 or 2.

5. At least one of the first support and the second support is provided with a hard portion that is harder than at least one of the first support and the second support, at least in the area where the recess is provided in the circumferential direction. The toothbrush according to claim 1 or 2.

6. The gripping portion has a shaft portion extending to one side in the depth direction, The second support has a bearing portion on which the shaft portion is mounted, The shaft portion is positioned further to the other side in the depth direction than the second support. The toothbrush according to claim 1 or 2.

7. The region where the second support and the bearing portion are connected is The dimension in the meshing direction is longer than the maximum dimension of the recess in the meshing direction. The end on one side in the circumferential direction is located further to the other side in the circumferential direction than the end on the other side in the circumferential direction in the recess, The other end in the circumferential direction is located further to the other side in the circumferential direction than the other end in the circumferential direction of the recess. The toothbrush according to claim 6.

8. The first brush body and the second brush body have an indicator portion that serves as an indicator of the position in the meshing direction, The toothbrush according to claim 1 or 2.

Images