JP2565883Y2 - electric toothbrush - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to an electric toothbrush.
In particular, the present invention relates to an electric toothbrush having an improved replacement brush mounting structure.

[0002]

2. Description of the Related Art Generally, as an electric toothbrush, a vibration method in which an eccentric weight is rotationally driven by an electric motor to apply vibration to the replacement brush, and a reciprocating movement of the brush by changing the rotation of the electric motor via a crank mechanism or the like. There is known a reciprocating system that converts the data into a reciprocating motion. In the electric toothbrush,
Brushing is performed by pressing the brush against the teeth while vibrating or reciprocating the replacement brush, but depending on the user, the brush may be manually brushed while vibrating or reciprocating the replacement brush electrically. On the other hand, the replacement brush needs to be fixed and held sufficiently firmly.

For this reason, in the vibration type electric toothbrush, for example, as described in Japanese Utility Model Laid-Open No. 5-4918,
A cylindrical pedestal is formed at one end of the casing of the electric toothbrush body in a protruding shape, and a shaft is formed at the center of the pedestal so as to protrude coaxially with the pedestal. There is a configuration in which a pair of large and small fitting recesses for external fitting are formed coaxially, and the pedestal and the shaft are press-fitted into the fitting recesses to fix and hold the replacement brush in the casing.

In the reciprocating electric toothbrush, for example, as described in Japanese Patent Publication No. 54-26937, a reciprocating drive shaft is provided at one end of an electric toothbrush main body in a protruding manner, and a replacement brush is provided. An outer cylinder is formed coaxially on the outer end of the inner cylinder and the inner cylinder that can be fitted to the drive shaft at the base end of the outer cylinder,
The inner cylinder is divided into two parts, and one half cylinder and the outer cylinder are connected by a reinforcing rib, and a bending prevention rib for preventing bending of the other half cylinder is formed in a part of the outer cylinder facing the other half cylinder. An engaging projection is formed on the inner peripheral portion of the other half cylinder to engage with an engagement recess formed on the drive shaft, and while the other half cylinder is slightly elastically deformed, the drive shaft is moved inside. The replacement brush is attached to the cylinder so that the engagement recess engages with the engagement protrusion, and the replacement brush is fixed and held immovable in the axial direction with respect to the drive shaft, and is oriented in a direction perpendicular to the brush installation surface acting during brushing. Is configured to be effectively received by one half cylinder and the outer cylinder.

[0005]

In the former electric toothbrush, since the base end of the replacement brush is externally fitted to the base and the shaft, the contact area between the casing and the replacement brush is increased to reduce the vibration of the casing. The brush can be transmitted sufficiently to the replacement brush, but the thickness of the base end of the replacement brush is increased, so that uneven wall thickness easily occurs during molding, and the movement of the replacement brush in the axial direction is fitted to the pedestal and shaft. Since the brush depends on the frictional resistance between the concave portions, there is a problem that the replacement brush may fall off when the brush is manually brushed in the axial direction.
Further, similarly to the reciprocating electric brush, an engaging recess is formed in the shaft portion or the pedestal, and an engaging projection is formed on the inner peripheral surface of the fitting recess of the replacement brush. However, in this case, it is necessary to make the base end of the replacement brush radially expandable, and the strength and rigidity of the base end of the replacement brush are greatly reduced. There is a problem that transmission of vibration is reduced.

On the other hand, in the latter electric toothbrush, since the engagement projection of the inner cylinder is engaged with the engagement recess of the drive shaft, the replacement brush can be moved even if the replacement brush is moved in the axial direction of the drive shaft. However, when this replacement brush is applied to a vibration-type electric toothbrush, the other half of the inner cylinder is elastically deformed by vibration, and the engagement between the engagement projection and the engagement recess is released. However, the replacement brush may fall off the drive shaft, and the other half cylinder may be elastically deformed to absorb vibration and not transmit enough vibration to the replacement brush. is there. An object of the present invention is to provide an electric toothbrush that can effectively prevent the replacement brush from falling off and can efficiently transmit vibration and reciprocating motion to the replacement brush.

[0007]

According to a first aspect of the present invention, there is provided an electric toothbrush having a cylindrical pedestal formed at one end in a protruding shape, and a shaft formed at the center of the pedestal so as to protrude coaxially with the pedestal. A casing and a replacement brush detachably attached to the casing, wherein an outer cylinder which can be externally fitted to a pedestal at a base end side and a coaxial shape through an annular groove inside a rear end side part of the outer cylinder. And a replacement brush which has an inner cylinder which can be externally fitted to the shaft portion and which can be engaged with the shaft portion in a non-movable manner in the axial direction through a concave-convex relationship with the shaft portion. .

According to a second aspect of the present invention, there is provided an electric toothbrush comprising: a drive shaft protrudingly provided at one end of a casing; a disk-shaped pedestal fixed coaxially with the drive shaft at an intermediate portion of the drive shaft; A replacement brush detachably attached to the drive shaft and the pedestal, an outer cylinder that can be externally fitted to the pedestal at a base end portion, and a coaxial shape through an annular groove inside a rear end side portion of the outer cylinder. And a replacement brush which is engageable with the drive shaft in a non-movable manner in the axial direction through a concave-convex relationship with the drive shaft. .

Here, a portion of the annular groove opposite to the portion on the side where the brush of the replacement brush is planted in the annular groove may be formed as a shallow groove. As described in Item 4, the inner cylinder is divided into a pair of half cylinders on the brush implantation surface side and the opposite side through a pair of slits, and the half cylinder on the brush implantation surface side is a shaft portion or The drive shaft may be immovably engaged with the drive shaft in the axial direction through a concave-convex relationship.

[0010]

In the electric toothbrush according to the first aspect, an outer cylinder formed at the base end portion of the replacement brush and an inner cylinder formed coaxially through an annular groove inside the inner end portion of the outer cylinder. The tube is externally fitted to a pedestal and a shaft formed at one end of the casing, and the replacement brush is detachably fixed and held to the casing. Here, since the inner cylinder is immovably engaged with the shaft portion via the unevenness in the axial direction, the relative movement of the replacement brush and the casing in the axial direction is restricted. In addition, the inner cylinder is configured to be able to expand in diameter by being divided, for example, and has relatively elasticity. However, since the outer cylinder is mounted on the pedestal, the vibration of the casing is almost attenuated. It is transmitted to the replacement brush without doing. Furthermore, since the annular groove is formed between the inner cylinder and the outer cylinder, it is possible to make the base end portion of the replacement brush relatively thin.

[0011] In the electric toothbrush according to the second aspect,
An outer cylinder formed at the base end portion of the replacement brush and an inner cylinder formed coaxially through an annular groove inside the inner end portion of the outer cylinder are fixed to a middle portion of the drive shaft. The replacement brush is mounted on the plate-shaped pedestal and the drive shaft so as to be externally fitted to the casing, and the replacement brush is detachably fixed to the casing. Here, since the inner cylinder is immovably engaged with the drive shaft in the axial direction through the unevenness relationship, the relative movement of the replacement brush and the drive shaft in the axial direction is restricted. In addition, the inner cylinder is configured to be able to expand in diameter by being divided or the like, and has relatively elasticity. However, since the outer cylinder is mounted on the pedestal in an outer fitting shape, the vibration of the casing is almost eliminated. It is transmitted to the replacement brush without attenuation. Further, since the annular groove is formed between the inner cylinder and the outer cylinder, it is possible to make the base end of the replacement brush relatively thin.

In the third aspect, the shallow groove side portion of the inner cylinder is reinforced, and the load acting on the replacement brush at the time of brushing and directed in the direction perpendicular to the brush installation surface is effectively received by the inner cylinder. . In claim 4, the inner cylinder expands and contracts in the direction perpendicular to the brush implantation surface, and the half cylinder on the implantation surface side engages with the shaft portion or the drive shaft through a concave-convex relationship, thereby forming the inner cylinder. It is externally fitted to the shaft portion or the drive shaft so as not to be relatively movable in the axial direction.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG.
Includes a casing 3 in which the vibration generating means 2 is incorporated, and a replacement brush 4 detachably attached to the left end of the casing 3. The vibration generating means 2 is fixed to a battery 5 coaxially mounted on the casing 3, an electric motor 6 fixed in the right end of the casing 3, and a rotating shaft 6 a protruding rightward of the electric motor 6. Eccentric weight 7
And a switch (not shown) interposed in the middle of the wiring of the power supply system to the electric motor 6. When the switch is turned on, the eccentric weight 7 is rotationally driven by the electric motor 6, and the centrifugal force of the eccentric weight 7 causes the casing to rotate. The entire casing 3 is configured to vibrate around the left end of the casing 3.

The casing 3 will be described. As shown in FIGS. 1 to 3, the casing 3 is formed of a substantially cylindrical member, and a wall 3a is integrally formed on the right end of the casing 3 to form the casing 3. The right end is closed and the wall 3a
A column-shaped pedestal 8 is formed to protrude rightward.
A shaft 9 extending rightward is formed coaxially with the pedestal 8 at the center of the shaft, and a pair of upper and lower engaging recesses 9 is formed near the left end of the shaft 9.
a is formed, and a flat plate-shaped rotation restricting portion 9 is formed on the right portion of the shaft portion 9.
b is formed.

The replacement brush 4 will be described. As shown in FIGS. 1 to 4, a substantially flat planting surface 10 is formed on the upper surface of the right end of the replacement brush 4, and the planting surface 10 is directed upward. A protruding brush 11 is implanted, and the replacement brush 4
A connecting portion (which corresponds to a base end portion) 4a bulging along the outer surface of the casing 3 is formed on the left portion of
An outer cylinder 12 that can be externally fitted to the pedestal 8 is provided at the left end of the connecting portion 4a.
Is formed inside the right half of the outer cylinder 12 so as to be coaxial with the outer cylinder 12 through an annular groove 14 so that the inner cylinder 13 can be externally fitted to the shaft portion 9. Upper half cylinder 13a and lower half cylinder 13b through a pair of front and rear slits 15 extending
An engagement projection 13c that can be engaged with the engagement recess 9a is formed in a protruding shape near the left end of the inner peripheral surface of the upper half cylinder 13a, and the upper half 14a of the annular groove 14 is Lower half 14b
In the vicinity of the left end of the replacement brush 4, a fitting recess 16 engageable with the rotation regulating portion 9 b is formed in a deeper groove than the inner cylinder 13.
Is formed continuously with the internal space 17.

Next, the operation of the electric toothbrush 1 will be described. The outer cylinder 12 and the inner cylinder 13 of the replacement brush 4 are
And the shaft portion 9 are externally fitted to each other, and the replacement brush 4 is fixed to the casing 3 so as to be detachably fixed. In this state, the switch is turned ON to drive the electric motor 6 to change the vibration of the casing 3. The teeth are transmitted by the brush 4 and the teeth are brushed using the vibration of the brush 11.

Since the outer tube 12 and the inner tube 13 are mounted on the pedestal 8 and the shaft portion 9, respectively, the contact area between the casing 3 and the replacement brush 4 is increased to effectively reduce the vibration of the casing 3. Can be transmitted to the brush 4 instead. Also, the inner cylinder 13 includes upper and lower half cylinders 13a and 13b.
The outer cylinder 12 is mounted on the pedestal 8 so that the vibration of the casing 3 is almost attenuated. It is transmitted to the replacement brush 4 without performing. Further, an engagement recess 9a that can be engaged with an engagement protrusion 13c formed on the outer peripheral surface of the shaft portion 9 is formed on the inner peripheral surface of the inner cylinder 13, so that the replacement brush 4 for the shaft portion 9 is formed. Relative movement in the axial direction is reliably restricted, and the replacement brush can be reliably prevented from falling off during brushing.

Since the annular groove 14 is formed between the inner cylinder 13 and the outer cylinder 12, the thickness of the base end of the replacement brush 4 can be made relatively thin, and the replacement brush 4 can be formed at the time of molding. Of the connecting portion 4a can be prevented. Further, since the upper half portion 14a of the annular groove 14 is formed as a deep groove, the engagement and disengagement between the engagement projection 13c and the engagement recess 9a can be performed relatively easily, and the lower half portion of the annular groove 14 can be formed. 14b is formed in a shallow groove, so that the planting surface 1 acting during brushing
It is possible to effectively receive a load in the orthogonal direction of 0.

In this embodiment, the present invention is applied to the vibration type electric toothbrush 1, but the present invention can be similarly applied to a reciprocating electric toothbrush. That is, as shown in FIG. 5, the casing 3 is provided with a drive shaft 9A extending in a protruding left direction so as to be movable in the left-right direction with respect to the casing 3A, and the drive shaft 9A is provided in the casing 3A. The motor is reciprocated left and right by an electric motor via an external crank mechanism or the like. A disk-shaped pedestal 8A is provided in the middle of the drive shaft 9A, and the inner cylinder 13 of the brush 4 is replaced with the drive shaft 9A and the pedestal 8A. And the outer cylinder 12 is fitted in an outer fitting shape,
The brush 4 may be removably attached to the drive shaft 9A.

[0020]

As described in detail in the above section, the following effects can be obtained. According to the electric toothbrush according to the first aspect, the inner cylinder is immovably engaged with the shaft portion in the axial direction via the unevenness, so that the replacement brush is securely prevented from coming off in the axial direction. That is, since the outer cylinder and the inner cylinder are mounted on the pedestal and the shaft portion, respectively, so that the vibration of the casing can be transmitted to the replacement brush with almost no attenuation, and the outer cylinder is attached to the pedestal. Since the inner cylinder is mounted in an outer fitting shape and elastic deformation of the inner cylinder is suppressed, it is possible to effectively prevent the engagement of the inner cylinder and the shaft portion through the concave-convex relationship from being released by the vibration of the casing. Since the annular groove is formed between the outer brush and the outer cylinder, the thickness of the proximal end of the replacement brush can be made relatively thin, and the uneven thickness of the proximal end of the replacement brush during molding can be prevented. The pedestal and the shaft are formed in a protruding shape at one end of the casing. Since cleaning of the vicinity of the base and the shaft portion to be simple, effects such as can be obtained.

According to the electric toothbrush according to the second aspect, the inner cylinder is immovably engaged with the drive shaft in the axial direction through the unevenness, so that the replacement brush can be securely removed in the axial direction. Since the outer cylinder and the inner cylinder are mounted on the pedestal and the drive shaft, respectively, in the form of external fitting, the contact area between the electric toothbrush body and the replacement brush is increased to increase the mounting strength and rigidity of the replacement brush. Since the outer cylinder is mounted on the pedestal so as to be fitted to the pedestal and elastic deformation of the inner cylinder is suppressed, the engagement between the inner cylinder and the shaft via the concave-convex relationship is released by the vibration of the casing. Is effectively prevented, and since the annular groove is formed between the inner cylinder and the outer cylinder, the thickness of the base end of the replacement brush can be made relatively thin. The effect of preventing uneven thickness at the base end is obtained. It is.

According to the third aspect, it is possible to effectively receive the load acting on the replacement brush in the direction perpendicular to the brush installation surface at the time of brushing at the shallow groove side portion of the inner cylinder. The mounting strength can be further increased. According to the fourth aspect, the engagement of the half-cylinder on the planting surface side with the shaft portion or the drive shaft through the concave-convex relationship is released by the load acting on the replacement brush in the direction perpendicular to the brush-placing surface during brushing. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of an electric toothbrush.

FIG. 2 is a longitudinal sectional view of the electric toothbrush.

FIG. 3 is a cross-sectional view of the electric toothbrush.

FIG. 4 is a sectional view taken along line 4-4 in FIG. 2;

FIG. 5 is a diagram corresponding to FIG. 1 of an electric toothbrush according to a modification.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric toothbrush 8 Pedestal 9 Shaft part 3 Casing 3A Casing 4 Replacement brush 9 Shaft part 9a Engaging recess 9A Drive shaft 10 Implantation surface 11 Brush 12 Outer cylinder 13 Inner cylinder 13a Half cylinder 13b Half cylinder 13c Engagement projection 14 Ring Groove 15 Slit

Claims (4)

(57) [Scope of request for utility model registration] 1. A casing in which a cylindrical pedestal is formed in a protruding shape at one end and a shaft is formed in a central portion of the pedestal so as to protrude coaxially with the pedestal, and a replacement brush detachably attached to the casing. An outer cylinder that can be externally fitted to the pedestal at the base end portion and an inner cylinder that is formed coaxially through an annular groove inside the outer end side portion of the outer cylinder and that can be externally fitted to the shaft portion An electric toothbrush, comprising: a replacement brush having an inner cylinder and an inner cylinder that is non-movably engageable in the axial direction through a concave-convex relationship with the shaft portion. 2. A drive shaft protrudingly provided at one end of a casing, a disk-shaped pedestal fixed coaxially with the drive shaft at an intermediate portion of the drive shaft, and detachably attached to the drive shaft and the pedestal. A replacement brush that is attached so as to be capable of being fitted to the base, and is formed coaxially through an annular groove inside an outer cylinder that can be externally fitted to the pedestal and a rear end portion of the outer cylinder, and is formed outside the drive shaft. An electric toothbrush comprising: a replaceable brush having a fittable inner cylinder, and the inner cylinder being non-movably engageable with the drive shaft in an axial direction through a concave-convex relationship. 3. The shallow groove is formed in a portion of the annular groove opposite to a portion of the replacement brush on the side where the brush is to be planted. Electric toothbrush. 4. The brush according to claim 1, wherein the inner cylinder is divided into a pair of half-cylinders on a brush-implanting surface side and an opposite side through a pair of slits, and the half-cylinder on the brush-implanting surface side is a shaft portion or a driving unit. The electric toothbrush according to claim 1, 2 or 3, wherein the electric toothbrush is immovably engaged with the shaft in the axial direction through a concave-convex relationship.