JPH07116023A - Motor-driven toothbrush - Google Patents

Abstract

PURPOSE:To convert rotation force to reciprocal rotation movement with a large rotation angle by making a cam follower connected to a drive shaft through a crank engage with a sine-shaped groove of cylindrical groove cam. CONSTITUTION:A cylindrical groove cam 29 made in the form of sine shape along the outer circumferential face of a groove 28 having a rectangular section is arranged at a face gear 27 in a coaxial manner. At base end of a brush drive shaft 31 a rod-like cam follower 33 having a circular section is arranged through a crank member 32, and the tip is engaged with the inside of the groove 28 of the cam 29. When an output shaft 20 of a motor 16 is turned counterclockwise seen from the tip, the cam 29 is rotated in the arrow direction through a pinion gear 21 and the face gear 27. Following to the rotation of the cam 29 the cam follower 33 is moved periodically in the axial direction of the cam 29, and the movement of the cam follower is transmitted as reciprocal movement to a brush drive shaft 31 through the crank member 32. With the selection of amplitude in the axial direction of the cam groove 28 the rotation angle of the shaft 31 is made to be a required level.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric toothbrush having a drive converting mechanism for converting a continuous rotary motion of a motor into a reciprocating rotary motion for driving a brush. Further, the present invention is
The present invention also relates to an electric toothbrush having a drive conversion mechanism that converts a continuous rotary motion of a motor into a combined motion of a reciprocating rotary motion and a reciprocating linear motion for driving a brush.

[0002]

2. Description of the Related Art Electric toothbrushes having a mechanism for converting a continuous rotation output of a motor into a reciprocating rotary motion for driving a brush are known. For example, in U.S. Pat.No. 3,533,119, a gear that includes an eccentric pin and that is continuously rotated by the output of a motor and a fork-shaped member that is fixed to a brush drive shaft and that engages with the eccentric pin are provided. There is disclosed a drive conversion mechanism in which the brush drive shaft is reciprocally rotated in accordance with the rotation. Further, in U.S. Pat.No. 3,623,175, a disk having a zigzag-shaped groove on its outer peripheral surface and driven to rotate by a mainspring, and an elliptical shape extending from the end of the brush drive shaft to be engaged in the groove are disclosed. There is disclosed a drive conversion mechanism in which a rod-shaped member having a cross section is provided, and the brush drive shaft is reciprocally rotated as the disk rotates.

On the other hand, in recent years, an electric toothbrush having a circular brush reciprocally rotating at its tip has been proposed. by the way,
In order to obtain a sufficient brushing effect in this type of electric toothbrush, it is necessary to increase the rotation angle of the circular brush (several tens of degrees or more, preferably 100 degrees or more).
However, it is difficult to obtain such a large rotation angle by using the conventional drive conversion mechanism as described above.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an electric toothbrush having a drive conversion mechanism capable of converting continuous rotation output of a motor into reciprocating rotary motion having a sufficiently large rotation angle. Especially. Also,
Another object of the present invention is to provide an electric toothbrush which has the above-described drive converting mechanism and which can bend the toothbrush portion with respect to the electric toothbrush main body portion. Still another object of the present invention is a drive conversion mechanism as described above, which has a drive conversion mechanism capable of applying axial reciprocating motion to the toothbrush portion in addition to reciprocating rotary motion. To provide a toothbrush. To achieve the above object, an electric toothbrush according to the present invention converts a rotational movement of a motor provided in a main body, a brush drive shaft having a brush connected to one end thereof, and a reciprocating rotational movement of an output shaft of the motor. An electric toothbrush having a drive converting mechanism for transmitting to the other end of the brush drive shaft, the rotatably supported by the main body about an axis extending in a direction substantially orthogonal to the longitudinal direction of the main body. A cylindrical groove cam, which is connected to the output shaft of the motor and is driven to rotate, and has a substantially sign-shaped groove formed on the outer peripheral surface in the circumferential direction, is connected to the main body, and the brush drive shaft is A supporting member that supports the cylindrical groove cam such that the shaft can rotate in a direction substantially orthogonal to the rotating shaft and that restricts the movement in the axial direction, and the other end of the brush driving shaft is connected via a crank and Cylinder It is characterized in that which is configured by providing the cam follower which engages the groove of the cam, the.

According to the above construction, by selecting the amplitude of the sine-shaped groove formed on the cylindrical groove cam in the axial direction of the cylindrical groove cam, the rotation angle of the reciprocating rotary motion of the brush drive shaft can be set to an arbitrary value. It is possible to choose, theoretically up to a little less than 180 degrees of rotation angle without losing the conversion function. The cylindrical groove cam in this configuration may be provided coaxially with the face gear on a face gear that meshes with a pinion attached to the output shaft of the motor. If the support member is rotatably connected to the main body via the rotary shaft of the cylindrical groove cam, the toothbrush including the brush and the brush drive shaft is not adversely affected in the operation of the drive conversion mechanism. The part can be bent with respect to the main body. The brush in this configuration is preferably a circular brush provided at the tip of the brush drive shaft so as to be rotatable around an axis orthogonal to the drive shaft.

In the electric toothbrush according to the present invention, in which the brush is driven by a combined motion of reciprocating rotary motion and reciprocating linear motion, the drive converting mechanism is provided in the main body substantially orthogonal to the longitudinal direction of the main body. A cylindrical groove cam that is eccentrically supported around the shaft and is rotationally driven by being connected to an output shaft of a motor, and has a substantially sine-shaped groove formed on an outer peripheral surface in the circumferential direction; A support that is connected to the main body and that supports the brush drive shaft so as to be axially rotatable in a direction substantially orthogonal to the eccentric rotation axis of the cylindrical groove cam and through an urging means that urges in the cylindrical groove cam direction. A member and a cam follower that is connected to the other end of the brush drive shaft via a crank and engages with the groove of the cylindrical groove cam;
It is characterized by being provided with.

According to this structure, the rotation angle of the reciprocating rotary motion of the brush drive shaft can be arbitrarily selected to a value slightly smaller than 180 degrees by the amplitude of the sine-shaped groove formed on the cylindrical groove cam, and the reciprocating motion can be performed. The stroke of linear movement can be selected according to the degree of eccentricity of the cylindrical groove cam. The cylindrical groove cam in this configuration may be provided on a face gear that meshes with a pinion attached to the output shaft of the motor, eccentrically with respect to the rotation shaft of the face gear. Further, if the support member is rotatably connected to the main body via the rotation shaft of the face gear, the toothbrush portion is bent with respect to the main body without any adverse effect on the operation of the drive conversion mechanism. It becomes possible.

[0008]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

1 and 2 show the configuration of a first embodiment of an electric toothbrush according to the present invention. This electric toothbrush 10 has a main body 11 to be gripped by a user's hand, and two circular brushes 12 and 13 at the tip end, which are rotatably connected to the tip end of the main body part 11 within a predetermined angle. The toothbrush portion 14 is formed. In this case, the toothbrush portion 14
Is always bent by a predetermined angle to the main body 11 toward the brushes 12 and 13 by a biasing means such as a spring (not shown).
When 13 is pressed against the gums or the like with an excessive force, it is rotated to the back side, whereby excessive pressing of the brush is prevented. When the toothbrush portion 14 is rotated up to the extension line of the main body portion 11, it is locked by means not shown,
It does not rotate any further.

A substantially cylindrical housing 15 of the body 11
Inside, there is a motor 16 and a battery 1 which is the power source for this motor.
7 and a circuit unit 18 including a charging circuit for the battery and other necessary electronic circuits are provided, and the motor 16 is driven by the output of the battery 17 when a switch 19 provided on the housing 15 is closed. It is supposed to be done. It should be noted that in the drawings, wirings and the like between the above-mentioned respective parts are omitted for simplification.

The output shaft 20 of the motor 16 extends through the opening of the end wall 15a of the housing 15, and a pinion gear 21 is attached to the tip of the output shaft 20. Further, two supporting walls 22 facing each other are provided at the tip of the housing 15.
22 are integrally formed, and a shaft 23 is provided so as to pass through these walls in a direction orthogonal to the motor shaft 20. A large-diameter cylindrical portion 25 on the base end side of the toothbrush portion 14 is connected to both ends of the shaft 23, and thus the toothbrush portion 14 is rotatable around the shaft 23 with respect to the main body portion 11.

As enlargedly shown in FIGS. 3 and 4, a face gear 27 that meshes with the pinion gear 21 is rotatably provided on the shaft 23. The face gear 27 is coaxially provided with a cylindrical groove cam 29 in which a groove 28 having a rectangular cross section is formed in a sine shape along the outer peripheral surface. On the other hand, a rod-shaped cam follower 33 having a circular cross section is provided at the base end of a brush drive shaft 31 extending inside the small-diameter cylindrical portion 30 of the toothbrush portion 14 via a crank member 32. Groove cam 2
9 in the groove 28.

A brim-shaped locking portion 34 is formed on the brush drive shaft 31 of the toothbrush portion 14, and the movement of the drive shaft 31 in the distal direction is restricted by the locking portion 34. There is. Further, circular brushes 13 and 12 are sequentially connected to a tip end portion of the brush drive shaft via a gear (not shown), so that when the drive shaft 31 rotates, the brushes 12 and 13 rotate in mutually opposite directions. It is like this.

Sealing members 35 and 36 are provided at the opening of the end wall 15a of the main body 11 and the base end of the small diameter cylindrical portion 30 of the toothbrush portion 14, respectively, and the tubular portion of the housing 15 is provided. The peripheral portion of the tip and the peripheral portion of the base end of the large-diameter cylindrical portion 25 of the toothbrush portion 14 are covered with a cylindrical elastic member 37, which prevents water and the like from entering each interior. Although the toothbrush portion 14 is integrally shown in the drawing, the toothbrush portion can be separated into the proximal end side and the distal end side, so that only the distal end side can be replaced.

In the above structure, when the switch 19 is turned on and the output shaft 20 of the motor 16 rotates counterclockwise when viewed from the tip end side, this rotation causes the cylindrical groove cam 29 via the pinion gear 21 and the face gear 27. It is rotated in the direction shown by the arrow in FIG. The cam follower 33 periodically moves in the axial direction of the cam 29 in accordance with the rotation of the cylindrical groove cam 29, and the motion of the cam follower 33 is changed by the crank member 32.
Is transmitted to the brush drive shaft 31 as a reciprocating rotary motion. As a result, the circular brushes 12 and 13 each perform reciprocating rotary motion. According to this configuration, the rotation angle of the brush drive shaft 31 can be set to a desired value by appropriately selecting the amplitude of the cam groove 28 in the axial direction of the cylindrical groove cam 29. In this case, theoretically this rotation angle is 180
The value can be set to a value slightly smaller than the degree, but in order to obtain a smooth reciprocating rotational movement of the drive shaft 31, it is desirable to limit the value to about 140 degrees at the maximum.

Further, according to the above construction, the toothbrush portion 14
Even if is rotated with respect to the main body portion 11, since the rotation axis is the same as the rotation axis of the face gear 27, the drive conversion function is not affected at all. The toothbrush portion 14
If the rotation function of the toothbrush is unnecessary, the cylindrical portion 2 of the toothbrush portion 14
5 may be fixed to the main body housing 15 or formed integrally with the housing.

Next, a second embodiment of the electric toothbrush according to the present invention will be described.

This electric toothbrush 110 shown in FIG. 5 and FIG.
The structure is substantially the same as that of the embodiment shown in FIGS. 1 and 2 except for the drive conversion mechanism and the toothbrush part, and corresponding parts are denoted by reference numerals increased by 100 and description thereof is omitted. A cylindrical groove cam 129 is eccentrically attached to the shaft 123 on the face gear 127 of the electric toothbrush 110.
This drive conversion mechanism is covered by a cover 125 rotatably supported by a shaft 123 on the main body 111. As shown in detail in FIGS. 7 and 8, a brim-shaped locking portion 140 is formed on the brush drive shaft 131 in this embodiment, and this locking portion 140 and the inner wall of the tip portion of the cover 125 are formed. A spring 141 is provided between them. Thus, the brush drive shaft 1
Therefore, the cam follower 133 is always biased toward the cylindrical groove cam 129. The output shaft 131
A toothbrush portion 114 having a brush 112 is detachably attached to the tip of the.

According to the drive converting mechanism having the above structure, the cam follower 133 reciprocates in the axial direction of the cam 129 and in the direction orthogonal to this axis as the cylindrical groove cam 129 rotates.
The output shaft 131 performs a combined motion of reciprocating rotary motion and axial reciprocating linear motion. In this case, the rotation angle of the reciprocating rotary motion depends on the amplitude of the sine-shaped cam groove 128 formed on the cylindrical groove cam 129, and the stroke of the reciprocating linear motion determines the cylindrical groove cam 129.
Can be arbitrarily selected depending on the degree of eccentricity with respect to the face gear 127. Also in this configuration, even if the toothbrush portion 114 is rotated with respect to the main body portion 111, since the rotation axis is the same as the rotation axis of the face gear 127, the drive conversion function is not adversely affected at all. . When the function of rotating the toothbrush portion 114 with respect to the main body portion 111 is unnecessary, the cover 125 may be fixed to the housing 115 of the main body portion 111 or formed integrally with the housing.

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view showing a first embodiment of an electric toothbrush according to the present invention,

FIG. 2 is a side view of the embodiment,

FIG. 3 is an enlarged plan view showing a main part of a drive conversion mechanism used in the embodiment.

FIG. 4 is a side view of the drive conversion mechanism,

FIG. 5 is a plan view showing a second embodiment of an electric toothbrush according to the present invention with a part cut away;

FIG. 6 is a side view of the embodiment,

FIG. 7 is an enlarged plan view showing a main part of a drive conversion mechanism used in the embodiment.

FIG. 8 is a side view of the drive conversion mechanism.

[Explanation of symbols]

10 ... Electric toothbrush, 11 ... Main body part, 1
2, 13 ... Brush, 14 ... Toothbrush part,
16 ... Motor, 20 ... Motor output shaft, 21 ... Pinion gear, 23 ... Shaft,
25 ... Cylindrical part, 27 ... Face gear, 28 ... Groove, 29 ... Cylindrical groove cam, 31 ... Brush drive shaft.

Claims (7)

[Claims] 1. A motor provided inside the main body, a brush drive shaft to which a brush is connected at one end, and a rotary motion of an output shaft of the motor is converted into a reciprocating rotary motion, and the other end of the brush drive shaft is converted. An electric toothbrush having a drive converting mechanism for transmitting, wherein the main body is rotatably supported by the main body about an axis extending in a direction substantially orthogonal to a longitudinal direction of the main body, and is connected to an output shaft of the motor. A cylindrical groove cam that is rotatably driven and has a substantially sine-shaped groove formed on the outer peripheral surface along the circumferential direction; and a brush drive shaft that is connected to the main body and that rotates the brush drive shaft with respect to the rotary shaft of the cylindrical groove cam. A support member that supports the shaft in a substantially orthogonal direction so as to be rotatable and regulates the movement in the axial direction, and is connected to the other end of the brush drive shaft via a crank and engages with the groove of the cylindrical groove cam. With cam followers An electric toothbrush characterized by having. 2. The electric toothbrush according to claim 1, wherein the cylindrical groove cam is provided on a face gear that meshes with a pinion attached to an output shaft of the motor, coaxially with the face gear. And an electric toothbrush. 3. The electric toothbrush according to claim 1 or 2, wherein the support member is rotatably connected to the main body by a rotation shaft of the cylindrical groove cam. electric toothbrush. 4. The electric toothbrush according to claim 1, claim 2, or claim 3, wherein the brush is provided at the tip of the brush drive shaft so as to be rotatable around an axis orthogonal to the drive shaft. An electric toothbrush having at least one circular brush. 5. A motor provided inside the main body, a brush drive shaft having a brush connected to one end, and a rotary motion of an output shaft of the motor are converted into a combined motion of reciprocating rotary motion and reciprocating linear motion. An electric toothbrush having a drive converting mechanism for transmitting to the other end of the brush drive shaft, the electric toothbrush being supported by the main body so as to be eccentrically rotated about an axis substantially orthogonal to the longitudinal direction of the main body. A cylindrical groove cam that is connected to the output shaft of the motor and is driven to rotate, and has a substantially sign-shaped groove formed on the outer peripheral surface in the circumferential direction; A support member rotatably supported in a direction substantially orthogonal to the eccentric rotation axis of the cylindrical groove cam via an urging means for urging in the cylindrical groove cam direction, and a crank at the other end of the brush drive shaft. Connected through An electric toothbrush having a cam follower that engages with the groove of the cylindrical groove cam. 6. The electric toothbrush according to claim 5, wherein the cylindrical groove cam is provided on a face gear that meshes with a pinion attached to an output shaft of the motor, and is eccentric to a rotation shaft of the face gear. An electric toothbrush characterized by that. 7. The electric toothbrush according to claim 5 or 6, wherein the support member is rotatably connected to the main body by an eccentric rotation shaft of the cylindrical groove cam. Electric toothbrush to do.