PH12018000409A1 - Electric toothbrush - Google Patents

Abstract

An electric toothbrush including a body, a brush, and a vibration assembly is provided. The vibration assembly includes a power source disposed in the body, a transmission shaft having a first end and a second end opposite to each other, and a weight block. The first end connected to the power source is located on a first axis together with the power source, and the second end extends outside the body. The weight block disposed on the second end is located on a second axis together with the second end. The brush is movably assembled to the body and is sleeved on the weight block. When the power source drives the first end of the transmission shaft to rotate about the first axis, the second end rotates around the first axis, and the weight block rotates centrifugally relative to the second axis to vibrate the brush.

Description

sway amplitude generated during the rotary vibration of the bush 122 (and the brush body 121) when driven by the weight block 133, so as to drive the brush to vibrate.

Note that allowance (an internal space) provided to the driven portion 122¢ of the bush 122 and a centrifugal effect of the weight block 133 may be appropriately adjusted relative to each other and are not further limited herein. For instance, if a designer tries to reduce vibration amplitude of the brush 120, the designer may expand the internal (lateral) space of the driven portion 122c, so as to lower a lateral force applied by the weight block 133 to the bush 122.

FIG. 5 is a schematic view of a transmission shaft and a weight block according to another embodiment of the disclosure. FIG. 6 is a local cross-sectional view of the transmission shaft and the weight block of FIG. 5 inside a brush. FIG. 7 is a schematic view illustrating rotation of the transmission shaft and the weight block of FIG. 5. With reference to FIG. 5 to FIG. 7 together, different from the foregoing embodiment, a transmission shaft 232 of this embodiment has a coaxial structure. That is, the first axis and the second axis described in the foregoing embodiment are parallel to and coincide with each other and are described as a fourth axis Z4 in this embodiment. Further, a weight block 233 of this embodiment is disposed along the fourth axis Z4 and is an asymmetrical structure. In other words, a center of gravity G of the weight block 233 (shown in FIG. 7) not being rotated is deviated from the fourth axis Z4. Accordingly, the transmission shaft 232 and the weight block 233 of this embodiment may deliver the same centrifugal rotation effect as described in the foregoing embodiment.

Herein, the weight block 233 forms a cutting structure 233a at a side thereof under a condition of which structural density of the weight block 233 is evenly distributed, such that the center of gravity of the weight block 233 is deviated. That is, a structural shape of the weight block 233 is a partially-cut cylindrical shape, and a cylindrical center axis (i.e., the fourth axis Z4) of the partially-cut cylindrical shape is located on an axis equivalent to the first axis Z1. Nevertheless, the disclosure is not limited thereto. In other embodiments that are not shown, a material of different density may also be adopted to form a symmetrical structure, such that the center of gravity of the weight block is also deviated. Note that except the transmission shaft 232 and the weight block 233, other structures in FIG. 6, including the bush 122, are identical to the structures shown in FIG. 3, and a relevant description thereof is thus omitted.

Further, a protruding portion 232a is further disposed on the transmission shaft 232 as shown in FIG. 5 and FIG. 6. In this way, when the weight block 233 and the transmission shaft 232 are assembled, a positioning (position-limiting) effect is achieved as a plane 232b on the protruding portion 232a and the cutting structure 233a are matched with each other.

As shown in FIG. 7, the dotted outline represents that the weight block 233 and the transmission shaft 232 are not yet rotated, and the solid outline represents that the weight block 233 and the transmission shaft 232 are rotated. As described above, an overall structure of the transmission shaft 232 of this embodiment extends along the fourth axis Z4, and the weight block 233 is coaxially disposed as the weight block 233 is also assembled to the transmission shaft 232. Nevertheless, the center of gravity G of the weight block 232 is deviated from the fourth axis Z4 through the cutting structure 233a. Hence, when the transmission shaft 232 drives the weight block 233 to rotate, centrifugal rotation is generated, and that the weight block 233 is deviated to a fifth axis Z5. As shown in FIG. 7, a third end

E4 is located on the fourth axis Z4, but a fourth end E4 is located on the fifth axis Z5 owing to centrifugal rotation. In this way, the transmission shaft 232 is bent at the multi-neck structure thereof, and the brush 120 is vibrated accordingly.

In view of the foregoing, in the electric toothbrush provided by an embodiment of the disclosure, the first end and the second end of the transmission shaft are respectively located ee r—————————— a — on the first axis and the second axis parallel to but different from each other. The first axis is connected to the power source, and the weight block is disposed on the second axis.

Hence, when the power source drives the transmission shaft, the first end self-rotates along the first axis, and the second end rotates around the first axis. Further, as the weight block is located on the second end, the weight block may thereby rotate centrifugally relative to the second axis.

That is, as the transmission shaft is constituted by the first segment located on the first axis and the second segment located on the second axis, so for the first axis, the second axis is laterally displaced relative to the first axis. Therefore, when the power source drives the first segment to rotate around the first axis, initial centrifugal rotation of the second segment of the transmission shaft is already completed. The weight block then rotates centrifugally relative to the second axis, so as to increase the vibration amplitude and effect.

In another embodiment, the transmission shaft has the coaxial structure (the structure thereof extends along the fourth axis Z4), and the weight block is coaxially assembled to the transmission shaft. Nevertheless, the center of gravity of the weight block is deviated through the cutting structure thereof. As such, when the transmission shaft drives the weight block to rotate, the weight block may rotate centrifugally as the center of gravity is deviated. In this way, the transmission shaft is bent, and the same brush vibration effect can be achieved.

Further, the brush is floatingly assembled to the body, the driven portion of the brush is sleeved on the weight block, and the transmission shaft is flexible. Therefore, the assembled brush may structurally limit the weight block to rotate back to the first axis, and the deformation of the transmission shaft and the centrifugal force generated during rotation may further act as the power to drive the brush to vibrate.

It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments.

It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims and their equivalents.

ELECTRIC TOOTHBRUSH

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan application no. 107111041, filed on March 29, 2018. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

TECHNICAL FIELD

The disclosure relates to an electric toothbrush.

BACKGROUND : :

Electric toothbrushes are new products that have emerged in recent years and caused a revolution in the field of oral health care. In an electric toothbrush, a brush vibrates or rotates through motor power, so that the toothpaste is decomposed into small bubbles to deeply clean the slits between the teeth. Comparing to general toothbrushes, the electric toothbrushes can more thoroughly remove dental plaque, reduce gingivitis, and avoid gum bleeding, and thereby, the electric toothbrushes become popular daily necessities.

Nevertheless, an excessively fast rotation speed of a brush may easily cause gum damage, and an excessively slow rotation speed of a brush may lead to insufficient cleaning.

Therefore, how a brush can be designed to deliver required vibration with simple components is an important issue in this field.

SUMMARY

The disclosure provides an electric toothbrush capable of delivering required vibration effect of a brush through a multi-axial and eccentric transmission shaft and a weight block disposed rr —————— Er ———__ y——,emi on an end portion of the transmission shaft to enable the weight block to rotate centrifugally when the transmission shaft rotates.

In an embodiment of the disclosure, an electric toothbrush includes a body, a brush, and a vibration assembly. The vibration assembly includes a power source, a transmission shaft, and a weight block. The power source is disposed in the body. The transmission shaft has a first end and a second end opposite to each other. The first end is connected to the power source and is located on a first axis together with the power source, and the second end extends outside the body. The weight block is disposed on the second end and is located on : a second axis together with the second end. The brush is movably assembled to the body and is sleeved on the weight block. When the power source drives the first end of the transmission shaft to rotate about the first axis, the second end rotates around the first axis, and the weight block rotates centrifugally relative to the second axis to drive the brush to vibrate.

To sum up, in the vibration assembly of the electric toothbrush, the first end and the second end of the transmission shaft are respectively located on the first axis and the second axis.

The first axis is connected to the power source, and the weight block is disposed on the second axis. Hence, when the power source drives the transmission shaft to rotate from the first end, the weight block located on the second end can generate the centrifugal force deviated from the transmission shaft on the second end along with rotation of the transmission shaft. The transmission shaft thereby rotates centrifugally on the second end and is bent, and the brush is vibrated accordingly, so as to increase the vibration amplitude and effect.

Several exemplary embodiments accompanied with figures are described in detail below to further describe the disclosure in details.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.

FIG. 1 is a schematic view of an electric toothbrush according to an embodiment of the disclosure.

FIG. 2A and FIG. 2B are exploded views of different parts of the electric toothbrush of FIG.

I.

FIG. 3 is a local cross-sectional view of the electric toothbrush of FIG. 1.

FIG. 4 is a schematic view of the transmission shaft and the weight block of the electric toothbrush of FIG. 1.

FIG. 5 is a schematic view of a transmission shaft and a weight block according to another embodiment of the disclosure.

FIG. 6 is a local cross-sectional view of the transmission shaft and the weight block of FIG. 5 inside a brush.

FIG. 7 is a schematic view illustrating rotation of the transmission shaft and the weight block of FIG. 5.

DETAILED DESCRIPTION

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.

————r——_— ———————————— PL — Ts

FIG. 1 is a schematic view of an electric toothbrush according to an embodiment of the disclosure. FIG. 2A and FIG. 2B are exploded views of different parts of the electric toothbrush of FIG. 1. With reference to FIG. 1, FIG. 2A, and FIG. 2B together, an electric toothbrush 100 includes a body 110, a brush 120, and a vibration assembly 130 in this embodiment. Among them, the vibration assembly 130 is assembled to the body 110, and the brush 120 is floatingly assembled to the body 110 and is sleeved on a portion of the vibration assembly 130 extending outside the body 110. Hence, the brush 120 may be driven to generate micro vibration relative to the body 110 through the vibration assembly 130.

FIG. 3 is a local cross-sectional view of the electric toothbrush of FIG. 1. With reference to

FIG. 2A, FIG. 2B, and FIG. 3, the body 110 of this embodiment is constituted by a component 111, a component 112, and a component 113. Among them, the component 111 and the component 112 are assembled with each other to form a handle of the electric toothbrush 100, and the component 113 is disposed in an accommodating space formed by the component 111 and the component 112. Note that the component 112 is omitted in the exploded view of FIG. 2A to better identify related members. Herein, the vibration assembly 130 includes a power source 131, a transmission shaft 132, and a weight block 133.

The power source 131 is, for example, a motor and is mounted in the component 113 of the body 110. The transmission shaft 132 has a first end E1 and a second end E2 opposite to each other. The first end El is connected to the power source 131, and the second end E2 extends outside the body 110 from inside the body 110 and is sleeved by the brush 120. The weight block 133 is disposed on the second end E2.

As shown in FIG. 2A, the transmission shaft 132 is a multi-axial structure, wherein the first end El is located on a first axis Z1, and the second end E2 is located on a second axis Z2.

Further, the first axis Z1 and the second axis Z2 are parallel to and different from each other.

ee ———————————— EE ——

Herein, the first axis Z1 and the second axis Z2 being different from each other means that the two axes do not coincide with each other. In other words, the power source 131 and the first end E1 of the transmission shaft 132 are together located on the first axis Z1, and the weight block 133 and the second end E2 of the transmission shaft 132 are together located on the second axis Z2. In this way, when the power source 131 drives the transmission shaft 132 to rotate, the first end El, the second end E2, and the weight block 133 may generate different rotation modes, and detailed description is provided below. i

In another aspect, with reference to FIG. 2A and FIG. 2B, the brush 120 includes a brush body 121 and a bush 122, and the body 110 further includes a buffer component 114 and a stop ring 115 in this embodiment. As shown in FIG. 2B and FIG. 3, the brush body 121 and a buckling portion 122b of the bush .122 are bucked to each other through a buckling portion 121a of the brush body 121, as such, a top portion of the bush 122 extends into the body 121.

At the same time, the stop ring 115 is held between the component 111 and a base portion of the bush 122. Further, as shown in FIG. 2A and FIG. 3, the buffer component 114 is disposed on the component 113, and the base portion of the bush 122 has protruding portions 122a to be inserted in inserting holes 114a of the buffer component 114. In this way, the bush 122 (and the brush body 121 buckled thereon) is substantially movably (floatingly) connected to the body 110. In other words, a movement dimension of the brush 120 (the brush body 121 and the bush 122) moving along the first axis Z1 is structurally limited by the body 110 according to such configuration, and that no relative movement is generated. But a movement dimension is generated on a plane on which the first axis Z1 acts as a normal line of the plane.

With reference to FIG. 3, the transmission shaft 132 is flexible and is further divided into a first segment Al and a second segment A2 herein in this embodiment. Among them, the first segment Al has the first end E1 connected to the power source 131, and the second ee ——————————————————— EE — Es. segment A2 has the second end E2 connected to the weight block 133. The first segment

Al extends along the first axis Z1, and the second segment A2 extends along the second axis 72. Note that when the bush 122 of the brush 120 is assembled to the buffer component 114 of the body 110 and is thus sleeved on the transmission shaft 132 and the weight block 133, the bush 122 further includes a driven portion 122¢ configured to accommodate an end portion of the weight block 133 and limit the end portion to rotate back to the first axis Z1, as shown in FIG. 3. Nevertheless, as the weight block 133 is substantially located on the second axis Z2 and is deviated from the first axis Z1, the bush 122 is movably assembled to the body 110. Accordingly, the transmission shaft 132 is deformed, and the end portion of the weight block 133 is thereby affected by an elastic force from the transmission shaft 132 to be leaned against the driven portion 122¢ of the bush 122. In this case, when rotating centrifugally, the weight block 133 may drive the brush 120 to generate rotary vibration about the first axis Z1 at any time.

Herein, the transmission shaft 132 is made of an elastic and flexible plastic material (e.g., polypropylene (PP)). Moreover, in the transmission shaft 132, a length of the first segment

Al is less than a length of the second segment A2. The second segment A2 has a multi-neck structure 132a, wherein an outer diameter of a neck portion is less than an outer diameter of the first segment Al (as shown in FIG. 3). In this way, flexibility of the second segment A2 of the transmission shaft 132 is increased, that is, a degree of yawing of the second segment A2 is increased when being rotated.

FIG. 4 is a schematic view of the transmission shaft and the weight block of the electric toothbrush of FIG. 1. With reference to FIG. 3 and FIG. 4 together, to be specific, FIG. 4 illustrates only movement modes of the transmission shaft 132 and the weight block 133, a condition of limiting the weight block 133 by the bush 122 is not yet added temporarily.

That is, the second end E2 (and the weight block 133) of the transmission shaft 132 is

LL ———————E————————— regarded as a free end. Accordingly, when the power source 131 drives the transmission shaft 132 to rotate, the first segment Al and the transmission shaft 132 of the power source 131 are together located on the first axis Z1. Hence, the first segment Al substantially performs in a movement mode of self-rotation (about the first axis Z1), and the second segment A2 performs lateral (as shown by an axis X in FIG. 4, referring to any lateral-related description in this embodiment) displacement relative to the first segment Al, as such, the second segment A2 substantially generates a movement mode to rotate around the first axis

Z1. That is, the second segment A2 may be regarded as the second axis Z2 and rotates around the first axis Z1 as shown in FIG. 4. Note that FIG. 4 is a schematic view of a movement and illustrates only a centrifugal tendency of a movement state and does not limit a degree of centrifugation, and thereby, the movement state is still required to be determined according to the flexibility of the transmission shaft 132 to generate corresponding degree of yawing. More importantly, since the weight block 133 is disposed on the second end E2, that is, the end where the second segment A2 is away from the first segment Al, the weight block 133 may rotate centrifugally when the second end A2 rotates. In other words, as shown in FIG. 4, the weight block 133 may be regarded as a (virtual) third axis Z3 rotating centrifugally relative to the first axis Z1 and has a centrifugal direction departing from the first axis Z1 and the second axis Z2.

With reference to FIG. 3, in the rotation mode when the weight block 133 is regarded as the free end, once the bush 122 is added, a movement interference is generated between the weight block 133 and the driven portion 122¢ of the bush 122. That is, the weight block 133 is structurally limited to rotate back to the first axis Z1 by the driven portion 122c.

Nevertheless, the bush 122 is still movable relative to the body 110, and thus, the centrifugal force (equivalent to a lateral displacement quantity of the third axis Z3 relative to the first axis Z1) generated when the weight block 133 is the free end can be converted into a lateral

Claims (12)

} er A ! _ ANT € CLAIMS oo - WHAT IS CLAIMED IS: oo ’ 3 =

1. An electric toothbrush, comprising: ’ . / & ¥ a body; ) © - a brush; | © a vibration assembly, assembled to the body, the vibration assembly comprising: = a power source, disposed in the body; = a transmission shaft, having a first end and a second end opposite to each other, 7 the first end being connected to the power source and located on a first axis together with the power source, the second end extending outside the body; and a weight block, disposed on the second end and located on a second axis together with the second end, the brush being movably assembled to the body and being sleeved on the weight block, and the brush being located on the first axis, the second end rotating around the first axis when the power source drives the first end of the transmission shaft to rotate about the first axis, the weight block rotating centrifugally relative to the second axis to vibrate the brush.

2. The electric toothbrush as claimed in claim 1, wherein the transmission shaft is flexible, the brush has a driven portion to accommodate an end portion of the weight block, and the brush limits the end portion of the weight block to rotate back to the first axis through the driven portion such that the end portion of the weight block is leaned against the driven portion and the brush is driven to generate rotary vibration along the first axis when the weight block rotates centrifugally.

3. The electric toothbrush as claimed in claim 1, wherein the brush comprises: a brush body; and a bush, the brush body being buckled to the bush along the first axis, the bush being inserted on a buffer component of the body along the first axis such that the bush is ¥ movable relative to the body. we

4. The electric toothbrush as claimed in claim 3, wherein the bush has a driven portion, and the weight block is accommodated at an end away from the transmission shaft © and is limited to the driven portion to limit a degree of centrifugation when the weight block - rotates centrifugally relative to the first axis. -

5. The electric toothbrush as claimed in claim 3, further comprising a stop ring, = the stop ring being held between a base portion of the bush and the body along the first axis, < the base portion of the bush having a protruding portion inserted in an inserting hole of the - buffer component.

6. The electric toothbrush as claimed in claim 1, wherein the first axis and the second axis are parallel to and different from each other.

7. The electric toothbrush as claimed in claim 6, wherein the transmission shaft is divided into a first segment and a second segment, the first segment extends along the first axis, the second segment extends along the second axis, the second segment rotates around the first axis when the first segment self-rotates along the first axis, the weight block rotates centrifugally relative to the first axis to drive the second segment to deviate from the second axis, and a centrifugal direction departs from the first axis and the second axis.

8. The electric toothbrush as claimed in claim 7, wherein a length of the first segment is less than a length of the second segment.

9. The electric toothbrush as claimed in claim 1, wherein the first axis and the second axis coincide with each other, and a center of gravity of the weight block is deviated from the first axis and the second axis such that the weight block drives the transmission shaft to deviate from the first axis and the second axis when the power source drives the transmission shaft to self-rotate along the first axis and the second axis.

10. The electric toothbrush as claimed in claim 9, wherein a structural shape of the > weight block is a partially-cut cylindrical shape. .

11. The electric toothbrush as claimed in claim 10, wherein a cylindrical center = ho axis of the partially-cut cylindrical shape is located on the first axis.

12. The electric toothbrush as claimed in claim 1, wherein the transmission shaft . has a multi-neck structure to increase flexibility of the transmission shaft. -