Electric toothbrush and its design method

Abstract

This invention provides a method for designing an electric toothbrush that achieves a desired cleaning effect by optimizing the parameters of the elastic arm to efficiently vibrate the brush head. [Solution] The electric toothbrush includes a support frame, a drive frame, and a motor. The support frame has a hollow section, the drive frame is elastically connected to the support frame by an elastic arm, the drive frame is positioned in the hollow section and spaced apart from the support frame, and the upper end of the drive frame is provided with a mortise connection member for connecting the brush head. The motor is mounted on the drive frame, and a vibrating hammer is connected to the output shaft of the motor. The rotation of the motor drives the drive frame to swing or vibrate relative to the support frame, thereby driving the mortise connection member to swing or vibrate the brush head.

Description

[Technical Field]

[0001] This application belongs to the technical field of electric toothbrushes, and more particularly to electric toothbrushes and their design methods. [Background technology]

[0002] Conventional electric toothbrushes generally use an eccentric vibration motor to vibrate the brush head. The drive mechanism is bulky, structurally complex, and expensive. In addition, it produces a strong vibration sensation in the brush handle, is noisy, has significant damping of vibration output to the brush head, and consumes a lot of energy. [Overview of the Initiative]

[0003] The inventors have discovered that vibrations can be transmitted to the brush head via an elastically connected lever, but there is room for improvement in the design of the vibration frequency, amplitude, and force applied to the brush head.

[0004] This application aims to propose a design method for an electric toothbrush that achieves a desired cleaning effect by efficiently vibrating the brush head through the optimization of the parameters of the elastic arm.

[0005] Embodiments of this application propose a method for designing an electric toothbrush, wherein the electric toothbrush includes a support frame, a drive frame, and a motor, and the support frame is provided with a hollow section. The drive frame is elastically connected to the support frame by an elastic arm, positioned in the hollow section and spaced apart from the support frame, and the upper end of the drive frame is provided with a mortise connection member for connecting a brush head, the motor is mounted on the drive frame, and a vibration hammer is connected to the output shaft of the motor, and the rotation of the motor drives the drive frame to swing or vibrate relative to the support frame, thereby driving the mortise connection member to swing or vibrate the brush head. The effective length of the elastic arm is

[0006]

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[0007] In at least one possible embodiment, the centrifugal force F1 due to the vibrating hammer is as follows: F1=X(k-Mω 2 ) (In the formula, M represents the total mass of the tenon connecting member, the motor, the vibrating hammer, the drive frame, and the brush head connected to the tenon connecting member; X represents the amplitude of the brush head; and ω represents the rotational angular velocity of the motor.)

[0008] In at least one possible embodiment, the centrifugal force F1 due to the vibrating hammer is as follows: F1=meω 3 (In the formula, m represents the mass of the vibrating hammer, e represents the eccentricity of the vibrating hammer, and ω represents the rotational angular velocity of the motor.)

[0009] In at least one possible embodiment, the tenon connecting member is connected to a connecting portion, the tenon connecting member is connected to the elastic arm via the connecting portion, the connecting portion surrounds the tenon connecting member, the connecting portion is provided with a dynamic pivot point, the distance L1 from the dynamic pivot point to the end of the brush head is greater than the distance L2 from the dynamic pivot point to the vibrating hammer.

[0010] In at least one possible embodiment, if F1 is the centrifugal force produced by the vibrating hammer and F2 is the force output by the brush head, then L1 = L2 × (F2 / F1).

[0011] In at least one possible embodiment, the width of the cross-section of the elastic arm in the front-to-back direction of the electric toothbrush is greater than the height of the cross-section of the elastic arm in the left-to-right direction of the electric toothbrush.

[0012] In at least one possible embodiment, the flexural modulus of the elastic arm is 5000 MPa to 10000 MPa.

[0013] Embodiments of this application further propose an electric toothbrush, which is obtained by designing an electric toothbrush using the electric toothbrush design method described in any one of the above technical solutions.

[0014] In at least one possible embodiment, the drive frame and the support frame are connected by a connecting portion and an elastic arm, the connecting portion is connected to a tenon connecting member, the elastic arm is positioned on both the left and right sides of the connecting portion in the left-right direction of the electric toothbrush, and the elastic arm as a whole is a piece-shaped extension in the vertical and front-rear directions of the electric toothbrush.

[0015] In at least one possible embodiment, the tenon connecting member, the connecting portion, the elastic arm, and the support frame are integrally molded.

[0016] By adopting the above technical solution, the dimensions of the elastic arm can be rationally designed, the brush head can vibrate efficiently to achieve the desired motion characteristics, and a relatively good cleaning effect can be achieved. [Brief explanation of the drawing]

[0017] [Figure 1] This document shows an exploded perspective view of a partial structure of an electric toothbrush according to an embodiment of this application. [Figure 2] This shows a cross-sectional view of the brush handle of an electric toothbrush according to an embodiment of this application. [Figure 3] This shows a cross-sectional view of the brush handle of an electric toothbrush according to an embodiment of this application. [Figure 4]The front view of the support frame and the drive frame of the electric toothbrush according to the embodiment of the present application is shown.

Embodiments for Carrying Out the Invention

[0018] In order to more clearly explain the above objects, features, and advantages of the present application, in this part, specific embodiments of the present application will be described in detail in conjunction with the accompanying drawings. In addition to the embodiments described in this part, the present application can also be implemented in other different forms, and those skilled in the art can make corresponding improvements, modifications, and substitutions without departing from the spirit of the present application. Therefore, the present application is not limited by the specific examples disclosed in this part. The protection scope of the present application shall be subject to the claims.

[0019] In the following description, the vertical direction A of the electric toothbrush indicates the extending direction of the axis of the electric toothbrush, the upper side indicates the side where the brush head is arranged, and the lower side indicates the side where the brush handle is arranged. The front-rear direction F of the electric toothbrush indicates the extending direction of the bristles of the brush head of the electric toothbrush, the front side indicates the direction side of the bristles, and the rear side indicates the reverse side of the bristles. The left-right direction R of the electric toothbrush is perpendicular to both the vertical direction A and the front-rear direction F of the electric toothbrush.

[0020] As shown in FIGS. 1 to 4, the embodiment of the present application proposes an electric toothbrush including a brush handle and a brush head (not shown). The brush handle includes a main body 100, a support frame 1, a drive frame 2, a weight 3, a pressure-sensitive switch 4, a motor 5, a vibration damping member 6, and a shank 7. The support frame 1, the drive frame 2, the weight 3, the pressure-sensitive switch 4, the motor 5, and the vibration damping member 6 can be arranged inside the main body 100, and the shank 7 extends from the main body 100 to connect the brush head. The brush head is detachably and replaceably connected to the shank 7.

[0021] The support frame 1 can be used to attach or fix other components such as a battery 11 or a circuit board 12, and the support frame 1 can be provided with a hollow section 13, which can be positioned at an intermediate position in the left-right direction R of the electric toothbrush, and the hollow section 13 can pass through along the front-back direction F of the electric toothbrush.

[0022] The pressure-sensitive switch 4 can be connected to the circuit board 12 and is used to control the switch of the electric toothbrush. The pressure-sensitive switch 4 allows the user to conveniently control the on and off of the electric toothbrush, improving the user's ease of operation and user experience.

[0023] The drive frame 2 may include a motor chamber 22, and the motor 5 is housed in the motor chamber 22. A tenon connecting member 21 can be connected to the upper side of the drive frame 2, and in the vertical direction A of the electric toothbrush, the tenon connecting member 21 can be positioned above the motor chamber 22. The tenon connecting member 21 can be cylindrical, and the tenon connecting member 21 is fixedly connected to a tenon 7, which is used to connect the brush head. The tenon 7 can be made of metal.

[0024] A vibrating hammer 51 is connected to the output shaft of the motor 5. The vibrating hammer 51 can be cylindrical, and its axis is offset from the axis of the motor. When the motor 5 rotates the vibrating hammer 51, a centripetal force is generated, causing the drive frame 2 to oscillate or vibrate. Optionally, the distance (i.e., eccentricity e) between the axis of the vibrating hammer 51 and the axis of the motor can be 0.9 mm.

[0025] The drive frame 2 can be elastically connected to the support frame 1 by an elastic arm 24, and the drive frame 2 can be positioned in the hollow section 13, with the drive frame 2 as a whole being spaced apart from the support frame 1. The motor 5 (and vibrating hammer 51) can be connected to the drive frame 2, and the vibration of the motor 5 can drive the drive frame 2 to swing or vibrate relative to the support frame 1, and transmit that swing or vibration to the tenon connection member 21. By elastically connecting the drive frame 2 to the support frame 1 and spacing it apart as a whole, the brush head connected to the tenon 7 can be given a certain degree of freedom of movement, allowing the brush head to receive forces in different directions, which can more effectively clean teeth and massage gums.

[0026] Specifically, the drive frame 2 can be elastically connected to the support frame 1 by a tenon connecting member 21, a connecting part 25, and an elastic arm 24. The connecting part 25 can be connected to the tenon connecting member 21 and can be flat in shape, and the elastic arm 24 as a whole can be flat extending in the vertical direction A and the front-rear direction F of the electric toothbrush, and both ends of the elastic arm 24 can be curved to be connected to the connecting part 25 and the support frame 1, respectively. The connecting part 25 can surround the tenon connecting member 21. The tenon connecting member 21 is connected to the elastic arm 24 via the connecting part 25, and the connecting part 25 can be connected to the support frame 1 via two elastic arms 24, and the elastic arms 24 can be positioned on both the left and right sides in the left-right direction R of the connecting part 25. The dimensions of the connecting part 25 and the elastic arm 24 can be the same in the front-rear direction F. The connecting portion 25 and the elastic arm 24 can be formed in a U-shape, with the connecting portion 25 forming the bottom of the U, and the elastic arm 24 including two elastic pieces that form the two arm portions of the U. In the vertical direction A, the connecting portion 25 can be positioned at the lower end of the elastic arm 24. The elastic pieces can be in the shape of pieces extending along the vertical direction A and the front-rear direction F.

[0027] As can be understood, in other possible embodiments, the elastic arm 24 may be positioned on both the front and rear sides in the front-rear direction F of the connection portion 25.

[0028] A gap exists between the tenon connecting member 21 and the elastic arm 24, the tenon connecting member 21 is positioned between two elastic pieces, and the tenon connecting member 21 and the elastic pieces can be spaced 0.5 to 1 mm apart.

[0029] The elastic arms 24 can be provided on both the left and right sides of the connection portion 25 in the left-right direction R. The elastic arms 24 can be in the shape of a bendable piece, and the dimension (width b) in the front-rear direction F of the piece-shaped elastic arm 24 may be larger than the dimension (height h) in the left-right direction R, where the dimension (height h) in the left-right direction R of the piece-shaped elastic arm 24 does not include the distance between the two elastic arms 24, i.e., it refers to the thickness of the two elastic arms 24. As a result, the elastic arms 24 are easily bent and deformed along the left-right direction R of the electric toothbrush, but are difficult to bend and deform along the front-rear direction F of the electric toothbrush (although they are still deformable). As a result, the drive frame 2 can easily swing along the left-right direction R relative to the support frame 1, and drive the brush head to swing or vibrate along the left-right direction R to clean the teeth and / or gums.

[0030] As can be understood, the tenon 7, the tenon connecting member 21, and the drive frame 2 can be considered as a rigid rod, and by being connected to the support frame 1 by elastic arms 24, the rigid rod can be made into a lever. Two elastic arms 24 can be provided, and the two elastic arms 24 can be provided on opposite sides of the drive frame 2. The connection points between the two elastic arms 24 and the support frame 1 can be the fulcrums of the lever (first fixed fulcrum 27 and second fixed fulcrum 28). When the lever swings relative to the support frame 1, the positions of the first fixed fulcrum 27 and the second fixed fulcrum 28 are fixed relative to the support frame 1.

[0031] The tenon joint member 21 may have a dynamic pivot point 29, which, as can be understood, is an artificially defined virtual position and not a structurally existing support point. When the motor 5 drives the lever and swings relative to the support frame 1, the position of the dynamic pivot point 29 moves relative to the support frame 1.

[0032] The vibration system, consisting of a support frame 1, a drive frame 2, a tenon connecting member 21, a connecting part 25, a tenon 7, a brush head, and an elastic arm 2, can be simplified and considered as a vibration system with one degree of freedom. The drive frame 2, tenon connecting member 21, connecting part 25, tenon 7, brush head, motor, vibration hammer, etc., are equivalent as levers with a concentrated mass M (approximately 2g in this application), the two elastic arms 24 can provide spring characteristics, the two elastic arms 24 have equivalent stiffness k, and the vibration hammer 51 driven by the motor can provide an excitation force F(t), which is a time-varying external excitation force acting on the vibration system with one degree of freedom. The bending modulus of the elastic arm 24 can be 5000MPa to 10000MPa.

[0033] A vibration system with one degree of freedom can be described by a spring-mass-damping system model.

[0034]

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[0035]

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[0036]

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[0037] The amplitude X of the brush head can be estimated using a simplified formula for the spring-mass-damping system, and the amplitude X can be expressed by the following equation.

[0038]

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[0039]

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[0040] Let F1 be the centrifugal force produced by the vibrating hammer 51, and F2 be the force output by the brush head. F1=meω 3 =X(k-Mω 2 ). The equivalent stiffness of the elastic arm is,

[0041]

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[0042] For example, when m = 0.75 g and e = 0.9 mm, F1 = 2.396 N.

[0043] The moment of inertia of the cross-section of the elastic arm is

[0044]

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[0045] b represents the cross-sectional width of the elastic arm (dimension in the front-rear direction F), and h represents the cross-sectional height of the elastic arm (dimension in the left-right direction R). The cross-sectional width b and the cross-sectional height h of the elastic arm are different in that the cross-sectional width b of the elastic arm is larger than the cross-sectional height h of the elastic arm. In this embodiment, when b = 9.5 mm and h = 1.4 mm, the moment of inertia I of the cross-section of the elastic arm is 2.17×10 -12 and the flexural modulus of elasticity of the elastic arm can be 9.6×10 9 Pa (that is, 9600 MPa). Thereby, the elastic arm 24 can drive the hozo connection member 21 to perform elliptical vibration, and further drive the brush head to perform high-frequency cleaning movement.

[0046]

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[0047]

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[0048] By making L1 greater than L2, and by setting L1 to the distance from the dynamic pivot point 29 to the end of the brush head, and L2 to the distance from the dynamic pivot point 29 to the vibrating hammer 51, the electric toothbrush can be made more compact.

[0049] Specifically, L1 = L2 × (F2 / F1). For example, if F2 is set to 0.64N as needed for cleaning, and L2 is set to 80mm according to the dimensions of the brush head, then L1 can be calculated as 21.5mm.

[0050] As can be understood, the cross-sectional area of ​​the elastic arm 24 affects the second moment of area I of the elastic arm 24. When the second moment of area I increases, the rigidity of the elastic arm 24 increases, so the amplitude of the brush head (tenon 7) decreases, making it suitable for fine and careful cleaning. When the second moment of area I decreases, the rigidity of the elastic arm 24 decreases, so the amplitude of the brush head (tenon 7) increases, making it suitable for powerful cleaning.

[0051] Increasing the effective length Ls of the elastic arm 24 reduces the rigidity of the elastic arm 24, resulting in a larger amplitude of the brush head (tenon 7), making it suitable for powerful cleaning. Shortening the effective length Ls of the elastic arm 24 increases the rigidity of the elastic arm 24, resulting in a smaller amplitude of the brush head (tenon 7), making it suitable for fine and careful cleaning.

[0052] In other words, the dimensions of the elastic arm 24 directly affect the amplitude of the brush head (tenon 7), and this application allows for the calculation of the effective length Ls of the elastic arm 24 when the cross-sectional area of ​​the elastic arm 24 is known, and also allows for the calculation of the cross-sectional area of ​​the elastic arm 24 when the effective length Ls of the elastic arm 24 is known, as required by actual needs.

[0053] In this embodiment, the tenon connecting member 21, the elastic arm 24, the connecting portion 25, and the support frame 1 can be integrally molded as selectable, thereby increasing the overall structural strength and stability of the support frame 1 and the drive frame 2.

[0054] Optionally, the drive frame 2 can be provided with a weight chamber 23, which can be positioned above the motor chamber 22, and the weight 3 can be housed in the weight chamber 23. In the vertical direction A of the electric toothbrush, the vibrating hammer 51 can be positioned below the motor 5, and the weight 3 can be positioned above the motor 5. The weight 3 increases the overall weight of the drive frame 2, balances the vibrations generated when the motor is operating, avoids imbalances caused by vibration, maintains stability during use of the electric toothbrush, and allows the brush head to move more smoothly and efficiently.

[0055] For example, two waterproof ring mounting holes 15 can be provided at the upper end of the support frame 1, and the two waterproof ring mounting holes 15 can be provided on both the left and right sides of the tenon connecting member 21 in the left-right direction R of the electric toothbrush. The waterproof ring mounting holes 15 can be used to connect a waterproof ring 14. The waterproof ring 14 is used to prevent water and bubbles from entering the inside of the main body 100.

[0056] The vibration damping member 6 can be connected to the drive frame 2, and at least a portion of the vibration damping member 6 is placed in the gap between the drive frame 2 and the support frame 1. The vibration damping member 6 is elastic, and for example, it can be made of rubber. When the drive frame oscillates or vibrates, the vibration damping member 6 can effectively absorb and mitigate the vibrations transmitted to the support frame 1, reducing the intensity of vibrations transmitted to the user's hand and improving comfort during use. For example, the vibration damping member 6 can be attached to the drive frame 2 along the front-rear direction F, and the dimension of the vibration damping member 6 in the left-right direction R can be made larger than the dimension of the drive frame 2 in the left-right direction R, so that a portion of the vibration damping member 6 is placed in the gap between the drive frame 2 and the support frame 1.

[0057] By damping vibrations with the vibration damping member 6, the motor 5 and other components can be protected, and the noise generated when the motor 5 is operating can be reduced, resulting in a quieter electric toothbrush experience and improved user experience. Furthermore, since the vibration damping member 6 can also dampen external impacts, damage from falls is reduced, extending the lifespan of the electric toothbrush.

[0058] Furthermore, the drive frame 2 can be provided with a vibration damping member mounting groove 26, and the vibration damping member 6 can be attached to the vibration damping member mounting groove 26. In the vertical direction A of the electric toothbrush, the vibration damping member mounting groove 26 can be provided on the lower side of the motor chamber 22, and the vibration damping member 6 can be provided on the lower side of the motor 5.

[0059] When using the electric toothbrush of this application, the user can turn on the electric toothbrush with the pressure-sensitive switch 4 to activate the power, thereby rotating the motor 5. The motor 5 drives the vibrating hammer 51 to rotate, causing the drive frame 2 to oscillate or vibrate around its pivot point, transmitting power to the tenon connecting member 21, and allowing the brush head to oscillate or vibrate in multiple directions via the tenon 7. Since the drive frame 2 and the brush head are located at both ends of the pivot point, the principle of leverage is used to amplify the oscillation or vibration of the drive frame 2 at the position of the bristles of the brush head. This oscillation or vibration effectively cleans the tooth surface and hard-to-reach areas, improving the effectiveness of toothbrushing.

[0060] It should be understood that at least some aspects or features in the above embodiments, examples, or illustrations can be suitably combined.

[0061] To the extent that it can be understood, in this application, if the number of members or parts is not particularly limited, the number may be one or more, where more means two or more. Where the number of members or parts is illustrated in the accompanying drawings and / or described in the specification as a specific number such as two, three, or four, such specific number is generally illustrative and not limiting, and can be understood as more than one, i.e., two or more, but this does not mean that this application excludes the case of one.

[0062] In this application, unless otherwise clearly stated or limited, terms such as “mounting,” “assembly,” “joining,” “connection,” “coupling,” “linking,” “contact,” “communication,” “interconnection,” “conductivity,” “fixing,” and “tightening” should be understood in a broad sense, and may be direct or indirect, for example. For example, with respect to connection, it may be a fixed connection, a detachable connection, or a connection formed integrally; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection via an intermediate medium; and unless otherwise clearly stated or limited, it may be a connection within two elements or an interaction relationship between two elements. For example, with respect to communication / conductivity, it may be direct communication / conductivity or indirect communication / conductivity via an intermediate medium. A person skilled in the art will be able to understand the specific meaning of the above terms in this application depending on the specific situation.

[0063] In this application, unless otherwise clearly stated or limited, the placement / mounting / location / housing / situation of one component within, inside, or within another component may be in any one of the following two forms: that a portion or most of the one component is located within the other component, and that the one component is completely housed within the other component.

[0064] Although this application has been described in detail using the embodiments described above, it will be apparent to those skilled in the art that this application is not limited to the embodiments described herein. This application can be implemented in modified and altered embodiments without departing from the essence and scope of this application as defined by the claims. Accordingly, the descriptions herein are for illustrative purposes only and are not intended to be restrictive in any way to this application. [Explanation of symbols]

[0065] 1. Support frame 11 Batteries 12 Circuit boards 13 Hollow part 14 Waterproof Rings 15 Waterproof ring mounting holes 2 Drive frame 21. Mortise and tenon joint member 22 Motor Room 23 Weight Room 24 Elastic Arms 25 Connection part 26 Vibration damping member mounting groove 27 First fixed support point 28 Second fixed support point 29 Dynamic fulcrum 3 weights 4. Pressure-sensitive switch 5 Motors 51 Vibration Hammer 6. Vibration damping members 7 mortise A Vertical direction F Front and back direction R Left / right direction

Claims

1. A method for designing an electric toothbrush, wherein the electric toothbrush includes a support frame (1), a drive frame (2), and a motor (5), and the support frame (1) is provided with a hollow portion (13). The drive frame (2) is elastically connected to the support frame (1) by an elastic arm (24), positioned in the hollow portion (13), and spaced apart from the support frame (1). The upper end of the drive frame (2) is provided with a tenon connecting member (21) for connecting a brush head. The motor (5) is mounted on the drive frame (2), and a vibration hammer (51) is connected to the output shaft of the motor (5). The rotation of the motor (5) drives the drive frame (2) to swing or vibrate relative to the support frame, thereby driving the tenon connecting member (21) to swing or vibrate the brush head. The effective length of the elastic arm (24) is [Math 1] A method for designing an electric toothbrush, characterized by the following: (In the formula, E represents the flexural modulus of the elastic arm (24), b represents the cross-sectional width of the elastic arm (24), h represents the cross-sectional height of the elastic arm (24), and k represents the total stiffness coefficient of the elastic arm (24).)

2. The centrifugal force generated by the vibrating hammer (51) is F １ A method for designing an electric toothbrush according to claim 1, characterized in that... F １ =X(k-Mω ２ ) (In the formula, M represents the total mass of the tenon connecting member (21), the motor (5), the vibrating hammer (51), the drive frame (2), and the brush head connected to the tenon connecting member (21); X represents the amplitude of the brush head; and ω represents the rotational angular velocity of the motor.)

3. The centrifugal force generated by the vibrating hammer (51) is F １ A method for designing an electric toothbrush according to claim 1, characterized in that... F １ =meω ３ (In the formula, m represents the mass of the vibrating hammer (51), e represents the eccentricity of the vibrating hammer (51), and ω represents the rotational angular velocity of the motor (5).)

4. The tenon connecting member (21) is connected to a connecting portion (25), the tenon connecting member (21) is connected to the elastic arm (24) via the connecting portion (25), the connecting portion (25) surrounds the tenon connecting member (21), the connecting portion (25) is provided with a dynamic pivot point (29), and the distance L from the dynamic pivot point (29) to the end of the brush head １ The distance L from the dynamic pivot point (29) to the vibrating hammer is the distance L. ２ A method for designing an electric toothbrush according to claim 1, characterized in that it is larger than [a certain value].

5. The centrifugal force by the vibration hammer (51) is F １ and the force output by the brush head is F ２ and L １ = L ２ × (F ２ / F １ ), characterized in that it is the design method of the electric toothbrush according to claim 4

6. The method for designing an electric toothbrush according to claim 1, characterized in that the width of the cross-section of the elastic arm (24) in the front-to-back direction (F) of the electric toothbrush is greater than the height of the cross-section of the elastic arm (24) in the left-to-right direction (R) of the electric toothbrush.

7. The method for designing an electric toothbrush according to claim 1, characterized in that the bending modulus of the elastic arm (24) is 5,000 MPa to 10,000 MPa.

8. An electric toothbrush characterized by being obtained by designing using the electric toothbrush design method described in any one of claims 1 to 7.

9. The electric toothbrush according to claim 8, wherein the drive frame (2) and the support frame (1) are connected by a connecting portion (25) and an elastic arm (24), the connecting portion (25) is connected to the tenon connecting member (21), the elastic arm (24) is positioned on both the left and right sides of the connecting portion (25) in the left-right direction (R) of the electric toothbrush, and the elastic arm (24) as a whole is a piece-shaped extension in the up-down direction (A) and the front-back direction (F) of the electric toothbrush.

10. The electric toothbrush according to claim 9, characterized in that the tenon connecting member (21), the connecting portion (25), the elastic arm (24), and the support frame (1) are integrally molded.

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