JP2010104718A - Actuator, and electric toothbrush using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide reciprocatory rotation of an electric toothbrush or the like without using a drive transmission mechanism as a separate member from a drive source. <P>SOLUTION: A fixed body 110 comprises a coil 160 disposed around a magnet 170 to face it at a specified interval respectively from magnetic pole surfaces 170a and 170b of different poles, and an outer yoke 150 covering the outer circumferential part of the coil 160. The fixed body 110 supports a movable body 120 comprising the magnet 170 through an elastic member 130 to be movable. An AC feed part 140 feeds AC of a similar frequency to the resonance frequency of the movable body 120, so that the movable body 120 makes reciprocatory rotation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an actuator used for an electric toothbrush or an electric sonic toothbrush.

  Conventionally, in electric toothbrushes including electric sonic toothbrushes, toothbrushes for bath polishing that vibrate left and right diagonally (about 45 degrees angle) at the boundary between teeth and gums by reciprocating linear motion, and a predetermined angle around the axis There is known a toothbrush for rolling brush that reciprocates (forward and reverse) in a range and moves so as to rotate from a gum toward a tooth.

  For driving these toothbrushes, a structure in which rotation of a rotary DC motor that rotates around a normal axis is linearly reciprocated or reciprocated via a motion direction conversion mechanism is often used. In addition to this structure, a structure in which the toothbrush is reciprocated linearly by a linear drive actuator, or a structure in which the toothbrush is reciprocally rotated by resonating a resonance vibration mechanism separate from the drive source by the vibration of the actuator is known. Yes.

  As shown in Patent Document 1, the structure in which the linear brush actuator reciprocates linearly the toothbrush directly generates a reciprocating vibration in the axial direction of the output shaft directly connected to the toothbrush portion, thereby realizing the bus polishing. Yes. In this structure, there is no power loss due to the motion conversion mechanism, and high-speed vibration can be performed.

Moreover, as shown in Patent Document 2, the structure having the actuator and the resonance vibration mechanism that is separate from the drive source excites the resonance vibration mechanism including the lever arm by the drive means including the electromagnet and the permanent magnet. Rolling polish is achieved by swinging the lever arm that is directly connected to the toothbrush and coaxial.
JP 2002-078310 A Japanese Patent No. 3243529

  By the way, in an electric toothbrush, while rolling rolling can be implement | achieved and it wants to make the part of the handle | strain in which the drive part which drives the toothbrush for rolling polishing accommodated as much as possible, size reduction of the drive part of a toothbrush is desired.

  However, in order to realize rolling polishing by using a motor that rotates around a normal axis, a motion direction conversion mechanism for converting the rotation of the motor into a reciprocating rotational motion is required in addition to the motor. Further, in order to realize rolling polishing using a linear drive actuator as in Patent Document 1, a torque generating mechanism (drive source) is required separately from the linear drive actuator.

  In the structure shown in Patent Document 2, a resonance vibration mechanism different from the drive source is required together with the drive source.

  Therefore, in the conventional structure, when a motor or a linear drive actuator is viewed as a drive source for an electric toothbrush, in addition to the drive source, there is a space for arranging a movement direction conversion mechanism, a torque generation mechanism, or a resonance vibration mechanism that is different from the drive source. Since it is necessary to ensure, there exists a problem that it is difficult to miniaturize a toothbrush.

  Furthermore, when a drive transmission mechanism such as a movement direction conversion mechanism separate from an actuator such as a motor is provided as a drive part of the toothbrush, the drive transmission mechanism may cause noise generation and efficiency deterioration due to generation of transmitted power loss. There is a fear, and it is necessary to consider these measures.

  The present invention has been made in view of the above points, and provides a miniaturized actuator and an electric toothbrush that can realize reciprocating rotational movement of an electric toothbrush or the like without using a drive transmission mechanism separate from a drive source. For the purpose.

  An actuator according to the present invention includes a movable body having a permanent magnet, a coil having an inner periphery that circulates around the permanent magnet and faces each other with a predetermined interval from a magnetic pole surface having a different pole in the permanent magnet, and an outer periphery of the coil A stationary body having an outer yoke that covers the portion, and movably supporting the movable body via an elastic support section; and an AC supply section that supplies an alternating current having a frequency substantially equal to the resonance frequency of the movable body to the coil. The structure provided with is taken.

  An electric toothbrush of the present invention includes an actuator having the above-described configuration, and a toothbrush including a bristle bundle portion that is connected to the output shaft of the actuator on the same axis as the output shaft, and is provided on the head perpendicular to the axial direction. The structure which has a part is taken.

  Since the reciprocating rotational motion of the electric toothbrush can be achieved without using a drive transmission mechanism that is separate from the drive source, a miniaturized actuator and electric toothbrush can be realized.

(Embodiment 1)
FIG. 1 is a perspective view showing an actuator 100 according to Embodiment 1 of the present invention, and FIG. 2 is an exploded perspective view of a main part of the actuator 100.

  The actuator 100 shown in FIGS. 1 and 2 includes a fixed body 110, a movable body 120, an elastic member (elastic support portion) 130 that movably supports the movable body 120 on the fixed body 110, and an AC supply unit 140. Have.

  In the actuator 100, a rotary reciprocating transmission shaft (an output shaft of the movable body 120 (see FIG. 2)) that is an output shaft of the movable body 120 (see FIG. 2) is obtained by the movement of the movable body 120 (see FIG. 2) movably supported by the fixed body 110 via the elastic member 130. Hereinafter, the “shaft” 125 rotates in the forward and reverse directions (in the direction of the arrow in FIG. 1) within a predetermined angle range, and outputs to the outside as rotational reciprocating vibration.

  As shown in FIG. 2, the fixed body 110 includes a base (base plate) 112, support wall portions 114 and 116, an outer yoke 150, and a coil 160 attached to the outer yoke 150. On the other hand, the movable body 120 includes a magnet (permanent magnet) 170, a magnet holding portion 124 that is supported by the support wall portions 114 and 116 via the elastic member 130 and holds the magnet 170, and shafts 125 and 126. Have.

  In the fixed body 110, the magnet 170 of the movable body 120 is arranged in the air gap inside the coil 160 in the outer yoke 150. In the actuator 100, the movable body 120 is driven in a resonance state when AC power (AC voltage) is input from the AC supply unit 140 to the coil 160.

  Specifically, in the fixed body 110, the base 112 has a long rectangular plate shape along the extending direction of the shaft 125 of the movable body 120, and is formed of a nonmagnetic material here.

  Above the surface of the base 112, the magnet 170 of the movable body 120 is disposed. The coil 160 circulates around the outer periphery of the magnet 160 and has an outer shape with a U-shaped cross section (including a U-shape). It arrange | positions in the state attached to the inner wall surface which the yoke 150 opposes.

  Further, support wall portions 114 and 116 are erected on the base 112 from end portions that are separated in the longitudinal direction.

  The support walls 114 and 116 have openings 114a and 116a through which the shafts 125 and 126 of the movable body 120 are inserted. The support walls 114 and 116 movably support the movable body 120 via the elastic member 130 in a state where the shafts 126 and 125 are rotatably inserted into the openings 114a and 116a, respectively.

  The support wall portions 114 and 116, together with the elastic member 130, hold the movable body 120 in a substantially horizontal direction (substantially parallel to the base 112) in a normal state. The shafts 125 and 126 may be inserted into the openings 114a and 116a in a state where there is play.

  The elastic member 130 supports the magnet 170 of the movable body 120 so as to be displaceable in the left-right and front-rear directions in a region facing the support wall portions 114 and 116.

  Here, the elastic member 130 is formed of a plate-like zigzag spring provided so as to protrude substantially horizontally at the upper end portion of the surface facing the support wall portions 114 and 116 in the facing direction. That is, the elastic member 130 is formed in a zigzag pattern by repeatedly extending a thin strip-shaped metal plate from one end portion toward the other end side in one width direction and folding back in the other width direction. As such, when one end and the other end are fixed, they can expand and contract in the torsional direction.

  In the elastic member 130 configured as described above, one end portion is attached by insert molding of the support wall portions 114 and 116, and the other end portion is attached to the magnet holding portion 124 that holds the magnet 170. As a result, the support wall portions 114 and 116 can move the movable body 120 in the torsion direction about the axes of the shafts 125 and 126 within the region surrounded by the base 112 and the outer yoke 150 via the elastic member 130. Support freely.

  FIG. 3 is a schematic cross-sectional view showing the main configuration of the actuator 100. In FIG. 3, as a magnetic circuit of the actuator 100, the flow of magnetic flux by the magnet 170 is indicated by a white arrow.

  Here, the outer yoke 150 has a substantially U-shaped cross section and is formed by bending a plate-like magnetic body. The outer yoke 150 includes a rectangular plate-shaped yoke central portion 151 and side wall portions 152 and 153 that are suspended from both side portions of the yoke central portion 151 and face each other.

  Here, the outer yoke 150 covers the magnet 170 and the magnet holding portion 124 of the movable body 120 by covering the base 112 and the support wall portions 114 and 116 from above. The outer yoke 150 is closed by the base 112 at the ends of the side wall portions 152 and 153, and forms a box that houses the movable body 120 together with the base 112 and the support wall portions 114 and 116.

  A coil 160 wound around the magnet 170 of the movable body 120 via an air gap is fixed to the inner wall surfaces 152a and 153a of the opposing side wall portions 152 and 153 of the outer yoke 150.

  Here, the coil 160 is a voice coil, and the outer diameter portion is fixed to the inner wall surfaces 152a, 153a of the both side walls 152, 153 of the outer yoke 150, and an air gap is formed from the inner peripheral portion inside the inner diameter. It arrange | positions so that the magnet 170 may be located through. That is, the inner peripheral portion of the coil 160 is opposed to the outer peripheral surface including the magnetic pole surfaces having different poles at a predetermined interval in the magnet 170.

  The coil 160 is coiled around an axis extending in a direction substantially perpendicular to the yoke central portion 151 and the base 112 of the outer yoke 150 and the shaft 125, between the side wall portions 152 and 153 of the outer yoke 150. Is formed into a rectangular tube shape.

  The coil 160 is attached to the yoke central portion 151 side on the inner wall surfaces of the side wall portions 152 and 153 of the outer yoke, and is disposed at a position facing the different magnetic poles (magnetic pole surfaces 170a and 170b) on the magnet 170.

  A magnet (permanent magnet) 170 disposed inside the coil 160 via an air gap is a rectangular parallelepiped having long magnetic pole surfaces 170 a and 170 b along the extending direction of the outer yoke 150. Here, the magnet 170 is rotatably held in an air gap inside the inner diameter of the coil 160 by a magnet holding portion 124 that is movably supported by the support wall portions 114 and 116 via the elastic member 130. Yes.

  2 and 3, the magnet holding portion 124 is formed in a U-shape when viewed from the side, and includes a rectangular plate-like bottom plate portion 124a on which the magnet 170 is placed, and a longitudinal direction (shaft) of the bottom plate portion 124a. 125, the front wall portion 124b and the rear wall portion 124c are erected at the end portions separated in the extending direction.

  Here, the magnet holding portion 124 is made of a non-magnetic material, and the shaft 125 is attached orthogonally to the front wall portion 124b, and the shaft 126 is coaxial with the shaft 125 on the rear wall portion 124c. It is attached so that it may be located on the top. That is, the shaft 125 is disposed along the approximate center of the magnet 170 substantially parallel to the different magnetic pole surfaces 170a and 170b (see FIG. 4) of the magnet 170.

  The magnet holding unit 124 holds the magnet 170 so as to be rotatable in the torsional direction about the shafts 125 and 126 while being spaced apart from the coil 160 and the back surface of the yoke central portion 151 of the outer yoke 150. In the movable body 120, the coil 160 is disposed between the front wall portion 124b of the magnet holding portion 124 and the magnet 170 and between the rear wall portion 124c and the magnet without being in contact with each other. It is movable outside.

  The magnetic pole surfaces 170a and 170b of the magnet 170 held by the magnet holding portion 124 are arranged so as to face the entire inner wall surface of the side wall portions 152 and 153 of the outer yoke via the coil 160.

  Here, the S pole side (S magnetic pole surface 170 a) of the magnet 170 is directed toward the inner wall surface 152 a side of the side wall portion 152 of the outer yoke 150, and the N pole (N magnetic pole surface 170 b) side is the side wall portion of the outer yoke 150. 153 is directed toward the inner wall surface 153a.

  As shown in FIGS. 1 and 2, the shaft 125 is provided so as to protrude outward from the support wall portion 116 in the same direction as the extending direction of the outer yoke 150. That is, the shaft 125 is provided in the actuator 100 so as to protrude in a direction substantially orthogonal to the direction in which the magnet 170 and the side wall portions 152 and 153 face each other with the coil 160 interposed therebetween.

  As described above, the shaft 125 is fixed to the front wall portion 124 b of the magnet holding portion 124, so that the shaft 125 is attached to the movable body 120 so as to be positioned on the axis passing through the center of gravity of the movable body 120. . As a result, the shaft 125 rotates and reciprocally vibrates together with the magnet 170 and the magnet holding portion 124 that constitute the main body of the movable body 120, and the vibration can be transmitted to the outside.

  In addition, when the actuator 100 is used for an electric toothbrush, the shaft 125 is connected to a toothbrush portion including a hair bundle portion provided on the head and orthogonal to the axial direction on the same axis as the shaft 125. As a result, the toothbrush portion performs the same movement as the shaft 125, in this case, rolling, which is rotational reciprocating vibration.

In actuator 100 of the present embodiment, the inertia J, when the torsion direction of the spring constant _{k sp,} movable body 120 of the movable member 120 with respect to fixed body 110, the resonance frequency is calculated by the following formula (1) Vibrate.

本実施の形態のアクチュエータ１００は、交流供給部１４０によって、コイル１６０に可動体１２０の共振周波数ｆ_０と略等しい周波数の交流を供給する。これにより、可動体１２０を効率良く駆動させることができる。

In the actuator 100 according to the present embodiment, the alternating current supply unit 140 supplies the coil 160 with alternating current having a frequency substantially equal to the resonance frequency f ₀ of the movable body 120. Thereby, the movable body 120 can be driven efficiently.

  As shown in FIG. 3, in the fixed body 110 and the movable body 120, the outer yoke 150, the magnet 170, and the coil 160 form a magnetic circuit.

  Specifically, in the actuator 100, a magnetic flux generated from the magnet 170 (indicated by a white arrow) is generated by an air gap between the coil 160, the side wall portion 153 of the outer yoke 150, the yoke center portion 151, the side wall portion 152, It has a magnetic circuit that passes through the air gap on the opposite side in order and reaches the counter electrode of the magnet 170.

The movable body 120 in the actuator 100 is supported by a spring mass structure supported by the fixed body 110 via an elastic member 130 (see FIGS. 1 and 2), and the resonance frequency f _{0 of the} movable body 120 is supported by the coil 160. When an alternating current having a frequency equal to is supplied, the movable body 120 is driven in a resonance state. The rotational reciprocating vibration generated at this time is transmitted to the shaft 125 of the movable body 120.

  The actuator 100 is driven based on the equation of motion represented by the following equation (2) and the circuit equation represented by the following equation (3).

すなわち、アクチュエータ１００における慣性モーメント、回転角度、トルク定数、電流、バネ定数、減衰係数、負荷トルクなどは、式（２）を満たす範囲内で適宜変更でき、電圧、抵抗、インダクタンス、逆起電力乗数は、式（３）を満たす範囲内で適宜変更できる。

That is, the moment of inertia, the rotation angle, the torque constant, the current, the spring constant, the damping coefficient, the load torque, etc. in the actuator 100 can be appropriately changed within the range satisfying the formula (2), and the voltage, resistance, inductance, counter electromotive force multiplier can be changed. Can be appropriately changed within a range satisfying the expression (3).

  Next, a specific operation of the actuator 100 will be described.

  FIG. 4 is a schematic diagram for explaining the operation of the actuator 100 according to the first embodiment. In FIG. 4A, the flow of magnetic flux by the magnet 170 is indicated by a white arrow, but is not shown in FIGS. 4B to 4D because it is the same flow. 4A illustrates an AC supply unit 140 that supplies an AC voltage to the coil 160, but FIGS. 4B to 4D illustrate the same as in FIG. 4A. Therefore, it is omitted.

  When alternating current is supplied to the coil 160 from the alternating current supply unit 140, thrusts indicated by arrows F 1, F 2, F 3, and F 4 in the figure due to electromagnetic force are generated in the coil 160 in accordance with Fleming's left-hand rule. As a result, the movable body 120 movably attached to the base 112 and the support wall portions 114 and 116 via the elastic member 130 generates a rotational force with the rotational center of gravity as the axis center.

  The operation for one cycle of the actuator 100 will be described.

  When a current flows through the coil 160 in the direction shown in FIG. 4A (this direction is referred to as a forward current), the facing portion 160b of the coil 160 facing the N pole surface 170b of the magnet 170 has a downward (base) The thrust F1 is generated in the direction 112). On the other hand, a thrust F2 is generated upward (in the direction toward the yoke central portion 151 of the outer yoke 150) in the portion 160a of the coil 160 facing the S pole surface 170a of the magnet 170.

  As a result, a rotating force is generated in the movable body 120 having the magnet 170 supported by the support wall portions 114 and 116 (see FIGS. 2 and 3) rising from the base 112 of the fixed body 110 via the elastic member 130. To do. In the movable body 120, thrusts R 1 and R 2 as reaction forces of the thrusts F 1 and F 2 of the coil 160 act on the magnet 170. As a result, the movable body 120 moves counterclockwise so as to be in the position shown in FIG.

  In the actuator 100 in the state shown in FIG. 4B, a force reaction force that returns the movable body 120 to the state in FIG. 4A is generated by the restoring force of the elastic member 130 (see FIGS. 2 and 3). From the state shown in FIG. 4B to the state shown in FIG. 4D, the coil 160 is supplied with a current in the direction opposite to that in FIG. Thereby, the movable body 120 has a thrust R3 as a reaction force of the restoring force of the elastic member 130 and the thrusts indicated by arrows F3 and F4 from the state of FIG. 4B to the state of FIG. 4C. R4 rotates clockwise with respect to the fixed body 110. Moreover, the movable body 120 rotates clockwise with respect to the fixed body 110 by the thrust shown by the arrows F3 and F4 acting on the magnet 170 from the state of FIG. 4C to the state of FIG. 4D.

  In the actuator 100 in the state shown in FIG. 4D, a force reaction force that returns the movable body 120 to the state in FIG. 4A is generated by the restoring force of the elastic member 130. A forward current is supplied to the coil 160 from the state shown in FIG. 4D through the state shown in FIG. 4A to the state shown in FIG. 4B. Thereby, the movable body 120 is the force of reaction between the restoring force of the elastic member 130 and the thrust indicated by arrows F1 and F2 from the state of FIG. 4D to the state of FIG. Rotate counterclockwise with respect to the fixed body 110 by the thrusts R1 and R2 acting on.

  Further, the movable body 120 rotates counterclockwise with respect to the fixed body 110 by the thrust indicated by the arrows R1 and R2 from the state of FIG. 4A to the state of FIG. 4B. The movable body 120 performs reciprocal rotational vibration around the substantially central axis of the magnet 170 extending inside the coil 160, but the thrusts R1 to R4 are mainly used without using the reaction force of the elastic member 130. Therefore, the same operation as that shown in FIG. 4 can be performed.

  Next, the alternating current supplied to the coil 160 of the movable body 120 in each state shown in FIG. 4 will be briefly described.

  FIG. 5 is a diagram showing the period of alternating current supplied from the alternating current supply unit 140 to the coil 160 of the movable body 120 in the actuator of the present embodiment.

The alternating current flowing through the coil may be a pulse wave with a frequency f ₀ as shown in FIG. 5A or a sine wave with a frequency f ₀ as shown in FIG. 5B.

  In the state of FIG. 4A, the forward current at the time point t1 shown in FIG. 5 is supplied, and in the state of FIG. 4B, the direction of the current is switched as shown at the time point t2 in FIG. In the state (c), a current in the reverse direction at time t3 shown in FIG. 5 is supplied. Further, in the state of FIG. 4D, the direction of current is switched as shown at time t4 in FIG. 5, and in the state of FIG. 4D, current in the forward direction at time t5 shown in FIG. 5 is supplied. The This is an operation for one cycle. By repeating such an operation, the movable body 120 oscillates in a reciprocating manner by repeating the displacement operation shown in FIGS. 4 (a) to 4 (d).

  In the actuator 100, the movable body 120 performs rotational reciprocating motion, that is, rotational reciprocating vibration, and this rotational reciprocating vibration is output to the outside via the shaft 125. When the toothbrush part provided with the hair | bristle bundle part provided in the head at right angles to the axial direction is connected to the shaft 125, a toothbrush part can carry out rolling polishing by reciprocating vibration.

  As described above, the actuator 100 satisfies the expressions (2) and (3) and is driven by the resonance phenomenon using the resonance frequency represented by the expression (1). Therefore, in the actuator 100, the power consumed in the steady state by the resonance drive is only the loss due to the load torque and the loss due to friction, etc., and the actuator 100 is driven with low power consumption. be able to. As described above, in the actuator 100 of the present embodiment, the reciprocating rotational movement of the electric toothbrush or the like can be realized without using a drive transmission mechanism separate from the drive source, and the size can be reduced. The reciprocating rotary motion can be realized with low power consumption.

  In addition, the movable body 120 is configured by the magnet 170 and the magnet holding portion 124 without including large components such as the outer yoke 150. For this reason, the magnitude of the moment of inertia of the movable body 120 can be determined depending on the shape of the magnet 170 without depending on the outer shape. Further, since the magnet 170 is disposed in the vicinity of the shaft 125 serving as the output shaft in the movable body 120, specifically, the center of gravity is positioned substantially on the axis of the shaft 125, the inertia of the movable body 120 is raised. It is hard to become a factor to let you. Therefore, since the increase in the moment of inertia in changing the outer shape of the actuator 100 is reduced, there is no design restriction, and the degree of freedom in designing the actuator 100 itself can be improved.

  The electric toothbrush having the actuator 100 can achieve the same effect as described above, and the electric toothbrush itself can be downsized.

  In the configuration of the actuator 100 according to the first embodiment, the base 112 has been described as a non-magnetic material. However, the configuration is not limited to this, and the magnetic material may be used. This configuration will be described with reference to FIG.

(Embodiment 2)
FIG. 6 is a schematic cross-sectional view showing the main configuration of the actuator according to Embodiment 2 of the present invention. In FIG. 6, as a magnetic circuit of the actuator 100, the flow of magnetic flux by the magnet 170 is indicated by a white arrow.

  An actuator 100A shown in FIG. 6 is obtained by replacing the non-magnetic base 112 with a magnetic base 112A in the configuration of the actuator 100. Therefore, the other configuration of the actuator 100A is the same as that of the actuator 100, and the same reference numerals are given, and the description thereof is omitted.

  The fixed body 110A of the actuator 100A includes a coil 160 disposed through an air gap so as to surround the magnet 170 of the movable body 120, and a magnetic member in which the outer peripheral portion of the coil 160 is fixed to the opposing inner wall surfaces 152a and 153a. The outer yoke 150 is a body and the base 112A is a magnetic body.

  That is, in the actuator 100A, the magnet 170 and the magnet holding portion 124 (only the bottom plate portion 124a is shown in FIG. 6) of the movable body 120 are surrounded by the outer yoke 150 and the base 112A that are magnetic bodies. The magnet 170 disposed inside the outer yoke 150 and the base 112 </ b> A and disposed inside the coil 160 has the magnetic pole surfaces 170 a and 170 b spaced apart from each other by a predetermined interval as in the configuration of the actuator 100. Are arranged in a direction intersecting with the circumferential direction of the outer yoke 150 and toward the side walls 152 and 153 of the outer yoke 150.

  With this configuration, in the actuator 100A, compared to the actuator 100, two magnetic flux paths are formed by the magnet 170 in the fixed body 110A.

  That is, in the magnetic circuit of the actuator 100A shown in FIG. 6, the magnetic flux generated by the magnet 170 (indicated by the white arrow) passes through the air gap where the coil 160 is disposed from the magnetic pole surface 170b, and the side wall portion of the outer yoke 150. 153. Next, the side wall portion 153 passes through the yoke central portion 151 and the base 112 </ b> A on the opposite side of the yoke central portion 151 to the side wall portion 152. Then, the magnetic flux sequentially passes through the air gap on the opposite side from the side wall portion 152 and is connected to the counter electrode (the magnetic pole surface 170a) of the magnet 170. Since the operation of the movable body 120 in the actuator 100A is the same as that of the actuator 100, the description thereof is omitted. FIG. 6 shows thrusts F1 and F2 of the coil 160 when a forward current is passed, and thrusts R1 and R2 of the magnet 170 which are reaction forces of these. When the thrusts R1 and R2 are generated, the movable body 120 moves in the direction of the thrusts R1 and R2. When the direction of the current is changed, a thrust reverse to F1 and F2 is applied to the coil 160, whereby a thrust reverse to R1 and R2 is applied to the magnet 170, and the movable body 120 is separated from R1 and R2. It moves in the direction indicated by the thrust in the reverse direction. By repeating these steps, the actuator 100A causes the movable body 120 to reciprocate and oscillate similarly to the first embodiment.

  As described above, in the actuator 100A of the second embodiment, the reciprocating rotational motion of the electric toothbrush or the like can be realized without using a drive transmission mechanism that is separate from the drive source. Can be obtained. Furthermore, according to the actuator 100A, by reducing the magnetic saturation in the magnetic circuit, it is possible to increase the thrust of the movable body 120 generated when the AC voltage is supplied to the coil 160 from the AC supply unit 140.

  Specifically, in actuator 100A, the torque for moving movable body 120 generated by coil 160 can be increased about 1.25 times as compared with the configuration of actuator 100 in the first embodiment.

  In the second embodiment, the outer periphery of the fixed body 110 that movably accommodates the movable body 120, that is, the magnetic circuit, is composed of the magnet 170 by the outer yoke 150 that is a magnetic body and the base 112A that is a magnetic body. It is configured as a circuit that surrounds.

  That is, since the outer surface of the actuator 100A is formed of a magnetic material, the leakage flux of the magnetic circuit including the base 112A, the outer yoke 150, the magnet 170, and the coil 160 can be suppressed in the actuator 100A.

(Embodiment 3)
The outline of the actuator according to the third embodiment is as follows. In the configuration of the actuator 100 (see FIGS. 2 and 3), the coil 160 is removed from the outer yoke 150 and a nonmagnetic material (spacer) is interposed on the base 112 side. A movable body 120 that is fixed and turned upside down is attached to the fixed body 110 via an elastic member 130 so as to be able to rotate and reciprocate in the torsional direction.

  FIG. 7 is an external view showing an actuator 100B according to Embodiment 3 of the present invention, FIG. 8 is an exploded perspective view of the actuator 100B, and FIG. 9 is a schematic diagram showing a main configuration of the actuator 100B. It is sectional drawing. The actuator 100B has the same basic configuration as that of the actuator 100 corresponding to the first embodiment shown in FIG. 1, and the same components are denoted by the same reference numerals and the description thereof is omitted. .

  The actuator 100B includes a fixed body 110B having an outer yoke 150, a base 112B, a coil 160, and support wall portions 114B and 116B, and an inner side (inner diameter portion) of the coil 160 via an air gap as shown in FIGS. A movable body 120B having a magnet 170, an elastic member 130 that supports the movable body 120B in a fixed body 110B, and a reciprocating rotation in a direction twisting around the shaft 125 of the movable body 120B, and an AC supply unit 140 ( 8 and 9).

  In the fixed body 110B, the base 112B has a base main body 1121 formed of a rectangular plate-like nonmagnetic material. Positioning projections 1122 and 1123 are provided on the surface of the base body 1121 so as to project upward and engage with recesses formed on the lower surfaces of the support wall portions 114B and 116B at the ends spaced apart in the longitudinal direction. Yes. The support wall portions 114B and 116B are attached to the base body 1121 so as to stand upright from the positions positioned on the base body 1121 through the positioning convex portions 1122 and 1123.

  An annular mounting groove 1124 is formed in the center portion of the surface of the base body 1121. The attachment groove portion 1124 is formed corresponding to the shape of the coil 160, has an inner diameter corresponding to the inner diameter of the cylindrical portion of the coil 160, and has a width slightly longer than the thickness of the cylindrical portion of the coil 160. It has become a groove. The coil 160 is attached so as to be positioned in the attachment groove 1124.

  An outer yoke 150 having a U-shaped cross section from above is supported on the base 112B and supports the surface of the base 112B with the side walls 152 and 153 in contact with the outer peripheral portion of the coil 160 on the base 112B. It is attached so as to cover the walls 114B and 116B.

  Inside the coil 160 provided on the base 112B, that is, on the inner diameter portion, a magnet 170 is disposed via an air gap.

  The magnet 170 is supported on the magnet holding portion 124 that is rotatably supported inside the coil 160 within the region surrounded by the outer yoke 150 and the base 112B via the elastic member 130 on the support wall portions 114B and 116B. Is retained.

  The magnet 170 is held by the magnet holding portion 124B at a position where the different magnetic pole surfaces 170a and 170b face the coil 160 via the air gap and are separated from the base 112B and the yoke central portion 151.

  The magnet holding portion 124B includes an upper surface portion 124d fixed to the upper surface of the magnet 170, and a front wall portion 124b and a rear wall portion 124c that are suspended from the longitudinal end portion (front and rear end portions) of the upper surface portion 124d. The magnet holding portion 124B is provided orthogonally to the front wall portion 124b and the rear wall portion 124c, and the shafts 125 and 126 arranged along the center of gravity of the magnet 170 are connected to the support wall portion of the fixed body 110B. 114B and 116B are inserted through openings 114a and 116a. The magnet holding part 124B is movably attached to the support wall parts 114B and 116B via the elastic member 130. Thereby, the magnet 170 and the magnet holding part 124 </ b> B are attached to the coil 160 positioned around the magnet 170 so as to be reciprocally rotatable in the torsion direction around the shafts 125 and 126. The elastic member 130 is attached to the support wall portions 114B and 116B as in the first embodiment. Specifically, the elastic member 130 is integrally attached to the inner lower side portion of each of the support wall portions 114B and 116B formed in the same manner as the support wall portions 114 and 116 by insert molding.

  In addition, like the actuator 100 of the first embodiment and the actuator 100A of the second embodiment, an alternating current having a frequency substantially equal to the oscillation frequency is input to the coil 160 by the alternating current supply unit 140 that supplies an alternating voltage. . As a result, the movable body 120B, which is supported on the fixed body 110B by the elastic member 130 so as to be movable in the torsional direction of the shaft 125, rotates and reciprocates due to the reaction force generated in the magnet 170 by the thrust of the coil 160 in the fixed body 110B. I do.

  FIG. 10 is a schematic diagram for explaining the operation of the actuator 100B according to the third embodiment of the present invention. In FIG. 10A, the flow of magnetic flux of the magnetic circuit by the magnet 170 is indicated by a white arrow. However, in FIG. 10B to FIG. Yes. 10A illustrates an AC supply unit 140 that supplies an AC voltage to the coil 160. In FIGS. 10B to 10D, the magnetic flux is supplied in the same manner as in FIG. 10A. Although there is a flow, it is omitted for convenience.

  As shown in FIG. 10A, the actuator 100B receives a magnetic flux (indicated by a white arrow) generated from the magnet 170 from the magnetic pole surface 170b, the air gap G, the coil 160, the side wall portion 153 of the outer yoke 150, A magnetic circuit that passes through the yoke central portion 151, the side wall portion 152, and the air gap on the opposite side in order is connected to the counter electrode (magnetic pole surface 170 a) of the magnet 170.

  In the actuator 100B, when alternating current is supplied to the coil 160 from the alternating current supply unit 140, the coil 160 generates thrusts indicated by arrows F1 to F4 in the figure in accordance with Fleming's left-hand rule. In response, the magnet 170 generates a rotational force (thrust R1 to R4) about the shaft 125, which is the rotational center of gravity, and the movable body 120 is the same as the movable body 120 of the actuator 100 shown in FIG. In addition, the operations shown in FIGS. 10A, 10B, 10C, and 10D are repeated to reciprocate and rotate.

  Thus, the actuator 100B has the same function and effect as the actuator 100. In addition, in the actuator 100B, the coil 160 is attached to the base 112B during assembly. That is, when assembling, in order to attach to the flat base 112B on the surface of the base 112B, the attaching operation is easily performed as compared with the case where the coil 160 is attached to the inner side of the U-shaped outer yoke 150. be able to.

  Here, since the coil 160 is attached so as to be positioned in the attachment groove portion 1124 formed on the surface of the base 112B, the coil 160 can be attached at the position positioned on the base 112B.

  Since the coil 160 itself is generally manufactured by winding a coil wire around a jig that defines the inner diameter of the coil, it is difficult to accurately manage the outer diameter of the coil 160 itself. Therefore, when the coil 160 is attached in the outer yoke 150, it is necessary to attach the coil 160 to the outer yoke 150 at the outer peripheral portion of the coil 160. Therefore, it is necessary to perform accurate management when the coil 160 is manufactured, which is troublesome.

  On the other hand, in the present embodiment, the position of the coil 160 is determined by the inner peripheral portion of the coil 160 by disposing the coil 160 directly in the mounting groove portion 1124 whose inner diameter is defined in the base 112B. be able to. Therefore, according to the actuator 100B, it is possible to improve assemblability and reduce man-hours.

  The actuator 100B is different from the actuator 100 mainly in the arrangement structure of the coil 160, but the magnetic circuit configuration is the same, and the same effects as the actuator 100 of the first embodiment can be obtained. In particular, according to the actuator 100B, reciprocating rotational movement of an electric toothbrush or the like can be realized without using a drive transmission mechanism that is separate from the drive source.

  In the actuator 100B, the base 112B is a non-magnetic material, but the base 112B may be a magnetic material. In this case, similarly to the second embodiment, the path of the magnetic flux in the fixed body 110B is a path from one side wall portion 153 of the outer yoke 150 to the other side wall portion 152 through each of the yoke center portion 151 and the base 112B. Thus, the same effect as in the second embodiment can be obtained.

(Embodiment 4)
FIG. 11 is a perspective view showing an actuator 100C according to Embodiment 4 of the present invention, and FIG. 12 is an exploded perspective view of a main part of the actuator 100C. The actuator 100C has a basic configuration similar to that of the actuator 100 corresponding to the first embodiment shown in FIG. 1, and the same components are denoted by the same reference numerals and the description thereof is omitted. .

  In the actuator 100C according to the fourth embodiment, in the actuator 100 shown in FIG. 1, the shafts 125 and 126 are rotatably supported by being inserted through the support wall portions 114 and 116 of the fixed body 110 via the bearings 190. The other configurations are the same.

  That is, in the actuator 100 </ b> C, as shown in FIGS. 11 and 12, the shaft 125 included in the movable body 120 is rotatably inserted into a bearing 190 attached to the opening 116 a of the support wall 116. The shaft 125 transmits and outputs a movable motion of the movable body 120 and functions as a shaft portion that pivotally supports the movable body 120 on the fixed body 110.

  In addition, the shaft 126 arranged on the same axis as the shaft 125 in the movable body 120 and protruding in the opposite direction to the shaft 125 is rotatably inserted into a bearing 190 attached to the opening 114 a of the support wall 114. Yes.

  For this reason, in the actuator 100C, when the alternating current is supplied to the coil 160 from the alternating current supply unit 140, the movable body 120 including the coil 160 rotates stably around the axis of the shaft 125 with respect to the fixed body 110. It will reciprocate.

  As described above, in the actuator 100C, the movable body 120 is pivotable with the shafts 125 and 126 inserted into the bearing 190 in a state where the support wall portions 114 and 116 have degrees of freedom in the rotational direction and the axial direction. It is supported. Further, the movable body 120 is supported by the support wall portions 114 and 116 via the elastic member 130 in a state in which movement in the axial direction is restricted. That is, the movable body 120 is attached to the fixed body 110 in a state in which the support wall portions 114 and 116 are secured to the support shafts 114 and 116 with the support shaft structure using the shafts 125 and 126 and the bearing 190 and the elastic member 130 in the rotational direction. It has a supported structure and is excellent in impact resistance.

  Therefore, in addition to the same effects as the actuator 100, the actuator 100C can stably rotate and reciprocate while fixing the rotation axis of the shafts 125 and 126, and improve the impact resistance of the actuator itself. be able to.

  In the present embodiment, the actuator 100C is configured such that the bearings 190 are provided on the support wall portions 114 and 116 in the actuator 100 according to the first embodiment, and the shafts 125 and 126 of the movable body 120 are rotatably supported. However, it is not limited to this. For example, the bearing wall 190 is provided on the support wall portions 114, 114B, 116, and 116B of the actuators 100A and 100B according to the second and third embodiments, and the shafts 125 and 126 of the movable body 120 are rotatably supported. It is good.

(Embodiment 5)
FIG. 13 is an exploded perspective view of an actuator 100D according to Embodiment 5 of the present invention, and FIG. 14 is a diagram showing an elastomer as a viscoelastic member used in the actuator 100D. 13 is a structure in which the structure of the elastic member 130 is changed in the actuator 100 corresponding to the first embodiment shown in FIGS. 1 to 4, and the other structures are the same. Therefore, the same components are denoted by the same reference numerals, and description thereof is omitted.

  In the actuator 100D, in the configuration of the actuator 100, instead of the elastic member 130 that is a zigzag spring, a viscoelastic body, in this case, an elastomer 197 having a large attenuation is used.

  As shown in FIG. 14, the elastomer 197 includes a central portion 197a having an insertion port 198 through which the shafts 125 and 126 are inserted, and an arm portion protruding from the central portion 197a in a direction perpendicular to the shafts 126 and the shaft 125. 197b. Since the elastomer 197 is a viscoelastic body, the central portion 197a and the arm portion 197b can be displaced by being elastically deformed from each other.

  The elastomer 197 is disposed between the support wall portions 116 and 114 and the front wall portion 124b and the rear wall portion 124c of the coil holding portion 124, and functions as a spring. The elastomer 197 has projections 114c, 116c, 124f formed on the support wall portions 116, 114 and the front and rear wall portions 124b, 124c in holes 198a, 198b formed at positions shifted in the extending direction of the arm portion 197b. 124g is inserted.

  Here, in the arm portion 197b of the elastomer 197, the protrusions 124f and 124g of the front and rear wall portions 124b and 124c are fitted into the hole portion 198a located near the center portion 197a by press fitting. Further, the protrusions 116c and 114c of the support wall portions 116 and 114 are fitted into the hole 198b farther from the center portion 197a by press fitting.

  According to the actuator 100D, the same effects as those of the actuator 100 can be obtained with the characteristics of the first embodiment. In the actuator 100D, the elastomer 197 is disposed between the support wall portions 116 and 114 and the front wall portion 124b and the rear wall portion 124c of the coil holding portion 124 so that the support wall portions 116 and 114 and the front wall portion 124b are disposed. In addition, the projections 114c, 116c, 124f, and 124g of the rear wall portion 124c are simply press-fitted into the holes 198a and 198b, so that they can be attached to both members (the support wall portion and the front and rear wall portions). Thus, unlike the case of using a metal spring such as a zigzag spring or a plate spring, the elastomer 197 can be attached to the movable body 120 and the fixed body 110 without requiring a complicated attachment process such as fastening with screws, adhesion, or insert molding. It can be made to function as a spring only by being sandwiched between them, and the assemblability of the actuator 100D itself can be improved.

  The elastomer 197 in the actuator 100D is configured to support the movable body 120 on the fixed body 110 so as to be movable in a torsional direction around the shafts 125 and 126 instead of the elastic member 130 in the actuators 100A and 100B. Also good.

  The present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

  The actuator according to the present invention has the effect of reducing the reciprocating rotational motion of an electric toothbrush and the like without using a drive transmission mechanism separate from the drive source, and vibrates and reciprocates for use in an electric toothbrush or the like. It is useful as an actuator.

The perspective view which shows the actuator which concerns on Embodiment 1 of this invention. The principal part disassembled perspective view of the actuator which concerns on Embodiment 1 of this invention. Schematic sectional view showing the main configuration of the actuator according to Embodiment 1 of the present invention. Schematic diagram for explaining the operation of the actuator according to the first embodiment of the present invention. The figure which shows the period of the alternating current supplied to a coil from the alternating current supply part in the actuator which concerns on Embodiment 1 of this invention. Schematic sectional view showing the main configuration of the actuator according to Embodiment 2 of the present invention. External view showing a configuration of an actuator according to Embodiment 3 of the present invention. The disassembled perspective view of the actuator which concerns on Embodiment 3 of this invention. Schematic sectional view showing the main configuration of the actuator according to Embodiment 3 of the present invention. Schematic diagram for explaining the operation of the actuator according to the third embodiment of the present invention. The perspective view which shows the actuator which concerns on Embodiment 4 of this invention. The principal part disassembled perspective view of the actuator which concerns on Embodiment 4 of this invention. The disassembled perspective view of the actuator which concerns on Embodiment 5 of this invention. The figure which shows the elastomer which is a viscoelastic member used for the actuator which concerns on Embodiment 5 of this invention.

Explanation of symbols

100, 100A, 100B, 100C, 100D Actuator 110, 110A, 110B Fixed body 112, 112A, 112B Base 114, 114B, 116, 116B Support wall 120, 120B Movable body 124, 124B Magnet holder 125, 126 Shaft 130 Elastic member 140 AC supply part 150 Outer yoke 151 Central part 152, 153 Side wall part 152a, 153a Inner wall surface 160 Coil 170 Magnet 170a, 170b Magnetic pole surface 190 Bearing 197 Elastomer 1124 Mounting groove part

Claims (10)

A movable body having a permanent magnet;
The permanent magnet has a coil having an inner peripheral portion facing each other with a predetermined interval from a magnetic pole surface having a different pole in the permanent magnet, and an outer yoke that covers the outer peripheral portion of the coil. A stationary body that movably supports the movable body,
An alternating current supply unit that supplies alternating current having a frequency substantially equal to the resonance frequency of the movable body to the coil;
Comprising
Actuator. The movable body includes an output shaft disposed along a substantially center of the permanent magnet substantially parallel to different magnetic pole surfaces of the permanent magnet, and is movable in a direction twisted around the output shaft by the elastic support portion. Supported by the
The actuator according to claim 1. The outer yoke has inner wall surfaces facing each other at a predetermined interval,
The coil is attached to each of the inner wall surfaces facing each other at the outer yoke at the outer periphery.
The actuator according to claim 1. The fixed body movably covers the movable body with a magnetic body including the outer yoke.
The actuator according to claim 1. The outer yoke has a U-shaped cross section that opens downward,
The fixed body has a plate-like base that is spaced apart below the movable body,
The coil is mounted on the base;
The outer yoke is attached to the base so as to cover the coil and the movable body in the coil.
The actuator according to claim 1. The base is made of a magnetic material.
The actuator according to claim 5. An attachment groove portion to which the coil is attached is formed on the surface of the base.
The actuator according to claim 5. The movable body is pivotally supported by the fixed body so as to be rotatable around the output shaft.
The actuator according to claim 2. The elastic support portion is a viscoelastic body that is interposed between the fixed body and the movable body and is deformable between the fixed body and the movable body.
The actuator according to claim 1. An actuator according to claim 2;
A toothbrush portion comprising a bristle bundle portion connected to the output shaft of the actuator on the same axis as the output shaft, and provided on the head perpendicular to the axial direction;
Having
electric toothbrush.

Images