JP3121971U - Magnetic levitation actuator motor - Google Patents

Abstract

A magnetic levitation actuator motor is provided.
A magnetic levitation actuator motor is provided with a magnetic element and an excitation actuator on a table, the center of the table is hollowed out, and a coil is wound around the outside. It can be freely moved up and down. Since the excitation actuator has a characteristic of maintaining the magnetic field strength for a certain time after the excitation, the coil generates a magnetic flux by energization, magnetizes the actuator, generates a magnetic field strength, and operates by attracting or repelling the magnetic element. Even after the current is cut off, the balance point is still maintained. Thus, electricity can be supplied intermittently to save power, and the structure is simple and the assembly cost is low.
[Selection] Figure 2

Description

  The present invention relates to a type of magnetic levitation actuator motor, in particular, a type of excitation element, which is related to the structure of the motor actuator shaft, and has the features of power saving, fewer parts, and simple structure.

  Small consumer products such as mobile phones and digital cameras use small voice coil motors (VCMs) as short-distance actuator motors. Since it has advantages such as compactness and low cost, it is suitable for an actuator that moves the magnetic head / optical read / write head up and down, an auto focus actuator for a camera, a zoom actuator for a camera lens, and the like.

  FIG. 1 is a side view sectional view of a voice coil motor (VCM) for automatic focusing of a known camera. An operation unit 110 is provided at the axial center of a known voice coil motor 100, a lens 95 is mounted, a coil 115 is wound around the outer periphery of the operation unit 110, and a magnet 120 is provided outside the voice coil motor 100. The coil 115 of the axially operating portion 110 generates a magnetic field polarity after energization, and realizes the effect of moving the operating portion 110 up and down by repulsion or attraction to the magnet 120 provided outside.

  Furthermore, the working distance of the working part can be controlled by the magnitude of the current flowing through the coil. However, since there are many assembly parts and the assembly cost is high, since the operation of the voice coil motor relies on the coil, power consumption is large. This is a difficult problem to overcome for small devices such as cameras and mobile phones.

  As a result of earnest research and repeated improvement of the known voice coil motor, the present inventor devised a kind of novel magnetic levitation actuator motor. A place where the excitation element and the magnet provided outside are balanced at a certain time by using an excitation element for the motor operating part, generating a magnetic field in the excitation element by energization by energization, and then interrupting the power supply Therefore, the purpose of power saving and simple structure can be realized.

  In order to achieve the above object, the magnetic levitation actuator of the present invention is mainly composed of a table, one or more magnetic elements, and an excitation actuator. The base has a cylindrical shape with a hollowed center, and a coil is wound around the outer periphery. The magnetic element is provided in the opening of the free end of the central portion of the table, and the excitation actuator is provided in the hollow space of the central portion of the table so that it can freely move up and down. The characteristics of the excitation actuator material can maintain the magnetic field strength for a certain time after excitation. Therefore, when the coil is energized, it generates magnetic flux and excites the excitation actuator, generates magnetic field strength, and operates by attracting or repelling the magnetic element. Even after the power is turned off, the magnetic field strength is maintained for a certain time that can achieve the purpose of power saving and simple structure because it is maintained in a balanced place for a certain time. As a result, electricity can be supplied intermittently to save power, as well as to simplify the structure and reduce assembly costs.

The invention of claim 1 includes a platform, one or more magnetic elements and an excitation actuator,
The base is hollowed out in the center and coiled around the outside.
One or more magnetic elements are provided in the free end opening in the central cutout space of the table,
An excitation actuator using an excitation material is provided in a hollow space in the center of the base and can move up and down. Its characteristics are that the magnetic field strength is maintained at a certain time after excitation, and magnetic flux is generated by energizing the coil. An exciting actuator is a type of magnetic levitation that is excited, generates magnetic field strength, operates by attracting or repelling magnetic elements, and can maintain a balanced place at a certain time even after the power is turned off Actuator motor.
The invention of claim 2 is the magnetic levitation actuator motor according to claim 1, wherein the pedestal is a magnetic levitation actuator motor characterized by a cylindrical shape.
According to a third aspect of the present invention, there is provided the magnetic levitation actuator motor according to the first aspect, wherein two magnetic elements are provided in the upper and lower end openings of the central portion of the base. Yes.
According to a fourth aspect of the present invention, there is provided the magnetic levitation actuator motor according to the first aspect, wherein a thread for screwing a lens into the excitation actuator is provided.
The invention according to claim 5 is the magnetic levitation actuator motor according to claim 1, wherein the magnetic element is a magnet.
The invention of claim 6 is the magnetic levitation actuator motor according to claim 1, wherein the magnetic element is an electric magnet.
According to a seventh aspect of the present invention, in the magnetically levitated actuator motor according to the first aspect, one or more guide grooves are provided in the central part cut-out space of the base, the guide rods are provided on the excitation actuator, The magnetic levitation actuator motor is characterized in that it is slid up and down to guide the moving direction of the excitation actuator.
The invention according to claim 8 is the magnetically levitated actuator motor according to claim 1, wherein the magnetic field strength of the excitation actuator is demagnetized over time, so that when the excitation actuator is maintained at a certain position for a long time, the current is intermittent. The magnetic levitation actuator motor is characterized in that it is supplied and excited.
The invention of claim 9 is the magnetically levitated actuator motor according to claim 1, wherein the equation of control of a balanced place can be maintained by the operation of the excitation actuator and the magnetic element, and the excitation actuator has a magnetic field when the current is cut off. The function m (t) of strength (m) and time (t) is set to D (d (m (t)) / dt), respectively, by the external magnetic field strength Decay.
If the allowable displacement of the excitation actuator is
D _optical = D (d (m (t)) / dtI t = T _holding ), where T _holding indicates the time during which no current is required,
If the operating position of the excitation actuator is FN (m) from the balance location, m, m1, and m2 indicate the magnetic field strength of the excitation actuator, the upper magnet, and the lower magnet, and are calculated from the following equations.
F _N (m) = F _S (m) + W _C ,
→ (μ _o / 4π) × (m × m ₁ / (h−L−Z) ² ) = (μ _o / 4π) × (m × m ₂ / Z ² ) + W _c ,

→ Z≡Z (m (t)),
→ D≡D (d (m (t)) / dt),
The magnetic levitation actuator motor is characterized by this.

  A type of magnetic levitation actuator motor, which is provided with a magnetic element and an excitation actuator on the base, hollowed out at the center of the base, wound around the coil, and attached to the opening at the free end of the central part of the base. It can be moved up and down. Since the excitation actuator has a characteristic of maintaining the magnetic field strength for a certain time after excitation, the coil generates a magnetic flux by energization, magnetizes the actuator, generates a magnetic field strength, and operates by attracting or repelling the magnetic element. Even after the current is cut off, the balance point is still maintained. Thus, electricity can be supplied intermittently to save power, and the structure is simple and the assembly cost is low.

  2 is an elevational view of the present invention, and FIG. 3 is an exploded view of the present invention. The magnetically levitated actuator motor 10 of the present invention is mainly provided with a cylindrical base 11 hollowed out at the center, wound around a coil 12 around the outer periphery thereof, and provided with an excitation actuator 13 in the hollowed space at the center of the base 11 so as to freely move up and down. Make it possible. The actuator 13 uses a material such as a plastic magnet and has excitation characteristics. An exciting member is placed in a magnetic field, and a magnetic field is generated by excitation. However, it is not permanently excited, but demagnetized after a certain period of time.

  The excitation actuator 13 is also provided with a cylindrical shape, provided with a female thread on the inner peripheral surface, and screwed with a load member such as a camera lens. A magnetic element 14 such as a magnet or an electric magnet is provided in the upper and lower openings of the table 11, and the magnetic element 14 is annular and has a central portion that is similar in diameter to the excitation actuator 13.

  One or more guide grooves 111 are provided on the inner peripheral surface of the central portion of the base 11, and the guide rod 131 is provided so as to protrude on the excitation actuator 13. The guide rod 131 is accommodated in the guide groove 111 and slides freely up and down to guide the moving direction of the excitation actuator 13.

  4, 5, and 6 are side-view cross-sectional views of the operation mode of the magnetically levitated actuator motor of the present invention. As shown in FIG. 4, when the coil 12 is not energized, the excitation actuator 13 does not generate a magnetic field, and thus is positioned at the bottom of the table 11. When the coil 12 is energized, a magnetic flux is generated in the coil 12 by an electric current. The magnetic actuator 14 is excited by the magnetic flux to generate magnetic field strength. It operates (FIG. 5).

  When the current of the coil 12 is cut off, the excitation actuator 13 has a magnetic field strength by excitation, so that the magnetic elements 14 at the upper and lower ends can be guided to maintain a certain balance. This balance place may be an automatic focusing position (FIG. 6).

  Since the excitation actuator 13 is an excitation member, the magnetic field strength is demagnetized over time. Therefore, in order to maintain the actuator 13 at a certain position for a long time, the current can be intermittently supplied and excited. While the same position is maintained by continuously supplying the same current to the voice coil motor of the prior art, the present invention can greatly reduce the electric consumption.

Furthermore, since the magnetic field strength and the direction of the magnetic field of the excitation member can be changed by excitation with an external magnetic flux, the present invention changes the current and direction of the coil 12 to excite the excitation actuator 13, and changes the operating movement position of the excitation actuator 13. Can change. For this reason, the present invention can be controlled more precisely than a known voice coil motor. The control equation will be described as follows.
The excitation actuator 13 sets the movement amount D of the excitation actuator D to D (d (m (t)) / dt by the magnetic field strength (m) when the current is cut off, the function m (t) of the time m, and the external magnetic field strength Decay. ) Set each.
If the allowable displacement of the excitation actuator 13 is
D _optical = D (d (m (t)) / dtI t = T _holding ). Of these, T _holding indicates a time during which no current is required.

As shown in FIG. 6, the operating position of the excitation actuator 13 is FN (m), FS (m), and W _C from the balance place. Of these, m, m1, and m2 represent the magnetic field strengths of the excitation actuator 13, the upper magnet, and the lower magnet, respectively, and are calculated from the following equations.
F _N (m) = F _S (m) + W _C ,
→ (μ _o / 4π) × (m × m ₁ / (h−L−Z) ² ) = (μ _o / 4π) × (m × m ₂ / Z ² ) + W _c ,

→ Z≡Z (m (t)),
→ D≡D (d (m (t)) / dt).

  The operating movement position of the excitation actuator 13 can be precisely controlled by the above formula. In addition, since it is not necessary to continuously supply current, the electricity consumption can be greatly reduced as compared with a voice coil motor of the known technology.

It is a voice coil motor side view cross section display figure of a well-known technique. It is an elevation display figure of the magnetic levitation actuator motor of the present invention. It is an elevational exploded view of the magnetically levitated actuator motor of the present invention. It is a side view sectional display figure of the magnetic levitation actuator motor operation mode of the present invention. It is a side view sectional display figure of the magnetic levitation actuator motor operation mode of the present invention. It is a side view sectional display figure of the magnetic levitation actuator motor operation mode of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Voice coil motor 95 Lens 110 Actuator 115 Coil 120 Magnet 10 Magnetic levitation actuator motor 11 Base 111 Guide groove 12 Coil 13 Excitation actuator 131 Guide rod 14 Magnetic element

Claims (9)

Including a base, one or more magnetic elements and an excitation actuator;
The base is hollowed out in the center and coiled around the outside.
One or more magnetic elements are provided in the free end opening in the central cutout space of the table,
An excitation actuator using an excitation material is provided in a hollow space in the center of the base and can move up and down. Its characteristics are that the magnetic field strength is maintained at a certain time after excitation, and magnetic flux is generated by energizing the coil. An exciting actuator is a type of magnetic levitation that is excited, generates magnetic field strength, works by attracting or repelling magnetic elements, and can maintain a balanced place in a certain time even after the power is turned off Actuator motor.   2. The magnetic levitation actuator motor according to claim 1, wherein the platform is cylindrical.   2. The magnetic levitation actuator motor according to claim 1, wherein two magnetic elements are provided in the upper and lower end openings of the central part cutout space.   2. The magnetic levitation actuator motor according to claim 1, wherein a thread for screwing a lens into the excitation actuator is provided.   2. The magnetic levitation actuator motor according to claim 1, wherein the magnetic element is a magnet.   2. The magnetic levitation actuator motor according to claim 1, wherein the magnetic element is an electric magnet.   2. The magnetically levitated actuator motor according to claim 1, wherein one or more guide grooves are provided in the central hollow space of the base, the guide rods are provided on the excitation actuator, and the guide rods are accommodated in the guide grooves so as to slide up and down. And a magnetic levitation actuator motor that guides the moving direction of the excitation actuator.   2. The magnetic levitation actuator motor according to claim 1, wherein the magnetic field strength of the excitation actuator is demagnetized as time elapses. Therefore, when the excitation actuator is maintained at a constant position for a long time, the current is intermittently supplied and excited. Features a magnetic levitation actuator motor. In the magnetic levitation actuator motor according to claim 1, by the operation of the excitation actuator and the magnetic element, it is possible to maintain a balanced equation of control of the place,
The excitation actuator has a magnetic field strength (m) when the current is cut off, and a function m (t) of time (t) is determined by the external magnetic field strength Decay, so that the movement amount D of the excitation actuator is D (d (m (t)) / dt) for each,
If the allowable displacement of the excitation actuator is
D _optical = D (d (m (t)) / dtI t = T _holding ), where T _holding indicates the time during which no current is required,
If the operating position of the excitation actuator is FN (m) from the balance location, m, m1, and m2 indicate the magnetic field strength of the excitation actuator, the upper magnet, and the lower magnet, and are calculated from the following equations.
F _N (m) = F _S (m) + W _C ,
→ (μ _o / 4π) × (m × m ₁ / (h−L−Z) ² ) = (μ _o / 4π) × (m × m ₂ / Z ² ) + W _c ,

→ Z≡Z (m (t)),
→ D≡D (d (m (t)) / dt),
A magnetically levitated actuator motor characterized by the above.

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