JP2020089181A - Flat-type voice coil motor - Google Patents

Abstract

To provide a flat-type voice coil motor having a high thrust efficiency.SOLUTION: A flat-type voice coil motor 10 comprises a magnetic unit 14, a first coil 16, and a yoke 12. The magnetic unit 14 includes a first magnet 22 and a second magnet 24 which are provided so as to have an interval in a first direction X1 and so that an N pole is opposite, and a first pole piece 26 that is provided between the first magnet 22 and the second magnet 24, and couples the first magnet 22 and the second magnet 24, and is formed in a flat-shape. The first coil 16 is provided so as to surround the first pole piece 26 in the circumference of the first direction X1, and is formed in the flat-shape. The yoke 12 is provided in a second direction Y1 so as to nip the magnetic unit 14 and the first coil 16, and is connected to the magnetic unit 14 so that the first coil 16 can be moved to the magnetic unit 14 when a DC current is supplied to the first coil 16.SELECTED DRAWING: Figure 1

Description

The present invention relates to a flat type voice coil motor, and more particularly to a flat type voice coil motor used for a vibration isolator or the like.

As an example of this type of conventional technique, Patent Document 1 discloses a voice coil having a pair of permanent magnets provided to face each other and an air-core coil provided between the pair of permanent magnets. A motor is disclosed. The surface of one permanent magnet facing the other permanent magnet is magnetized so that the N pole and the S pole are adjacent to each other. On the surface of the other permanent magnet facing the one permanent magnet, the N pole and the S pole are magnetized so that the one permanent magnet and the different poles face each other. When a current is supplied to the air-core coil, a magnetic field from the N pole of one permanent magnet to the S pole of the other permanent magnet and a magnetic field from the N pole of the other permanent magnet to the S pole of one permanent magnet and the current By this, thrust is generated, and the air core coil moves by the thrust.

International Publication No. 2010/084965

In Patent Document 1, in the vicinity of the boundary between the N pole and the S pole of one permanent magnet, the magnetic field emitted from the N pole of the one permanent magnet is not directed to the S pole of the other permanent magnet but toward the adjacent S pole. .. The same applies to the vicinity of the boundary between the north pole and the south pole of the other permanent magnet. Therefore, in the vicinity of the boundary between the N pole and the S pole of one permanent magnet and between the boundary between the N pole and the S pole of the other permanent magnet, it contributes to the generation of thrust for moving the air-core coil. Cannot form magnetic field. Further, the air-core coil has a portion protruding from between the pair of permanent magnets, and even if a current is supplied to the air-core coil, no thrust is generated in that portion. As described above, the voice coil motor of Patent Document 1 does not have high thrust efficiency.

On the other hand, a small voice coil motor is desired due to the demand for miniaturization of parts.

Therefore, a main object of the present invention is to provide a flat voice coil motor which is small in size and has high thrust efficiency.

In order to achieve the above-mentioned object, a first magnet and a second magnet that are provided with a space in the first direction and that have the same poles facing each other, and a first magnet and a second magnet that are provided between the first magnet and the second magnet are provided. A first pole piece that connects the first magnet and the second magnet, and a flat magnet unit; a first coil that is provided so as to surround the first pole piece around the first direction; Shaped coil unit, and the magnet unit and the coil unit are sandwiched in the second direction orthogonal to the first direction, and when a current is supplied to the coil unit, one of the magnet unit and the coil unit becomes the other. A flat voice coil motor is provided, which includes a yoke connected to the other so as to be movable relative to the other.

In the present invention, the first magnet and the second magnet are provided so that the same poles face each other, and the first coil is provided so as to surround the first pole piece. Therefore, the magnetic field formed by the first magnet and the second magnet extends radially so as to connect the first magnet (second magnet) and the yoke when viewed from the first direction, and passes through the first coil. It is formed. In other words, the magnetic field formed by the first magnet and the second magnet is formed so as to pass through the entire circumference of the first coil when viewed from the first direction. Therefore, the thrust efficiency can be increased. Moreover, the magnet unit and the coil unit are formed in a flat shape. Therefore, a flat voice coil motor having a small size can be obtained.

Preferably, the first coil is provided so as not to protrude from the yoke when viewed in the second direction. In this case, since the entire first coil can be used effectively, the thrust efficiency can be further increased.

Also preferably, a direct current is supplied to the coil unit. In this case, one of the magnet unit and the coil unit can be moved by a desired amount with respect to the other by adjusting the magnitude of the direct current supplied to the coil unit. Therefore, the flat voice coil motor can be preferably used for positioning.

More preferably, the magnet unit is provided on a side opposite to the first magnet in the first direction as viewed from the second magnet, spaced apart from the second magnet, and provided with a third magnet facing the same pole. The coil unit further includes a magnet and a second pole piece provided between the second magnet and the third magnet and connecting the second magnet and the third magnet, and the coil unit includes the second pole piece around the first direction. It further has the 2nd coil provided so that it may surround, and the coil connection part which connects the 1st coil and the 2nd coil. In this case, the direction of the thrust generated when the current is supplied to the first coil and the direction of the thrust generated when the current is supplied to the second coil are the same, By supplying the electric current to the flat voice coil motor, the thrust obtained by the flat voice coil motor can be increased.

Preferably, the second coil is provided so as not to protrude from the yoke when viewed in the second direction. In this case, since the entire second coil can be effectively used, the thrust efficiency can be further increased.

“Flatness” in the flat type voice coil motor according to the present invention means flatness f=2h/(a1+a2) of the flat type voice coil motor (h is a dimension in the second direction, a1 is a dimension in the first direction, and a2 is When defined as (dimension in the third direction), it means that f≦0.7 is satisfied. The flatness is preferably f≦0.6. The third direction means a direction orthogonal to the first direction and the second direction.

According to the present invention, it is possible to obtain a flat voice coil motor that is small in size and has high thrust efficiency.

It is a figure showing the flat type voice coil motor concerning one embodiment of this invention, (a) is a partial section side view, (b) is an A1-A1 line sectional view of (a), and (c). ) Is a plan view. It is a figure which shows the flat type voice coil motor which concerns on other embodiment of this invention, (a) is a partial cross section side view, (b) is the A2-A2 sectional view taken on the line of (a), ( c) is a plan view. It is a figure which shows the flat type voice coil motor which concerns on other embodiment of this invention, (a) is a partial cross section side view, (b) is the A3-A3 line sectional view of (a), ( c) is a plan view. It is a figure showing an example of a flat type voice coil motor concerning this invention, (a) is a partial section side view, (b) is an A4-A4 line sectional view of (a), and (c) is. It is a top view. It is a figure which shows the voice coil motor of a comparative example, (a) is a partial cross section side view, (b) is the A5-A5 sectional view taken on the line of (a), (c) is a top view. 6 is a table showing a comparison result of thrust efficiencies of an example of the flat type voice coil motor according to the present invention and a voice coil motor of a comparative example.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1, a flat voice coil motor 10 according to an embodiment of the present invention includes a yoke 12, a magnet unit 14, and a first coil 16 (corresponding to a coil unit).

The yoke 12 has a pair of facing portions 18 and 19 and a yoke connecting portion 20. The facing portions 18 and 19 each extend in the first direction X1 and are formed in a flat plate shape. The facing portions 18 and 19 are provided so as to face each other and sandwich the magnet unit 14 and the first coil 16 in the second direction Y1 orthogonal to the first direction X1. The yoke connecting portion 20 connects one ends of the facing portions 18 and 19 in the first direction X1. The yoke connecting portion 20 is larger than the magnet unit 14 and the first coil 16 in the third direction Z1 orthogonal to the first direction X1 and the second direction Y1.

The magnet unit 14 has a first magnet 22, a second magnet 24, and a first pole piece 26, and is formed in a flat shape. The magnet unit 14 is provided so as not to protrude from the facing portions 18 and 19 when viewed in the second direction Y1. The first magnet 22 and the second magnet 24 each extend in the third direction Z1 and are formed in a prismatic shape. The first magnet 22 and the second magnet 24 are set to the same magnet, that is, the same shape, the same size, and the same kind as each other. The first magnet 22 and the second magnet 24 are provided at intervals in the first direction X1 and with the N poles facing each other. The S pole side of the second magnet 24 is connected to the yoke connecting portion 20. The first pole piece 26 is provided between the first magnet 22 and the second magnet 24, and connects the first magnet 22 and the second magnet 24. The first pole piece 26 is larger than the first magnet 22 and the second magnet 24 in the first direction X1, and is set to have the same dimensions as the first magnet 22 and the second magnet 24 in the second direction Y1 and the third direction Z1. , Formed in a flat shape. A ferromagnetic material such as iron is used for the first pole piece 26. In such a magnet unit 14, the magnetic field formed by the first magnet 22 and the second magnet 24 (see the dotted arrow in FIGS. 1A and 1B) is radial and first when viewed from the first direction X1. It is formed so as to pass through one coil 16.

The first coil 16 is wound around the first pole piece 26 around the first direction X1 and is formed in a flat shape. The first coil 16 is formed in a substantially rectangular shape and an annular shape when viewed in the first direction X1. The first coil 16 is provided so as to be movable with respect to the magnet unit 14 and the yoke 12. The first coil 16 is provided so as not to protrude from the facing portions 18 and 19 when viewed in the second direction Y1. The first coil 16 is larger than the first pole piece 26 in the first direction X1. A wire or the like (not shown) for supplying a direct current to the first coil 16 is connected to the first coil 16.

A bracket 28 is connected to the outer surface of the first coil 16. An arbitrary positioned member (not shown) positioned by the flat voice coil motor 10 is attached to the bracket 28.

In such a flat type voice coil motor 10, when a direct current is supplied to the first coil 16, a thrust force in the first direction X1 is generated by the magnetic field formed by the first magnet 22 and the second magnet 24 and the direct current. The generated thrust causes the first coil 16 to move in the first direction X1 with respect to the magnet unit 14 and the yoke 12 (see arrow B1 in FIG. 1A). In the state viewed from the direction shown in FIG. 1B, when a direct current is supplied in the clockwise direction, a thrust is generated in a direction away from the yoke connecting portion 20, and the first coil 16 moves away from the yoke connecting portion 20. Moving. When a direct current is supplied counterclockwise in the state viewed from the direction shown in FIG. 1B, thrust is generated in the direction approaching the yoke connecting portion 20, and the first coil 16 is moved in the direction approaching the yoke connecting portion 20. Moves. The member to be positioned also moves in the first direction X1 as the first coil 16 moves in the first direction X1. By adjusting the magnitude of the direct current supplied to the first coil 16, the magnitude of the thrust generated can be adjusted. In this way, by adjusting the direction and magnitude of the direct current supplied to the first coil 16, the positioned member can be positioned at a desired position.

According to such a flat type voice coil motor 10, the first magnet 22 and the second magnet 24 are provided so that the same poles face each other, and the first coil 16 is provided so as to surround the first pole piece 26. Be done. Therefore, as shown in FIG. 1B, the magnetic field formed by the first magnet 22 and the second magnet 24 causes the first magnet 22 (second magnet 24) and the yoke 12 to be seen from the first direction X1. It is formed so as to extend radially so as to connect and pass through the first coil 16. In other words, the magnetic field formed by the first magnet 22 and the second magnet 24 is formed so as to pass through the entire circumference of the first coil 16 when viewed in the first direction X1. Therefore, the thrust efficiency can be increased. Further, the magnet unit 14 and the first coil 16 are formed in a flat shape. Therefore, it is possible to obtain the flat-type voice coil motor 10 that is small and has a low flatness f.

Since the first coil 16 is provided so as not to protrude from the yoke 12 when viewed in the second direction Y1, the entire first coil 16 can be effectively used and the thrust efficiency can be further increased.

By adjusting the magnitude of the direct current supplied to the first coil 16, the first coil 16 can be moved by a desired amount with respect to the magnet unit 14 and the yoke 12. Therefore, the flat voice coil motor 10 can be preferably used for positioning.

The above-described effects can be similarly achieved in the embodiments shown in FIGS. 2 and 3 described later.

A flat type voice coil motor 100 according to another embodiment of the present invention will be described with reference to FIG. The same parts as those of the flat voice coil motor 10 described above are designated by the same reference numerals, and detailed description thereof will be omitted. The flat type voice coil motor 100 includes a yoke 12, a magnet unit 102, and a coil unit 104.

The magnet unit 102 has a first magnet 22, a second magnet 24, a third magnet 106, a first pole piece 108, and a second pole piece 110, and is formed in a flat shape. In the first direction X2, the distance between the first magnet 22 and the second magnet 24 is set smaller than the distance between the first magnet 22 and the second magnet 24 in the flat type voice coil motor 10. The third magnet 106 is set to the same magnet as the first magnet 22 and the second magnet 24, that is, the same shape, the same size, and the same type. The third magnet 106 is spaced from the second magnet 24 on the side opposite to the first magnet 22 in the first direction X2 when viewed from the second magnet 24, and the second magnet 24 and the S pole face each other. It is provided in. In the first direction X2, the distance between the second magnet 24 and the third magnet 106 is set to be equal to the distance between the first magnet 22 and the second magnet 24. The N pole side of the third magnet 106 is connected to the yoke connecting portion 20. The first pole piece 108 is different from the first pole piece 26 in that it is smaller than the first magnet 22 and the second magnet 24 in the first direction X2. The second pole piece 110 is set to have the same pole piece as the first pole piece 108, that is, the same shape, the same size, and the same type. The second pole piece 110 is provided between the second magnet 24 and the third magnet 106, and connects the second magnet 24 and the third magnet 106. In such a magnet unit 102, the magnetic field formed by the first magnet 22 and the second magnet 24 (see the dotted arrow in FIG. 2A) is radial and the first coil 112 (see the first direction X2). It is formed so as to pass through (described later). The magnetic field formed by the second magnet 24 and the third magnet 106 (see the dotted arrow in FIGS. 2A and 2B) is radial and passes through the second coil 114 (described later) when viewed in the first direction X2. Is formed. The magnetic field formed by the second magnet 24 and the third magnet 106 is formed in the opposite direction to the magnetic field formed by the first magnet 22 and the second magnet 24.

The coil unit 104 has a first coil 112, a second coil 114, and a coil connecting portion 116. The first coil 112 differs from the first coil 16 in that the first coil 112 is set to have the same dimensions as the first pole piece 108 in the first direction X2. The second coil 114 is set to have the same coil as the first coil 112, that is, the same shape, the same size, and the same type, and is wound around the second pole piece 110 around the first direction X2. Therefore, the second coil 114 is set to have the same size as the second pole piece 110 in the first direction X2. The second coil 114 is provided so as not to protrude from the yoke 12 when viewed in the second direction Y2. The coil connecting portion 116 is provided between the first coil 112 and the second coil 114, and connects the first coil 112 and the second coil 114. The first coil 112 and the second coil 114 are connected so that the positional relationship of the first coil 112 with respect to the first pole piece 108 and the positional relationship of the second coil 114 with respect to the second pole piece 110 are the same. The coil connecting portion 116 is formed in a substantially quadrangular and annular shape so as to overlap the first coil 112 and the second coil 114 when viewed in the first direction X2. The coil connecting portion 116 is set to have the same size as the second magnet 24 in the first direction X2.

The bracket 28 is connected to the outer surface of the coil connecting portion 116. An arbitrary positioned member (not shown) positioned by the flat voice coil motor 100 is attached to the bracket 28.

In such a flat type voice coil motor 100, when a direct current is supplied to the first coil 112, a thrust force is generated in the first direction X2 by the magnetic field formed by the first magnet 22 and the second magnet 24 and the direct current. When a direct current is generated and supplied to the second coil 114, a thrust is generated in the first direction X2 by the magnetic field formed by the second magnet 24 and the third magnet 106 and the direct current. The thrust causes the coil unit 104 to move in the first direction X2 with respect to the magnet unit 102 and the yoke 12 (see arrow B2 in FIG. 2A). When the direct current is supplied to the first coil 112 in the clockwise direction and the direct current is supplied to the second coil 114 in the counterclockwise direction in the state viewed from the direction shown in FIG. A thrust is generated in the direction, and the coil unit 104 moves in the direction away from the yoke connecting portion 20. When the direct current is supplied to the first coil 112 in the counterclockwise direction and the direct current is supplied to the second coil 114 in the clockwise direction in the state viewed from the direction shown in FIG. 2B, the yoke coupling portion 20 is approached. A thrust is generated in the direction, and the coil unit 104 moves in the direction approaching the yoke connecting portion 20. By adjusting the direction and the magnitude of the direct current supplied to the first coil 112 and the second coil 114, the positioned member can be positioned at a desired position.

According to such a flat voice coil motor 100, the direction of the thrust generated when the direct current is supplied to the first coil 112 and the direction of the thrust generated when the direct current is supplied to the second coil 114. By supplying a direct current to the first coil 112 and the second coil 114 so that the same becomes, the thrust obtained by the flat voice coil motor 100 can be increased.

Since the second coil 114 is provided so as not to protrude from the yoke 12 when viewed in the second direction Y2, the entire second coil 114 can be effectively used and the thrust efficiency can be further increased.

The first magnet 22 and the third magnet 106 are the same magnet, the first pole piece 108 and the second pole piece 110 are the same pole piece, and the first coil 112 and the second coil 114 are the same coil. The positional relationship of the first coil 112 with respect to the first pole piece 108 and the positional relationship of the second coil 114 with respect to the second pole piece 110 are the same. Thereby, the distribution of the magnetic field passing through the first coil 112 and the distribution of the magnetic field passing through the second coil 114 can be equalized except for the orientation.

A flat type voice coil motor 200 according to another embodiment of the present invention will be described with reference to FIG. The same parts as those of the flat voice coil motor 10 described above are designated by the same reference numerals, and detailed description thereof will be omitted. The flat voice coil motor 200 includes a yoke 12, a magnet unit 14, and a first coil 202 (corresponding to a coil unit).

In the flat type voice coil motor 200, the magnet unit 14 is provided so as to be movable with respect to the first coil 202 and the yoke 12 without being connected to the yoke connecting portion 20.

The first coil 202 is wound in a substantially quadrangular and annular shape when viewed in the first direction X3. Both sides of the first coil 202 in the second direction Y3 are fixed to the facing portions 18 and 19. The magnet unit 14 is arranged inside the first coil 202 so that the first coil 202 surrounds the first pole piece 26 around the first direction X3.

A bracket 28 is connected to the outer surface of the first magnet 22. An arbitrary positioned member (not shown) positioned by the flat voice coil motor 200 is attached to the bracket 28.

In such a flat type voice coil motor 200, when a direct current is supplied to the first coil 202, the magnetic field formed by the first magnet 22 and the second magnet 24 and the direct current generate a thrust in the first direction X3. The generated thrust causes the magnet unit 14 to move in the first direction X3 with respect to the first coil 202 and the yoke 12 (see arrow B3 in FIG. 3A). In the state viewed from the direction shown in FIG. 3B, if a direct current is supplied to the first coil 202 in the clockwise direction, a thrust is generated in the direction approaching the yoke connecting portion 20 and in the direction approaching the yoke connecting portion 20. The magnet unit 14 moves. In the state viewed from the direction shown in FIG. 3B, if a direct current is supplied counterclockwise to the first coil 202, a thrust is generated in a direction away from the yoke connecting portion 20 and a direction away from the yoke connecting portion 20. The magnet unit 14 moves. As the magnet unit 14 moves in the first direction X3, the bracket 28 connected to the magnet unit 14 also moves in the first direction X3. In this way, by adjusting the direction and magnitude of the direct current supplied to the first coil 202, the positioned member can be positioned at a desired position.

According to such a flat type voice coil motor 200, it is possible to perform positioning of a positioned member that is heavier than when the coil unit is moved.

Referring to FIGS. 4 to 6, comparison results of thrust efficiency between flat type voice coil motor 300 (see FIG. 4) according to the present invention and voice coil motor 1 of the comparative example (see FIG. 5) (see FIG. 6). ) Will be described.

Referring to FIGS. 4 and 6, the flat type voice coil motor 300 according to the present invention has a width (W: dimension in the first direction) of 75 mm, a depth (L: dimension in the third direction) of 110 mm, and a height (H). : Dimension in the second direction) 47 mm. The flatness f in this case is f=2H/(W+L)=0.51. The flat-type voice coil motor 300 has substantially the same configuration as the flat-type voice coil motor 10 although the dimensions are different. Therefore, the parts corresponding to the flat-type voice coil motor 10 have “a” added to the end of the corresponding reference numeral. Therefore, detailed description will be omitted. In addition to the yoke connecting portion 20a, the yoke 12a has a yoke connecting portion 21a that connects the other end portions of the facing portions 18a and 19a to each other and is connected to the S pole side of the first magnet 22a. The NdFeB system sintered magnet was used for the 1st magnet 22a and the 2nd magnet 24a. When a direct current is supplied to the first coil 16a, thrust is generated and the thrust moves the first coil 16a (see arrow B4 in FIG. 4A). The length in the winding direction of the portion of the first coil 16a where the thrust in the arrow B4 direction is generated is D1 mm (see FIG. 4B).

On the other hand, referring to FIGS. 5 and 6, the voice coil motor 1 of the comparative example is set to have a width (W) of 75 mm, a depth (L) of 110 mm, and a height (H) of 60 mm. The flatness f in this case is f=2H/(W+L)=0.65. The voice coil motor 1 has a yoke 2, a magnet unit 3 and a coil 4. The yoke 2 has a pair of facing portions 5a and 5b facing each other, and yoke connecting portions 6a and 6b connecting one end portions and the other end portions of the pair of facing portions 5a and 5b. The magnet unit 3 has a first magnet 7 provided on the inner surface of the facing portion 5a and a second magnet 8 facing the first magnet 7 and provided on the inner surface of the facing portion 5b. The surface of the first magnet 7 facing the second magnet 8 is magnetized so that the N pole and the S pole are adjacent to each other. On the surface of the second magnet 8 facing the first magnet 7, the N pole and the S pole are magnetized so that the first magnet 7 and the different poles face each other. NdFeB-based sintered magnets were used for the first magnet 7 and the second magnet 8. The coil 4 is formed in a substantially quadrangular and annular shape in a plan view, and is provided between the first magnet 7 and the second magnet 8. Therefore, the magnetic field from the N pole of the first magnet 7 to the S pole of the second magnet 8 and the magnetic field from the N pole of the second magnet 8 to the S pole of the first magnet 7 pass through the coil 4, respectively. Formed (see the dotted arrow in FIG. 5(a)). When a direct current is supplied to the coil 4, thrust is generated, and the coil 4 is moved by the thrust (see arrow B5 in FIG. 5A). The length in the winding direction of the portion of the coil 4 in which the thrust in the arrow B5 direction is generated is 2×D2 mm (see FIG. 5C).

Comparing the flat voice coil motor 300 and the voice coil motor 1, the height (H) of the flat voice coil motor 300 is set smaller than the height (H) of the voice coil motor 1. Therefore, the volume of the flat voice coil motor 300 is smaller than the volume of the voice coil motor 1, and the flat voice coil motor 300 is smaller than the voice coil motor 1. Further, the flatness f of the flat voice coil motor 300 is smaller than the flatness f of the voice coil motor 1, and the flat voice coil motor 300 is flatter than the voice coil motor 1. Further, the length (D1 mm) in the flat type voice coil motor 300 is longer than the length (2×D2 mm) in the voice coil motor 1, and about 1.2 times the length (2×D2 mm) in the voice coil motor 1. It will be 5 times. In such two flat voice coil motors 300 and 1, the flat voice coil can be obtained by supplying a DC rated current to the first coil 16a of the flat voice coil motor 300 and the coil 4 of the voice coil motor 1. The motor 300 generated a thrust of 45N, and the voice coil motor 1 generated a thrust of 25N. When comparing the thrust efficiency (force / volume) in this case, flat type in the voice coil motor 300 0.12 N / cm ^3, and the became the voice coil motor 1 in 0.05 N / cm ^3.

As described above, the flat type voice coil motor 300 according to the present invention has a higher thrust efficiency than the voice coil motor 1 of the comparative example, although it is smaller and thinner than the voice coil motor 1 of the comparative example. ..

In the above-described embodiment, the case where the N pole of the first magnet 22 and the N pole of the second magnet 24 are provided so as to face each other has been described. However, the present invention is not limited to this, and the S pole and the The two magnets 24 may be provided so as to face the south pole.

In the above-described embodiment, the case where the S pole of the second magnet 24 and the S pole of the third magnet 106 are provided so as to face each other has been described. However, the present invention is not limited to this, and the N pole of the second magnet 24 and the The three magnets 106 may be provided so as to face the N pole of the three magnets.

In the above-described embodiment, the case where the DC current is supplied to the coil unit has been described, but the present invention is not limited to this, and the AC current may be supplied to the coil unit. In this case, it is possible to configure a flat type voice coil motor in which the movable one of the magnet unit and the coil unit vibrates with respect to the one that does not move.

In the above-described embodiment, the case where the first coil 16 is larger than the first pole piece 26 in the first direction X1 has been described, but the present invention is not limited to this. For example, the first coil may be set to have the same size as the first pole piece 26 or smaller than the first pole piece 26 in the first direction X1.

In the above-described embodiment, the first coil 112 has the same dimension as the first pole piece 108 in the first direction X2, and the second coil 114 has the same dimension as the second pole piece 110 in the first direction X2. Although the case has been described, the present invention is not limited to this. For example, the first coil may be set larger or smaller than the first pole piece 108 in the first direction X2, and the second coil may be set larger or smaller than the second pole piece 110 in the first direction X2.

In the above-described embodiment, the first magnet 22 and the second magnet 24 in the flat voice coil motors 10, 200, and the first magnet 22, the second magnet 24, and the third magnet 106 in the flat voice coil motor 100 are The case where the same magnets, that is, the same shape, the same size, and the same kind are set to each other has been described, but the present invention is not limited to this.

In the above-described embodiment, the first magnet 22 and the third magnet 106 are the same magnet, the first pole piece 108 and the second pole piece 110 are the same pole piece, and the first coil 112 and the second coil 114 are the same. Are the same coil, and the case where the positional relationship of the first coil 112 with respect to the first pole piece 108 and the positional relationship of the second coil 114 with respect to the second pole piece 110 are the same has been described, but the present invention is not limited to this.

In the above-described embodiment, the case where the first coil and the second coil are provided so as not to protrude from the yoke when viewed in the second direction has been described, but the present invention is not limited to this. The first coil and the second coil may be provided so as to protrude from the yoke when viewed in the second direction.

10,100,200,300 Flat voice coil motor 12,12a Yoke 14,102 Magnet unit 16,112,202 First coil 18,18a,19,19a Opposing part 20,20a,21a Yoke connecting part 22,22a 1 magnet 24,24a 2nd magnet 26,108 1st pole piece 28 bracket 104 coil unit 106 3rd magnet 110 2nd pole piece 114 2nd coil 116 coil connection part

Claims (5)

A first magnet and a second magnet that are provided with a space in the first direction so that the same poles face each other; and the first magnet and the second magnet that are provided between the first magnet and the second magnet A magnet unit having a first pole piece for connecting magnets and formed in a flat shape;
A flat coil unit having a first coil provided so as to surround the first pole piece around the first direction, and the magnet unit and the second unit in a second direction orthogonal to the first direction. A yoke that is provided so as to sandwich the coil unit and that is connected to the other of the magnet unit and the coil unit so that when the coil unit is supplied with an electric current, one of the magnet unit and the coil unit is movable with respect to the other, Flat type voice coil motor. The flat voice coil motor according to claim 1, wherein the first coil is provided so as not to protrude from the yoke when viewed from the second direction. The flat voice coil motor according to claim 1, wherein a direct current is supplied to the coil unit. The magnet unit is provided on the side opposite to the first magnet in the first direction viewed from the second magnet so as to be spaced apart from the second magnet and have the same pole as the second magnet. Further comprising a third magnet and a second pole piece provided between the second magnet and the third magnet and connecting the second magnet and the third magnet,
The coil unit further includes a second coil provided so as to surround the second pole piece around the first direction, and a coil connecting portion that connects the first coil and the second coil. 4. The flat voice coil motor according to any one of 1 to 3. The flat voice coil motor according to claim 4, wherein the second coil is provided so as not to protrude from the yoke when viewed from the second direction.

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