Voice coil motor

Abstract

This voice coil motor is provided with: a cylindrical or columnar inner yoke; a cylindrical outer yoke surrounding the inner yoke so as to form a cylindrical gap between the outer yoke and the inner yoke; a cylindrical coil disposed in the gap; a magnet disposed on the inner side of the coil in a state of being in contact with the inner yoke, or disposed on the outer side of the coil in a state of being in contact with the outer yoke; a first connection yoke that connects one end of the inner yoke in the axial direction and one end of the outer yoke in the axial direction; and a second connection yoke that connects the other end of the inner yoke in the axial direction and the other end of the outer yoke in the axial direction. At least one of the first connection yoke and the second connection yoke has a plurality of yoke pieces arranged in a tubular shape so as to connect the inner yoke and the outer yoke, and the plurality of yoke pieces are configured from members independent of the inner yoke and the outer yoke so as to be attached to the inner yoke and the outer yoke. A gap for taking out the output of the voice coil motor is provided between adjacent yoke pieces.

Description

Technical Field

[0001] This disclosure relates to voice coil motors. Background Technology

[0002] Conventional voice coil motors have a structure in which one end of a cylindrical inner yoke is connected axially via a connecting yoke at one end, and the other end of a cylindrical outer yoke is configured to form a cylindrical gap between the inner yoke and the inner yoke. The connecting yoke at one end is integrally formed with the outer yoke, closing the opening at one axial end of the gap. The opening at the other axial end of the gap is open to allow the output of a coil configured to move axially along the gap to be retrieved.

[0003] In the case of a voice coil motor with this structure, to increase the axial thrust of the voice coil motor, a connecting yoke on the other end connects the other end of the inner yoke and the other end of the outer yoke along their axial direction. The connecting yoke on the other end is integrally formed with the outer yoke, closing the opening on the other end of the axial direction of the gap. However, as mentioned above, the other end of the axial direction of the gap needs to be open; therefore, the connecting yoke on the other end has a through hole for extracting the coil output. Typically, a connecting member passes through the through hole of the connecting yoke on the other end, connecting the drive unit driven by the voice coil motor output and the coil.

[0004] In voice coil motors with the aforementioned through-hole, the connecting component needs to pass through the through-hole during assembly. Therefore, the connecting component must be a structure capable of passing through the through-hole, and this must be considered in the design. In other words, in the case of conventional voice coil motors, the design freedom for the connecting component is limited.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2000-23442 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] To address the aforementioned issues, a voice coil motor that can increase thrust while simultaneously enhancing design freedom is desired.

[0010] Solution for solving the problem

[0011] The voice coil motor disclosed herein comprises: a cylindrical or cylindrical inner yoke; an outer yoke, which is cylindrical and surrounds the inner yoke in such a way that a cylindrical gap is formed between the outer yoke and the inner yoke; a cylindrical coil disposed in the gap; a magnet disposed inside the coil in contact with the inner yoke, or disposed outside the coil in contact with the outer yoke; a first connecting yoke that connects one axial end of the inner yoke to one axial end of the outer yoke; and a second connecting yoke that connects the other axial end of the inner yoke to the other axial end of the outer yoke. At least one of the first connecting yoke and the second connecting yoke has a plurality of yoke plates arranged in a cylindrical shape to connect the inner yoke and the outer yoke. The plurality of yoke plates are constructed of components independent of the inner yoke and the outer yoke, and gaps are provided between adjacent yoke plates for extracting the output of the voice coil motor. Attached Figure Description

[0012] Figure 1 This is a schematic perspective view of a voice coil motor according to one embodiment of the present invention.

[0013] Figure 2 yes Figure 1 A-A' sectional view.

[0014] Figure 3 yes Figure 2 The B-B' sectional view.

[0015] Figure 4 yes Figure 3 The C-C' sectional view.

[0016] Figure 5 This is a schematic perspective view of a voice coil motor according to one embodiment of the present invention, showing the state before the yoke plates are mounted on the inner and outer yokes.

[0017] Figure 6 This is a schematic perspective view of a voice coil motor according to one embodiment of the present invention, showing the state in which yoke plates are mounted on the inner and outer yokes.

[0018] Figure 7 This is a schematic longitudinal sectional view showing a modified example 1 of the voice coil motor of the present invention.

[0019] Figure 8 This is a schematic longitudinal sectional view showing a modified example 2 of the voice coil motor of the present invention. Detailed Implementation

[0020] The following description, with reference to the accompanying drawings, illustrates one aspect of a voice coil motor according to this disclosure. Figures 1 to 6 The voice coil motor 1 of this embodiment will be described below. The voice coil motor 1 includes an inner yoke 2, an outer yoke 3, a coil 4, a magnet 5, a first connecting yoke 6, a second connecting yoke 7, and a connecting member 8. Hereinafter, the axial direction J1 will be defined as the vertical direction. One end of the axial direction J1 will be defined as the lower end J11, and the other end of the axial direction J1 will be defined as the upper end J12.

[0021] The inner yoke 2 is cylindrical or cylindrical. In the example shown, the inner yoke 2 is cylindrical, with the axis J1 along the vertical direction. Alternatively, the inner yoke 2 can also be cylindrical. In this case, the inner yoke 2 is typically cylindrical.

[0022] The outer magnetic yoke 3 is cylindrical. In the example shown, the outer magnetic yoke 3 is cylindrical, with its axial direction J1 along the vertical direction. The inner diameter of the outer magnetic yoke 3 is larger than the diameter of the cylindrical inner magnetic yoke 2. For example... Figure 2 and Figure 4 As shown, the outer magnetic yoke 3 is arranged on the same axis as the inner magnetic yoke 2, surrounding it. With the outer magnetic yoke 3 surrounding the inner magnetic yoke 2, a cylindrical gap 9 is formed between the outer magnetic yoke 3 and the inner magnetic yoke 2. This gap 9 is cylindrical and is the space between the inner circumferential surface 10 of the outer magnetic yoke 3 and the outer circumferential surface 11 of the inner magnetic yoke 2. The upper opening J12 of the cylindrical gap 9 opens upwards, and the lower opening J11 of the cylindrical gap 9 opens downwards.

[0023] Coil 4 is cylindrical. In the example shown, coil 4 is cylindrical, with its axis J1 running vertically. The inner diameter of coil 4 is larger than the diameter of the inner yoke 2, and the outer diameter of coil 4 is smaller than the inner diameter of the outer yoke 3. For example... Figure 2 and Figure 4 As shown, coil 4 is arranged on the same axis as inner yoke 2 and outer yoke 3 in the gap 9 between inner yoke 2 and outer yoke 3.

[0024] Magnet 5 is cylindrical. In the example shown, magnet 5 is cylindrical, with its axis J1 running vertically. The outer diameter of magnet 5 is smaller than the inner diameter of coil 4. Figure 2 and Figure 4 As shown, the magnet 5 is fixed to the inner yoke 2 with its inner circumferential surface 12 in contact with the outer circumferential surface 11 of the inner yoke 2. While fixed to the inner yoke 2, the magnet 5 is arranged on the same axis as both the inner yoke 2 and the outer yoke 3. The magnet 5, while fixed to the inner yoke 2, is surrounded by the coil 4 located in the gap 9. Thus, the magnet 5 is arranged inside the coil 4 in contact with the inner yoke 2. Furthermore, the magnet 5 in this embodiment is a permanent magnet.

[0025] The first connecting yoke 6 is circular and connects the inner yoke 2 and the outer yoke 3 at a position J11 lower than the magnet 5 located on the inner yoke 2. Specifically, the inner yoke 2 and the outer yoke 3 are fixed to the first connecting yoke 6 with their lower J11 surfaces 13 and 14 contacting the upper J12 surface 15 of the first connecting yoke 6. For example, the inner yoke 2 and the outer yoke 3 are fixed to the first connecting yoke 6 by screws. With the inner yoke 2 and the outer yoke 3 fixed to the first connecting yoke 6, a gap 9 is formed between the inner yoke 2 and the outer yoke 3. In this way, the first connecting yoke 6 connects one end of the inner yoke 2 along the axial direction J1 and one end of the outer yoke 3 along the axial direction J1.

[0026] like Figure 3 As shown, the second connecting yoke 7 has a plurality of yoke plates 16 arranged in a cylindrical shape to connect the inner yoke 2 and the outer yoke 3. The plurality of yoke plates 16 are constructed from components independent of the inner yoke 2 and the outer yoke 3, respectively, and are mounted on the inner yoke 2 and the outer yoke 3. In the example shown, the plurality of yoke plates 16 are generally fan-shaped plates when viewed from above. Specifically, the yoke plates 16 have a plate surface 17 located on the upper side J12, a plate surface 18 located on the lower side J11, and four end faces 19, 20, 21, and 22 connecting the plate surface 17 located on the upper side J12 and the plate surface 18 located on the lower side J11.

[0027] End face 19 connects one circumferential end of plate surface 17 to one circumferential end of plate surface 18, and end face 20 connects the other circumferential end of plate surface 17 to the other circumferential end of plate surface 18. End faces 19 and 20 are inclined in a manner that they move away from each other as they move outward toward the radial direction K1. That is, the circumferential length between end faces 19 and 20 increases as they move outward toward the radial direction K1. End face 21 connects the inner radial end of plate surface 17 to the inner radial end of plate surface 18, and end face 22 connects the outer radial end of plate surface 17 to the outer radial end of plate surface 18. End face 21 is a curved surface that is concave in an arc shape outward toward the radial direction K1 when viewed from above, and end face 22 is a curved surface that is bulging in an arc shape outward toward the radial direction K1 when viewed from above.

[0028] Multiple magnetic yoke pieces 16 are respectively positioned above the magnet 5 located on the inner magnetic yoke 2 by J12, between the inner magnetic yoke 2 and the outer magnetic yoke 3. Specifically, the magnetic yoke pieces 16 are fixed to the inner magnetic yoke 2 and the outer magnetic yoke 3 with their end faces 21 in contact with the outer peripheral surface 11 of the inner magnetic yoke 2 and their end faces 22 in contact with the inner peripheral surface 10 of the outer magnetic yoke 3. For example, the magnetic yoke pieces 16 are pressed between the inner magnetic yoke 2 and the outer magnetic yoke 3 and are installed on the inner magnetic yoke 2 and the outer magnetic yoke 3 by adhesive. In this way, the second connecting magnetic yoke 7 connects the other end of the axial direction J1 of the inner magnetic yoke 2 and the other end of the axial direction J1 of the outer magnetic yoke 3.

[0029] With the second connecting yoke 7 installed on the inner yoke 2 and the outer yoke 3, the end face 22 of the yoke piece 16 is located on the outer yoke 3 side, and the end face 21 of the yoke piece 16 is located on the inner yoke 2 side. Therefore, the circumferential length of the end of the yoke piece 16 located on the outer yoke 3 side is greater than the circumferential length of the end of the yoke piece 16 located on the inner yoke 2 side. As described above, the yoke piece 16 is disposed between the inner yoke 2 and the outer yoke 3. Therefore, when fixing the yoke piece 16, the end face 22 of the yoke piece 16 located on the outer yoke 3 side is in contact with the inner circumferential surface 10 of the outer yoke 3, and the end face 21 of the yoke piece 16 located on the inner yoke 2 side is in contact with the outer circumferential surface 11 of the inner yoke 2.

[0030] With the second connecting yoke 7 installed on the inner yoke 2 and the outer yoke 3, adjacent yoke plates 16, 16 do not contact each other. That is, there is a gap between the end faces 19, 20 of adjacent yoke plates 16, 16. Therefore, a gap 23 extending vertically is provided between adjacent yoke plates 16, 16. This gap 23 is used to extract the output of the voice coil motor 1. In the example shown, a connecting member 8 (not shown) that connects the drive unit driven by the output of the voice coil motor 1 to the coil 4 passes through the gap 23 between adjacent yoke plates 16, 16.

[0031] The connecting member 8 has a drive-side connecting piece 24 located at the upper side J12, a motor-side connecting piece 25 located at the lower side J11, and a plurality of connecting pieces 26 connecting the drive-side connecting piece 24 and the motor-side connecting piece 25. The drive-side connecting piece 24 is a circular plate-shaped plate arranged with its surface facing up and down. The drive unit is connected to the drive-side connecting piece 24. The motor-side connecting piece 25 is a short cylindrical shape with an opening at the lower side J11. The upper wall 27 of the motor-side connecting piece 25 has a circular through hole 28 extending up and down. The coil 4 is supported at the lower end J11 of the motor-side connecting piece 25. With the coil 4 supported by the motor-side connecting piece 25, the axial direction J1 of the coil 4 is along the up and down direction. The plurality of connecting pieces 26 are all plate-shaped. The upper end J12 of the connecting piece 26 is connected to the drive-side connecting piece 24, and the lower end J11 of the connecting piece 26 is connected to the upper wall 27 of the motor-side connecting piece 25.

[0032] With the drive-side connecting piece 24 and the motor-side connecting piece 25 connected by connecting piece 26, the drive-side connecting piece 24 and the motor-side connecting piece 25 are arranged separately in the vertical direction. Multiple connecting pieces 26, while connected to the drive-side connecting piece 24 and the motor-side connecting piece 25, are separated in the circumferential direction of the drive-side connecting piece 24 and the circumferential direction of the motor-side connecting piece 25. That is, there is a gap between adjacent connecting pieces 26. Due to this structure, the connecting member 8 has a yoke gap 29 surrounded by the upper wall 27 of the drive-side connecting piece 24, the motor-side connecting piece 25, and adjacent connecting pieces 26. The yoke gap 29 opens outwards radially to the outside of the drive-side connecting piece 24 and radially to the outside of the motor-side connecting piece 25. A yoke piece 16 is disposed in the yoke gap 29. Furthermore, in this embodiment, the connecting member 8 is integrally formed from a suitable material.

[0033] like Figure 2 as well as Figure 4 As shown, the connecting member 8 connects the drive unit and the coil 4 through the gap 23. At this time, with the connecting piece 26 of the connecting member 8 penetrating the gap 23, the drive unit-side connecting piece 24 is located on the upper side J12 of the second connecting yoke 7, and the motor-side connecting piece 25 is located within the gap 9 on the lower side J11 of the second connecting yoke 7. The coil 4 is provided at the end of the lower side J11 of the motor-side connecting piece 25, extending downwards towards J11. The coil 4, supported by the motor-side connecting piece 25, is positioned between the outer yoke 3 and the magnet 5 provided on the inner yoke 2.

[0034] This voice coil motor 1, with its structure, allows the coil 4 to move along the axial direction J1 by energizing the coil 4. The movement of the coil 4 along the axial direction J1 causes the connecting member 8, which supports the coil 4, to move along the axial direction J1 as well. Therefore, the voice coil motor 1 can drive the drive unit connected to the connecting member 8.

[0035] Next, use Figure 5 and Figure 6 The manufacturing process of the voice coil motor 1 according to this embodiment will be described. To manufacture the voice coil motor 1, firstly, the outer yoke 3 and the inner yoke 2 are fixed to the first connecting yoke 6, and the magnet 5 is fixed to the inner yoke 2. In the example shown, the outer side of the radial direction K1 of the magnet 5 is the N pole, and the inner side of the radial direction K1 of the magnet 5 is the S pole. Next, the yoke piece 16 is inserted from the outer side of the radial direction K1 into the yoke gap 29 of the connecting member 8, which supports the coil 4. The yoke piece 16 is temporarily fixed to the connecting member 8 with the yoke piece 16 inserted into the yoke gap 29. With the yoke piece 16 inserted into the yoke gap 29, the coil 4 supported on the connecting member 8 is inserted into the gap 9 from the opening of the upper side J12. After the coil 4 is inserted into the gap 9, the yoke piece 16 is fixed to the inner yoke 2 and the outer yoke 3. With the yoke 16 fixed to the inner yoke 2 and the outer yoke 3, the inner yoke 2 passes through the through hole 28 of the connecting member 8. Furthermore, when the yoke 16 is temporarily fixed to the connecting member 8, the preferred positional relationship between the yoke 16 and the outer yoke 3 is such that when the connecting member 8 is moved downwards J11, the end face 22 of the yoke 16 contacts the inner circumferential surface 10 of the outer yoke 3. This manufactures the voice coil motor 1 of this embodiment.

[0036] In the case of the voice coil motor 1 in this embodiment, the voice coil motor 1 has a first connecting yoke 6 and a second connecting yoke 7. Therefore, as Figure 4 As shown, in the voice coil motor 1, the magnetic circuit 30 is formed by the inner yoke 2, the outer yoke 3, and the first connecting yoke 6, and the magnetic circuit 31 is formed by the inner yoke 2, the outer yoke 3, and the second connecting yoke 7. Therefore, the voice coil motor 1 according to this embodiment can increase the thrust of the coil 4. In addition, in the case of the voice coil motor 1 of this embodiment, the second connecting yoke 7 is mounted on the inner yoke 2 and the outer yoke 3. Therefore, in the voice coil motor 1 according to this embodiment, since it is not necessary for the connecting member 8 to pass through the second connecting yoke 7 which is mounted on the inner yoke 2 and the outer yoke 3, the design freedom of the connecting member 8 can be increased.

[0037] In the case of the voice coil motor 1 of this embodiment, since the yoke 16 is roughly fan-shaped when viewed from above, the circumferential length of the end of the yoke 16 located on the outer yoke 3 side is greater than the circumferential length of the end of the yoke 16 located on the inner yoke 2 side. Therefore, according to the voice coil motor 1 of this embodiment, the largest circumferential length of the gap 23 is less than the radial length of the gap 23, thus suppressing the obstruction of magnetic flux flow by the gap 23 and ensuring the cross-sectional area of ​​the gap 23. By ensuring the cross-sectional area of ​​the gap 23, the connecting piece 26 of the connecting member 8 can be made thicker, thus enhancing the strength of the connecting member 8.

[0038] In the case of the voice coil motor 1 of this embodiment, the connecting member 8 is integrally formed. Therefore, according to the voice coil motor 1 of this embodiment, the rigidity of the connecting member 8, which is a component on the moving side, can be improved. As a result, the swaying of the connecting member 8 during movement can be suppressed, thereby improving the performance of the voice coil motor 1. In addition, in the case of the voice coil motor 1 of this embodiment, the connecting member 8 has a yoke gap 29 for inserting the yoke plate 16. As a result, when manufacturing the voice coil motor 1, the yoke plate 16 can be installed on the inner yoke 2 and the outer yoke 3 with the yoke plate 16 inserted into the yoke gap 29. Therefore, the voice coil motor 1 of this embodiment can ensure the assemblability of the voice coil motor 1.

[0039] According to the embodiment described above, the voice coil motor 1 includes a first connecting yoke 6 and a second connecting yoke 7. The second connecting yoke 7 has a plurality of yoke plates 16 that are independent of the inner yoke 2 and the outer yoke 3, and gaps 23 are provided between adjacent yoke plates 16. Therefore, a voice coil motor 1 that can increase the degree of design freedom while achieving an increase in thrust can be provided.

[0040] This disclosure has been described in detail, but it is not limited to the embodiments described above. Various additions, substitutions, modifications, and partial deletions can be made to these embodiments without departing from the spirit of this disclosure, or from the spirit of this disclosure derived from the claims and their equivalents. In the embodiments described above, the order of each action and the order of each process are shown as examples and are not limited thereto. The same applies to the use of numerical values ​​or formulas in the description of the embodiments described above.

[0041] For example, such as Figure 7 As shown in Modification 1, the magnet 5 can also be provided on the outer yoke 3. Furthermore, structural components with the same reference numerals as those indicated in the above embodiments are sometimes omitted from description below since they function the same way.

[0042] In the case of the voice coil motor 1a of this modified example 1, the inner diameter of the cylindrical magnet 5 is larger than the outer diameter of the coil 4. For example... Figure 7 As shown, magnet 5 is fixed to outer yoke 3 with its outer peripheral surface 32 in contact with the inner peripheral surface 10 of outer yoke 3. In the example shown, the outer side of radial K1 of magnet 5 is the N pole, and the inner side of radial K1 of magnet 5 is the S pole. With magnet 5 fixed to outer yoke 3, coil 4 located in gap 9 is surrounded by magnet 5. That is, coil 4 is positioned between magnet 5 fixed to outer yoke 3 and inner yoke 2. Thus, magnet 5 is positioned outside coil 4 in contact with outer yoke 3.

[0043] Alternatively, magnet 5 and inner yoke 2 can also be Figure 8 The structure of Modified Example 2 is shown. Furthermore, structural components with the same reference numerals as those indicated in the above embodiments are sometimes omitted from description below since their functions are the same.

[0044] In the case of the voice coil motor 1b of this modified example 2, the magnet 5 is cylindrical. In the example shown, the magnet 5 is cylindrical with its axial direction J1 along the vertical direction. The magnet 5 is fixed to the first connecting yoke 6. Specifically, the magnet 5 is fixed to the first connecting yoke 6 with its lower side J11 surface 33 in contact with the upper side J12 plate surface 15 of the first connecting yoke 6. While fixed to the first connecting yoke 6, the magnet 5 extends upward from the first connecting yoke 6 to the upper side J12. While fixed to the first connecting yoke 6, the magnet 5 is arranged on the same axis as the outer yoke 3. Furthermore, the upper side J12 portion of the magnet 5 is the N pole, and the lower side J11 portion of the magnet 5 is the S pole.

[0045] In the case of the voice coil motor 1b in this modified example 2, the inner yoke 2 is cylindrical. In the example shown, the inner yoke 2 is cylindrical with its axial direction J1 along the vertical direction. The inner yoke 2 is fixed to the first connecting yoke 6 via the magnet 5. Specifically, the inner yoke 2 is fixed to the magnet 5 with its lower surface J11 13 in contact with the upper surface J12 34 of the magnet 5. With the inner yoke 2 fixed to the first connecting yoke 6, it is arranged on the same axis as the magnet 5 and the outer yoke 3.

[0046] The diameters of the inner yoke 2 and the magnet 5 are smaller than the inner diameter of the outer yoke 3. Therefore, a continuous cylindrical gap 9 in the vertical direction is formed between the inner yoke 2 and the outer yoke 3, and between the magnet 5 and the outer yoke 3. A coil 4, supported by the connecting member 8, is disposed within this gap 9. The coil 4, the inner yoke 2, and the outer yoke 3 are arranged on the same axis.

[0047] Furthermore, in the above embodiments, the second connecting yoke 7 of the first connecting yoke 6 and the second connecting yoke 7 has a plurality of yoke pieces 16. However, it is also possible that the first connecting yoke 6 of the first connecting yoke 6 and the second connecting yoke 7 has a plurality of yoke pieces 16, or that both the first connecting yoke 6 and the second connecting yoke 7 have a plurality of yoke pieces 16 arranged in a cylindrical shape to connect the inner yoke 2 and the outer yoke 3.

[0048] Furthermore, in the above embodiment, the gap 23 is formed in a roughly fan shape when viewed from above, but it is not limited to this; for example, it could also be rectangular or circular when viewed from above. In this case, the inner yoke 2, the outer yoke 3, and the yoke plate 16 have appropriate shapes.

[0049] Regarding the above-described embodiments, the following notes are further disclosed.

[0050] (Note 1)

[0051] The voice coil motor (1) comprises: a cylindrical or cylindrical inner yoke (2); an outer yoke (3) which is cylindrical and surrounds the inner yoke (2) in such a way that a cylindrical gap (9) is formed between the inner yoke (2) and the outer yoke (3); a cylindrical coil (4) disposed in the gap (9); a magnet (5) disposed inside the coil (4) in contact with the inner yoke (2) or outside the coil (4) in contact with the outer yoke (3); a first connecting yoke (6) that connects one end of the axial direction (J1) of the inner yoke (2) to one end of the axial direction (J1) of the outer yoke (3); and a second connecting yoke (7) that connects the other end of the axial direction (J1) of the inner yoke (2) to the other end of the axial direction (J1) of the outer yoke (3). At least one of the first connecting yoke (6) and the second connecting yoke (7) has a plurality of yoke plates (16) arranged in a cylindrical shape to connect the inner yoke (2) and the outer yoke (3). The plurality of yoke plates (16) are constructed of independent components relative to the inner yoke (2) and the outer yoke (3) in such a way as to be mounted on the inner yoke (2) and the outer yoke (3). A gap (23) is provided between adjacent yoke plates (16, 16) for taking out the output of the voice coil motor (1).

[0052] (Note 2)

[0053] Based on Appendix 1, the voice coil motor (1) preferably has a larger circumferential length at the end of the magnetic yoke (16) located on the outer magnetic yoke (3) side than the circumferential length at the end of the magnetic yoke (16) located on the inner magnetic yoke (2) side.

[0054] (Note 3)

[0055] Based on Appendix 1 or 2, the voice coil motor 1 preferably has the end face (22) of the magnetic yoke (16) on the side of the outer magnetic yoke (3) in contact with the inner circumferential surface (10) of the outer magnetic yoke (3), and the end face (21) of the magnetic yoke on the side of the inner magnetic yoke (2) in contact with the outer circumferential surface (11) of the inner magnetic yoke (2).

[0056] (Note 4)

[0057] Based on any one of Appendix 1 to 3, the voice coil motor (1) preferably has a connecting member (8) that connects the drive unit driven by the output of the voice coil motor (1) to the coil (4) in a state that passes through the gap (23). The connecting member (8) has a yoke gap (29) for arranging the yoke plate (16) and is integrally formed.

[0058] Explanation of reference numerals in the attached figures

[0059] 1: Voice coil motor; 2: Inner yoke; 3: Outer yoke; 4: Coil; 5: Magnet; 6: First connecting yoke; 7: Second connecting yoke; 8: Connecting component; 9: Gap; 10: Inner circumferential surface of the outer yoke; 11: Outer circumferential surface of the inner yoke; 16: Yoke plate; 21: End face of the yoke plate; 22: End face of the yoke plate; 23: Gap; 29: Gap for the yoke.

Claims

1. A voice coil motor, comprising: Inner magnetic yoke in the form of a cylinder or column; The outer magnetic yoke is cylindrical and surrounds the inner magnetic yoke in such a way that it forms a cylindrical gap with the inner magnetic yoke; A cylindrical coil disposed in the gap; A magnet is disposed inside the coil in contact with the inner yoke, or outside the coil in contact with the outer yoke. A first connecting yoke connects one axial end of the inner yoke to one axial end of the outer yoke; and The second connecting yoke connects the other end of the inner yoke along its axial direction to the other end of the outer yoke along its axial direction, wherein... At least one of the first connecting yoke and the second connecting yoke has a plurality of yoke plates arranged in a cylindrical shape to connect the inner yoke and the outer yoke. The plurality of magnetic yoke plates are composed of components independent of the inner and outer magnetic yokes, mounted on the inner and outer magnetic yokes respectively. A gap is provided between adjacent magnetic yoke plates to extract the output of the voice coil motor.

2. The voice coil motor according to claim 1, wherein, The circumferential length of the end of the magnetic yoke located on the outer magnetic yoke side is greater than the circumferential length of the end of the magnetic yoke located on the inner magnetic yoke side.

3. The voice coil motor according to claim 1 or 2, wherein, The end face of the magnetic yoke located on the outer magnetic yoke side is brought into contact with the inner circumferential surface of the outer magnetic yoke, and the end face of the magnetic yoke located on the inner magnetic yoke side is brought into contact with the outer circumferential surface of the inner magnetic yoke.

4. The voice coil motor according to any one of claims 1 to 3, wherein, The voice coil motor includes a connecting member that connects the drive unit driven by the output of the voice coil motor to the coil in a manner that extends through the gap. The connecting component has a yoke-specific gap for arranging the yoke sheet and is integrally formed.

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