Lens driving device, camera device, and electronic device

Abstract

The present invention provides a lens driving device, a camera device, and an electronic device, which can obtain stable driving characteristics. A lens driving device (10) includes a fixed body (12) having a base (64), a movable body (14) having a lens support body (16) that supports a lens, a driving mechanism that drives the movable body (14) relative to the fixed body (12), the base (64) has a base body, a support plate made of metal provided on the base body, the support plate forms a support pillar portion (76) that stands up in the direction of the optical axis of the lens, and at least one component that constitutes the driving mechanism is supported by the support pillar portion (76).

Description

Technical Field

[0001] This invention relates to lens driving devices, photographic devices, and electronic devices. Background Technology

[0002] Small photographic devices are mounted on electronic devices such as mobile phones or smartphones. These small cameras are known to have lens driving mechanisms, such as those shown in Patent Document 1, which have an autofocus function. The autofocus function is achieved by driving a movable body, which has a lens support, toward a fixed base. The lens driving mechanism includes a drive mechanism to drive the movable body toward the base. [Existing Technical Documents] [Patent Documents]

[0003] [Patent Document 1] Specification of Chinese Utility Model No. CN210742590U. [Summary of the Invention] [The technical problem this invention aims to solve]

[0004] For the drive mechanism that has been used in the past, a support column is erected in the optical axis direction. The support column is integrally formed of resin with the base at the four corners of the base, and a substrate is mounted on the support column. Components constituting the drive mechanism, such as coils, are fixed on the substrate. Magnets are placed on the mounting side facing the coils.

[0005] However, this approach has a problem: the components constituting the drive mechanism are supported by resin pillars that stand upright as an integral part of the base. As a result, due to the shrinkage during the molding of the base, the pillars may deform or collapse, and the positional relationship between the components of the drive mechanism changes compared to the original design, making it impossible to obtain stable drive characteristics.

[0006] The present invention aims to solve the aforementioned problems and provide a lens driving device, photographic device, and electronic device that can obtain stable driving characteristics. [Technical Solution]

[0007] One embodiment of the present invention is a lens driving device, which includes a fixed body having a base, a movable body having a lens support body for supporting a lens, and a driving mechanism for driving the movable body relative to the fixed body. The base has a base body and a metal support plate disposed on the base body. The support plate forms a support column that stands upright in the direction of the optical axis of the lens. At least one component constituting the driving mechanism is supported by the support column.

[0008] Preferably, at least one component constituting the driving device is fixed to a flexible printed substrate, which is fixed to the support column. Furthermore, preferably, at least one component constituting the driving mechanism is a coil or a position detection element. Furthermore, preferably, the base is quadrangular when viewed from the optical axis of the lens, the support columns are located at the four corners of the base, and the flexible printed substrate is bent at the support columns. Furthermore, preferably, at least one component constituting the driving mechanism is a coil, a magnet, or a position detection element. Furthermore, preferably, the support column is formed by bending the support plate. Furthermore, preferably, the lens support has a guide shaft that guides the lens to move in the optical axis direction, and the guide shaft is fixed to the support plate. Further, preferably, the support plate is embedded in the base body.

[0009] Another embodiment of the invention is a photographic apparatus having the lens driving device and a lens supported by the lens support.

[0010] Another embodiment of the invention is an electronic device having the photographic apparatus described above. [Invention Effects]

[0011] According to the present invention, at least one component constituting the drive mechanism is supported by a metal support column provided on the base, thereby improving the positional accuracy of the component constituting the drive mechanism and providing a lens drive device, photographic device, and electronic device with stable drive characteristics. [Attached Image Description]

[0012]

【 Figure 1 [This is a perspective view of the lens driving device according to an embodiment of the present invention, viewed from an oblique top.]

【 Figure 2 [This is a perspective view of the lens device according to an embodiment of the present invention, viewed from a slightly lower angle.]

【 Figure 3 This is an exploded perspective view taken from an oblique top after the lens driving device according to an embodiment of the present invention has been disassembled from its fixed body and movable body.

【 Figure 4 This is an exploded perspective view taken from an oblique angle after all components of the lens driving device according to an embodiment of the present invention have been disassembled.

【 Figure 5 This is an exploded perspective view taken from below after all components of the lens driving device according to an embodiment of the present invention have been disassembled.

【 Figure 6 This is an exploded perspective view taken from above after the fixture used in the lens driving device according to an embodiment of the present invention has been disassembled into a base and a flexible printed substrate.

【 Figure 7This is an exploded perspective view of the fixture used in the lens driving device according to an embodiment of the present invention, viewed from an oblique angle.

【 Figure 8 This is an exploded perspective view taken from an oblique angle after disassembling the base used in the lens driving device according to an embodiment of the present invention into the base body and the support plate.

【 Figure 9 [This is a plan view showing a portion of the lens driving device according to an embodiment of the present invention.]

Figure 10

Figure 11

[0013] The embodiments of the present invention will be described below with reference to the drawings.

[0014] exist Figures 1 to 5 The image shows a lens driving device 10 according to an embodiment of the present invention. The lens driving device 10, together with the lens, is used in a camera device mounted on an electronic device such as a smartphone.

[0015] The lens driving device 10 includes a fixed body 12 and a movable body 14 that is supported and freely movable relative to the fixed body 12. The movable body 14 is as follows: Figure 4 as well as Figure 5 As shown, the device includes a lens support 16 (not shown) supporting a lens, and a first frame 18 surrounding the lens support 16. Viewed from above, the lens support 16 and the first frame 18 are generally square in shape. Furthermore, for convenience, the instruction manual defines the optical axis of the lens as the Z direction, the direction orthogonal to the optical axis as the X direction, and the direction orthogonal to both the Z and X directions as the Y direction. Also, the side of the optical axis facing the subject is defined as the top, and the side opposite to it where the image sensor (not shown) is located is defined as the bottom.

[0016] A lens mounting hole 20, which is circular when viewed from the Z direction, is formed on the inner side of the lens support 16, and a lens is mounted on the lens mounting hole 20.

[0017] The first frame 18 is composed of a first movable plate 22, a second movable plate 24, and a first cover 26. The lens support 16, the first movable plate 22, and the second movable plate 24 are made of engineering plastics such as liquid crystal polymer (LCP), polyacetal, polyamide, polycarbonate, modified polyphenylene ether, and polybutylene terephthalate. Furthermore, the first cover 26 is made of, for example, metal. Through-holes 28, 30, and 32 for light transmission are formed on the first movable plate 22, the second movable plate 24, and the first cover 26, respectively. The through-holes 28, 30, and 32 are generally circular.

[0018] The first frame 18 supports the lens support 16, allowing it to move freely in the Y and X directions. That is, the first frame 18 has an orthogonal support mechanism 34, through which the lens support 16 can move freely in the XY directions.

[0019] The orthogonal support mechanism 34 is composed of a first support mechanism 36 and a second support mechanism 38 spaced apart in the Z direction. The first support mechanism 36 is located below in the Z direction and consists of a first support portion 40 protruding in the Z direction from the lower part of the first movable body plate 22 and a first guide portion 42 recessed in the Z direction from the upper part of the second movable body plate 24. The first support portion 40 is fitted into the first guide portion 42. The first support portion 40 and the first guide portion 42 extend in the X direction and are formed near the four corners of the first movable body plate 22 and the second movable body plate 24. The first support portion 40 and the first guide portion 42 extending in the X direction are fitted together, restricting movement in the Y direction, so the first movable body plate 22 can only move freely relative to the second movable body plate 24 in the X direction.

[0020] The second support mechanism 38 is disposed above in the Z direction and consists of a second support portion 44 protruding in the +Z direction from the upper surface of the first movable plate 22 and a second guide portion 46 recessed in the +Z direction from the lower surface of the lens support 16. The second support portion 44 is embedded in the second guide portion 46. The second support portion 44 and the second guide portion 46 extend in the Y direction and are formed near the four corners of the lens support 16 and the first movable plate 22. The second support portion 44 and the second guide portion 46 extending in the Y direction are fitted together, restricting movement in the X direction, so the lens support 16 can only move freely relative to the first movable plate 22 in the Y direction.

[0021] Mounting portions 48 are provided at the four corners of the first cover 26, extending downward in the Z direction. Mounting holes 50 in a square shape are formed on these mounting portions 48. Furthermore, mounting portions 52 are formed at the four corners of the second movable body plate 24, protruding laterally. These mounting portions 52 are inserted into the mounting holes 50, and the first cover 26 is fixed to the second movable body plate 24.

[0022] On the outer side of the lens support 16, a first magnet 54 and a first yoke 56 are fixed on the +X and -Y direction surfaces. The first magnet 54 on the +X direction surface forms an S-pole and an N-pole in the X direction. Moreover, the first magnet 54 on the -Y direction surface forms an S-pole and an N-pole in the Y direction.

[0023] Furthermore, a second magnet 58 and a second yoke 60 are fixed to the +Y direction surface of the second movable body plate 24. The second magnet 58 is divided into two parts in the Z direction, forming an S-pole and an N-pole in the Y direction, with opposite polarities. A magnetic component 86 is fixed to the bottom surface of the second movable body plate 24, corresponding to the area below the first magnet 54. Thus, the lens support 16 and the first movable body plate 22 are attracted together by the second movable body plate 24, unifying the movable body 14 into a single component.

[0024] The relationship between the fixed body 12 and the movable body 14 will now be explained. The fixed body 12 has a second frame body 62. This second frame body 62 surrounds the first frame body 18 of the movable body 14. The second frame body 62 has a base 64 and a second cover 66 mounted on the base 64. The base 64 and the second cover 66 are quadrangular in shape when viewed from above, with the second cover 66 embedded in the outside of the base 64 to form the second frame body 62. Furthermore, through holes 72 and 74 are formed on the bottom surface 68 of the base 64 and the upper surface 70 of the second cover 66 to allow light to pass through or be inserted into a lens.

[0025] Furthermore, at the four corners of the base 64, support pillars 76 are formed, rising upwards from the bottom portion 68, clamping and dividing the corners into two parts. To enclose these support pillars 76, a flexible printed circuit board 78 is disposed on the outside of the base 64. The flexible printed circuit board 78 is bent into a four-cornered shape and fixed to the support pillars 76, enclosing the shape of the base 64, with a terminal portion 80 formed at its lower part. Through this terminal portion 80, energizing the first coil 82 and the second coil 84, described later, is restricted, but the process is not limited thereto.

[0026] A first coil 82 is fixed to the inner side of the flexible printing substrate 78 in the +X and -Y directions. A second coil 84 is fixed to the inner side of the flexible printing substrate 78 in the +Y direction. The first coil 82 faces the first magnet 54. The second coil 84 faces the second magnet 58. Furthermore, a position detection element 124 for detecting the position of the moving body 14 is provided within the first coil 82. Furthermore, in this embodiment, a coil and a position detection element are provided on the fixed body 12 side, and a magnet is provided on the moving body 14 side. However, it is also possible to provide a magnet on the fixed body 12 side and a coil and a position detection element on the moving body 14 side.

[0027] Furthermore, a magnetic component 86 composed of magnetic materials is provided on the outer side of the +Y direction portion of the flexible printed substrate 78. This magnetic component 86 clamps the flexible printed substrate 78 and faces the second coil 84 and the second magnet 58. Magnetic flux from the second magnet 58 flows through the magnetic component 86, thus generating an attractive force between the second magnet 58 and the magnetic component 86. Therefore, along the fixed body 12, the attractive force acts in the +Y direction on the moving body 14.

[0028] The movable body 14 is supported by the optical axis direction support mechanism 88 and can move freely in the Z direction relative to the fixed body 12. The optical axis direction support mechanism 88 is composed of a main guide shaft 90 provided on the base 64, a second guide shaft 92, a guide hole 114 and a guide wall 116 provided on the movable body 14.

[0029] The main guide shaft 90 and the secondary guide shaft 92 are made of metal and, in this embodiment, form cylinders extending in the Z direction. Furthermore, the cross-sections of the main guide shaft 90 and the secondary guide shaft 92 in the XY direction are circular, but they can also be part of a circle, or in addition to a circle, they can be elliptical or polygonal.

[0030] Regarding the primary guide shaft 90 and the secondary guide shaft 92, the lower end of the primary guide shaft 90 is fixed near the -X+Y direction end of the bottom surface 68 of the base 64, and the lower end of the secondary guide shaft 92 is fixed near both ends of the +X+Y direction of the bottom surface 68 of the base 64. Moreover, they are parallel to the Z direction and stand upright.

[0031] like Figures 6 to 8 As shown, the base 64 consists of a base body 98 and a metal support plate 100 embedded in the base body 98 at the bottom surface 68 of the base 64. The base body 98 is made of resin. The base 64 is insert-molded, so that the entire periphery of the support plate 100 is embedded in the base body 98. On the support plate 100, the support column 76 is integrally formed and protrudes upward from the base body 98.

[0032] The flexible printed circuit board 78 mates with three sides of the base 64 and is bent. The flexible printed circuit board 78 is connected to the support pillars 76 at the four corners of the base 64. Furthermore, positioning holes 126 are formed near the corners of the flexible printed circuit board 78, and positioning protrusions 128 protruding outwards are formed on the support pillars 76. The positioning protrusions 128 are inserted into the positioning holes 126 to position the flexible printed circuit board 78. Additionally, cutouts 130 cut in the -Z direction are formed below the three corners of the flexible printed circuit board 78. Segments 132 protruding in the +Z direction are formed at the four corners of the base body 98. The cutouts 130 are inserted into the segments 132. The flexible printed circuit board 78, while positioned relative to the base 64, is fixed to the support pillars 76 using adhesives or the like.

[0033] like Figures 9 to 12 As shown, the main guide shaft 90 and the secondary guide shaft 92 are integrally formed, and from top to bottom, they are a guide shaft body portion 102, a flange portion 104, and an insertion portion 106, respectively. The insertion portion 106 is formed at the lower end of the main guide shaft 90 and the secondary guide shaft 92, and the flange portion 104 is formed directly above the insertion portion 106. In order to make the insertion portion 106 easy to stabilize during assembly, its size is larger than that of the guide shaft body portion 102, and the flange portion 104 is larger than that of both the guide shaft body portion 102 and the insertion portion 106.

[0034] On the other hand, a first insertion hole 108 is formed on the support plate 100 of the base 64, and a second insertion hole 110 is formed on the base body 98 to surround the first insertion hole 108.

[0035] The insertion portions 106 of the main guide shaft 90 and the secondary guide shaft 92 are inserted into the first insertion hole 108 of the support plate 100 and protrude into the second insertion hole 110 of the base body 98. Furthermore, the flange portions 104 of the main guide shaft 90 and the secondary guide shaft 92 are inserted into the second insertion hole 110 of the base body 98 and contact the support plate 100 around the first insertion hole 108 of the support plate 100.

[0036] The lower ends of the insertion portions 106 of the main guide shaft 90 and the secondary guide shaft 92 are riveted to the support plate 100 to form a riveting portion 112. Between this riveting portion 112 and the flange portion 104, the first insertion hole 108 of the support plate 100 is clamped, and the main guide shaft 90 and the secondary guide shaft 92 are fixed to the support plate 100. The riveting portion 112 can also be formed by conventional stamping, but to reduce the pressure impact on other parts, it can also be formed by a method called high-speed rotation or rotary riveting. High-speed rotation or rotary riveting refers to a processing method in which the tip of the workpiece is crushed using a rotating tool.

[0037] The main guide shaft 90 is inserted into a guide hole 114 formed in the second moving body plate 24. This guide hole 114 is divided into an upper portion and a lower portion, and the main guide shaft 90 contacts both the upper and lower portions of the guide hole 114. Furthermore, the guide hole 114 forms a V-shape extending from the Z direction towards the +Y direction when viewed from the Z direction. As previously described, the moving body 12 is attracted to the +Y direction by the magnetic component 86 and the second magnet 58, thus the main guide shaft 90 contacts the V-shaped end face of the guide hole 114, ensuring a sliding position.

[0038] The secondary guide shaft 92 is sandwiched between two guide walls 116 formed on the second moving body plate 24. The two guide walls 116 form parallel surfaces in the X direction. The guide walls 116 protrude from each other in a planar or curved shape, such that the central portion of the guide wall 116 in the Z direction contacts the secondary guide shaft 92 from the +Y and -Y sides. Therefore, the secondary guide shaft 92 guides the moving body 14 while contacting the protruding portion of the guide wall 116.

[0039] Furthermore, the secondary guide shaft 92 is shorter in the Z direction than the primary guide shaft 90. For example... Figure 12 As shown, the two guide walls 116 are connected at the upper part by an upper connecting portion 118. In this embodiment, the formation of the upper connecting portion 118 completely closes the upper open portion of the guide wall 116. Moreover, at the lower part of the guide wall 116, except for the portion where the secondary guide shaft 92 is inserted, the guide wall 116 is connected around its perimeter by a lower connecting portion 120, and the guide wall 116 becomes box-shaped through the upper connecting portion 118 and the lower connecting portion 120. As a result, the guide wall 116 forms a box shape, thus increasing the strength of the guide wall 116.

[0040] Moreover, such as Figure 10 as well as Figure 11 As shown, the height at which the guide wall 116 contacts the secondary guide shaft 92 is between the heights of the two guide holes 114. Therefore, the upper end of the guide wall 116 that contacts the secondary guide shaft 92 is often lower than the upper end of the upper guide hole 114, which allows the secondary guide shaft 92 to be shorter than the main guide shaft 90 to some extent. Thus, an upper connecting portion 118 can be provided to cover the upper side of the secondary guide shaft 92.

[0041] In this structure, if the first magnet 54 on the X-direction surface is energized and the first coil 82 facing it is energized, a Lorentz force in the X-direction is generated on the first coil 82. The first coil 82 is fixed on the base 64, so the reaction force generated on the first magnet 54 becomes a driving force relative to the lens support 16 and the first movable plate 22, which are supported by the first support mechanism 36 and moved in the X-direction.

[0042] Furthermore, if the first coil 82 facing the first magnet 54 in the Y direction is energized, a Lorentz force in the Y direction is generated on the first coil 82. The first coil 82 is fixed on the base 64, so the reaction force generated on the first magnet 54 becomes a driving force relative to the lens support 16, which is supported by the second support mechanism 38 and moves in the Y direction.

[0043] After the lens support 16 moves to at least one side in the X or Y direction, if the energization of the first coil 82 is stopped, the lens support 16 stops at the position where the energization is stopped due to the attraction between the first magnet 54 and the magnetic component 86 and the friction between the first support 40 and the first guide 42, and between the second support 44 and the second guide 46.

[0044] Subsequently, if the second coil 84, which is positioned between the second magnet 58 and the magnetic component 86, is energized, a Lorentz force in the Z direction is generated on the second coil 84. The second coil 84 is fixed on the base 64, so the reaction force generated on the second magnet 58 becomes a driving force relative to the moving body 14, which is supported by the optical axis support mechanism 88 and moves in the Z direction.

[0045] After the moving body 14 moves to the Z direction, if the energization of the second coil 84 is stopped, the moving body 14 will stop at the position where the energization is stopped due to the attraction between the second magnet 58 and the magnetic component 86, as well as the friction between the main guide shaft 90 and the guide hole 114, and between the secondary guide shaft 92 and the guide wall 116. The position of the moving body 14 in the XY direction can be detected by the position detection element 124.

[0046] The first coil 82, the second coil 84, and the position detection element 124 are fixed on the flexible printing substrate 78. However, the flexible printing substrate 78 is fixed on the support column 76, which is integrally formed with the metal support plate 100. Therefore, the tilt and positional offset of the first coil 82, the second coil 84, and the position detection element 124 relative to the first magnet 82 and the second magnet 84 can be reduced. As a result, the position of the moving body 14 can be precisely controlled.

[0047] Furthermore, the movable body 14 is supported and guided on one side in the Y direction by the main guide shaft 90 and the secondary guide shaft 92. The main guide shaft 90 and the secondary guide shaft 92 are riveted together by the riveting part 106 and firmly fixed to the metal support plate 100, so that its tilt can be controlled even if the upper end is not fixed.

[0048] Furthermore, the guide walls 116, 116 of the guide shaft 92 are connected by the upper connecting part 118 and the lower connecting part 120, thus increasing the strength of the guide walls 116, 116. Even if the moving body 14 is subjected to impact due to falling or other reasons, the displacement and tilting changes during the movement can be reduced.

[0049] Furthermore, in this embodiment, the lens driving device has both focus adjustment and shake compensation functions; however, having only the focus adjustment function is sufficient, and therefore it can also be applied to devices with zoom functions. Moreover, this specification describes a lens driving device used in a photographic apparatus, but the present invention can also be applied to other devices. [Symbol Explanation]

[0050] 10 Lens driving device 12 Fixed body 14 Moving bodies 16 Lens support 18 First Frame 20 Lens mounting holes 22 First moving body plate 24. Second moving body plate 26 First Cover Through holes 28, 30, 32 34. Orthogonal support mechanism 36. First Supporting Organization 38. Second Supporting Organization 40 First Support Section 42 First Guiding Section 44 Second Support Section 46. ​​Second Guiding Section 48 Installation Department 50 mounting holes 52 Installed parts 54 No. 1 Magnet 56 First yoke 58 No. 2 Magnet 60 Second yoke 62. Second Frame 64 abutment 66 Second Cover 68 Bottom surface 70 Upper face Through holes 72 and 74 76. Supporting Department 78 Flexible Printed Substrates 80 terminal section 82 First coil 84. Second coil 86 Magnetic components 88 Optical Axis Direction Support Mechanism 90 Dominant Directional Axis 92 Sub-guide shafts 98 Abutment body 100 support plate 102 Guide shaft body section 104 Flange section 106 Insertion section 108 First insertion hole 110 Second Insertion Hole 112 Riveting section 114 Guide Hole 116 Guide Wall 118 Upper connecting part 120 Lower connecting part 124 Position Detection Element 126 positioning holes 128 Positioning convex part 130 Incision Site Section 132

Claims

1. A lens driving device, characterized in that: include Fixture with base A movable body with a lens support for supporting the lens. The drive mechanism that drives the moving body relative to the fixed body. The base is rectangular when viewed from the optical axis of the lens, and has a base body and a metal support plate disposed on the base body, the support plate being embedded in the base body. The support plate forms a pillar portion that stands upright towards the optical axis of the lens. The pillar portion is located at the four corners of the base, and the pillar portion is formed by bending the support plate. At least one component constituting the drive mechanism is supported by the support column; At least one of the components constituting the driving device is a coil or a position detection element. The component is fixed on a flexible printed substrate. The flexible printed substrate is bent into a quadrangular shape at the support portion and fixed on the support portion, surrounding the shape of the base and forming a terminal portion at its lower part.

2. The lens driving device according to claim 1, characterized in that, It has a guide shaft that guides the lens to move in the direction of the optical axis, and the guide shaft is fixed on the support plate.

3. A photographic apparatus, characterized in that, The device comprises the lens driving device as described in claim 1 and a lens supported by the lens support.

4. An electronic device, characterized in that, The photographic apparatus has the features described in claim 3.

Images