Prism drive device, camera device, and electronic equipment

Abstract

The present invention provides a prism drive device, a camera device, and an electronic device that suppress prism tilt caused by weight. The prism drive device (3) comprises: a base (50, 50A) as a fixed portion; a movable portion having a holder (20, 20A) for holding a prism (2); and a first support shaft (81) that rotatably supports an intermediate member (30, 30A) belonging to the movable portion relative to the base (50, 50A). The base end portion (81b) of the first support shaft (81) is fixed to a metal member belonging to the base (50, 50A) by riveting or welding.

Description

Technical Field

[0001] The present invention relates to a prism driving device, a camera device, and an electronic device used in electronic devices such as smartphones. Background Art

[0002] Among the camera devices installed in electronic devices such as smartphones, there are some that include optical components such as a lens and a prism arranged on the optical path from the subject to the image sensor, and a prism drive device that tilts the prism about two orthogonal support axes. Patent Document 1 discloses technology related to such camera devices. In the prism drive device disclosed in Patent Document 1, a movable portion supporting the prism is rotatably supported about a first support axis by a support portion called a sleeve. The sleeve is rotatably supported about a second support axis orthogonal to the first support axis.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: China Publication Patent No. 107357114A. Summary of the Invention

[0006] (Problems to be solved by the invention)

[0007] However, in conventional optical member driving devices, both ends of the support shaft are inserted into the mounting holes for mounting, which causes a problem in that the prism is easily tilted due to the weight of the prism.

[0008] The present invention has been conceived in view of the above-mentioned problems, and an object of the present invention is to provide a prism driving device, a camera device, and an electronic device that suppress the tilt of a prism due to weight.

[0009] (Solutions to solve problems)

[0010] In order to solve the above-mentioned problems, a prism driving device as a preferred embodiment of the present invention is characterized in that it comprises: a fixed part; a movable part having a holding frame for holding the prism; and a first support shaft that supports the movable part so that it can rotate freely relative to the fixed part, and the base end portion of the first support shaft is fixed to the fixed part by riveting or welding.

[0011] In this embodiment, the fixing portion may be a plate-shaped metal member.

[0012] Alternatively, the plate-shaped metal member may be embedded in the resin member.

[0013] Furthermore, a normal line of the incident surface of the prism may be parallel to a normal line of the plate surface of the plate-shaped metal member and the first support axis.

[0014] Furthermore, the movable portion may include: an intermediate member mounted on the first support shaft; and a second support shaft that rotatably supports the holder relative to the intermediate member.

[0015] In addition, the incident surface and the exit surface of the prism may be orthogonal, the first support axis may be parallel to the normal line of the incident surface, and the second support axis may be orthogonal to the normal lines of the incident surface and the exit surface.

[0016] Furthermore, the base end portion may include an insertion portion having a larger diameter than the main body portion and a flange portion having a larger diameter, wherein the insertion portion is inserted and fixed in a hole formed in the fixing portion.

[0017] Furthermore, the movable portion may be pressed against the first support shaft in a direction perpendicular to the axial direction of the first support shaft by a magnetic force.

[0018] A camera device according to another preferred embodiment of the present invention includes the above-mentioned prism driving device and the prism.

[0019] As another preferred embodiment of the present invention, an electronic device includes the above-mentioned camera device.

[0020] (Effects of the Invention)

[0021] The prism drive device according to the present invention comprises: a fixed portion; a movable portion having a holder for holding a prism; and a first support shaft that rotatably supports the movable portion relative to the fixed portion, the base end of the first support shaft being fixed to the fixed portion by riveting or welding. The first support shaft is securely fixed to the fixed portion. Therefore, the movable portion supported by the first support shaft is less likely to tilt. Thus, a prism drive device, camera device, and electronic device can be provided that suppress weight-induced prism tilt. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a front view of a smartphone 9 equipped with a camera device 8 including the prism drive device 3 as the first embodiment of the present invention.

[0023] Figure 2 yes Figure 1 A three-dimensional diagram of the prism driving device 3.

[0024] Figure 3 yes Figure 2 Exploded three-dimensional diagram.

[0025] Figure 4 It will Figure 2 3 is a cross-sectional view of the prism driving device 3 cut along a plane that is orthogonal to the central axis of the first support shaft 81 and includes the central axes of the second support shafts 61 and 62.

[0026] Figure 5 It will Figure 2 3 is a cross-sectional view of the prism driving device 3 cut along a plane including the central axis of the first support shaft 81 and perpendicular to the central axes of the second support shafts 61 and 62.

[0027] Figure 6 It is an exploded perspective view of the prism driving device 3 according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0028] Hereinafter, a first embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 As shown, the camera device 8 is housed in a housing of a smartphone 9 .

[0029] The camera device 8 includes a prism 2 and a lens 6 as optical components; an image sensor 7 that performs photoelectric conversion on light guided from a photographic subject through the prism 2 and lens 6; and a prism drive device 3 that drives the prism 2. Light incident on the prism 2 from the photographic subject is bent by the prism 2, passes through the lens 6, and then enters the image sensor 7.

[0030] The following describes the structure of this embodiment, assuming an orthogonal coordinate system consisting of mutually orthogonal X-axis, Y-axis, and Z-axis. The X-axis is parallel to the optical axis of lens body 6. The Z-axis and Y-axis are mutually orthogonal and perpendicular to the X-axis. Light from the subject enters prism 2 from the Z-axis direction, is bent at a right angle by prism 2, travels along the X-axis direction, and passes through lens body 6. Hereinafter, in the X-axis direction, the side with prism 2 as viewed from lens body 6 is referred to as the -X side, and the opposite side with image sensor 7 is referred to as the +X side. Furthermore, in the Z-axis direction, the side with the subject as viewed from prism 2 is referred to as the +Z side, and the opposite side is referred to as the -Z side.

[0031] like Figure 3 As shown, the prism drive device 3 comprises a housing 10; a holder 20; an intermediate member 30; an FPC (Flexible Printed Circuit) 40; a base 50; a first support shaft 81 parallel to the Z axis; and second support shafts 61 and 62 parallel to the Y axis. The housing 10 and base 50 are the fixed portion. The holder 20, the intermediate member 30, and the second support shafts 61 and 62 are the movable portion. The first support shaft 81 is fixed to the base 50 and supports the movable portion so that it can rotate freely relative to the fixed portion. The holder 20 holds the prism 2. The intermediate member 30 is mounted on the first support shaft 81, and the second support shafts 61 and 62 are mounted on the intermediate member 30 and support the holder 20 so that it can rotate freely relative to the intermediate member 30. In the prism drive device 3, the housing 10 and base 50 are combined to form a roughly rectangular parallelepiped frame. The movable portion is housed within this frame.

[0032] like Figure 2 and Figure 3 As shown, the prism drive device 3 has a roughly rectangular parallelepiped shape with the -Z side open. The housing 10 has an open portion 12 formed by cutting away the central portion in the Y direction of the side surface 11 on the +X side across the entire Z direction; and an open portion 14 formed by cutting away the central portion in the Y direction of the top surface 13 on the +Z side, excluding a portion on the -X side. The holder 20 that holds the prism 2 is accommodated within the space formed by the housing 10 and the base 50. The incident surface 2z of the prism 2 held in the holder 20 is exposed through the +Z side opening 14 of the housing 10, while the exit surface 2x of the prism 2 is exposed through the +X side opening 12.

[0033] like Figure 3 As shown, the base 50 is formed entirely of resin and has a roughly rectangular parallelepiped shape. The base 50 has: a bottom portion 54 on the -Z side; and a side portion 51 on the -Y side and a side portion 52 on the +Y side that rise at right angles from the bottom portion 54. The +X side of the base 50 is open, and the -X side is open near the center. Moreover, the open area on the -X side of the base 50 is covered by the side portion 43 of the FPC 40 and the yoke 53. A plate-shaped metal component 55 is embedded in the bottom portion 54 by insert molding. A hole 54a is formed in the main body of the bottom portion 54, and a hole 55a smaller than the hole 54a is formed in the metal component 55 at a position corresponding to the hole 54a.

[0034] The first support shaft 81 is fixed to the metal member 55 with its axial direction parallel to the Z-axis, supporting the intermediate member 30 relative to the base 50 so that it can rotate freely about the first support shaft 81, which is parallel to the Z-axis. The first support shaft 81 includes a main body 81a and a base end 81b fixed to the metal member 55. The base end 81b is formed with an insertion portion 81c having a larger diameter than the main body 81a and a flange portion 81d having an even larger diameter. A recessed portion 81e is formed on the bottom surface of the insertion portion 81c.

[0035] The hole 54a formed in the bottom portion 54 of the base 50 has a larger diameter than the flange portion 81d, while the hole 55a formed in the metal member 55 has the same diameter as the insertion portion 81c. The base end portion 81b (i.e., the insertion portion 81c and the flange portion 81d) is inserted into the hole 54a from the +Z side, while only the insertion portion 81c is inserted into the hole 55a. The first support shaft 81 is fixed to the metal member 55 by riveting. Specifically, the mold is pressed against the recessed portion 81e, causing the insertion portion 81c to deform radially outward, thereby fixing the base end portion 81b of the first support shaft 81 to the metal member 55 of the base 50. Thus, the first support shaft 81 is firmly fixed to the base 50. Furthermore, in this first embodiment, the first support shaft 81 may be fixed to the metal member 55 of the base 50 by riveting or by welding. The yoke 125 is arranged on the −Z side of the bottom portion 54 at a position facing a magnet 113 to be described later.

[0036] The FPC 40 includes a side surface portion 43 on the -X side; side surfaces 41 and 42 bent at right angles at both ends of the side surface portion 43 in the Y-axis direction; and a bottom surface portion 44 bent at right angles on the -Z side of the side surface portion 43. Coils 91 and 92 are arranged side by side along the Y-axis on the +X side of the side surface portion 43. A Hall effect IC 101 is arranged inside the coil 91. Coil 93 is arranged on the +Z side of the bottom surface portion 44. A Hall effect IC 103 is arranged inside the coil 93. A hole 44a having a larger diameter than the flange portion 81d is formed in the bottom surface portion 44 to allow the first support shaft 81 to pass through. In the FPC 40, the bottom surface portion 44 is placed on the bottom surface portion 54 so that the hole 44a corresponds to the hole 54a. The side surfaces 41 and 42 are arranged to cover the side surfaces 51 and 52 from the outside, and the side surface portion 43 is arranged to be located inside the yoke 53.

[0037] The intermediate member 30 has a side portion 33 on the -X side, and side portions 31 and 32 on the -Y and +Y sides that bend at right angles from the side portion 33. A bearing 82 protrudes toward the +X side, extending from the -Z end toward the +Z side, at the center of the side portion 33 in the Y-axis direction. A hole with the same diameter as the main body 81a of the first support shaft 81 penetrates the bearing 82 in the Z-axis direction. The intermediate member 30 is positioned on the base 50 with the main body 81a of the first support shaft 81 inserted into the hole of the bearing 82. At this point, the -Z end face of the bearing 82 abuts the upper surface of the flange 81d. Thus, the intermediate member 30 is supported relative to the base 50 so that it can rotate freely about the first support shaft 81, which is parallel to the Z-axis.

[0038] The second support shaft 61 is fixed to the side surface 31 of the intermediate member 30, and the second support shaft 62 is fixed to the side surface 32 of the intermediate member 30. In the initial state, the center axes of the second support shafts 61 and 62 are aligned and parallel to the Y-axis. The second support shafts 61 and 62 support the retainer 20 relative to the intermediate member 30 so that the retainer 20 can rotate freely about an axis perpendicular to the plane containing the center axis of the first support shaft 81. The second support shafts 61 and 62 have main bodies 61a and 62a and flanges 61b and 62b having a larger diameter than the main bodies 61a and 62a. Support shaft fixing portions 63 and 64 are provided approximately in the center of the side surfaces 31 and 32 of the intermediate member 30. The support shaft fixing portions 63 and 64 have recessed portions 63a and 64a, the outermost circumferences of which protrude outward and receive and secure the flange portions 61b and 62b on their inner circumferences; and through-holes 63b and 64b, formed at the bottoms of the recessed portions 63a and 64a and having the same diameter as the main body portions 61a and 62a of the second support shafts 61 and 62, which extend through the side portions 31 and 32. The main body portions 61a and 62a of the second support shafts 61 and 62 are inserted from the outside into the through-holes 63b and 64b of the support shaft fixing portions 63 and 64 until the flange portions 61b and 62b abut against the recessed portions 63a and 64a, and are then secured thereto using, for example, an adhesive.

[0039] The holder 20 has an inclined portion 24 formed between the +Z-X side and the -Z+X side, which supports the reflecting surface 2s of the prism 2. A pair of magnets 111 and yokes 121, and a pair of magnets 112 and yokes 122 are arranged side by side along the Y-axis on the side surface 23 of the holder 20 on the -X side. A pair of magnets 113 and yokes 123 are arranged on the bottom surface 25 on the -Z side of the holder 20. Furthermore, the holder 20 has side surfaces 21 and 22 that sandwich the inclined portion 24 from both sides in the Y-axis direction. Bearings 71 and 72 are formed on these side surfaces 21 and 22. These bearings 71 and 72 have bottomed holes, into which second support shafts 61 and 62, respectively, protruding from the side surfaces 31 and 32 of the intermediate member 30, are inserted. This supports the holder 20 relative to the intermediate member 30 so that it can rotate freely about the second support shafts 61 and 62, which are parallel to the Y-axis. Furthermore, the second support shafts 61 and 62 are preferably arranged so that their central axes are included in the reflecting surface 2 s of the prism 2 .

[0040] A pair of magnets 111 and yoke 121, and a pair of magnets 112 and yoke 122, arranged on the holder 20, face coils 91 and 92 and yoke 53, which are arranged on the base 50 via the FPC 40. These components provide a rotational driving force to the movable portion about the first support shaft 81, which is parallel to the Z axis. In other words, the holder 20 rotates about the first support shaft 81 along with the intermediate member 30. Furthermore, the Hall effect IC 101 detects the magnetic field received from the magnets 111, thereby detecting the rotational position of the holder 20 about the first support shaft 81. This drives the coils 91 and 92 via the FPC 40 to adjust the rotational position of the holder 20 to the appropriate position.

[0041] The magnet 113 disposed on the holder 20, the coil 93, and the yoke 125 disposed on the base 50 via the FPC 40, provide a rotational driving force to the holder 20 about the second support shafts 61 and 62 parallel to the Y-axis. Furthermore, the Hall effect IC 103 detects the rotational position of the holder 20 about the second support shafts 61 and 62 by detecting the magnetic field received from the magnet 113, and supplies a driving current to the coil 93 via the FPC 40 to correct the rotational position of the holder 20 to an appropriate position.

[0042] Magnets 111 and 112 are magnetically attracted to yokes 121 and 122, pressing the +X-side portion of intermediate member 30 within bearing 82 against first support shaft 81 in the -X direction, which is perpendicular to first support shaft 81. At this point, first support shaft 81 is securely fixed to metal member 55, making it less susceptible to tilting due to the weight of the movable portion, including prism 2. This prevents tilting of prism 2 due to its weight. Furthermore, magnet 113 is attracted to yoke 125, pressing the movable portion against the fixed portion in the -Z direction. This prevents axial movement of the movable portion along the first support shaft 81.

[0043] use Figure 6 The prism drive device 3A according to the second embodiment of the present invention will now be described. The base 50A of the prism drive device 3A is formed by bending a plate-shaped metal member and has a bottom portion 54A on the -Z side, a side portion 53A rising on the -X side, and a side portion 56A rising on the +X side. A through hole is provided in the center of the side portion 56A. A hole similar to the hole 55a is provided in the bottom portion 54A (not shown). The first support shaft 81 is the same as the first support shaft 81 of the first embodiment and is inserted into the hole in the bottom portion 54A and fixed to the bottom portion 54A by riveting or welding. A magnetic yoke (not shown) is fixed to the -X side surface of the side portion 53A and the -Z side surface of the bottom portion 54A.

[0044] The FPC 40A has a side surface 43A and a bottom surface 44A, and is positioned on the +X side of the side surface 53A and the +Z side of the bottom surface 54A. As in the first embodiment, the side surface 43A is provided with coils 91 and 92 and a Hall effect IC 101, while the bottom surface 44A is provided with a coil 93 and a Hall effect IC 103. The bottom surface 44A has a hole 44Aa for inserting the first support shaft 81.

[0045] The intermediate member 30A is formed by bending a plate-shaped metal member to form side portions 31A, 32A and a bottom portion 34A. Furthermore, a bearing 82A made of resin is fixed to the bottom portion 34A. The first support shaft 81 is inserted into the bearing 82A. Spherical portions 61Aa, 62Aa are fixed to the side portions 31A, 32A so as to face each other.

[0046] The holder 20 holds the prism 2. Magnets (not shown) are fixed to the side surfaces on the -X side and the bottom surface on the -Z side of the holder 20, facing the coils 91, 92, and 93, respectively, and further facing the yoke. Flat springs 61Ab and 62Ab having concave spherical portions are fixed to the side surfaces on the ±Y sides of the holder 20. The second support shafts 61A and 62A are formed by combining the spherical portion 61Aa with the concave spherical portion of the flat spring 61Ab, and the spherical portion 62Aa with the concave spherical portion of the flat spring 62Ab. The housing 10A is fixed to the base 50A from the +Z side.

[0047] The first support shaft 81 supports the movable portion relative to the fixed portion so that it can rotate freely about the first support shaft 81. The base end of the first support shaft 81 is securely fixed to the base 50A, a metal member of the fixed portion, by riveting or welding. This reduces the risk of tilting of the movable portion, including the prism 2, due to its weight. Consequently, tilting of the prism 2 due to its weight can be suppressed.

[0048] As described above, the prism drive device 3, as one embodiment of the present invention, comprises: a base 50, 50A serving as a fixed portion; a movable portion having a holder 20, 20A for holding the prism 2; and a first support shaft 81 rotatably supporting the intermediate member 30, 30A relative to the base 50, 50A. The intermediate member 30, 30A serves as the movable portion. The base end 81b of the first support shaft 81 is fixed to a metal member serving as the base 50, 50A by riveting or welding. Thus, according to the first and second embodiments, the first support shaft 81 is securely fixed to the base 50, thereby preventing tilting caused by the weight of the prism 2.

[0049] (Description of labels)

[0050] 8 camera device; 9 smartphone; 2 prism; 2x exit surface; 2z incident surface; 2s reflection surface; 3 prism drive device; 6 lens body; 7 image sensor; 10 housing; 11, 21, 22, 23, 31, 32, 31A, 32A, 33, 41, 42, 43, 43A, 51, 52, 53A, 56A side surfaces; 25, 34A, 44, 54, 54A bottom surfaces; 44a, 54a, 55a holes; 13 top surface; 12, 14 openings; 20, 20A holder; 24 inclined portion; 30, 30A intermediate member; 40, 40 AFPC; 50, 50A base; 55 metal Components; 61, 61A, 62, 62A second support shaft; 61a, 62a main body; 61b, 62b flange; 61Aa, 62Aa spherical body; 61Ab, 62Ab leaf spring; 63, 64 support shaft fixing portion; 63a, 64a recess; 63b, 64b through-hole; 71, 72, 82, 82A bearing; 81 first support shaft; 81a main body; 81b base end; 81c insertion portion; 81d flange; 81e recess; 91, 92, 93 coil; 101, 103 Hall IC; 111, 112, 113 magnet; 53, 121, 122, 123, 125 yoke.

Claims

1. A prism driving device, characterized in that: have: a fixing portion, which is a plate-shaped metal member; a movable portion having a holder for holding a prism; and a first support shaft for rotatably supporting the movable portion relative to the plate-shaped metal member; The plate-shaped metal member is provided on the bottom portion of the base formed entirely of resin and embedded in the bottom portion. A first hole is formed in the base body portion of the bottom surface portion, and a second hole smaller than the first hole is formed in the metal member at a position corresponding to the first hole. The first support shaft includes a shaft body and a base end portion fixed to the metal member. The base end portion is formed with an insertion portion having a larger diameter than the shaft main body portion and a flange portion having a larger diameter. The diameter of the first hole is larger than that of the flange portion, while the diameter of the second hole is the same as that of the insertion portion. The base end portion, namely the insertion portion and the flange portion, is inserted into the first hole, and only the insertion portion is inserted into the second hole. The base end portion of the first support shaft is fixed to the plate-shaped metal member by caulking or welding.

2. The prism driving device according to claim 1, wherein The incident surface and the exit surface of the prism are orthogonal to each other. The normal line of the incident surface of the prism is parallel to the normal line of the plate surface of the plate-shaped metal member and the first support axis. The movable portion includes: an intermediate member having a bearing mounted on the first support shaft; and a second support shaft that rotatably supports the holder relative to the intermediate member, the second support shaft being orthogonal to the normal line of the incident surface and the normal line of the exit surface. The intermediate member of the movable portion is pressed against the first support shaft by the bearing in a direction perpendicular to the axial direction of the first support shaft, that is, in a direction normal to the emission surface of the prism, by a magnetic force. 3 . A camera device comprising the prism driving device according to claim 1 and the prism. 4 . An electronic device comprising the camera device according to claim 3 .

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