Tilt device

Abstract

A tilt device (1) comprises: a movable body (4) provided with a lens (2) and a lens frame (3); a support body (6) provided with a case (5) surrounding the movable body (4); and a gimbal mechanism (7) connecting the movable body (4) and the case (5). The gimbal mechanism (7) is provided with a gimbal frame (70), a pair of first thrust receiving members (71) that are in point contact with the gimbal frame (70) on a first axis (R1), and a pair of second thrust receiving members (72) that are in point contact with the gimbal frame (70) on a second axis (R2). The pair of first thrust receiving members (71) are disposed in the movable body (4), and the pair of second thrust receiving members (72) are disposed in the case (5). Each of the pair of second thrust receiving members (72) is provided with a first reference surface (S1) for positioning the lens frame (3) in an axial direction, and is held in the case (5) in a state in which the first reference surface (S1) is exposed toward one side (L1) in the axial direction.

Description

Tilt device

[0001] The present invention relates to a tilt device.

[0002] Conventionally, tilt devices for swinging various members have been used. Patent Document 1 describes an imaging device provided with a tilt device that swings some of the lens groups of an imaging optical system with respect to other lenses. In Patent Document 1, image blur correction and aberration correction are performed by swinging the lens about an axis orthogonal to the optical axis of the lens group.

[0003] Japanese Unexamined Patent Application Publication No. 2010-152168

[0004] In a tilt device, the positional accuracy of the object to be swung may be important. For example, in a tilt device that swings a lens, it is important to accurately align the position of the lens surface in the optical axis direction with respect to the swing center. If the distance in the optical axis direction between the swing center and the lens surface varies, the optical characteristics will change. Therefore, there is a risk that the optical performance of the imaging optical system will deteriorate. Also, if the distance in the optical axis direction between the swing center and the lens surface varies, the tilt angle of the lens surface will also vary. Therefore, when the lens to be swung is tilted significantly, there is a risk of collision with an adjacent lens.

[0005] The variation in the distance of the object to be swung (e.g., a lens) with respect to the swing center is determined by the accumulation of the dimensional tolerances of the components intervening between the component that defines the swing center and the object to be swung. When the swing center and the object to be swung are far apart, the number of intervening components increases, and the variation becomes large due to the accumulation of the dimensional tolerances of many components.

[0006] In view of such points, an object of the present invention is to improve the positional accuracy of an object to be swung, such as a lens, with respect to the swing center in a tilt device that swings the object to be swung even when the object to be swung is far from the swing center.

[0007] To solve the above problems, one embodiment of the tilt device according to the present invention comprises a movable body having an object to be swung and a holding member for holding the object to be swung, a support having a case surrounding the movable body, and a gimbal mechanism connecting the support and the movable body, wherein the central axis is defined as a straight line connecting the pivot center, which is far from the object to be swung, and the object to be swung, the axis intersecting the central axis at the pivot center is defined as the first axis, the axis intersecting the central axis and the first axis at the pivot center is defined as the second axis, the direction along the central axis is defined as the axial direction, and the side on which the object to be swung is located relative to the pivot center is defined as one side of the axial direction. The gimbal mechanism comprises a gimbal frame, a pair of first thrust bearing members that make point contact with the gimbal frame on the first axis, and a pair of second thrust bearing members that make point contact with the gimbal frame on the second axis, wherein the pair of first thrust bearing members are arranged on the movable body, and the pair of second thrust bearing members are arranged on the case, and at least one of the pair of second thrust bearing members has a first reference surface for positioning the holding member in the axial direction, and is held in the case with the first reference surface exposed toward one side in the axial direction.

[0008] Figure 1 is an external perspective view of the tilt device for oscillating the lens, and the first and second jigs used for positioning the lens. Figure 2 is an exploded perspective view of the tilt device viewed from one side in the axial direction. Figure 3 is an exploded perspective view of the tilt device viewed from the other side in the axial direction. Figure 4 is a cross-sectional view of the tilt device cut by a plane perpendicular to the axial direction. Figure 5 is a cross-sectional view of the tilt device cut by a plane containing the first axis and the central axis. Figure 6 is a cross-sectional view of the tilt device cut by a plane containing the second axis and the central axis. Figure 7 is an exploded perspective view of the gimbal frame, the first thrust bearing member, and the second thrust bearing member. Figure 8 is an exploded perspective view of the movable body viewed from one side in the axial direction. Figure 9 is an exploded perspective view of the movable body viewed from the other side in the axial direction. Figure 10 is a cross-sectional view showing the second jig assembled to the holder. Figure 11 is a cross-sectional view showing the lens frame and lens positioned in the XY direction via the second jig, and a partially enlarged cross-sectional view of the area where the first reference plane is provided. Figure 12 is a cross-sectional view showing the lens frame and lens positioned in the Z-axis direction via the first jig. Figure 13 is a partially enlarged cross-sectional view (a cross-sectional view cut at position A-A in Figure 12) of the area where the first reference plane is provided, cut in a direction perpendicular to Figure 11. Figure 14 is a plan view showing the tip of the first jig rotated to a position overlapping with the second reference plane.

[0009] An embodiment of a tilt device to which the present invention is applied will be described below with reference to the drawings.

[0010] Figure 1 is an external perspective view of the tilt device 1 that pivots the lens 2, and the first jig 10 and second jig 20 used for positioning the lens 2. Figure 2 is an exploded perspective view of the tilt device 1 viewed from one side L1 in the axial direction. Figure 3 is an exploded perspective view of the tilt device 1 viewed from the other side L2 in the axial direction. Figure 4 is a cross-sectional view of the tilt device 1 cut by a plane perpendicular to the axial direction. Figure 5 is a cross-sectional view of the tilt device 1 cut by a plane containing the first axis R1 and the central axis L. Figure 6 is a cross-sectional view of the tilt device 1 cut by a plane containing the second axis R2 and the central axis L. Figure 7 is an exploded perspective view of the gimbal frame 70, the first thrust bearing member 71, and the second thrust bearing member 72. Figure 8 is an exploded perspective view of the movable body 4 viewed from one side L1 in the axial direction. Figure 9 is an exploded perspective view of the movable body 4 viewed from the other side L2 in the axial direction.

[0011] The tilt device 1 performs a tilt operation to swing an object to be oscillated. The object to be oscillated is not particularly limited, but examples include optical elements such as lenses and prisms, reflective elements such as mirrors, antennas, light-emitting elements such as laser diodes, etc. The tilt device 1 performs a tilt operation to swing the object to be oscillated based on a control signal from a higher-level device, for example. Below, an embodiment of the tilt device 1 is described, assuming that the object to be oscillated is a lens 2 and that it is incorporated into an imaging device equipped with an imaging optical system including the lens 2.

[0012] (Overall Configuration) As shown in Figures 1 to 6, the tilt device 1 comprises a movable body 4 having a lens 2 held in a lens frame 3, a support body 6 having a case 5 surrounding the outer circumference of the movable body 4, a gimbal mechanism 7 connecting the movable body 4 and the support body 6, and a magnetic drive mechanism 8 for oscillation that generates a magnetic driving force to oscillate the movable body 4. Although the lens 2 shown in the drawings of this specification has a flat lens surface, which differs from the actual shape, the shape of the lens surface is not particularly limited. For example, the lens surface may be either a convex lens surface or a concave lens surface.

[0013] As shown in Figures 5 and 6, in this embodiment of the tilt device 1, the pivot center P of the movable body 4 is located outside the lens 2, which is the object to be pivoted, and the lens 2 is separated from the pivot center P. The central axis L connecting the center of the lens 2 and the pivot center P coincides with the optical axis of the lens 2. In the following description, the direction along the central axis L is referred to as the axial direction, with one side of the axial direction being L1 and the other side being L2.

[0014] In the following explanation, the three mutually orthogonal axes are referred to as the X-axis, Y-axis, and Z-axis. The Z-axis coincides with the central axis L when the lens 2, which is the object being oscillated, is located at the origin. In the following explanation, the direction along the X-axis is referred to as the X-axis direction, the direction along the Y-axis is referred to as the Y-axis direction, and the direction along the Z-axis is referred to as the Z-axis direction. One side of the X-axis direction is referred to as the X1 direction, the other side of the X-axis direction as the X2 direction, one side of the Y-axis direction as the Y1 direction, the other side of the Y-axis direction as the Y2 direction, one side of the Z-axis direction as the Z1 direction, and the other side of the Z-axis direction as the Z2 direction. The Z1 direction coincides with one side L1 of the axial direction, and the Z2 direction coincides with the other side L2 of the axial direction.

[0015] The gimbal mechanism 7 supports the movable body 4 so that it can pivot around the first axis R1, and also supports the movable body 4 so that it can pivot around the second axis R2. The first axis R1 and the second axis R2 intersect each other and intersect the central axis L at the pivot center P. The first axis R1 and the second axis R2 are tilted around the Z axis with respect to the X axis and the Y axis. In this embodiment, the first axis R1 and the second axis R2 are tilted 45° around the Z axis with respect to the X axis and the Y axis. In the following description, the direction along the first axis R1 is referred to as the first axis direction, and the direction along the second axis R2 is referred to as the second axis direction.

[0016] The tilt device 1 performs a combination of two actions: one that swings the movable body 4 around a first axis centered on the first axis R1, and another that swings the movable body 4 around a second axis centered on the second axis R2. This adjusts the angular position of the lens 2 positioned on the movable body 4 around the X axis and around the Y axis.

[0017] (Movable body) As shown in Figures 2, 3, 5, and 6, the movable body 4 includes a holder 9 to which the lens frame 3 is fixed. The holder 9 includes a cylindrical portion 91 extending in the axial direction and a magnet fixing portion 92 protruding outward from the cylindrical portion 91. The lens frame 3 is fixed to the tip of one side L1 in the axial direction of the cylindrical portion 91. The cylindrical portion 91 is circular when viewed from the axial direction. The magnet fixing portion 92 is rectangular when viewed from the axial direction. The diagonal directions of the magnet fixing portion 92 coincide with the first axial direction and the second axial direction. The magnet fixing portion 92 has cutouts at its four diagonal corners. As shown in Figures 5 and 6, the pivot center P is located inside the magnet fixing portion 92.

[0018] The movable body 4 further includes a weight member 40 fixed to the other end L2 in the axial direction of the holder 9. The weight member 40 is cylindrical and fixed to the other end L2 in the axial direction of the cylindrical portion 91. The weight member 40 is a member for bringing the center of gravity G of the movable body 4 closer to the pivot center P. As shown in Figures 5 and 6, in this embodiment, the center of gravity G of the movable body 4 and the pivot center P coincide.

[0019] (Case) Case 5 comprises a body portion 51 surrounding the outer circumference of the holder 9, an end plate portion 52 extending inward from one end L1 in the axial direction of the body portion 51, and a protruding portion 53 extending outward from the other end L2 in the axial direction of the body portion 51. The body portion 51 and the protruding portion 53 are rectangular when viewed from the axial direction, with the four diagonal corners cut out. As shown in Figures 1, 5, and 6, the cylindrical portion 91 of the holder 9 passes through a circular opening 54 provided in the center of the end plate portion 52 and extends to one side L1 in the axial direction of the end plate portion 52. On both sides of the opening 54 in the first axial direction, a pair of wall portions 55 are provided that protrude from the end plate portion 52 to one side L1 in the axial direction.

[0020] As shown in Figure 5, the tips of the pair of wall portions 55 extend beyond the lens frame 3, which is located at the end of one side L1 in the axial direction of the movable body 4, to the other side L1 in the axial direction. The lens frame 3A, shown by the dashed line in Figure 5, is fixed to the tips of the pair of wall portions 55. The lens 2A is held in the lens frame 3A. An image sensor (not shown) is located on the other side L1 in the axial direction relative to the lens 2A.

[0021] The tilt device 1 in this embodiment is used by being incorporated into an imaging device. Lens 2A, together with lens 2, constitutes the imaging optical system of the imaging device, but does not swing because it is fixed to the case 5 via the lens frame 3A. Therefore, lens 2A is a fixed lens, and lens frame 3A is a fixed lens frame. On the other hand, lens 2 is a movable lens, and lens frame 3 is a movable lens frame. The pair of wall portions 55 provided on the case 5 are lens frame fixing portions.

[0022] The imaging optical system includes a lens group containing lens 2 and lens 2A. The configuration of the lens group is not particularly limited, as long as it includes lens 2 and lens 2A. For example, lens 2 can be a concave lens and lens 2A can be a convex lens. The tilt device 1 causes lens 2, which is one of the lenses in the lens group, to oscillate relative to the other lenses in the lens group, for example, lens 2A. This corrects image blur and aberrations.

[0023] As shown in Figures 1, 2, and 6, the case 5 is provided with two jig insertion holes H on both sides of the opening 54 in the second axial direction, opening to one side L1 in the axial direction. The jig insertion holes H are holes for inserting the first jig 10 shown in Figure 1. The first jig 10 is used to position the lens 2 in the axial direction, i.e., in the optical axis direction. Details of the method for positioning the lens 2 using the first jig 10 will be described later.

[0024] (Magnetic drive mechanism for oscillation) As shown in Figures 2, 3, and 4, the magnetic drive mechanism 8 for oscillation comprises a first magnet 81X and a second magnet 81Y fixed to a holder 9, and a first coil 82X and a second coil 82Y fixed to a case 5. Alternatively, the first coil 82X and the second coil 82Y may be placed in the holder 9, and the first magnet 81X and the second magnet 81Y may be placed in the case 5.

[0025] First magnets 81X are fixed to both sides of the magnet fixing portion 92 of the holder 9 in the Y-axis direction. Second magnets 81Y are fixed to both sides of the magnet fixing portion 92 in the X-axis direction. The first magnets 81X and the second magnets 81Y are arranged in recesses provided on the sides of the magnet fixing portion 92. In addition, yoke members may be attached to the back side of the first magnet 81X and the back side of the second magnet 81Y in the magnet fixing portion 92.

[0026] The body portion 51 of case 5 is provided with a pair of first coil placement holes 57X located on both sides in the Y-axis direction of the movable body 4, and a pair of second coil placement holes 57Y located on both sides in the X-axis direction of the movable body 4. As shown in Figure 4, the first coil 82X of the oscillating magnetic drive mechanism 8 is placed in the first coil placement hole 57X. The second coil 82Y of the oscillating magnetic drive mechanism 8 is placed in the second coil placement hole 57Y.

[0027] As shown in Figure 4, the rocking magnetic drive mechanism 8 includes two sets of first magnets 81X and first coils 82X facing each other in the Y-axis direction, and two sets of second magnets 81Y and second coils 82Y facing each other in the X-axis direction. The sets of first magnets 81X and first coils 82X generate a magnetic driving force that rocks the movable body 4 around the X-axis. The sets of second magnets 81Y and second coils 82Y generate a magnetic driving force that rocks the movable body 4 around the Y-axis.

[0028] As shown in Figures 2 and 3, the first coil 82X and the second coil 82Y are electrically connected to the flexible printed circuit board 83 and power is supplied via the flexible printed circuit board 83. The flexible printed circuit board 83 is fitted into a recess provided on the outer circumferential surface of the body portion 51 of the case 5.

[0029] As shown in Figure 4, a magnetic sensor 84 is connected to the flexible printed circuit board 83, which is positioned inside the first coil 82X and the second coil 82Y. In addition, a magnetic member 85 for returning to the origin is fixed to the back side of the first coil 82X and the second coil 82Y on the outer surface of the flexible printed circuit board 83. The oscillating magnetic drive mechanism 8 detects the angular position of the lens 2 based on the output of the magnetic sensor 84. When power supply to the first coil 82X and the second coil 82Y is stopped, the lens 2 returns to the origin position due to the magnetic attractive force of the first magnet 81X and the second magnet 81Y attracting the magnetic member 85.

[0030] (Gimbal Mechanism) As shown in Figures 2, 3, and 7, the gimbal mechanism 7 includes a gimbal frame 70, a pair of first thrust bearing members 71 that make point contact with the gimbal frame 70 on the first axis R1, and a pair of second thrust bearing members 72 that make point contact with the gimbal frame 70 on the second axis R2. As shown in Figure 7, the gimbal frame 70 includes an annular frame body 700 when viewed from the axial direction, a pair of first extensions 701 extending from the inner peripheral edges of both ends of the frame body 700 in the direction of the first axis R1 to one side L1 in the axial direction, and a pair of second extensions 702 extending from the outer peripheral edges of both ends of the frame body 700 in the direction of the second axis R2 to one side L1 in the axial direction. The tip of each first extension 701 and the tip of each second extension 702 are provided with a concave curved surface 703 that is recessed toward the side of the pivot center P.

[0031] Each of the pair of first thrust bearing members 71 and the pair of second thrust bearing members 72 comprises a first plate portion 73 extending in the axial direction and a second plate portion 74 bent at approximately a right angle from one end L1 in the axial direction of the first plate portion 73. A convex curved surface 704 is provided in the center of the width direction of the first plate portion 73, projecting toward the pivot center P. The convex curved surface 704 is a contact point that makes point contact with the concave curved surface 703 of the gimbal frame 70. In addition, a pair of arm portions 75 are provided at both ends of the width direction of the first plate portion 73, bending toward the pivot center P.

[0032] A pair of first thrust bearing members 71 are arranged on the movable body 4. In this embodiment, a holder recess 94 for attaching the first thrust bearing members 71 is provided in the magnet fixing portion 92 of the holder 9. As shown in Figure 5, the holder recess 94 opens into the end face of the other side L2 in the axial direction of the magnet fixing portion 92 and recesses into the one side L1 in the axial direction. The holder recess 94 is provided at two locations on opposite sides in the first axial direction with respect to the pivot center P. The first thrust bearing members 71 are mounted in the holder recess 94 with their convex curved surface 704 facing inward.

[0033] A pair of second thrust bearing members 72 are arranged on the support 6. In this embodiment, a case recess 58 for attaching the second thrust bearing members 72 is provided in the body portion 51 of the case 5. As shown in Figure 6, the case recess 58 opens to the end face of the other side L2 in the axial direction of the body portion 51 and recesses into the one side L1 in the axial direction. The case recess 58 is provided at two locations on opposite sides in the second axial direction with respect to the pivot center P. The second thrust bearing members 72 are mounted in the case recess 58 with their convex curved surface 704 facing inward.

[0034] When assembling the gimbal mechanism 7, the pair of first extensions 701 extending from the frame body 700 of the gimbal frame 70 to one side L1 in the axial direction are bent inward before being inserted into the holder recess 94, so that the concave curved surface 703 of the first extensions 701 and the convex curved surface 704 of the first thrust receiving member 71 face each other in the first axial direction. After that, when the inward bending of the first extensions 701 is released, the two concave curved surfaces 703 are biased toward the outer circumference, so that the concave curved surfaces 703 maintain point contact with the convex curved surface 704 at two points on the first axis R1. As a result, the holder 9 is supported by the gimbal frame 70 so that it can swing around the first axis R1.

[0035] Similarly, a pair of second extensions 702 extending from the frame body 700 of the gimbal frame 70 toward one side L1 in the axial direction are bent toward the inner circumference and then inserted into the case recess 58, so that the concave curved surface 703 of the second extension 702 and the convex curved surface 704 of the second thrust receiving member 72 face each other in the second axial direction. After that, when the inward bending of the second extension 702 is released, the two concave curved surfaces 703 are biased toward the outer circumference, so that the concave curved surfaces 703 maintain point contact with the convex curved surface 704 at two points on the second axis R2. As a result, the gimbal frame 70 is supported by the case 5 so that it can swing around the second axis R2.

[0036] The gimbal mechanism 7 may differ from that of this embodiment. For example, the arrangement of the concave surface 703 and the convex surface 704 may be reversed. Alternatively, instead of forming the convex surface 704 by press working, a part made by welding a sphere may be used. Or, instead of generating a biasing force by bending the gimbal frame 70, a spring member that bends in the first axial direction may be used as the first thrust bearing member 71, and a spring member that bends in the second axial direction may be used as the second thrust bearing member 72, thereby biasing one of the convex surface 704 and the concave surface 703 relative to the other.

[0037] (Lens frame) As shown in Figures 8 and 9, the lens frame 3 comprises an annular frame portion 31 that holds the lens 2 and arm portions 32 that protrude outward from the frame portion 31. The arm portions 32 are provided at two locations on opposite sides in the radial direction. As shown in Figure 1, the lens frame 3 is fixed to the tip of a holder 9 that protrudes from the opening 54 of the case 5 to one side L1 in the axial direction. When the lens frame 3 is fixed to the tip of the holder 9, it is positioned so that the arm portions 32 protrude on both sides in the second axial direction. Therefore, the arm portions 32 are positioned at an angular position that does not interfere with the wall portion 55 of the case 5. The arm portions 32 extend to the outer circumference of the opening 54 of the case 5 and overlap with the end plate portion 52 from one side L1 in the axial direction.

[0038] As shown in Figures 8 and 9, each of the two arm portions 32 is provided with a first positioning hole H1 that penetrates in the axial direction. The inner periphery of the end plate portion 52 surrounding the opening 54 of the case 5 and the magnet fixing portion 92 of the holder 9 are positioned at a location that overlaps with the first positioning hole H1 when viewed from the axial direction. As shown in Figures 1, 2, and 6, the inner periphery of the end plate portion 52 surrounding the opening 54 is provided with a notch 56 cut out in the portion that overlaps with the first positioning hole H1 when viewed from the axial direction. The magnet fixing portion 92 of the holder 9 is provided with a second positioning hole H2 that opens on one side L1 in the axial direction, at a location that overlaps with the first positioning hole H1 and the notch 56 when viewed from the axial direction.

[0039] The first positioning hole H1 and the second positioning hole H2 are holes for inserting the second jig 20 shown in Figure 1. The second jig 20 is used to position the lens 2 in the XY direction. Details of the positioning method using the second jig 20 will be described later.

[0040] As shown in Figures 6 and 8, an annular rib 33 is provided on the end face of one side L1 in the axial direction of the frame portion 31, projecting toward the one side L1 in the axial direction. The tip surface of the annular rib 33 functions as a second reference surface S2 for contacting the first jig 10 when performing Z-axis positioning using the first jig 10 shown in Figure 1.

[0041] As shown in Figures 8 and 9, the outer surface of the frame portion 31 has one recess 34 on each side of the circumferential direction of each arm portion 32, which is recessed inward. As shown in Figures 1 and 2, the four recesses 34 function as adhesive reservoirs, and adhesive GL for fixing the lens frame 3 to the holder 9 is placed there. The adhesive GL injected into the recesses 34 spreads from the recesses 34 into the gap between the frame portion 31 and the cylindrical portion 91 and hardens.

[0042] As shown in FIG. 9, an arc-shaped rib 35 protruding toward the other side L2 in the axial direction is provided on the outer peripheral edge of the end face on the other side L2 in the axial direction of the frame portion 31. The arc-shaped ribs 35 are provided at two positions on the opposite sides in the radial direction. The two arc-shaped ribs 35 are provided at an angular position centered on the first axial direction, and are provided at an angular position shifted from the angular position where the arm portion 32 and the recess 34 are provided. As shown in FIG. 8, the holder 9 is provided with an arc-shaped recess 93 obtained by cutting out a part of the circumferential direction of the tip end face of the cylindrical portion 91. The arc-shaped recess 93 is provided at an angular position centered on the first axial direction. The holder 9 and the lens frame 3 are assembled in a state where the arc-shaped recess 93 and the arc-shaped rib 35 are fitted together.

[0043] (Lens positioning) When assembling the tilt device 1, with the lens frame 3 separated from the holder 9, the holder 9 and the case 5 are connected via the gimbal mechanism 7. Thereafter, the lens frame 3 is fixed to the holder 9 to complete the movable body 4. Note that the weight member 40 may be fixed to the holder 9 before connecting the gimbal mechanism 7 to the holder 9, or may be fixed to the holder 9 after connecting the gimbal mechanism 7 to the holder 9.

[0044] [[ID=⑥]]In this embodiment, while the holder 9 and the case 5 are connected via the gimbal mechanism 7, an operation of fixing the lens frame 3 to the holder 9 is performed. At this time, by using the second jig 20, positioning in the XY directions of the lens frame 3 and the lens 2 with respect to the swing center P, in other words, positioning in a plane orthogonal to the axial direction is performed. Further, by using the first jig 10, positioning in the Z-axis direction of the lens frame 3 and the lens 2 with respect to the swing center P, in other words, positioning in the axial direction is performed.

[0045] (Positioning in the XY direction) Figure 10 is a cross-sectional view showing the second jig 20 assembled to the holder 9. Figure 11 is a cross-sectional view showing the lens frame 3 and lens 2 positioned in the XY direction via the second jig 20, and a partially enlarged cross-sectional view of the area where the first reference plane S1 is provided. The positioning of the lens frame 3 and lens 2 in the XY direction and the Z-axis direction is performed without energizing the oscillating magnetic drive mechanism 8, with the holder 9 held at the origin position by the magnetic attractive force of the first magnet 81X and the second magnet 81Y attracting the magnetic member 85.

[0046] As shown in Figure 1, the second jig 20 is a rod-shaped member with a circular cross-section and extending in a straight line. As described above, the lens frame 3 has two first positioning holes H1 on the radially opposite side of the lens 2, and the holder 9 has two second positioning holes H2 on the radially opposite side of the cylindrical portion 91. Therefore, by inserting the two second jigs 20 into the first positioning holes H1 and the second positioning holes H2, respectively, the lens frame 3 can be positioned in the XY direction relative to the holder 9.

[0047] As shown in Figure 10, when the holder 9 is held at the origin position, the two second positioning holes H2 provided in the magnet fixing portion 92 of the holder 9 both face one side L1 in the axial direction. As described above, the end plate portion 52 of the case 5 has two notches 56 that overlap with the second positioning holes H2 when viewed from the axial direction. Therefore, as shown in Figure 10, when inserting the second jig 20 into the two second positioning holes H2 from one side L1 in the axial direction, the end plate portion 52 does not interfere with the second jig 20. Next, the two second jigs 20 are each passed through the first positioning hole H1 of the lens frame 3, and the lens frame 3 is slid along the second jig 20 to the other side L2 in the axial direction. Then, as shown in Figure 11, the lens frame 3 is placed on the tip surface of the cylindrical portion 91. At this time, since the lens frame 3 is positioned in the XY direction, the arc-shaped rib 35 of the lens frame 3 fits into the arc-shaped recess 93 of the cylindrical portion 91.

[0048] When the holder 9 and the case 5 are connected via the gimbal mechanism 7, the positional relationship in the XY direction of the swing center P with respect to each part of the holder 9 is determined. Therefore, by using the second jig 20 to position the lens frame 3 in the XY direction with respect to the holder 9, the lens frame 3 can be positioned in the XY direction with respect to the swing center P. And thereby, the XY-direction positioning between the center point P0 of the lens surface of the lens 2 held by the lens frame 3 and the swing center P can be performed. For example, the positions of the center point P0 of the lens surface and the swing center P in the XY direction can be made to coincide.

[0049] (Z-axis direction positioning) As shown in FIG. 1, the first jig 10 includes a rod-shaped shaft portion 11 having a circular cross-section and extending linearly, and an arm portion 12 fixed or integrally formed on the shaft portion 11. The arm portion 12 includes a tip portion 13 extending in a direction orthogonal to the shaft portion 11. The first jig 10 is manufactured such that the distance from the bottom surface of the shaft portion 11 to the tip portion 13 is a preset dimension.

[0050] FIG. 12 is a cross-sectional view showing a state where the lens frame 3 and the lens 2 are positioned in the Z-axis direction via the first jig 10. When performing the Z-axis direction positioning, as shown in FIG. 12, the shaft portion 11 of the first jig 10 is inserted into the jig insertion hole H of the case 5, and the bottom surface of the shaft portion 11 is abutted against the first reference surface S1 disposed at the bottom of the jig insertion hole H. As shown in FIGS. 11 and 12, the first reference surface S1 is provided on the second thrust receiving member 72 held by the case 5. In this embodiment, the second plate portion 74 of the second thrust receiving member 72 constitutes the first reference surface S1.

[0051] The second thrust receiving member 72 is held by the case 5 with the first reference surface S1 exposed on one side L1 in the axial direction. As shown in the partially enlarged view of FIG. 11, the case recess 58 for attaching the second thrust receiving member 72 is provided at a position overlapping the jig insertion hole H for inserting the first jig 10 in the axial direction, and the case recess 58 opens at the bottom surface of the jig insertion hole H.

[0052] Figure 13 is a partially enlarged cross-sectional view obtained by cutting the area where the first reference surface S1 is provided in a direction perpendicular to Figure 11, and is a cross-sectional view taken at position A-A in Figure 12. As can be seen from Figure 1, the jig insertion hole H is a circular hole when viewed from the axial direction. On the other hand, as shown in Figure 4, the case recess 58 is a recess with a rectangular cross-section. As shown in Figure 13, the opening width of the case recess 58 in the direction perpendicular to the second axial direction is larger than the inner diameter of the jig insertion hole H. Also, the width of the second thrust bearing member 72 is larger than the inner diameter of the jig insertion hole H. Therefore, the second thrust bearing member 72 is attached so that both ends of the second plate portion 74 in the width direction are in contact with the bottom surface 59 of the case recess 58 from the other side L2 in the axial direction. The central portion of the second plate portion 74 in the width direction is exposed at the bottom of the jig insertion hole H facing one side L1 in the axial direction, and functions as the first reference surface S1.

[0053] Figure 14 is a plan view showing the state in which the tip portion 13 of the first jig 10 has been rotated to a position that coincides with the second reference plane S2. As shown in Figures 8, 11, and 12, the lens frame 3 is provided with a second reference plane S2 facing one side L1 in the axial direction at the tip of the annular rib 33 that protrudes from the front surface of the frame portion 31. After inserting the first jig 10 into the two jig insertion holes H, the two first jigs 10 are rotated around the shaft portion 11, as shown in Figure 14, so that the tip portions 13 of the arm portions 12 face the center of the lens frame 3. As a result, the tip portions 13 of the arm portions 12 coincide with the second reference plane S2 from one side L1 in the axial direction. In this state, the lens frame 3 is positioned so that it contacts each tip portion 13 from the other side L2 in the axial direction. The lens frame 3 is fixed, for example, by injecting adhesive GL into the recess 34 of the lens frame 3, as described above, and allowing the adhesive GL that has spread into the gap between the cylindrical portion 91 and the frame portion 31 to harden.

[0054] By this method, as shown in Figure 12, the distance D1 between the first reference plane S1 and the second reference plane S2 becomes a dimension that matches the distance between the bottom surface and the tip portion 13 of the shaft portion 11 of the first jig 10, and the lens frame 3 and lens 2 are positioned in the axial direction. The lens 2 is fixed to the lens frame 3, for example, so that the axial distance between the center point P0 of the lens surface and the second reference plane S2 is a predetermined dimension. As a result, for example, when the lens frame 3 is positioned so that the distance between the first reference plane S1 and the second reference plane S2 is D1, the positioning can be performed so that the axial distance between the center point P0 of the lens surface and the pivot center P is D.

[0055] In this method, the jig interposed between the first reference surface S1 provided on the gimbal mechanism 7 and the second reference surface S2 provided on the lens frame 3 is only one component of the first jig 10. Therefore, since there are fewer components interposed between the pivot center P and the lens 2 which is the object to be pivoted, the lens 2 can be positioned with high precision relative to the pivot center P.

[0056] (Effects) As described above, the tilt device 1 of this embodiment includes a movable body 4 which is a lens 2 which is the object to be swung and a lens frame 3 which is a holding member that holds the object to be swung, a support body 6 which is a case 5 that surrounds the movable body 4, and a gimbal mechanism 7 that connects the support body 6 and the movable body 4. When the central axis L is defined as the straight line connecting the pivot center P, which is far from the object to be pivoted, and the object to be pivoted, the axis intersecting the central axis L at the pivot center P is defined as the first axis R1, the axis intersecting the central axis L and the first axis R1 at the pivot center P is defined as the second axis R2, the direction along the central axis L is defined as the axial direction, and the side on which the object to be pivoted is located relative to the pivot center P is defined as one side L1 of the axial direction, the gimbal mechanism 7 comprises a gimbal frame 70, a pair of first thrust bearing members 71 that make point contact with the gimbal frame 70 on the first axis R1, and a pair of second thrust bearing members 72 that make point contact with the gimbal frame 70 on the second axis R2. The pair of first thrust bearing members 71 are arranged on the movable body 4, and the pair of second thrust bearing members 72 are arranged on the case 5. Each of the pair of second thrust bearing members 72 is provided with a first reference surface S1 for positioning the lens frame 3, which is a holding member, in the axial direction, and is held in the case 5 with the first reference surface S1 exposed toward one side L1 in the axial direction.

[0057] In this embodiment, the second thrust bearing member 72 is held in the case 5 with the first reference surface S1 provided on the second thrust bearing member 72 exposed to one side in the axial direction. Therefore, the axial positioning of the lens 2, which is the object to be oscillated, and the lens frame 3, which is the holding member that holds the object to be oscillated, can be performed by directly contacting the positioning jig with respect to the first reference surface S1. The second thrust bearing member 72 is a component that defines the second axis R2 passing through the pivot center P. Therefore, this method reduces the number of components interposed between the pivot center P and the object to be oscillated when positioning the object to be oscillated. Thus, even when the object to be oscillated is far from the pivot center P, the positional accuracy of the object to be oscillated with respect to the pivot center P can be improved.

[0058] In this embodiment, both of the pair of second thrust bearing members 72 are provided with a first reference surface S1, and there are two locations where the first reference surface S1 is exposed. However, the number of locations where the first reference surface S1 is exposed is not limited to two. That is, it is sufficient that at least one of the pair of second thrust bearing members 72 is provided with a first reference surface S1 for positioning the lens frame 3, which is a holding member, in the axial direction.

[0059] In this embodiment, case 5 is provided with a jig insertion hole H that opens on one side L1 in the axial direction, and a first reference surface S1 is positioned at the bottom of the jig insertion hole H. This allows the first reference surface S1, which is positioned at a distance from the object to be oscillated on the other side L2 in the axial direction, to be exposed. Furthermore, the jig insertion hole H can be used as a holding part for holding a positioning jig. Note that the structure in which the first reference surface S1 is exposed toward one side L1 in the axial direction is not limited to the structure in which it is positioned at the bottom of the jig insertion hole H.

[0060] In this embodiment, when the direction along the second axis R2 is defined as the second axis R2 direction, each of the pair of second thrust bearing members 72 is provided with a first reference surface S1, and the jig insertion hole H and the first reference surface S1 are positioned at two locations on one side and the other side in the second axis R2 direction relative to the movable body 4. This allows axial positioning to be performed at two locations on the radially opposite sides of the movable body 4. Therefore, it is possible to avoid the object being oscillated being positioned at an angle.

[0061] The second thrust bearing member 72 in this embodiment comprises a first plate portion 73 extending in the axial direction and a second plate portion 74 bent from the axial end of the first plate portion 73. The first plate portion 73 is provided with a convex curved surface 704, which is a contact point that makes point contact with the gimbal frame 70 on the second axis R2, and the second plate portion 74 is provided with a first reference surface S1. With such a part shape, the first reference surface S1 can be provided perpendicular to the axial direction. If the second plate portion 74 is provided at one end L1 in the axial direction of the second thrust bearing member 72, the first reference surface S1 can be easily exposed. Furthermore, since the part equipped with the first reference surface S1 and the convex curved surface 704 can be manufactured by press working, the part cost can be reduced.

[0062] In this embodiment, the lens frame 3, which is a holding member for holding the object to be oscillated, has a second reference surface S2 facing one side L1 in the axial direction. When viewed from the axial direction, at least a portion of the second reference surface S2 is positioned at the same angular position as the first reference surface S1 with respect to the object to be oscillated. As shown in Figure 14, in this embodiment, when viewed from the axial direction, the first jig 10 is positioned on both sides in the second axial direction with respect to the lens 2, which is the object to be oscillated. That is, the first reference surface S1 is positioned at angular positions on both sides in the second axial direction with respect to the lens 2, which is the object to be oscillated. And since the second reference surface S2 is an annular surface that surrounds the entire circumference of the lens 2, at least a portion of the second reference surface S2 is positioned at the same angular position as the first reference surface S1 with respect to the lens 2. With this arrangement, even if the length of the arm portion 12 of the first jig 10 is shortened, the tip portion 13 can be brought into contact with the second reference surface S2. If the length of the arm portion 12 is short, the decrease in positioning accuracy caused by the tilt of the first jig 10 can be reduced.

[0063] The second reference plane S2 may also be provided in a different location on the lens frame 3 than in this embodiment. For example, the annular rib 33 may not be provided on the frame portion 31, and the end face of one side L1 in the axial direction of the frame portion 31 may be used as the second reference plane S2. Alternatively, the second reference plane S2 may be provided at the tip of the arm portion 32.

[0064] In this embodiment, the movable body 4 includes a holder 9 to which the lens frame 3 is fixed at one end L1 in the axial direction. A pair of first thrust bearing members 71 are arranged on the holder 9. By making the parts for attaching the first thrust bearing members 71 separate from the lens frame 3 in this way, the lens 2 can be swung around a pivot center P that is far from the lens 2.

[0065] In this embodiment, the lens frame 3 is provided with a first positioning hole H1 that penetrates in the axial direction, and the holder 9 is provided with a second positioning hole H2 that opens on the side of the first positioning hole H1, at a position that overlaps with the first positioning hole H1 when viewed from the axial direction. Therefore, by inserting the second jig 20 into the first positioning hole H1 and the second positioning hole H2, the lens frame 3 and the lens 2 can be positioned in a direction perpendicular to the axial direction.

[0066] In this embodiment, the first positioning hole H1 and the second positioning hole H2 are provided at multiple positions separated in the circumferential direction around the central axis L. As shown in Figure 14, in this embodiment, the first positioning hole H1 and the second positioning hole H2 are provided at two locations on opposite sides in the second axial direction. Therefore, the lens frame 3 and the lens 2 can be positioned in a plane perpendicular to the axial direction. As can be seen from Figure 14, one of the two first positioning holes H1 and the second positioning hole H2 is circular, and the other is an elongated hole in the second axial direction. Therefore, it is possible to avoid the situation where one of the two second jigs 20 cannot be inserted into the first positioning hole H1 and the second positioning hole H2 due to variations in the dimensional accuracy of each part.

[0067] The movable body 4 in this embodiment includes a weight member 40 fixed to the other end L2 in the axial direction of the holder 9. This allows the center of gravity G of the movable body 4 to be shifted to the other L2 in the axial direction, bringing it closer to the pivot center P. Bringing the center of gravity G closer to the pivot center P reduces the oscillation load. Consequently, the magnets and coils of the magnetic drive mechanism 8 for oscillation can be miniaturized, and the power consumption when oscillating the lens can be reduced.

[0068] In this embodiment, a recess 34 is provided in the lens frame 3, and the lens frame 3 is fixed to the holder 9 via an adhesive placed in the recess 34. When the adhesive GL is injected into the recess 34, the adhesive GL spreads into the gap between the lens frame 3 and the holder 9. Therefore, by hardening the adhesive GL while the lens frame 3 is precisely positioned in the axial direction, the axial positional accuracy of the lens frame 3 can be improved.

[0069] In this embodiment, the object to be oscillated is the lens 2 (movable lens). The holding member is the lens frame 3 (movable lens frame) that holds the movable lens. The central axis L coincides with the optical axis of the lens 2 (movable lens). As a result, the lens 2 can be oscillated around the oscillation center P on the optical axis of the lens 2, thereby enabling image blur correction and aberration correction.

[0070] In this embodiment, when a lens 2A (fixed lens) held by a lens frame 3A (fixed lens frame) is positioned on one side L1 in the axial direction relative to lens 2 (movable lens), the case 5 can be configured such that the outer circumference of the lens frame 3 (movable lens frame) is provided with a wall portion 55 extending to one side L1 in the axial direction, and the lens 2A (fixed lens) is fixed to the wall portion 55 (lens frame fixing portion) via the lens frame 3A (fixed lens frame). Therefore, the tilt device 1 can be incorporated into an imaging device that oscillates some of the lenses 2 of the imaging optical system relative to other lenses 2A. Thus, an imaging device capable of image blur correction and aberration correction can be provided.

[0071] (Summary) The present invention can take the following forms. (1) A movable body comprising an object to be oscillated and a holding member for holding the object to be oscillated; a support body comprising a case surrounding the movable body; and a gimbal mechanism connecting the support body and the movable body, wherein the central axis is defined as a straight line connecting the pivot center, which is far from the object to be oscillated, and the object to be oscillated, the axis intersecting the central axis at the pivot center is defined as the first axis, the axis intersecting the central axis and the first axis at the pivot center is defined as the second axis, the direction along the central axis is defined as the axial direction, and the side on which the object to be oscillated is located relative to the pivot center is defined as one side of the axial direction, the gimbal mechanism comprising a gimbal frame, a pair of first thrust bearing members that make point contact with the gimbal frame on the first axis, and a pair of second thrust bearing members that make point contact with the gimbal frame on the second axis, the pair of first thrust bearing members arranged on the movable body, and the pair of second thrust bearing members arranged on the case. A tilt device characterized in that at least one of the pair of second thrust bearing members is provided with a first reference surface for positioning the holding member in the axial direction, and the first reference surface is exposed to one side in the axial direction and held in the case.

[0072] (2) The tilt device according to (1) above, characterized in that the case is provided with a jig insertion hole opening on one side in the axial direction, and the first reference surface is positioned at the bottom of the jig insertion hole.

[0073] (3) The tilt device according to (1) or (2) above, characterized in that, when the direction along the second axis is defined as the second axis direction, each of the pair of second thrust bearing members is provided with the first reference surface, and the jig insertion hole and the first reference surface are arranged at two locations on one side and the other side in the second axis direction with respect to the movable body.

[0074] (4) The tilt device according to any one of (1) to (3) above, wherein the second thrust bearing member comprises a first plate portion extending in the axial direction and a second plate portion bent from the axial end of the first plate portion, the first plate portion is provided with a contact portion that makes point contact with the gimbal frame on the second axis, and the second plate portion is provided with the first reference surface.

[0075] (5) The tilt device according to any one of (1) to (4) above, wherein the holding member has a second reference surface facing one side in the axial direction, and when viewed from the axial direction, at least a part of the second reference surface is positioned at the same angular position as the first reference surface with respect to the object to be oscillated.

[0076] (6) The tilt device according to any one of (1) to (5) above, wherein the movable body comprises a holder to which the holding member is fixed at one end in the axial direction, and the pair of first thrust bearing members are arranged in the holder.

[0077] (7) The tilt device according to (6) above, characterized in that the holding member is provided with a first positioning hole that penetrates in the axial direction, and the holder is provided with a second positioning hole that opens on the side of the first positioning hole at a position that overlaps with the first positioning hole when viewed from the axial direction.

[0078] (8) The tilt device according to (7) above, characterized in that the first positioning hole and the second positioning hole are provided at multiple positions separated in the circumferential direction with respect to the central axis.

[0079] (9) The tilt device according to (7) or (8) above, characterized in that the movable body comprises a weight member fixed to the other end of the holder in the axial direction.

[0080] (10) The tilt device according to any one of (7) to (9) above, characterized in that a recess is provided in the retaining member and the retaining member is fixed to the holder via an adhesive placed in the recess.

[0081] (11) The tilt device according to any one of (1) to (10) above, characterized in that the object to be oscillated is a movable lens, the holding member is a movable lens frame for holding the movable lens, and the central axis coincides with the optical axis of the movable lens.

[0082] (12) The tilt device according to any one of (1) to (11) above, wherein a fixed lens held in a fixed lens frame is arranged on one side in the axial direction relative to the movable lens, the case has a wall portion extending outward from the outer circumference of the movable lens frame to one side in the axial direction, and the fixed lens is fixed to the wall portion via the fixed lens frame.

Claims

1. A movable body comprising an object to be oscillated and a holding member for holding the object to be oscillated; a support body comprising a case surrounding the movable body; and a gimbal mechanism connecting the support body and the movable body, wherein the central axis is defined as a straight line connecting the pivot center, which is far from the object to be oscillated, and the object to be oscillated, the axis intersecting the central axis at the pivot center is defined as the first axis, the axis intersecting the central axis and the first axis at the pivot center is defined as the second axis, the direction along the central axis is defined as the axial direction, and the side on which the object to be oscillated is located relative to the pivot center is defined as one side of the axial direction, the gimbal mechanism comprising a gimbal frame, a pair of first thrust bearing members that make point contact with the gimbal frame on the first axis, and a pair of second thrust bearing members that make point contact with the gimbal frame on the second axis, the pair of first thrust bearing members arranged on the movable body, and the pair of second thrust bearing members arranged on the case. A tilt device characterized in that at least one of the pair of second thrust bearing members is provided with a first reference surface for positioning the holding member in the axial direction, and the first reference surface is exposed to one side in the axial direction and held in the case.

2. The tilt device according to claim 1, characterized in that the case is provided with a jig insertion hole opening on one side in the axial direction, and the first reference surface is positioned at the bottom of the jig insertion hole.

3. The tilt device according to claim 2, characterized in that, when the direction along the second axis is defined as the second axial direction, each of the pair of second thrust bearing members is provided with the first reference surface, and the jig insertion hole and the first reference surface are arranged at two locations on one side and the other side in the second axial direction with respect to the movable body.

4. The tilt device according to claim 3, wherein the second thrust bearing member comprises a first plate portion extending in the axial direction and a second plate portion bent from the axial end of the first plate portion, the first plate portion is provided with a contact portion that makes point contact with the gimbal frame on the second axis, and the second plate portion is provided with the first reference surface.

5. The tilt device according to claim 1, wherein the holding member has a second reference surface facing one side in the axial direction, and when viewed from the axial direction, at least a portion of the second reference surface is positioned at the same angular position as the first reference surface with respect to the object to be oscillated.

6. The tilt device according to claim 1, wherein the movable body comprises a holder to which the retaining member is fixed at one end in the axial direction, and the pair of first thrust bearing members are arranged in the holder.

7. The tilt device according to claim 6, characterized in that the holding member is provided with a first positioning hole that penetrates in the axial direction, and the holder is provided with a second positioning hole that opens on the side of the first positioning hole at a position that overlaps with the first positioning hole when viewed from the axial direction.

8. The tilt device according to claim 7, characterized in that the first positioning hole and the second positioning hole are provided at multiple positions separated in the circumferential direction with respect to the central axis.

9. The tilt device according to claim 6, characterized in that the movable body comprises a weight member fixed to the other end of the holder in the axial direction.

10. The tilt device according to claim 6, characterized in that a recess is provided in the retaining member, and the retaining member is fixed to the holder via an adhesive placed in the recess.

11. The tilt device according to claim 1, characterized in that the object to be oscillated is a movable lens, the holding member is a movable lens frame for holding the movable lens, and the central axis coincides with the optical axis of the movable lens.

12. The tilt device according to claim 11, wherein a fixed lens held in a fixed lens frame is arranged on one side in the axial direction relative to the movable lens, the case has a wall portion extending outward from the outer circumference of the movable lens frame to one side in the axial direction, and the fixed lens is fixed to the wall portion via the fixed lens frame.

Images