Drive mechanism, lens barrel, and imaging device

Abstract

The drive mechanism includes: a first member fixed to an output shaft of the motor; a rotating shaft having a threaded groove and having a central axis disposed substantially parallel to the output shaft; and a second member, one end side of which is engaged with the first member and the other end side of which is engaged with one end of the rotating shaft, the second member being allowed to move with respect to the first member in a first direction orthogonal to the output shaft. And a second member that is allowed to move in the second direction with respect to the rotating shaft and is restricted to move in the first direction with respect to the first member, and that is allowed to move in the second direction with respect to the rotating shaft and is restricted to move in the first direction with respect to the rotating shaft.

Description

Technical Field

[0001] This invention relates to a drive mechanism, a lens barrel, and an imaging device. Background Technology

[0002] A drive mechanism for driving a lens retaining frame using a lead screw and a engaging member (nut or rack, etc.) that engages with the lead screw has been proposed. In such a drive mechanism, if the output shaft of the motor that rotates the lead screw is offset from the axis of the lead screw, the load applied to the motor will increase. Therefore, a cross-slider coupling with an eccentric absorbing shaft has been proposed (for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2010-133476 Summary of the Invention

[0006] According to a first embodiment, the drive mechanism comprises: a first member fixed to the output shaft of a motor; a rotating shaft having a threaded groove and a central axis disposed substantially parallel to the output shaft; and a second member engaging with the first member at one end and engaging with one end of the rotating shaft at the other end, the second member being permitted to move relative to the first member in a first direction orthogonal to the output shaft and being restricted to move relative to the first member in a second direction substantially orthogonal to the first direction, the second member being permitted to move relative to the rotating shaft in the second direction and being restricted to move relative to the rotating shaft in the first direction.

[0007] According to the second method, the lens barrel includes: the aforementioned drive mechanism; and a lens retaining frame that engages with the threaded groove of the rotating shaft and is driven in the direction extending along the rotating shaft as the rotating shaft rotates.

[0008] According to the third method, the lens barrel includes: a motor having an output shaft for moving a lens retainer frame in the optical axis direction; a rotation shaft having a threaded groove and disposed substantially parallel to the output shaft; and an adjustment member disposed between the motor and the rotation shaft for adjusting the relative position of the central axis of the output shaft and the central axis of the rotation shaft, the adjustment member having multiple components.

[0009] According to the fourth method, the shooting device is equipped with the aforementioned lens barrel.

[0010] It should be noted that the configuration of the embodiments described below can be appropriately modified, and at least some of them can be replaced with other structures. Furthermore, the structural elements whose configuration is not particularly limited are not limited to the configuration disclosed in the embodiments, and can be configured in a position that can realize their function. Attached Figure Description

[0011] Figure 1 This is a diagram showing a camera having a lens barrel and a camera body according to the first embodiment.

[0012] Figure 2 This is a perspective view showing the relationship between the second fixed cylinder, the lens holding frame, and the drive source unit.

[0013] Figure 3 This is a three-dimensional diagram used to illustrate the structure of the lens holding frame and the drive source unit.

[0014] Figure 4 (A) is a cross-sectional view of the driving source unit. Figure 4 (B) is an enlarged view of the area near the first end of the lead screw.

[0015] Figure 5 (A) is the front view of the moving part. Figure 5 (B) is a three-dimensional view of the moving part. Figure 5 (C) and Figure 5 (D) is an exploded perspective view of the moving part.

[0016] Figure 6 This is a sectional view of the moving part.

[0017] Figure 7 (A) is a cross-sectional view showing the case where the cover is not fixed to the retaining part. Figure 7 (B) is a cross-sectional view showing the case where the annular member does not have a protrusion.

[0018] Figure 8 Figure (A) shows the state before the connecting part of the main body is housed in the receiving part of the lens retaining frame. Figure 8 (B) is a diagram showing the state in which the connecting part of the main body is housed in the receiving part of the lens holding frame.

[0019] Figure 9 yes Figure 8 (B) AA line section view.

[0020] Figure 10 (A) is a three-dimensional diagram showing the connection between the lead screw and the output shaft of the stepper motor via a joint mechanism. Figure 10 (B) and Figure 10 (C) is a three-dimensional view of the joint mechanism.

[0021] Figure 11 (A) and Figure 11 (B) is a perspective view showing the connector mechanism and the stepper motor.

[0022] Figure 12 (A) and Figure 12 (C) is a diagram showing the lead screw and the output shaft of the stepper motor not connected by a joint mechanism. Figure 12 (B) and Figure 12 (D) is a diagram showing the state in which the lead screw and the output shaft of the stepper motor are connected by a joint mechanism.

[0023] Figure 13 (A) is a perspective view showing the state in which the lead screw and the output shaft of the stepper motor are connected by the joint mechanism of modified Example 1. Figure 13 (B) is a perspective view illustrating the structure of the joint mechanism. Figure 13 (C) and Figure 13 (D) is a diagram showing the state in which the lead screw and the output shaft of the stepper motor are connected by a connector mechanism.

[0024] Figure 14 (A) is a perspective view showing the state in which the lead screw and the output shaft of the stepper motor are connected by the joint mechanism of modified Example 2. Figure 14 (B) is a perspective view illustrating the structure of the joint mechanism. Figure 14 (C) and Figure 14 (D) is a diagram showing the second component.

[0025] Figure 15 (A) and Figure 15 (B) is a sectional view used to illustrate the connection relationship between the lead screw, the joint mechanism, and the output shaft in modified example 2. Figure 15 (C) is an enlarged view of the first end of the lead screw in modified example 2.

[0026] Figure 16 This is a perspective view showing the relationship between the drive source unit, the lens holding frame, and the second fixing cylinder in the second embodiment.

[0027] Figure 17 This is a three-dimensional diagram used to illustrate the structure of the lens holding frame and the drive source unit.

[0028] Figure 18 (A) is a perspective view of the movable part according to the second embodiment. Figure 18 (B) is an exploded perspective view of the moving part.

[0029] Figure 19 This is a cross-sectional view used to illustrate the connection between the lens holding frame and the moving part. Detailed Implementation

[0030] First Implementation Method

[0031] Hereinafter, the lens barrel 100 of the first embodiment will be described in detail with reference to the accompanying drawings. Furthermore, the shapes, lengths, thicknesses, and other scales of the parts shown in the embodiment may not be identical to the actual object. Also, for ease of understanding, some elements are sometimes omitted from the illustrations in the figures. Additionally, in the sectional views, the shaded lines of some elements are omitted.

[0032] Figure 1 This is a diagram showing a camera 1 equipped with a lens barrel 100 and a camera body 200 according to the first embodiment. Additionally, in Figure 1 In the center line, the area above the center line indicates the Wide (wide-angle) mode, and the area below the center line indicates the Tele (telephoto) mode.

[0033] The camera body 200 internally includes an imaging element 201 and a control unit (not shown). The imaging element 201 is composed of photoelectric conversion elements such as CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor), which converts the image of the subject imaged by the imaging optical system (lens barrel 100 mounted on the camera body 200) into an electrical signal.

[0034] The control unit includes a CPU (Central Processing Unit) and performs unified control over the overall operation of the camera 1 involved in photography, including zoom drive and focus drive, in the imaging element 201 and the mounted lens barrel 100.

[0035] like Figure 1 As shown, the lens barrel 100 of this embodiment includes a first fixing barrel 10, a second fixing barrel 11, and a third fixing barrel 12, with the second fixing barrel 11 and the third fixing barrel 12 positioned closer to the inner diameter side than the first fixing barrel 10. A lens mounting member LM is mounted on the first fixing barrel 10. The lens mounting member LM engages with the body mounting member (not shown) of the camera body 200, thereby allowing the lens barrel 100 to be detachably mounted to the camera body 200. Furthermore, in this embodiment, the lens barrel 100 can be detached from the camera body 200, but this is not a limitation; the lens barrel 100 and the camera body 200 can also be integrated. Moreover, the camera body 200 can be used not only for still image photography but also for animation photography.

[0036] like Figure 1As shown, the lens barrel 100 of this embodiment has lens groups L1 to L6 arranged sequentially along a common optical axis OA. Lens groups L1 to L6 are respectively held in lens holding frames F1 to F6. In this embodiment, lens groups L2 and L4 are zoom lens groups that move in the direction of the optical axis OA during zooming. Lens group L5 is a focusing and zoom lens group. Lens groups L1 to L6 can each be composed of a single lens or multiple lenses. The positions of lens groups L1, L3, and L6 in the direction of the optical axis OA are fixed during zooming. By fixing the lens group L1 closest to the subject, the overall length of the lens barrel 100 can be fixed during zooming, and the change in the center of gravity position during use is small, which is therefore preferred. In addition, lens groups L4 and L5 are driven by a drive source (e.g., a stepper motor or VCM motor) provided in the third fixing barrel 12, which moves their positions in the direction of the optical axis OA. Therefore, the lens barrel 100 does not have a lens group that is mechanically linked to the zoom operation ring 13. The lens barrel 100 is equipped with a motor for moving the position of the lens group during zooming and a motor for changing the opening diameter of the aperture member S as drive sources.

[0037] The lens holding frame F2 is driven by the drive source unit 300. More specifically, when the zoom operation ring 13 is operated (rotated), a control unit (not shown) outputs a drive signal corresponding to its operation amount (rotation amount) to the drive source unit 300, and the drive source unit 300 drives the lens holding frame F2 based on the drive signal, thereby moving the lens holding frame F2 in the optical axis OA direction. The lens holding frame F2 and the drive source unit 300 will be described in detail below.

[0038] Figure 2 This is a perspective view showing the relationship between the second fixed cylinder 11, the lens holding frame F2, and the drive source unit 300. Figure 3 This is a perspective view illustrating the structure of the lens holding frame F2 and the drive source unit 300. Figure 4 (A) is a cross-sectional view of the drive source unit 300.

[0039] like Figure 2 As shown, the second fixing cylinder 11 has a generally cylindrical shape, and the lens holding frame F2 is disposed on the inner diameter side of the second fixing cylinder 11. Figure 3 As shown, three guide portions 500 are provided circumferentially on the outer periphery of the lens holding frame F2. Each guide portion 500 has a bearing 500a.

[0040] A guide portion 500 is formed on the inner circumference of the second fixed cylinder 11 and engages with a straight groove 111 extending in a direction parallel to the optical axis OA. Thus, the lens holding frame F2, driven by the drive source unit 300, is guided in a direction parallel to the optical axis OA. Alternatively, a guide rod extending in a direction parallel to the optical axis OA can be fixed to the second fixed cylinder 11, and the lens holding frame F2 can be guided by the guide rod.

[0041] like Figure 2 As shown, the drive source unit 300 includes a stepper motor 301, a lead screw 302 (rotation axis), and a linear guide member 303 that moves along the axis of the lead screw 302 as the lead screw 302 rotates. The drive source unit 300 is mounted on the second fixed cylinder 11 with the axis of the lead screw 302 approximately parallel to the optical axis OA.

[0042] In this embodiment, a portion 116 of a second fixing cylinder 11 exists between the lead screw 302 and the lens holding frame F2. The outer peripheral surface of the portion 116 of the second fixing cylinder 11 is positioned opposite the lead screw 302, serving as a cover for the lead screw 302. This prevents dust and other contaminants generated on the lead screw 302 from adhering to the lens assembly L2, etc.

[0043] To connect the straight-in member 303, which engages with the lead screw 302 disposed on the outside of the second fixed cylinder 11, and the lens holding frame F2 disposed on the inside of the second fixed cylinder 11, an opening 115 is formed on the second fixed cylinder 11 at a position opposite to the lead screw 302. By inserting the straight-in member 303 through this opening 115, the straight-in member 303, which engages with the lead screw 302, can be connected to the lens holding frame F2.

[0044] like Figure 3 As shown, a mounting member 304 is fixed to the stepper motor 301. A hole 304a is formed in the mounting member 304. The mounting member 304 is mounted to the second fixed cylinder 11 through the hole 304a by screws 305 or the like, thereby fixing the stepper motor 301 to the second fixed cylinder 11.

[0045] The output shaft of the stepper motor 301 is connected to the first end 302a of the lead screw 302 via a connector mechanism 400. Through the connector mechanism 400, the rotational force of the output shaft of the stepper motor 301 is transmitted to the lead screw 302. The structure of the connector mechanism 400 will be described later.

[0046] Figure 4 (B) is an enlarged view of the vicinity of the first end 302a of the lead screw 302. The first end 302a of the lead screw 302 includes a cylindrical portion 302d and a flat portion 302c having mutually generally parallel planes 302f. The diameter of the lead screw 302 is larger than the diameter of the output shaft 301a of the stepper motor 301 (see reference). Figure 12 (A) andFigure 12 Therefore, compared to the output shaft 301a, it is easier to form a flat portion 302c.

[0047] like Figure 4 As shown in (A), the cylindrical portion 302d of the lead screw 302 engages with the inner ring of the bearing 306. The outer ring of the bearing 306 engages with the inner wall of the first hole 112 formed in the second fixed cylinder 11. This allows the lead screw 302 to be supported for rotation and reduces the frictional resistance during rotation. Consequently, the load applied to the stepper motor 301 can be reduced.

[0048] The outer ring of bearing 306 has a flange portion 306a that protrudes radially outward from the outer ring. The flange portion 306a contacts the periphery of the first hole portion 112 of the second fixed cylinder 11. The flange portion 306a is held between the first spring bearing member 307a (described later) and the second fixed cylinder 11. This prevents bearing 306 from falling out of the first hole portion 112.

[0049] In addition, such as Figure 4 As shown in (A), the second end 302b of the lead screw 302 engages with the inner ring of the bearing 311. The outer ring of the bearing 311 engages with the inner wall of the second hole 113 formed in the second fixed cylinder 11. This allows the lead screw 302 to be supported for rotation and reduces the frictional resistance during rotation. Consequently, the load applied to the stepper motor 301 can be reduced.

[0050] like Figure 4 As shown in (A), the outer ring of the bearing 311 has a flange portion 311a that protrudes radially outward from the outer ring. The flange portion 311a contacts the periphery of the second hole portion 113 of the second fixed cylinder 11. Furthermore, the flange portion 311a of the outer ring of the bearing 311 contacts the protrusion 312a of the fixing member 312. Figure 3 As shown, a hole is formed in the fixing member 312, and the fixing member 312 is fixed to the second fixing cylinder 11 through the hole by screws 313 or the like. As a result, the flange portion 311a of the outer ring of the bearing 311 is held between the second fixing cylinder 11 and the fixing member 312, thus preventing the bearing 311 from falling out of the second hole portion 113.

[0051] Additionally, the drive source unit 300 includes a loosening elimination mechanism 307. The loosening elimination mechanism 307 includes a compression spring 307b, a first spring-bearing member 307a contacting one end of the compression spring 307b, and a second spring-bearing member 307c contacting the other end of the compression spring 307b. Figure 4 As shown in (A), the cylindrical portion 302d of the lead screw 302 is inserted into the first spring bearing member 307a, the compression spring 307b, and the second spring bearing member 307c.

[0052] The side of the second spring bearing member 307c opposite to the surface that contacts the compression spring 307b contacts the lead screw 302. More specifically, the side of the second spring bearing member 307c opposite to the surface that contacts the compression spring 307b contacts the step 302e between the threaded portion 302s and the first end 302a in the lead screw 302.

[0053] The surface opposite to the surface of the first spring-supporting member 307a that contacts the compression spring 307b contacts the inner ring of the bearing 306. The compression spring 307b is positioned between the first spring-supporting member 307a and the second spring-supporting member 307c, thus the inner ring of the bearing 306 is subjected to force by the first spring-supporting member 307a in the direction indicated by arrow AR2. Furthermore, the inner ring of the bearing 311 is subjected to force in the direction indicated by arrow AR1 via the second spring-supporting member 307c and the lead screw 302. Therefore, axial loosening caused by axial internal clearance can be suppressed in both bearings 306 and 311.

[0054] Next, the structure of the straight-line member 303, which moves along the axis AX1 of the lead screw 302 as the lead screw 302 rotates, will be described. The axis AX1 is the central axis of the lead screw 302.

[0055] Figure 5 (A) is the front view of the straight-in member 303. Figure 5 (B) is a perspective view of the straight-in member 303. Figure 5 (C) and Figure 5 (D) is an exploded perspective view of the straight-in member 303. Figure 6 This is a sectional view of the straight-in member 303.

[0056] like Figure 5 (C) and Figure 5 As shown in (D), the straight-in member 303 has a main body 31 and a lead screw engagement part 30.

[0057] The main body 31 includes a holding part 31a that holds the lead screw engagement part 30 (described later) and a connecting part 31b that connects to the lens holding frame F2. In this embodiment, the main body 31 is made of resin.

[0058] The lead screw engagement part 30 includes an annular member 32 (fitting part), bearings 33a and 33b, a cover part 34, and a screw 37.

[0059] like Figure 6As shown, a groove 321 is formed on the inner circumference of the annular member 32 to contact the threaded groove of the lead screw 302. In this embodiment, the groove 321 is a circumferential groove formed covering the entire circumference of the inner circumference of the annular member 32, but it is not limited thereto. The groove 321 can be formed on a portion of the inner circumference of the annular member 32 as long as it can contact the threaded groove of the lead screw 302. For example, the groove 321 can also be formed on half of the inner circumference of the annular member 32 (e.g., in a C-shape).

[0060] The outer periphery of the annular member 32 engages with the inner rings of bearings 33a and 33b. Bearings 33a and 33b are arranged such that a protrusion 32a (a portion of the annular member 32) formed on the outer periphery of the annular member 32 is sandwiched between their respective inner rings. The outer rings of bearings 33a and 33b engage with the inner wall of the retaining portion 31a of the main body 31. Thus, the annular member 32 is rotatably held in the main body 31 (straight-in member 303). Furthermore, in this embodiment, the protrusion 32a is continuously provided in the circumferential direction of the annular member 32, but multiple (two or more) protrusions 32a may also be provided separately in the circumferential direction. Alternatively, the protrusion 32a may be provided only in a portion of the circumferential direction of the annular member 32.

[0061] like Figure 6 As indicated by arrow AR6, the annular member 32 is forced towards the lead screw 302 by the second force-applying mechanism 36, which will be described later. Since the annular member 32 is supported to rotate, when the lead screw 302 rotates, the annular member 32 is pressed against the toothed side of the threaded groove of the lead screw 302 and moves in the AX1 direction of the lead screw 302 while rotating. Consequently, the main body 31, which has a holding portion 31a for holding the annular member 32, also moves in the AX1 direction of the lead screw 302, thus enabling the straight-line member 303 to move in a direction parallel to the optical axis OA. That is, the direction of movement of the straight-line member 303 (the AX1 direction) is approximately parallel to the optical axis OA.

[0062] Furthermore, since the annular member 32 rotates while moving along the AX1 axis of the lead screw 302, the friction generated between the annular member 32 and the lead screw 302 becomes rolling friction. This reduces the load applied to the stepper motor 301 when the linear guide member 303 moves along the AX1 axis of the lead screw 302. The structure of the groove 321 in the annular member 32 and the structure of the threaded groove in the lead screw 302 can be applied to the structure disclosed in International Publication No. 2023 / 048093.

[0063] In addition, such as Figure 6 As shown, in the direction of force application of the second force application mechanism 36, the annular member 32 is parallel to the lead screw 302, but in directions other than the direction of force application of the second force application mechanism 36, such as... Figure 4As shown in (A), the annular member 32 is inclined in accordance with the inclination of the teeth (thread grooves) of the lead screw 302. Therefore, as also described in International Publication No. 2023 / 048093, the posture of the annular member 32 relative to the lead screw 302 is stably maintained. Furthermore, the frictional resistance between the lead screw 302 and the annular member 32 can be reduced. Additionally, the annular member 32 can be parallel to the lead screw 302 in directions other than the force application direction of the second force application mechanism 36.

[0064] In this embodiment, the annular member 32 is made of resin. This reduces the drive noise when the annular member 32 is pressed by the toothed side of the threaded groove of the lead screw 302 and moves in the axial AX1 direction of the lead screw 302 while rotating.

[0065] The cover 34 is fixed to the main body 31 by screws 37. For example... Figure 5 As shown in (C), the cover 34 is annular, as... Figure 6 As shown, the cover 34 contacts the outer ring of the bearing 33b, but not the inner ring. Therefore, the outer ring of the bearing 33b will not rotate with the rotation of the lead screw 302, but the inner ring can rotate.

[0066] Here, the reasons for the annular member 32 having a protrusion 32a, the reasons for the two bearings 33a and 33b being arranged to clamp the protrusion 32a, and the reasons for the cover 34, which contacts the outer ring of the bearing 33b, being fixed to the main body 31 will be explained. Figure 7 (A) is a cross-sectional view showing the case where the cover 34 is not fixed to the main body 31.

[0067] In this embodiment, the main body 31 is made of resin. Therefore, as... Figure 7 As shown in (A), when the cover 34 is not fixed to the main body 31, if the bearings 33a and 33b are only fitted with the inner wall of the retaining portion 31a of the main body 31, the retaining force of the main body 31 in holding the bearings 33a and 33b is insufficient. Upon impact, the bearings 33a and 33b may move in the direction indicated by arrow AR3; for example, the bearing 33b may detach from the retaining portion 31a. Therefore, in this embodiment, by providing the cover 34 that contacts the outer ring of the bearing 33b, the rotation of the bearing 33b is not hindered, preventing the bearing 33b from detaching from the retaining portion 31a. That is, the cover 34 maintains the position of the bearings 33a and 33b in the axial AX1 direction.

[0068] Figure 7 (B) is a cross-sectional view of the annular member 132, representing the comparative example. Figure 7 As shown in (B), the annular member 132 does not have a protrusion 32a. Furthermore, the annular member 132 of the comparative example is also made of resin, just like the annular member 32 of this embodiment. Figure 7In (B), a cover 34 is provided that contacts the outer ring of the bearing 33b.

[0069] In this case, if the annular member 132 is only pressed into the inner rings of bearings 33a and 33b and the outer circumference of the annular member 132 is fitted with the inner rings of bearings 33a and 33b, the retaining force of bearings 33a and 33b holding the annular member 132 is insufficient. When subjected to impact, the annular member 132 may move in the direction of arrow AR4 and may fall off bearings 33a and 33b.

[0070] Therefore, in this embodiment, bearings 33a and 33b are arranged to clamp a portion (protrusion 32a) of the annular member 32. Thus, in Figure 6 Even when the annular member 32 is subjected to force in the direction of arrow AR5, the protrusion 32a remains in contact with the bearing 33b, which is maintained in the axial AX1 direction by the cover portion 34. Therefore, the annular member 32 cannot move in the axial AX1 direction. Thus, it is possible to prevent the annular member 32 from detaching from the bearings 33a and 33b.

[0071] exist Figure 3 As shown by the arrow with a single dotted line, the straight-through member 303 is connected to the lens holding frame F2 by housing the connecting part 31b of the main body part 31 in the housing part 210 of the lens holding frame F2.

[0072] Figure 8 (A) is a diagram showing the state before the connecting part 31b of the main body 31 is housed in the receiving part 210 of the lens holding frame F2. Figure 8 (B) is a diagram showing the state in which the connecting part 31b of the main body 31 is housed in the receiving part 210 of the lens holding frame F2. Figure 9 yes Figure 8 (B) AA line section view.

[0073] like Figure 6 and Figure 9 As shown, a first force-applying mechanism 35 and a second force-applying mechanism 36 are installed on the connecting part 31b of the main body 31.

[0074] The first force-applying mechanism 35 includes a compression spring 35a and a spring-bearing part 35b. For example... Figure 9As shown, one end of the compression spring 35a contacts the main body 31, and the other end of the compression spring 35a is held in the spring receiving portion 35b. The surface 351 of the spring receiving portion 35b opposite to the surface that contacts the compression spring 35a contacts the inner wall of the receiving portion 210 of the lens holding frame F2. That is, the spring receiving portion 35b is disposed between the compression spring 35a and the lens holding frame F2, and abuts against the lens holding frame F2. As indicated by arrow AR11, the main body 31 is subjected to force by the compression spring 35a toward the inner wall of the receiving portion 210 of the lens holding frame F2. In other words, the compression spring 35a exerts force on the main body 31 (the straight-in member 303) in a direction parallel to the optical axis OA. Therefore, in the direction parallel to the optical axis OA, the loosening between the main body 31 and the receiving part 210 of the lens holding frame F2 is suppressed. When the straight-in member 303 moves along the axis AX1 of the lead screw 302 as the lead screw 302 rotates, the lens holding frame F2 also moves in the direction of axis AX1 (the direction parallel to the optical axis OA).

[0075] The second force-applying mechanism 36 includes a compression spring 36a and a spring-bearing part 36b. For example... Figure 9 As shown, the compression spring 36a is housed within a spring receiving portion 31d formed in the connecting portion 31b of the main body 31. One end of the compression spring 36a contacts the main body 31, and the other end contacts the spring receiving portion 36b. The surface 361 of the spring receiving portion 36b opposite to the surface that contacts the compression spring 36a contacts the bottom wall of the receiving portion 210. That is, the spring receiving portion 36b is disposed between the compression spring 36a and the lens holding frame F2, and abuts against the lens holding frame F2. As indicated by arrow AR12, the main body 31 is subjected to force toward the lead screw 302 in a direction orthogonal to the axis AX1 of the lead screw 302 by means of the compression spring 36a.

[0076] Furthermore, in this embodiment, such as Figure 8 As shown in (B), the straight-through member 303 is housed in the receiving portion 210 in such a manner that the longitudinal direction of the straight-through member 303 is approximately orthogonal to the radial direction of the lens holding frame F2. Therefore, in this embodiment, the compression spring 36a applies a circumferential force to the main body portion 31 (straight-through member 303) toward the lens holding frame F2.

[0077] As a result, the annular member 32 held by the retaining part 31a of the main body 31 is forced toward the lead screw 302, and the groove 321 of the annular member 32 is pressed into the thread groove of the lead screw 302, thereby suppressing the loosening between the annular member 32 and the lead screw 302.

[0078] Furthermore, in this embodiment, two first force-applying mechanisms 35 are provided, but the number of first force-applying mechanisms 35 can be one or more. Additionally, one second force-applying mechanism 36 is provided, but the number of second force-applying mechanisms 36 can also be two or more.

[0079] In this embodiment, the spring receiving portion 35b of the first force-applying mechanism 35 and the spring receiving portion 36b of the second force-applying mechanism 36 are made of resin. In the first force-applying mechanism 35, the other end of the compression spring 35a contacts the spring receiving portion 35b, and the surface 351 of the spring receiving portion 35b contacts the inner wall of the receiving portion 210 of the lens holding frame F2. As a result, compared to the case where the other end of the compression spring 35a is in direct contact with the inner wall of the receiving portion 210 of the lens holding frame F2, the frictional force generated with the inner wall of the receiving portion 210 in a direction orthogonal to the force-applying direction of the compression spring 35a (e.g., the direction indicated by arrow AR11) is reduced. Therefore, compared to the case where the other end of the compression spring 35a is in direct contact with the inner wall of the receiving portion 210 of the lens holding frame F2, it is possible to prevent the transmission of the force applied by the second force-applying mechanism 36 to the main body 31 toward the lead screw 302 from being hindered.

[0080] Furthermore, in the second force-applying mechanism 36, the other end of the compression spring 36a contacts the spring bearing portion 36b, and the surface 361 of the spring bearing portion 36b contacts the bottom wall of the receiving portion 210 of the lens holding frame F2. Therefore, compared to the case where the other end of the compression spring 36a is in direct contact with the bottom wall of the receiving portion 210 of the lens holding frame F2, the frictional force generated with the bottom wall of the receiving portion 210 in a direction orthogonal to the force-applying direction of the compression spring 36a (e.g., the direction shown by arrow AR12) is reduced. Thus, compared to the case where the other end of the compression spring 36a is in direct contact with the bottom wall of the receiving portion 210 of the lens holding frame F2, it is possible to prevent the transmission of the force applied by the first force-applying mechanism 35 to the main body 31 toward the lens holding frame F2 from being hindered.

[0081] [Connector Mechanism 400]

[0082] When the output shaft of the stepper motor 301 is directly connected to the lead screw 302, if the output shaft of the stepper motor 301 and the shaft AX1 of the lead screw 302 are not collinear, the load applied to the stepper motor 301 will increase due to the offset of the shaft center. In addition, the driving noise of the drive source unit 300 may also increase.

[0083] To allow for shaft offset and transmit the rotational force of the stepper motor 301 to the lead screw 302, a cross-slider coupling could be considered, for example. However, typical cross-slider couplings are space-consuming and cannot be driven unless the motor has a relatively large torque. Alternatively, an adjustment mechanism could be considered to adjust the position of the output shaft of the stepper motor 301 and the position of the shaft AX1 of the lead screw 302, but this would incur adjustment time.

[0084] Therefore, in this embodiment, the connection between the output shaft of the stepper motor 301 and the lead screw 302 is achieved using a connector mechanism 400.

[0085] Figure 10 (A) is a perspective view showing the state in which the lead screw 302 and the output shaft of the stepper motor 301 are connected by the connector mechanism 400. Figure 10 (B) and Figure 10 (C) is a perspective view of the connector mechanism 400. Figure 11 (A) and Figure 11 (B) is a perspective view showing the connector mechanism 400 and the stepper motor 301. Figure 12 (A) and Figure 12 (C) is a diagram showing the output shaft of the lead screw 302 and the stepper motor 301 not connected by the connector mechanism 400. Figure 12 (B) and Figure 12 (D) is a diagram showing the state in which the lead screw 302 and the output shaft of the stepper motor 301 are connected by the connector mechanism 400.

[0086] The joint mechanism 400 includes a first component 41 and a second component 42. For example... Figure 10 As shown in (B), a hole 411 is formed in the first member 41. Figure 11 As shown in (A), the first member 41 is fixed to the output shaft 301a of the stepper motor 301 by pressing the output shaft 301a of the stepper motor 301 into the hole 411.

[0087] The second member 42 has a first groove 421 (see reference) that engages with the first end 302a (more specifically, the flat portion 302c) of the lead screw 302. Figure 10 (C)) and the second groove 422 that engages with the first member 41 (for example, refer to Figure 11 (B)). Furthermore, in Figure 10 (A) Figure 12 In (D), the direction parallel to the axial direction of the lead screw 302 is defined as the Z1 direction, the extension direction of the second groove 422 is defined as the X1 direction, and the direction orthogonal to both the X1 and Z1 directions is defined as the Y1 direction. That is, when the lead screw 302 is configured such that its axial direction is parallel to the optical axis OA, the Z1 direction is the direction parallel to the optical axis OA.

[0088] like Figure 11 As shown in (B), the second groove 422 extends along the X1 direction and has a T-shape when viewed from the X1 direction. When viewed from the X1 direction, the first member 41 has a T-shape that engages with the second groove 422. Figure 12 As shown in (B), the first member 41 and the second slot 422 are engaged in a manner in which relative movement in the Y1 direction is restricted. Therefore, when the first member 41 is engaged with the second member, although the second member 42 is allowed to move relative to the first member 41 in the X1 direction (first direction), its movement relative to the first member 41 in the Y1 direction (second direction) is restricted.

[0089] like Figure 10 As shown in (C), when viewed from the Z1 direction (in the X1Y1 plane), the first groove 421 of the second member 42 is an I-shaped groove extending in the Y1 direction (second direction). In this embodiment, the width (thickness) of the flat portion 302c of the lead screw 302 in the X1 direction is approximately the same as or slightly smaller than the width of the first groove 421 in the X1 direction. Furthermore, the length of the first groove 421 of the second member 42 in the Y1 direction is greater than the width of the flat portion 302c of the lead screw 302 in the Y1 direction. Therefore, the second member 42 can move relative to the lead screw 302 in the Y1 direction (second direction) (movement in the Y1 direction is permitted), but is restricted from moving relative to the lead screw 302 in the X1 direction (first direction) (movement in the X1 direction is not permitted).

[0090] The second member 42 is restricted from moving in the Y1 direction relative to the first member 41 fixed to the output shaft 301a of the stepper motor 301, and is restricted from moving in the X1 direction relative to the lead screw 302. Therefore, the rotational force of the output shaft 301a of the stepper motor 301 can be transmitted to the lead screw 302. Furthermore, the second member 42 can move relative to the first member 41 in the X1 direction and relative to the lead screw 302 in the Y1 direction. Thus, even when the output shaft 301a of the stepper motor 301 and the axis AX1 of the lead screw 302 are not collinear, the oscillation of the second member 42 can absorb the axis offset. This suppresses the application of excessive load to the stepper motor 301 and also suppresses noise generation.

[0091] Furthermore, a typical cross-slider coupling comprises three components: two hub members fixed to the output shaft of the stepper motor 301 and the lead screw 302, respectively, and a sliding member disposed between the two hub members. The joint mechanism 400 of this embodiment consists of only two components, thus reducing the space required for the joint compared to a typical cross-slider coupling. Therefore, even when using the joint mechanism 400, space in the drive source unit 300 can be saved.

[0092] Furthermore, the length of the lead screw 302 is longer than the length of the output shaft 301a and the lengths of the first member 41 and the second member 42 in the optical axis OA direction. Therefore, even when the shaft AX1 of the lead screw 302 is configured at a slight inclination relative to the optical axis OA, the offset of the position of the first end 302a of the lead screw 302 from the designed position becomes larger. In this embodiment, even when the position of the first end 302a of the lead screw 302 deviates from the designed position, the deviation of the axis can be absorbed by the joint mechanism 400.

[0093] The assembly sequence of the connector mechanism 400 is as follows. First, the output shaft 301a of the stepper motor 301 is pressed into the hole 411 formed in the first member 41, and the first member 41 is fixed to the output shaft 301a of the stepper motor 301. Next, the first member 41 is slid to engage with the second groove 422 of the second member 42, so that the first member 41 and the second member 42 can move relative to each other in the X1 direction (first direction).

[0094] With the first component 41 and the second component 42 engaged (with the connector mechanism 400 installed on the stepper motor 301), after the stepper motor 301 is installed on the second fixed cylinder 11, the flat portion 302c of the lead screw 302 is inserted into the first groove 421 of the second component 42 in such a way that the flat portion 302c of the lead screw 302 and the second component 42 can move relative to each other in the Y1 direction (second direction).

[0095] The sequence for fixing the drive source unit 300 to the second fixed cylinder 11 is as follows. First, the lead screw 302, together with the fixing member 312, bearings 306 and 311, and loosening elimination mechanism 307, is rotatably mounted to the second fixed cylinder 11. Next, the stepper motor 301, on which the connector mechanism 400 is mounted, is mounted to the second fixed cylinder 11. At this time, the lead screw 302 is rotated such that the flat portion 302c of the lead screw 302 can be inserted into the first slot 421 of the second member 42 of the connector mechanism 400. In this embodiment, the lead screw 302 is positioned on the outside rather than the inside of the second fixed cylinder 11, thus facilitating the operation of rotating the lead screw 302 to engage the flat portion 302c with the first slot 421 of the second member 42.

[0096] After engaging the flat portion 302c of the lead screw 302 with the first groove 421 of the second member 42, the stepper motor 301 is fixed to the second fixed cylinder 11. In this way, the drive source unit 300 can be fixed to the second fixed cylinder 11.

[0097] As detailed above, according to this embodiment, the lens barrel 100 includes: a lens holding frame F2 for holding the lens group L2; a lead screw 302 that rotates via a stepper motor 301; an annular member 32 that moves in the AX1 direction corresponding to the rotation of the lead screw 302 about the AX1 axis; a plurality of bearings 33a and 33b that clamp a portion of the annular member 32; and a straight-through member 303 connected to the lens holding frame F2, which holds the annular member 32 in a rotatable manner via the plurality of bearings 33a and 33b, and moves in the AX1 direction as the annular member 32 moves in the AX1 direction. Since the bearings 33a and 33b clamp a portion of the annular member 32, even if the annular member 32 is made of resin for noise reduction, it is possible to prevent the annular member 32 from falling off the bearings 33a or 33b due to impact or the like.

[0098] Furthermore, in this embodiment, the annular member 32 has a protrusion 32a sandwiched between multiple bearings 33a and 33b, and the positions of the multiple bearings 33a and 33b relative to the straight-through member 303 (main body 31) in the axial AX1 direction are maintained. This prevents the bearings 33a and 33b from detaching from the retaining portion 31a of the main body 31 and the annular member 32 from detaching from the bearings 33a or 33b due to impacts or the like.

[0099] Furthermore, in this embodiment, the inner rings of the plurality of bearings 33a and 33b are integrated with the annular member 32 and rotate as the lead screw 302 rotates. As a result, the annular member 32 moves along the axis AX1 of the lead screw 302 while rotating, thus the friction generated between the annular member 32 and the lead screw 302 becomes rolling friction, which reduces the load applied to the stepper motor 301 when the linear feed member 303 moves in a direction parallel to the axis AX1 of the lead screw 302.

[0100] Furthermore, in this embodiment, the straight-through member 303 has a cover portion 34, and the outer ring of one of the plurality of bearings 33a and 33b abuts against the cover portion 34 and does not rotate with the rotation of the lead screw 302. Therefore, the rotation of the bearing 33b is not hindered, and the bearing 33b is prevented from falling off the retaining portion 31a.

[0101] Furthermore, according to this embodiment, the lens barrel 100 includes: a lead screw 302, which rotates via a stepper motor 301; a straight-line member 303, which moves along the lead screw 302 when the lead screw 302 rotates; a lens holding frame F2, which is connected to the straight-line member 303 and moves with the straight-line member 303; a plurality of compression springs 35a and 36a, one end of which contacts the straight-line member 303 and applies force to the straight-line member 303 in a different direction relative to the lens holding frame F2; and spring receiving portions 35b and 36b, which are disposed between the other end of each of the plurality of compression springs 35a and 36a and the lens holding frame F2, and abut against the lens holding frame F2. Therefore, compared to the case where the compression springs 35a and the lens holding frame F2 are in direct contact, the frictional force between the compression springs 35a and the lens holding frame F2 in a direction orthogonal to the direction of the applied force of the compression springs 35a is reduced, thus preventing the transmission of the force of the compression springs 36a from being hindered. Furthermore, compared to the case where the compression spring 36a and the lens holding frame F2 are in direct contact, the frictional force between the compression spring 36a and the lens holding frame F2 in the direction orthogonal to the force direction of the compression spring 36a is reduced, thus preventing the transmission of the force of the compression spring 35a from being hindered.

[0102] Furthermore, according to this embodiment, the drive source unit 300 includes: a first member 41 fixed to the output shaft 301a of the stepper motor 301; a lead screw 302 having a threaded groove, and its shaft AX1 being arranged substantially parallel to the output shaft 301a; and a second member 42 engaging with the first member 41 at one end and engaging with the first end 302a of the lead screw 302 at the other end. The second member 42 is allowed to move relative to the first member 41 in the X1 direction orthogonal to the output shaft 301a, and is restricted from moving relative to the first member 41 in the Y1 direction, which is substantially orthogonal to the X1 direction. The second member 42 is allowed to move relative to the lead screw 302 in the Y1 direction, and is restricted from moving relative to the lead screw 302 in the X1 direction. Because the second member 42 is restricted from moving relative to the first member 41 in the Y1 direction and from moving relative to the lead screw 302 in the X1 direction, the rotational force of the output shaft 301a of the stepper motor 301 can be transmitted to the lead screw 302. Furthermore, the second component 42 is movable relative to the first component 41 in the X1 direction and relative to the lead screw 302 in the Y1 direction. Therefore, even if the output shaft 301a of the stepper motor 301 and the shaft AX1 of the lead screw 302 are not collinear, the second component 42 can still oscillate and absorb the offset of the shaft center. This suppresses excessive load on the stepper motor 301 and also suppresses noise generation. In addition, the number of components constituting the joint mechanism 400 is two, fewer than that of a typical cross-slider coupling, thus achieving space saving and space saving for the drive source unit 300.

[0103] Furthermore, in the above embodiment, the annular member 32 is made of resin, but if the annular member 32 is made of metal, a structure in which bearings 33a and 33b clamp a portion of the annular member 32 can also be used.

[0104] Alternatively, in the above embodiment, the first component 41 of the connector mechanism 400 is fixed to the output shaft 301a of the stepper motor 301, but the first component 41 can also be fixed to the lead screw 302. In this case, a flat portion is formed on the output shaft 301a of the stepper motor 301, and this flat portion engages with the first groove 421 of the second component 42, so that the first component 41 fixed to the lead screw 302 engages with the second groove 422 of the second component 42.

[0105] In addition, in the above embodiment, a second groove 422 that engages with the first member 41 is formed in the second member 42 of the connector mechanism 400, but a groove that engages with the second member 42 and extends along the X1 direction may also be formed in the first member 41.

[0106] (Variation Example 1)

[0107] Figure 13 (A) Figure 13 (D) is a diagram used to illustrate the joint mechanism 400A of Modified Example 1. Figure 13 (A) is a perspective view showing the state in which the lead screw 302A is connected to the output shaft 301a of the stepper motor 301 via the connector mechanism 400A. Figure 13 (B) is a perspective view illustrating the structure of the connector mechanism 400A. Figure 13 (C) and Figure 13 (D) is a diagram showing the state of the output shaft 301a of the lead screw 302A and the stepper motor 301 connected by the connector mechanism 400A.

[0108] like Figure 13 (A) Figure 13 As shown in (D), the joint mechanism 400A has a first component 41A and a second component 42A.

[0109] The second component 42A has a guide groove 422A and an engaging portion 427. Figure 13 (A) Figure 13 In (D), the direction parallel to the axis of the lead screw 302A is set as the Z3 direction, the extension direction of the guide groove 422A is set as the X3 direction, and the direction orthogonal to the X3 and Z3 directions is set as the Y3 direction.

[0110] like Figure 13 (B) and Figure 13 As shown in (C), the guide groove 422A of the second component 42A extends along the X3 direction, as... Figure 13As shown in (C), it has a T-shape when viewed from the X3 direction. Figure 13 As shown in (B), the first member 41A has a side portion 412 that is orthogonal to the Y3 direction and extends along the X3 direction, which engages with the guide groove 422A of the second member 42A. Figure 13 As shown in (C), the first member 41A engages with the guide groove 422A in a manner that prevents relative movement in the Y3 direction. Thus, the second member 42A is allowed to move relative to the first member 41A in the X3 direction (movement in the X3 direction is permitted), and is restricted from moving relative to the first member 41A in the Y3 direction (movement in the Y3 direction is not permitted).

[0111] In addition, such as Figure 13 As shown in (B), the engaging portion 427 of the second member 42A has a side surface 427a that is orthogonal to the X3 direction and extends along the Y3 direction. Figure 13 (B) and Figure 13 As shown in (D), in modified example 1, a groove 302h is formed at the front end of the first end 302a of the lead screw 302A. When viewed from the -Z3 direction (in the Z3Y3 plane), the groove 302h extends along the Y3 direction. The engaging portion 427 of the second member 42A is inserted into the groove 302h of the lead screw 302A. Figure 14 As shown in (D), the groove 302h of the lead screw 302A engages with the engagement portion 427 of the second member 42A in a manner that prevents relative movement in the X3 direction. Therefore, the second member 42A is allowed to move relative to the lead screw 302A in the Y3 direction (movement in the Y3 direction is permitted), but its movement relative to the lead screw 302A in the X3 direction is restricted (movement in the X3 direction is not permitted).

[0112] The second member 42A is restricted from moving in the Y3 direction relative to the first member 41A fixed to the output shaft 301a of the stepper motor 301, and is restricted from moving in the X3 direction relative to the lead screw 302A. Therefore, the rotational force of the output shaft 301a of the stepper motor 301 can be transmitted to the lead screw 302A. Furthermore, the second member 42A is allowed to move in the X3 direction relative to the first member 41A, and is also allowed to move in the Y3 direction relative to the lead screw 302A. Thus, even if the axes of the output shaft 301a of the stepper motor 301 and the lead screw 302A are not collinear, the axial offset can be absorbed by the swinging of the second member 42A. This suppresses the application of excessive load to the stepper motor 301 and reduces noise generation. Additionally, in Modification 1, the number of members constituting the joint mechanism 400A is also two, thus reducing the space required for the joint mechanism 400A compared to a typical cross-slider coupling.

[0113] As shown in Modified Example 1, the groove extending along the Y3 direction can also be provided on the lead screw instead of the second component.

[0114] (Variation Example 2)

[0115] Figure 15 (A) to Figure 14 (C) is a diagram used to illustrate the joint mechanism 400B of modified example 2. Figure 14 (A) is a perspective view showing the state in which the lead screw 302B is connected to the output shaft 301a of the stepper motor 301 via the connector mechanism 400B. Figure 14 (B) is a perspective view used to illustrate the structure of the joint mechanism 400B. Figure 14 (C) and Figure 15 (D) is a diagram representing the second component 42B. Additionally, Figure 15 (A) and Figure 15 (B) is a sectional view used to illustrate the connection relationship between the lead screw 302B, the connector mechanism 400B, and the output shaft 301a. Figure 14 (C) is an enlarged view of the first end 302a of the lead screw 302B.

[0116] like Figure 14 As shown in (B), the joint mechanism 400B has a first component 41B and a second component 42B.

[0117] The second component 42B has an elongated hole 423 (see reference). Figure 14 (C) and hole 425 (refer to) Figure 14 (D)). In Figure 14 (A) Figure 14 In (D), the direction parallel to the axis of the lead screw 302B is set as the Z2 direction, the extension direction of the elongated hole 423 is set as the Y2 direction, and the direction orthogonal to the Y2 direction and the Z2 direction is set as the X2 direction.

[0118] like Figure 14 As shown in (C), two protrusions 424 opposing each other in the X2 direction are formed within the elongated hole 423. Furthermore, as... Figure 15 As shown in (D), two wall portions 426 that are opposite to and substantially parallel in the Y2 direction are provided inside the hole portion 425.

[0119] The first member 41B has side surfaces 413 that are opposite each other in the Y2 direction and are approximately orthogonal to the Y2 direction. The first member 41A is inserted between the two wall portions 426 such that its side surface 413 is opposite to the wall portion 426 of the second member 42B. The diameter of the hole portion 425 is set to be larger than the maximum length of the first member 41A in the X2 direction. Thus, the second member 42B is allowed to move relative to the first member 41B in the X2 direction, but is restricted to move relative to the first member 41B in the Y2 direction (movement is not allowed).

[0120] like Figure 15 (B) and Figure 16 As shown in (C), a recess 302g is formed at the first end 302a of the lead screw 302B. The recess 302g is disposed between the protrusions 424 formed within the elongated hole 423 of the second member 42B. Thus, the second member 42B is allowed to move relative to the lead screw 302B in the Y2 direction, and is restricted to move relative to the lead screw 302B in the X2 direction (movement is not allowed).

[0121] The second member 42B is restricted from moving in the Y2 direction relative to the first member 41B fixed to the output shaft 301a of the stepper motor 301, and is restricted from moving in the X2 direction relative to the lead screw 302B. Therefore, the rotational force of the output shaft 301a of the stepper motor 301 can be transmitted to the lead screw 302B. Furthermore, the second member 42B is allowed to move in the X2 direction relative to the first member 41B, and is allowed to move in the Y2 direction relative to the lead screw 302B. Thus, even if the output shaft 301a of the stepper motor 301 and the axis AX1 of the lead screw 302B are not collinear, the axial offset can be absorbed by the swinging of the second member 42B. This suppresses the application of excessive load to the stepper motor 301 and also suppresses noise generation. In addition, in Modification 2, the number of members constituting the joint mechanism 400B is also two, thus reducing the space required for the joint mechanism 400B compared to a conventional cross-slider coupling.

[0122] Second Implementation Method

[0123] The structure of the straight-line member 303 in the drive source unit 300 is not limited to the first embodiment described above. Figure 17 This is a perspective view showing the relationship between the drive source unit 300C, the lens holding frame F2C, and the second fixing cylinder 11C in the second embodiment. Figure 18 This is a perspective view illustrating the structure of the lens holding frame F2C and the drive source unit 300C. Figure 18 (A) is a perspective view of the straight-through member 303C of the second embodiment. Figure 19 (B) is an exploded perspective view of the straight-in member 303. Additionally, Figure 16This is a sectional view used to illustrate the connection between the lens retaining frame F2C and the straight-through member 303C.

[0124] like Figure 19 As shown, the second fixing cylinder 11C in the second embodiment, like in the first embodiment, has an opening 115 formed at a position opposite to the lead screw 302B. This allows connection between the straight-through member 303C and the lens holding frame F2. Furthermore, a portion 116 of the second fixing cylinder 11C exists between the lens holding frame F2C and the lead screw 302B. This portion 116 of the second fixing cylinder 11C is positioned opposite the lead screw 302 in the direction of gravity, functioning as a cover for the lead screw 302. This prevents dust and other contaminants generated by the lead screw 302 from falling into the second fixing cylinder 11C.

[0125] The straight-line member 303C of the second embodiment includes a main body 31C, a lead screw engagement part 30C, and a connecting part 38. The lead screw engagement part 30C includes an annular member 32, bearings 33a and 33b, a cover part 34C, and a screw 37. The lead screw engagement part 30C is held in the holding part 31a of the main body 31C. The structure of the lead screw engagement part 30C is the same as that of the lead screw engagement part 30 of the first embodiment, except for the shape of the cover part 34C, so detailed description is omitted.

[0126] The connecting part 38 includes a connecting member 38a and a screw 38b. The connecting member 38a is fixed to the main body 31C by the screw 38b. ​ As shown, the connecting member 38a is inserted into the receiving portion 210C formed in the lens holding frame F2C. The connecting member 38a has a flange portion 381, and a compression spring 36a is disposed between the flange portion 381 and the lens holding frame F2C. As a result, the main body portion 31C is subjected to force in the direction indicated by arrow AR31, and thus the annular member 32 is pressed against the lead screw 302B. This prevents loosening between the annular member 32 and the lead screw 302B.

[0127] A force-applying mechanism 35C is installed in the lens holding frame F2C to apply force to the inner wall of the connecting member 38a toward the receiving part 210C. The force-applying mechanism 35C includes a compression spring 35a, a spring bearing part 35c, a fixing part 35d, and a screw 35e.

[0128] The fixing part 35d is fixed to the lens holding frame F2C by screws 35e. One end of the compression spring 35a contacts the spring receiving part 35c, and the other end of the compression spring 35a contacts the fixing part 35d. The surface 352 of the spring receiving part 35c opposite to the surface that contacts the compression spring 35a contacts the connecting member 38a.

[0129] The spring receiving part 35c is compressed by the spring 35a in the direction indicated by arrow AR32. As a result, the connecting member 38a is pressed against the inner wall of the receiving part 210C. Therefore, if the straight-through member 303C moves in a direction parallel to the optical axis OA as the lead screw 302B rotates, the lens holding frame F2C also moves in a direction parallel to the optical axis OA.

[0130] Furthermore, in this embodiment, the connecting member 38a and the spring bearing portion 35c are made of resin. Therefore, compared to the case where the compression spring 35a and the connecting member 38a are in direct contact, the frictional force between the compression spring 35a and the lens holding frame F2C in the direction orthogonal to the force applied by the compression spring 35a can be reduced. Thus, compared to the case where the compression spring 35a and the connecting member 38a are in direct contact, the transmission of the force applied by the compression spring 36a to the main body 31C in the direction indicated by arrow AR31 can be prevented from being hindered.

[0131] Furthermore, in the second embodiment, the connector mechanism connecting the lead screw 302B and the output shaft 301a of the stepper motor 301 is the connector mechanism 400B of Modified Example 2, but the connector mechanism 400 of the first embodiment or the connector mechanism 400A of Modified Example 1 may also be used. Other structures are the same as in the first embodiment, so detailed descriptions are omitted.

[0132] Furthermore, in the above embodiments and variations, a stepper motor 301 is used, but it can also be replaced by, for example, an ultrasonic motor.

[0133] Furthermore, in the above embodiments and modifications, a bearing is provided on each side of the protrusion 32a of the annular member 32, but this is not a limitation. For example, one bearing may be provided on one side of the protrusion 32a, and two or more bearings may be provided on the other side. Alternatively, two or more bearings may be provided on each side of the protrusion 32a.

[0134] Furthermore, in the above embodiments and variations, the joint mechanisms 400, 400A, and 400B are constituted by first components 41, 41A, and 41B and second components 42, 42A, and 42B, but are not limited thereto. For example, in the first embodiment, the cylindrical portion 302d of the lead screw 302 and the flat portion 302c having mutually substantially parallel planes 302f may be formed separately, and other components may be arranged between the second component 42 and the cylindrical portion 302d of the lead screw 302, so that the joint mechanism 400 is essentially composed of three components.

[0135] The above-described embodiments are preferred embodiments. However, they are not limited thereto, and various modifications can be implemented without departing from the main idea, and arbitrary structural elements can be combined.

[0136] Label Explanation

[0137] 1 camera

[0138] 11 Second fixed cylinder

[0139] 32 Ring-shaped components

[0140] 32a Protrusion

[0141] 33a and 33b bearings

[0142] 34 cover

[0143] 35 First force-applying mechanism

[0144] 35a Compression Spring

[0145] 35b Spring support part

[0146] 36 Second force-applying mechanism

[0147] 36a Compression Spring

[0148] 36b Spring bearing part

[0149] 41, 41A, 41B First Component

[0150] 42, 42A, 42B Second Components

[0151] 100 lens barrel

[0152] 115 Opening

[0153] 300, 300C drive source unit

[0154] 301 Stepper Motor

[0155] 302, 302A, 302B lead screws

[0156] 303, 303C Straight-in Components

[0157] 400, 400A, 400B Connector Mechanism

Claims

1. A drive mechanism comprising: a first member fixed to an output shaft of a motor; a rotation shaft having a screw groove and arranged with a center axis substantially in parallel with the output shaft; and a second member engaged with the first member at one end side and engaged with one end of the rotation shaft at the other end side, the second member being allowed to move relative to the first member in a first direction orthogonal to the output shaft and being restricted from moving relative to the first member in a second direction substantially orthogonal to the first direction, the second member being allowed to move relative to the rotation shaft in the second direction and being restricted from moving relative to the rotation shaft in the first direction.

2. The drive mechanism according to claim 1, wherein one of the second member and the rotation shaft has a first groove portion at one end portion, the first groove portion extending in the second direction, and the other of the second member and the rotation shaft has a first engagement portion at one end portion, the first engagement portion being engaged with the first groove portion.

3. The drive mechanism according to claim 1 or 2, wherein one of the first member and the second member has a second groove portion at one end portion, the second groove portion extending in the first direction, and the other of the first member and the second member has a second engagement portion at one end portion, the second engagement portion being engaged with the second groove portion.

4. The drive mechanism according to any one of claims 1 to 3, wherein the axes of the output shaft and the rotation shaft are not on one straight line.

5. The drive mechanism according to any one of claims 1 to 4, wherein the diameter of the output shaft is smaller than the diameter of the rotation shaft.

6. The drive mechanism according to any one of claims 1 to 5, wherein the length of the rotation shaft is longer than any one of the length of the output shaft, the length in the optical axis direction of the first member, and the length in the optical axis direction of the second member.

7. A lens barrel comprising: the drive mechanism according to any one of claims 1 to 6; and a lens holding frame engaged with the screw groove of the rotation shaft and driven in the direction in which the rotation shaft extends with rotation of the rotation shaft.

8. The lens barrel according to claim 7, wherein the lens barrel further comprises a barrel member arranged at the outer periphery side of the lens holding frame, and the drive mechanism is fixed to the barrel member.

9. The lens barrel according to claim 8, wherein the barrel member has an opening portion formed at a position opposite to the rotation shaft.

10. The lens barrel according to claim 8, wherein the position at which the rotation shaft is engaged with the second member is located outward in the optical axis direction than the barrel member.

11. The lens barrel according to claim 8, wherein after the first member and the second member are fixed to the barrel member in the engaged state, the motor is capable of engaging the rotation shaft engaged with the lens holding frame with the second member.

12. A lens barrel comprising: a motor having an output shaft and moving a lens holding frame in an optical axis direction; ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ a rotation shaft having a screw groove and disposed substantially in parallel with the output shaft; and an adjustment member disposed between the motor and the rotation shaft to adjust a relative position of a center axis of the output shaft and a center axis of the rotation shaft, the adjustment member has a plurality of members.

13. The lens barrel according to claim 12, wherein the adjustment member has a first member fixed to the output shaft of the motor and a second member engaged with the first member.

14. An imaging device provided with the lens barrel according to any one of claims 7 to 13.

Images