Lens barrel

Abstract

To provide a lens barrel that has a good space efficiency and can suppress transmission of vibration to shake detection means.SOLUTION: A lens barrel has: a stationary barrel; a mount attached to the stationary barrel; an electric contact fixed to the mount; a first substrate arranged between the stationary barrel and the mount; a second substrate connected with the first substrate and the electric contact with a folded part formed thereon and arranged to overlap the first substrate when seen from an optical axis direction; a plurality of first elastic members held on the stationary barrel and positioning and holding the first substrate in an optical axis orthogonal direction; and a second elastic member held on the stationary barrel and arranged between the stationary barrel and the first substrate. The first substrate is urged by force from the folded part toward a side of the stationary barrel in the optical axis direction and in contact with the second elastic member on a surface facing the stationary barrel.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a lens barrel. [Background technology]

[0002] Conventionally, in a lens barrel of an interchangeable lens system capable of image blur correction, a board on which a shake detection means for detecting shake is mounted is positioned and fixed near a mount, which is an attachment part for a camera body. Patent Document 1 discloses a lens barrel that holds the board with an elastic member in order to suppress the transmission of shutter shock vibrations generated when a shutter mechanism in a camera body is driven to the shake detection means. Patent Document 2 discloses a lens barrel that holds the board by pressing it against the mount side with a biasing rubber installed between a fixing part and the board. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5053754 [Patent Document 1] JP 2004-77919 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the lens barrel of Patent Document 1, the substrate is held by at least three elastic members, so three holes or cutouts are required to fit the elastic members, but electrical wiring cannot be installed in the holes or cutouts or their surrounding areas, and electrical components cannot be mounted either. Therefore, the space efficiency is not good, and it is difficult to further reduce the size of the lens barrel.

[0005] Furthermore, in the lens barrel of Patent Document 2, vibrations are transmitted directly to the substrate via the mount, which deteriorates the performance of image stabilization.

[0006] An object of the present invention is to provide a lens barrel that is space-efficient and capable of suppressing the transmission of vibrations to a vibration detection unit. [Means for solving the problem]

[0007] A lens barrel according to one aspect of the present invention includes a fixed barrel, a mount attached to the fixed barrel, electrical contacts fixed to the mount, a first substrate arranged between the fixed barrel and the mount, a second substrate connected to the first substrate and the electrical contacts with a folded portion formed therein and arranged to overlap with the first substrate when viewed along the optical axis, a plurality of first elastic members held by the fixed barrel for positioning and holding the first substrate in a direction perpendicular to the optical axis, and a second elastic member held by the fixed barrel and arranged between the fixed barrel and the first substrate. A shake detection means for detecting shake is mounted on the first substrate, The first substrate is biased toward the fixed barrel in the optical axis direction by a force from the folded portion, and is characterized in that the surface of the first substrate facing the fixed barrel comes into contact with the second elastic member. Effect of the Invention

[0008] According to the present invention, it is possible to provide a lens barrel that is space-efficient and capable of suppressing the transmission of vibrations to a vibration detection means. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of a lens barrel according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing the main components of a lens barrel. [Diagram 3] FIG. 2 is an exploded perspective view of the main components of the lens barrel. [Figure 4] FIG. 2 is a cross-sectional view of the main components of the lens barrel. [Diagram 5] FIG. 5 is a partially enlarged view of FIG. [Figure 6] FIG. 2 is a side view of the main components of the lens barrel. [Figure 7] 2 is a diagram of an electric component mounting board as viewed from the imaging surface side. FIG. [Figure 8] FIG. 4 is an explanatory diagram of a folded portion of a flexible substrate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In each drawing, the same reference numerals are given to the same members, and duplicated explanations will be omitted.

[0011] 1 is a cross-sectional view of a lens barrel (interchangeable lens) 100 according to an embodiment of the present invention. Lens barrel 100 is detachably attached to a camera body (not shown) such as a single-lens reflex camera, a mirrorless camera, or a film camera.

[0012] Lens barrel 100 has a plurality of lens groups. Anti-vibration lens group L moves in a direction including a component perpendicular to optical axis X of lens barrel 100 during image blur correction. Lens barrel 100 may have a focus mechanism, a zoom mechanism, an electric aperture mechanism, or the like. Electrical component mounting board (first board) 1 is an annular printed board on which a control circuit and a shake detection means for detecting shake are mounted, and controls various actuators and electromagnetic aperture 113. The shake detection means is specifically a gyro sensor or an acceleration sensor. The shape of electrical component mounting board 1 may be a C-shape that is connected at least 180° or more (for example, about 240°) in the circumferential direction.

[0013] FIG. 2 is a diagram showing the main components of lens barrel 100. FIG. 2(a) is a perspective view of the main components, and FIG. 2(b) is a view of the main components as viewed from the imaging surface side. FIG. 3 is an exploded perspective view of the main components. FIG. 4 is a cross-sectional view of the main components of lens barrel 100. FIG. 5 is a partially enlarged view of FIG. 4, showing the periphery of elastic member 2. FIG. 6 is a side view of the main components of lens barrel 100 as viewed from the contact terminal block 5 side. FIG. 7 is a view of electrical component mounting board 1 as viewed from the imaging surface side.

[0014] The electric component mounting board 1 is disposed between the fixed cylinder 3 and the mount 4 in the optical axis direction of the lens barrel 100. Cutouts 11 and 12 are provided on the outer periphery of the electric component mounting board 1. An elastic member (first elastic member) 2 is inserted into the cutouts 11 and 12 while elastically deforming. The elastic member 2 is made of a material that is easily elastically deformed, such as silicone rubber.

[0015] The elastic member 2 is provided with a plurality of constrictions 21. The constrictions 21 are configured to sandwich the electric component mounting board 1. Furthermore, a hole 22 is provided in the center of the elastic member 2. A protrusion 31 provided on the fixed barrel 3 is inserted into the hole 22. Therefore, the electric component mounting board 1 is positioned and held in the direction orthogonal to the optical axis by the elastic member 2, and is fixed to the fixed barrel 3.

[0016] The mount 4 is attached to the fixed barrel 3 and compressively holds (presses) the elastic member 2. Therefore, the constricted portion 21 of the elastic member 2 acts as a retainer, and the electric component mounting board 1 is held by the elastic member 2 in a state where it is positioned in the optical axis direction. As a result, external vibrations such as shutter shock vibrations generated when the shutter mechanism in the camera body is driven are absorbed by the elastic member 2 and are not transmitted to the vibration detection means mounted on the electric component mounting board 1. Generally, the mount of an interchangeable lens has a function of connecting the interchangeable lens to the camera body, but the mount 4 of this embodiment does not need to have such a function. For example, it may be a separate part such as a back cover fixed to a general mount to prevent ghosts, flares, etc. caused by harmful light reflected by parts near the mount.

[0017] The contact terminal block (electrical contacts) 5 is immovably fixed to the mount 4 with screws, adhesives, etc., and is electrically connected to the electrical component mounting board 1 via a flexible board (second board) 6, and provides communication with the camera body and power supply.

[0018] Although the contact pins 51 provided on the contact terminal block 5 and the electric component mounting board 1 do not overlap when viewed from the optical axis direction, the distance between them in the direction perpendicular to the optical axis is very narrow. In addition, since solder is piled around the contact pins 51 by soldering to connect the contact pins 51 to the flexible board 6, the distance becomes narrower by the volume of the piled solder. Therefore, there is a risk that the contact pins 51 and the solder around the contact pins 51 may come into contact with the electric component mounting board 1. To avoid such contact, it is necessary to sufficiently separate the electric component mounting board 1 and the contact terminal block 5 in the optical axis direction, but this would increase the overall length of the lens barrel 100 in the optical axis direction.

[0019] In this embodiment, in order to avoid such contact, a small diameter portion 13 having a smaller diameter than other portions is provided at a portion of the outer periphery of the electric component mounting board 1. The small diameter portion 13 occupies approximately one-fourth of the electric component mounting board 1 in the circumferential direction of the electric component mounting board 1. Since the contact pin 51 fits into the small diameter portion 13, the contact terminal block 5 and the flexible board 6 overlap with the electric component mounting board 1 in the optical axis direction. Therefore, it is possible to shorten the overall length of the lens barrel 100 while avoiding contact between the electric component mounting board 1 and the contact terminal block 5.

[0020] In this embodiment, the electric component mounting board 1 and the contact terminal block 5 are connected by inserting the flexible board 6 into the connector 14 (connection portion between the electric component mounting board 1 and the flexible board 6) installed on the electric component mounting board 1. By using the connector 14, it is possible to reduce the size of the electric component mounting board 1, improve the assembly workability, and reduce the assembly cost. The electric component mounting board 1 is provided with a small diameter portion 13, thereby forming a narrow width portion 15 having a narrow radial width. It is difficult to install the connector 14 in the narrow width portion 15 because the radial width is insufficient for the radial width of the connector 14, or even if the width is sufficient, it is not possible to provide a wiring pattern for the connector 14. Therefore, in this embodiment, the connector 14 is installed in an area adjacent to the small diameter portion 13 and with a sufficiently wide radial width, as shown in FIG. 3.

[0021] It is not necessary to use connector 14 when connecting flexible substrate 6 to electric component mounting board 1. For example, flexible substrate 6 may be connected to electric component mounting board 1 by being soldered to a land portion provided on electric component mounting board 1.

[0022] Furthermore, because narrow width portion 15 has a narrow width in the radial direction, it is difficult to provide narrow width portion 15 with a cutout portion for fixing elastic member 2, such as cutout portions 11 and 12. Although it is possible to provide a cutout portion in a region that bridges and connects to the outer periphery of small diameter portion 13, this would cause electric component mounting board 1 to expand toward the outer diameter side, resulting in an increase in the size of lens barrel 100.

[0023] With the folded portion 61 formed, the flexible substrate 6 has a first end connected to the electric component mounting board 1 and a second end connected to the contact terminal block 5. In this embodiment, the first end is inserted into the connector 14. The flexible substrate 6 is disposed so as to overlap with the electric component mounting board 1 when viewed from the optical axis direction. The folded portion 61 is formed in a U-shape in this embodiment, but may be bent. The straight line connecting the center of the folded portion 61 and the center of the optical axis is the same as that of the connector 14 shown in FIG. 7. (Center of connection) and the center of the optical axis as a reference. Note that "approximately ±60 degrees" includes cases where the angle is exactly ±60 degrees and cases where there is an error of a few degrees but the angle is essentially considered to be ±60 degrees.

[0024] The elastic member 2 is longer than the electric component mounting board 1 in the optical axis direction. Therefore, if the elastic member 2 is arranged in the area where it overlaps with the flexible substrate 6 as viewed from the optical axis direction and in the area adjacent to this area, the flexible substrate 6 may be broken or the assembly workability may be deteriorated. Therefore, in this embodiment, the elastic member 2 cannot be arranged within the arrangement-prohibited angle range 16 of the electric component mounting board 1 shown in FIG. 7. The arrangement-prohibited angle range 16 includes the area where the small diameter portion 13 and the flexible substrate 6 overlap as viewed from the optical axis direction and the area adjacent to this area, and is an angle range of approximately 140 degrees. Note that approximately 140 degrees includes cases where it is actually 140 degrees, although there is a difference of several degrees between the case where it is strictly 140 degrees. It is desirable that the electric component mounting board 1 is held and fixed at three points that are approximately equal in distance to 120 degrees. However, in this embodiment, since the elastic member 2 cannot be arranged within the arrangement-prohibited angle range 16, the electric component mounting board 1 cannot be held by the three elastic members 2, and it is difficult to stably hold the electric component mounting board 1. If the three elastic members 2 were arranged within an angle range of approximately 220 degrees outside the arrangement-prohibited angle range 16, the arrangement would be uneven. Even if it were possible to arrange the elastic members 2 at both ends of the arrangement-prohibited angle range 16, the angle range in which the elastic members 2 cannot be held would be as much as 140 degrees, and the electric component mounting board 1 would rotate and vibrate around the straight line connecting the elastic members 2 at both ends. As a result, the electric component mounting board 1 would vibrate due to external vibrations, and the image stabilization performance would deteriorate.

[0025] Furthermore, since the contact terminal block 5 and the connector 14 are general-purpose components and their sizes are basically constant, if one attempts to miniaturize the electric component mounting board 1 in order to miniaturize the lens barrel 100, the unsuitable angular range 16 becomes larger. The larger the unsuitable angular range 16 becomes, the less stable the electric component mounting board 1 can be held, and the less able it becomes to suppress external vibrations.

[0026] Therefore, in this embodiment, an elastic member (second elastic member) 7 is disposed between the fixed barrel 3 and the electric component mounting board 1 in the optical axis direction. The elastic member 7 is disposed within the angle range 17, is made of an elastic material such as silicone rubber, and is a component integrally formed with a cylindrical shape 71 and a spherical shape 72. The elastic member 7 is positioned and fixed by inserting the cylindrical shape 71 into the recess 32 of the fixed barrel 3. The spherical shape 72 protrudes from the fixed barrel 3 in the optical axis direction. The surface of the electric component mounting board 1 on the side of the fixed barrel 3 contacts the tip of the spherical shape 72.

[0027] Since the flexible substrate 6 is made of a flexible material such as polyimide, a force F (reaction force or restoring force) that tries to open the folded-back portion 61 shown in Fig. 3 acts on the flexible substrate 6. The force F acts toward the fixed barrel 3 side (object side) in the optical axis direction as shown by the arrow in Fig. 3.

[0028] The electric component mounting board 1 is biased against the elastic member 7 by the force F and pressed against the tip of the spherical shape 72. Since the elastic member 7 is made of a material that is elastically deformable and has surface friction, such as silicone rubber, the electric component mounting board 1 and the spherical shape 72 come into contact with each other with an increased contact area, and a predetermined frictional force is applied. As a result, the elastic member 7 functions as a member that holds the third electric component mounting board 1. In other words, the electric component mounting board 1 is supported at three points by the two elastic members 2 and the elastic member 7, and is stably held. Therefore, it is possible to suppress the transmission of external vibrations to the shake detection means.

[0029] In this embodiment, flexible substrate 6 supplies power to drive components inside lens barrel 100 (for example, a zoom lens, a focus lens, a motion compensation lens, or an aperture unit). For this reason, flexible substrate 6 is provided with multiple patterns, each having a width of, for example, 0.3 mm or more. When multiple patterns with a large width are provided, force F becomes large and electric component mounting board 1 can be sufficiently biased.

[0030] The folded portion 61 will be described below with reference to FIG. 8. FIG. 8 is an explanatory diagram of the folded portion 61, showing a cross section of the folded portion 61 and its surrounding members. In FIG. 8(a), the folded portion 61 is formed between the contact terminal block 5 and the electric component mounting board 1. Therefore, the folded portion 61 overlaps with the contact terminal block 5 when viewed from the optical axis direction. In FIG. 8(b), the folded portion 61 is formed between the mount 4 and the electric component mounting board 1. Therefore, the folded portion 61 overlaps with the mount 4 when viewed from the optical axis direction, but does not overlap with the contact terminal block 5. In FIG. 8(c), the folded portion 61 overlaps with the mount 4 when viewed from the optical axis direction, but does not overlap with the electric component mounting board 1. In any of the cases of FIG. 8(a) to FIG. 8(c), the electric component mounting board 1 is urged toward the fixed barrel 3 by the force F from the folded portion 61. Therefore, flexible board 6 only needs to be connected to electric component mounting board 1 and contact terminal block 5 in a state in which folded-back portion 61 capable of biasing electric component mounting board 1 toward fixed cylinder 3 is formed.

[0031] In this embodiment, the flexible substrate 6 is connected to the electric component mounting substrate 1 on the surface opposite to the surface of the electric component mounting substrate 1 facing the fixed cylinder 3 (the surface facing the mount 4 and the contact terminal block 5), but the present invention is not limited to this. The flexible substrate 6 may be connected to the electric component mounting substrate 1 on the surface of the electric component mounting substrate 1 facing the fixed cylinder 3, as shown in Fig. 8(d).

[0032] As described above, the configuration of this embodiment can provide a lens barrel 100 that is space efficient and capable of suppressing the transmission of vibrations to the shake detection means.

[0033] In the following description, application examples and modifications of this embodiment, as well as optimal examples for obtaining better effects, will be described.

[0034] In this embodiment, the connector 14 and the two elastic members 2 are arranged at intervals of approximately 120 degrees around the optical axis, but the present invention is not limited to this. The elastic members 2 may be arranged within an angle range of approximately 240 degrees (second angle range) outside the angle range 17. Note that approximately 240 degrees includes cases where it is exactly 240 degrees and cases where there is an error of several degrees but is substantially considered to be 240 degrees.

[0035] In this embodiment, the positions (phase) of the connector 14 and the folded portion 61 around the optical axis are aligned so that the effect of the folded portion 61 of the flexible substrate 6 biasing the electric component mounting board 1 is maximized, but the present invention is not limited to this. As long as the electric component mounting board 1 can be biased toward the fixed barrel 3, the positions (phase) of the connector 14 and the folded portion 61 around the optical axis do not need to be aligned.

[0036] In this embodiment, the elastic member 7 is disposed in the unsuitable angular range 16 so as to overlap with the flexible substrate 6 when viewed from the optical axis direction. Center of is the position (phase) around the optical axis of the folded part 61 center (When viewed from the optical axis direction, the folded part 61 Center of It is desirable that the

[0037] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various combinations, modifications, and alterations are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0038] 1 Electrical component mounting board (first board) 2 Elastic member (first elastic member) 3 Fixed tube 4. Mount 5 Contact terminal block (electrical contacts) 6 Flexible board (second board) 7 Elastic member (second elastic member)

Claims

1. A fixed cylinder; a mount attached to the fixed barrel; an electrical contact secured to the mount; a first substrate disposed between the fixed cylinder and the mount; a second substrate connected to the first substrate and the electrical contacts with a folded portion formed therein, and disposed so as to overlap the first substrate when viewed along the optical axis; a plurality of first elastic members that are held by the fixed cylinder and that position and hold the first substrate in a direction perpendicular to the optical axis; a second elastic member that is held by the fixed cylinder and disposed between the fixed cylinder and the first substrate; A shake detection means for detecting shake is mounted on the first substrate, The lens barrel, wherein the first substrate is biased toward the fixed tube in the optical axis direction by a force from the folded portion, and contacts the second elastic member on the surface facing the fixed tube.

2. The lens barrel according to claim 1 , wherein the second substrate is connected to the first substrate on a surface of the first substrate opposite to a surface of the first substrate on the fixed barrel side.

3. The lens barrel according to claim 1 , wherein the second substrate is connected to the first substrate on a surface facing the fixed tube.

4. 4. The lens barrel according to claim 1, wherein a gyro sensor or an acceleration sensor is mounted on the first substrate.

5. 5. The lens barrel according to claim 1, wherein the second substrate overlaps with the second elastic member when viewed along the optical axis.

6. 6. The lens barrel according to claim 1, wherein the folded portion overlaps with the mount or the electrical contact when viewed along the optical axis.

7. 7. The lens barrel according to claim 1, wherein the second elastic member is disposed within a first angular range of ±60 degrees with respect to a straight line connecting the center of the connection portion between the first substrate and the second substrate and the center of the optical axis.

8. 8. The lens barrel according to claim 1, wherein a straight line connecting the center of the folded portion and a center of the optical axis is within a first angle range of ±60 degrees with respect to a straight line connecting the center of the connection portion between the first substrate and the second substrate and the center of the optical axis.

9. 9. The lens barrel according to claim 7, wherein the plurality of first elastic members are arranged within a second angular range of 240 degrees outside the first angular range.

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