JP6977856B2 - Aperture adjustment device, lens barrel and optical equipment - Google Patents

Description

The present invention relates to an aperture amount adjusting device, a lens barrel and an optical device.

An aperture device as an aperture amount adjusting device is used in an optical device such as a camera (see, for example, Patent Document 1).
With the conventional drawing device, a desired opening shape may not be obtained due to the influence of manufacturing error of each part, backlash required for operation, and the like.

Japanese Unexamined Patent Publication No. 2006-33747

In one embodiment of the present invention, a first opening member having a first opening and a first cam groove and a second opening member having a second opening and a hole are arranged so that at least a part thereof overlaps with each other. It has a first shaft that engages with the first cam groove and a second shaft that engages with the hole, and the first shaft moves along the first cam groove to face the first opening. The plurality of diaphragm blades include at least a first diaphragm blade and a second diaphragm blade that at least partially faces the first diaphragm blade. The first diaphragm blade is an opening amount adjusting device including the first shaft and the second shaft, and the second diaphragm blade is provided with a second cam groove that engages with the second shaft.
Further, one embodiment of the present invention is a lens barrel provided with the aperture amount adjusting device.
Further, one embodiment of the present invention is an optical device including the above-mentioned aperture amount adjusting device.

It is a schematic diagram of the lens barrel 200 provided with the aperture device 100 of the first embodiment, and the camera 300 equipped with the lens barrel 200. It is a perspective view of the state which assembled the diaphragm apparatus 100 of 1st Embodiment. It is an exploded perspective view of the diaphragm device 100. It is a figure explaining the structure of the diaphragm blade 30. It is a figure explaining the open / closed state of a diaphragm blade 30. It is a figure explaining the structure of the diaphragm blade 130 in 2nd Embodiment. It is a figure explaining the opening and closing state of the diaphragm blade 230 in the 1st modification. It is a figure explaining the opening and closing state of the diaphragm blade 330 in the 2nd modification.

(First Embodiment)
FIG. 1 is a schematic view of a lens barrel 200 provided with the aperture device 100 of the first embodiment and a camera 300 equipped with the lens barrel 200. FIG. 2 is a perspective view of the state in which the diaphragm device 100 of the first embodiment is assembled. FIG. 3 is an exploded perspective view of the diaphragm device 100 of the first embodiment.
An XYZ cross-coordinate system was provided on each surface including FIG. 1 as needed. In this coordinate system, in the camera position when the photographer shoots a horizontally long image with the optical axis L1 horizontal, the left-right (horizontal) direction is the X direction and the vertical (vertical) direction is the Y direction when viewed from the photographer. , The front-back (optical axis L1) direction is the Z direction (the arrows in the figure indicate the plus direction of each coordinate axis).

As shown in FIG. 1, the lens barrel 200 includes a lens 201 and a diaphragm device (aperture amount adjusting device) 100 for adjusting the diaphragm diameter of the lens 201. The opening 33 of the aperture device 100 is controlled by the control unit 70 (described later) so that the aperture diameter corresponds to the set aperture value. The lens barrel 200 is configured to be removable from the camera 300. Further, the camera 300 includes a camera body 301 and an image pickup unit 302 that converts an optical image of a subject into an electric signal. The camera 300 of the present embodiment is a digital single-lens reflex camera with interchangeable lenses.

As shown in FIGS. 2 and 3, the drawing device 100 includes a press plate 10, a rotating member (second opening member) 20, a plurality of drawing blades 30, and a cam member (first opening member) 40. I have. Of these, the press plate 10, the rotating member 20, and the cam member 40 are sequentially arranged in the Z-minus direction along the optical axis L1.

The press plate 10 is an annular member, and an opening 11 is formed in the center thereof. A stepping motor 50 is attached to the Z plus side of the press plate 10. The rotating shaft of the stepping motor 50 includes a pinion gear 51. The pinion gear 51 penetrates the hole 12 provided in the press plate 10 and protrudes to the Z-minus side in the state where the drawing device 100 is assembled.

A photo interrupter (hereinafter, also referred to as “PI”) 60 is attached to the Z plus side of the press plate 10. In the press plate 10, a light-shielding plate slit 13 is provided at a position where the PI 60 is attached. The light-shielding slit 13 is a groove for allowing the light-shielding plate 23 (described later) extending from the rotating member 20 to pass between the detection portions (not shown) of the PI 60. The stepping motor 50 and PI 60 are connected to the control unit 70 shown in FIG. 1 via an FPC (not shown). A signal is transmitted and received between the stepping motor 50 and PI 60 and the control unit 70. Further, electric power is supplied to the stepping motor 50 and PI 60 from the control unit 70.

The press plate 10 is provided with a tension measuring slit 14. The tension measuring slit 14 is a groove into which a protrusion 24 provided on the rotating member 20 is inserted. The tension applied to the protrusion 24 inserted into the tension measuring slit 14 is measured by a tension gauge (not shown) provided on the Z plus side of the press plate 10. Further, notches 15 are provided at a plurality of places on the outer edge of the press plate 10.

The rotating member 20 is an annular member, and is provided with a cylindrical portion (second opening) 21 fitted to the opening 11 in the center. The outer diameter of the rotating member 20 is smaller than that of the press plate 10 and the cam member 40. A segment gear 25 is provided on the outer edge of the rotating member 20. The segment gear 25 meshes with the pinion gear 51 attached to the rotating shaft of the stepping motor 50 in a state where the throttle device 100 is assembled.

When the stepping motor 50 is pulse-driven by the control unit 70, the segment gear 25 that meshes with the pinion gear 51 rotates. As the segment gear 25 rotates, the rotating member 20 rotates relative to the press plate 10 and the cam member 40 (described later) about the optical axis L1.
On the inner diameter side of the rotating member 20, a part of the above-mentioned cylindrical portion 21 projects toward the press plate 10 side (Z plus side). The outer diameter of the cylindrical portion 21 is substantially the same as the inner diameter of the opening 11 of the press plate 10. In the assembled state of the drawing device 100, the cylindrical portion 21 is rotatably fitted into the opening 11 of the press plate 10.

On the outer peripheral side of the rotating member 20, a light-shielding plate 23 and a protrusion 24 extending toward the press plate 10 side (Z plus side) are provided. When the light-shielding plate 23 moves in the light-shielding plate slit 13 and passes between the detection portions of the PI60 as the rotating member 20 rotates with respect to the press plate 10, the diaphragm is in a substantially open position due to a detection circuit (not shown). Detected. Protruding portions 26 protruding outward are provided at three locations on the outer peripheral side of the rotating member 20. A spherical protrusion 26a is provided on the cam member side (Z minus side) surface of the protrusion 26.
Further, the rotating member 20 is provided with holes 22 into which the support portions 31 of the diaphragm blades 30 (described later) are inserted at equal intervals along the circumferential direction. The holes 22 are provided at nine locations according to the number of diaphragm blades 30.

The diaphragm blade 30 is a member that forms a substantially circular opening facing the optical path opening 42 of the cam member 40 (described later). The diaphragm blade 30 is formed of a thin plate-shaped member. The diaphragm device 100 of the first embodiment includes nine diaphragm blades 30 (only one is shown in FIG. 3). As will be described later, the nine diaphragm blades 30 are arranged in an arc shape so that at least a part thereof overlaps with each other. Each diaphragm blade 30 includes a support portion (second shaft) 31, a cam follower (first shaft) 32, and an auxiliary cam groove (second cam groove) 34. The detailed configuration of the diaphragm blade 30 will be described later.

The cam member 40 is an annular member, and an optical path opening (first opening) 42 having the same diameter as the maximum diaphragm is formed in the center. The maximum diaphragm means a state in which the opening formed by the diaphragm blades 30 is the largest. The cam member 40 includes a main cam groove (first cam groove) 41 into which the cam follower 32 of the diaphragm blade 30 is inserted. The main cam groove 41 is a cam groove that guides the cam follower 32 along the groove shape. When the cam follower 32 moves along the main cam groove 41, the curved portion 35 (the portion forming the opening 33) of the diaphragm blade 30 moves toward or away from the optical axis L1 with the support portion 31 as the center. The main cam grooves 41 are formed at nine locations along the circumference of the cam member 40.

A circumferential wall 45 is formed on the press plate side (Z plus side) on a part of the outer periphery of the cam member 40. Further, a plurality of protrusions 43 extending from the circumferential wall 45 to the press plate side (Z plus side) are provided. The protrusion 43 is fitted with the notch 15 of the press plate 10 in a state where the drawing device 100 is assembled.

The cam member 40 has a facing surface 44 at a position facing the diaphragm blade 30. In the assembled state of the drawing device 100, the facing surface 44 comes into contact with the spherical protrusion 26a of the rotating member 20. The spherical protrusion 26a of the rotating member 20 comes into contact with the facing surface 44 of the cam member 40, so that the rotating member 20 is positioned in the optical axis direction. Further, when the rotating member 20 rotates, the spherical protrusion 26a slides on the facing surface 44. Therefore, the rotating member 20 can rotate while maintaining the position in the optical axis direction.

Next, the configuration of the diaphragm blade 30 will be described.
FIG. 4 is a diagram illustrating the configuration of the diaphragm blade 30. FIG. 4A is a diagram illustrating a partial configuration of the three diaphragm blades 30 and the cam member 40 arranged on the Y plus side. FIG. 4B is a diagram illustrating a gap between the auxiliary cam groove 34 and the support portion 31 and a gap between the main cam groove 41 and the cam follower 32. In FIG. 4A, the three diaphragm blades 30 are illustrated as a diaphragm blade 30a, a diaphragm blade 30b, and a diaphragm blade 30c.
FIG. 5 is a diagram illustrating an open / closed state of the diaphragm blade 30. FIG. 5A is a diagram illustrating a state in which the diaphragm blade 30 is set to the maximum diaphragm. FIG. 5B is a diagram illustrating a state in which the diaphragm blade 30 is set to the minimum diaphragm. In addition, in FIG. 5, a reference numeral is given only to a part of the members (the same applies to FIGS. 7 and 8 described later).

As shown in FIG. 4A, the diaphragm blades 30a to 30c are arranged so that at least a part thereof overlaps with each other. On the Z-minus side of the diaphragm blade 30a, the diaphragm blade 30b is arranged so as to overlap with a part of the diaphragm blade 30a. On the Z-minus side of the diaphragm blade 30b, the diaphragm blade 30c is arranged so as to overlap with a part of the diaphragm blade 30b. Adjacent diaphragm blades 30 (not shown) are arranged on the Z-minus side of the diaphragm blades 30c so as to overlap each other with a part of the diaphragm blades 30c. That is, if any of the nine diaphragm blades 30 is the diaphragm blade 30b, the diaphragm blades 30b overlap with a part of the adjacent diaphragm blades 30a on the Z plus side, and on the Z minus side, the diaphragm blades 30b overlap each other. It overlaps with a part of the adjacent diaphragm blades 30c. As described above, the nine diaphragm blades 30 are arranged in an arc shape on the Z plus side and the Z minus side so as to overlap each other with a part of the adjacent diaphragm blades 30.

Hereinafter, the configuration of each diaphragm blade 30 will be described by taking the diaphragm blade 30b as an example. Each diaphragm blade 30 is configured in the same manner as the diaphragm blade 30b.
In the diaphragm blade 30b, the end portion on the Z plus side of the support portion 31 is inserted into the hole 22 of the rotating member 20 (see FIG. 3). That is, the support portion 31 is held by the rotating member 20, and moves relative to the cam member 40 as the rotating member 20 rotates relative to the cam member 40. Specifically, the support portion 31 moves on the same circumference centered on the optical axis L1. Further, as shown in FIG. 4A, the support portion 31 is inserted into the auxiliary cam groove 34 of the adjacent diaphragm blades 30a. The auxiliary cam groove 34 is a cam groove that regulates the moving range of the diaphragm blade 30b when the support portion 31 moves relative to the cam member 40. In the present embodiment, the auxiliary cam groove 34 is formed so that the groove becomes an elongated hole substantially along the optical axis L1 direction. The operation of the auxiliary cam groove 34 will be described later.

As shown in FIG. 4B, the gap s1 between the auxiliary cam groove 34 and the support portion 31 is set to be larger than the gap s2 between the main cam groove 41 and the cam follower 32. This is to suppress excessive restraint of the support portion 31 moving in the auxiliary cam groove 34 rather than the cam follower 32 moving in the main cam groove 41. In FIG. 4B, the gaps s1 and s2 are shown in a state where they are moved to one side for easy comparison, but the gaps s1 and s2 are divided into both sides of the support portion 31 and the cam follower 32. It may be formed (the same applies to FIG. 6 (b) described later).

Further, in the diaphragm blade 30b, the cam follower 32 is inserted into the main cam groove 41 of the cam member 40 (see FIGS. 3 and 4). In the diaphragm blade 30b, when the support portion 31 moves (clockwise or counterclockwise) relative to the cam member 40 about the optical axis L1, the cam follower 32 moves along the main cam groove 41 of the cam member 40. Moving. As a result, the curved portion 35 of the diaphragm blade 30b moves in the direction toward the optical axis L1 or in the direction away from the optical axis L1 with the support portion 31 as the center.

FIG. 4A shows a state in which the diaphragm blade 30 has moved to the position where the diaphragm blade 30 becomes the minimum diaphragm. From this state, when the support portion 31 moves clockwise relative to the cam member 40 about the optical axis L1, the cam follower 32 of the diaphragm blade 30b moves along the main cam groove 41 on the outer peripheral side of the cam member 40. Move diagonally towards. Therefore, the curved portion 35 of the diaphragm blade 30b moves in a direction away from the optical axis L1 with the support portion 31 as the center. Then, when the support portion 31 moves to a position corresponding to the maximum diaphragm with the optical axis L1 as the center, the opening 33 formed by the nine diaphragm blades 30 becomes the largest, as shown in FIG. 5A.

Further, when the rotating member 20 (see FIG. 3) rotates counterclockwise about the optical axis L1 in a state where the curved portion 35 of each diaphragm blade 30 has moved to the position shown in FIG. 5 (a), the diaphragm blades The cam follower 32 of 30b moves diagonally along the main cam groove 41 toward the optical path opening 42 side of the cam member 40. Therefore, the curved portion 35 of each diaphragm blade 30 moves in the direction approaching the optical axis L1 with the support portion 31 as the center. Then, when the support portion 31 moves to a position corresponding to the minimum diaphragm with the optical axis L1 as the center, the opening 33 formed by the nine diaphragm blades 30 becomes the smallest, as shown in FIG. 5 (b).

The rotation direction and rotation amount of the rotating member 20 are controlled by a pulse signal supplied from the control unit 70 (see FIG. 1) to the stepping motor 50. By controlling the number of pulses of the pulse signal supplied from the control unit 70 to the stepping motor 50, the opening 33 formed by the nine diaphragm blades 30 can be adjusted to a desired size.

Further, as described above, the support portion 31 of the other adjacent diaphragm blades 30 is inserted into the auxiliary cam groove 34 of each diaphragm blade 30 (for example, the auxiliary cam groove 34 of the diaphragm blade 30b is adjacent to the support portion 31). The support portion 31 of the diaphragm blade 30c is inserted). Therefore, in the diaphragm blade 30, when the support portion 31 moves relative to the cam member 40 (clockwise or counterclockwise) with the optical axis L1 as the center, the cam follower 32 is relative to the main cam groove 41. In addition to the movement, the auxiliary cam groove 34 moves relative to the support portion 31. At that time, since the movement of the curved portion 35 of the diaphragm blade 30 is restricted by the support portion 31 inserted in the auxiliary cam groove 34, the light exceeds the amount of movement when the cam follower 32 moves along the main cam groove 41. It does not move in the direction of the axis L1. Such movement restrictions are imposed in each of the nine diaphragm blades 30 when the curved portion 35 of the diaphragm blade 30 moves away from the optical axis L1 with the support portion 31 as the center and in the direction approaching the optical axis L1. It works in any case of movement.

As described above, the diaphragm device 100 of the present embodiment is configured such that each of the nine diaphragm blades 30 restricts the movement of the other diaphragm blades 30 adjacent to each other. According to this, even if there is a manufacturing error of each component (cam groove, hole, etc.) constituting the diaphragm device 100, play required for operation, etc., the curved portion 35 of the specific diaphragm blade 30 is the other diaphragm blade. It is possible to suppress problems such as protruding from the curved portion 35 of 30 in the optical axis L1 direction or retracting from the optical axis L1 direction. Therefore, the lens barrel 200 provided with the aperture device 100 and the aperture device 100 of the present embodiment can obtain a desired aperture shape at any aperture value.

Further, in the diaphragm device 100 of the present embodiment, the aperture 33 formed by the nine diaphragm blades 30 can be adjusted to the diaphragm diameter according to the diaphragm value. Therefore, the camera 300 (see FIG. 1) provided with the lens barrel 200 can take an image with a more accurate exposure in the image pickup unit 302.
Further, in the diaphragm device 100 of the present embodiment, the support portion 31 not only has a function of moving relative to the cam member 40 to move the curved portion 35 of the diaphragm blade 30, but also the curved portion 35 of the diaphragm blade 30. However, it has a function of restricting the movement of the cam follower 32 in the direction of the optical axis L1 more than the amount of movement when the cam follower 32 moves along the main cam groove 41. Therefore, the diaphragm device 100 of the present embodiment can obtain a desired opening shape without increasing the number of parts.

Further, as shown in FIG. 4B, in the throttle device 100 of the present embodiment, the gap s1 between the auxiliary cam groove 34 and the support portion 31 is larger than the gap s2 between the main cam groove 41 and the cam follower 32. Is set to. According to this, since excessive restraint of the support portion 31 moving in the auxiliary cam groove 34 is suppressed as compared with the cam follower 32 moving in the main cam groove 41, each diaphragm blade 30 can be operated more smoothly. can.

(Second Embodiment)
Next, the diaphragm device 100A of the second embodiment will be described.
The diaphragm device 100A of the second embodiment has a different diaphragm blade configuration from the first embodiment. The other overall configurations of the present embodiment are the same as those of the first embodiment, and the same components as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. Further, the illustration of the overall configuration of the diaphragm device 100A is also omitted.

FIG. 6 is a diagram illustrating the configuration of the diaphragm blade 130 in the second embodiment. FIG. 6A is a diagram illustrating a partial configuration of the three diaphragm blades 130 and the cam member 40 arranged on the Y plus side. FIG. 6B is a diagram illustrating a gap between the auxiliary cam groove 34 and the regulating portion 36 and a gap between the main cam groove 41 and the cam follower 32.
In FIG. 6A, the three diaphragm blades 130 are illustrated as the diaphragm blades 130a, the diaphragm blades 130b, and the diaphragm blades 130c. Further, although not shown, the diaphragm device 100A of the second embodiment also includes nine diaphragm blades 130 like the diaphragm device 100 of the first embodiment, and is a circle so that at least a part thereof overlaps with each other. They are arranged in an arc.

Hereinafter, the configuration of each diaphragm blade 130 will be described by taking the diaphragm blade 130b as an example. As shown in FIG. 6A, the diaphragm blade 130b includes a support portion 31, a cam follower 32, an auxiliary cam groove 34, and a regulation portion 36 (third axis). Of these, the configurations of the support portion 31 and the cam follower 32 are the same as those in the first embodiment, and thus the description thereof will be omitted. In the second embodiment, the support portion 31 is arranged at a position that does not interfere with the adjacent diaphragm blades 130.
The diaphragm blade 130b is different from the first embodiment in that the regulating portion 36 provided in the adjacent diaphragm blade 130c is inserted into the auxiliary cam groove 34. In the present embodiment, the support portion 31 (the end on the Z plus side) of the diaphragm blade 130b is inserted into the hole 22 of the rotating member 20, and is not inserted into the auxiliary cam groove 34 of the adjacent diaphragm blade 130a. ..

In the diaphragm blade 130b, the position of the auxiliary cam groove 34 is provided at a position that does not interfere with the support portion 31 of the adjacent diaphragm blade 130c, unlike the first embodiment. Also in this embodiment, the auxiliary cam groove 34 is formed so that the groove is an elongated hole substantially along the optical axis L1 direction.
Further, the diaphragm blade 130b is provided with a regulating portion 36 on the Z plus side. The regulating portion 36 is a shaft member for regulating the moving range of the diaphragm blade 130a when the supporting portion 31 moves relative to the cam member 40. As shown in FIG. 6B, the gap s1 between the auxiliary cam groove 34 and the regulating portion 36 is set to be larger than the gap s2 between the main cam groove 41 and the cam follower 32.

As described above, in the present embodiment, the restricting portion 36 of the other adjacent diaphragm blades 130 is inserted into the auxiliary cam groove 34 of each diaphragm blade 130 (for example, in the auxiliary cam groove 34 of the diaphragm blade 130b). Is inserted with the regulating portion 36 of the adjacent diaphragm blade 130c). Therefore, in the diaphragm blade 130, when the support portion 31 moves relative to the cam member 40 (clockwise or counterclockwise) with the optical axis L1 as the center, the cam follower 32 is relative to the main cam groove 41. The auxiliary cam groove 34 moves relative to the regulating portion 36 as well as moving in a targeted manner. At that time, the movement of the curved portion 35 of the diaphragm blade 30 is restricted by the regulating portion 36 inserted in the auxiliary cam groove 34. Therefore, the curved portion 35 of the diaphragm blade 30 does not move in the direction of the optical axis L1 more than the amount of movement when the cam follower 32 moves along the main cam groove 41. Such movement restrictions are imposed in each of the nine diaphragm blades 130 when the curved portion 35 of the diaphragm blade 130 moves away from the optical axis L1 with the support portion 31 as the center and in the direction approaching the optical axis L1. It works in any case of movement.

Therefore, the lens barrel 200 provided with the aperture device 100A and the aperture device 100A of the second embodiment can obtain a desired aperture shape at any aperture value, similarly to the aperture device 100 of the first embodiment. ..
Further, in the throttle device 100A of the present embodiment, the position where the auxiliary cam groove 34 is provided is not restricted to the position where the support portion 31 can be inserted, so that the degree of freedom in design can be improved.

(Deformed form)
Not limited to the embodiments described above, various modifications and changes as shown below are possible, and these are also within the scope of the present invention. In the following description, the first embodiment and the second embodiment are collectively referred to as "the present embodiment". Therefore, for example, the diaphragm device 100 may be the diaphragm device 100A.

(1) In the present embodiment, an example in which nine diaphragm blades 30 of the diaphragm device 100 are used has been described. Not limited to this, the number of diaphragm blades may be 8 or less, or 10 or more. Hereinafter, in the configuration of the first embodiment, an example in which the number of diaphragm blades is 5 and an example in which the number of diaphragm blades is 12 will be described.
FIG. 7 is a diagram illustrating an open / closed state of the diaphragm blade 230 in the first modified form. FIG. 7A is a diagram illustrating a state in which the diaphragm blade 230 is set to the maximum diaphragm. FIG. 7B is a diagram illustrating a state in which the diaphragm blade 230 is set to the minimum diaphragm.
The first modification is different from the first embodiment in that the diaphragm device 100B has five diaphragm blades 230. The other overall configurations in the present embodiment are the same as those in the first embodiment, and the same components as those in the first embodiment are designated by the same reference numerals except for the diaphragm blade 230, and the description thereof will be omitted. Further, the illustration of the overall configuration of the diaphragm device 100B is also omitted.

As shown in FIG. 7, in the diaphragm device 100B of the present modified form, the five diaphragm blades 230 are arranged in an arc shape so that at least a part thereof overlaps with each other. Each diaphragm blade 230 includes a support portion 31, a cam follower 32, and an auxiliary cam groove 34. In this modified form, the support portion 31 of each diaphragm blade 230 is inserted into the auxiliary cam groove 34 of the adjacent diaphragm blade 230.

When the rotating member 20 (see FIG. 3) rotates counterclockwise about the optical axis L1 in a state where the curved portion 35 of each diaphragm blade 230 is moved to the position shown in FIG. 7 (a), the diaphragm blade 230 The cam follower 32 moves diagonally toward the optical path opening 42 side along the main cam groove 41 (see FIG. 3). Therefore, the curved portion 35 of the diaphragm blade 230 moves in the direction approaching the optical axis L1 with the support portion 31 as the center. Then, when the support portion 31 moves to a position corresponding to the minimum diaphragm with the optical axis L1 as the center, the opening 33 formed by the five diaphragm blades 230 becomes the smallest, as shown in FIG. 7B.

Further, when the rotating member 20 rotates clockwise around the optical axis L1 in a state where the curved portion 35 of each diaphragm blade 230 has moved to the position where the minimum diaphragm is reached, the cam follower 32 of the diaphragm blade 230 becomes the main cam groove 41. Along the cam member 40, the cam member 40 moves diagonally toward the outer peripheral side. Therefore, the curved portion 35 of the diaphragm blade 230 moves in a direction away from the optical axis L1 with the support portion 31 as the center. Then, when the support portion 31 moves to a position corresponding to the maximum diaphragm with the optical axis L1 as the center, the opening 33 formed by the five diaphragm blades 230 becomes the largest, as shown in FIG. 7A.

FIG. 8 is a diagram illustrating an open / closed state of the diaphragm blade 330 in the second modified form. FIG. 8A is a diagram illustrating a state in which the diaphragm blade 330 is set to the maximum diaphragm. FIG. 8B is a diagram illustrating a state in which the diaphragm blade 330 is set to the minimum diaphragm.
The second modification is different from the first embodiment in that the diaphragm device 100C has 12 diaphragm blades 330. The other overall configurations in the present embodiment are the same as those in the first embodiment, and the same components as those in the first embodiment are designated by the same reference numerals except for the diaphragm blade 330, and the description thereof will be omitted. Further, the illustration of the overall configuration of the diaphragm device 100C is also omitted.

As shown in FIG. 8, in the diaphragm device 100C of the present modified form, the 12 diaphragm blades 330 are arranged in an arc shape so that at least a part thereof overlaps with each other. Each diaphragm blade 330 includes a support portion 31, a cam follower 32, and an auxiliary cam groove 34. In this modified form, the support portion 31 of each diaphragm blade 330 is inserted into the auxiliary cam groove 34 of the adjacent diaphragm blade 330.

When the rotating member 20 (see FIG. 3) rotates counterclockwise about the optical axis L1 in a state where the curved portion 35 of each diaphragm blade 330 is moved to the position shown in FIG. 8 (a), the diaphragm blade 330 Since the cam follower 32 moves along the main cam groove 41 (see FIG. 3), the curved portion 35 of the diaphragm blade 330 moves in a direction approaching the optical axis L1 with the support portion 31 as the center. Then, when the support portion 31 moves to a position corresponding to the minimum diaphragm with the optical axis L1 as the center, the opening 33 formed by the 12 diaphragm blades 330 becomes the smallest, as shown in FIG. 8 (b).

Further, when the rotating member 20 rotates clockwise around the optical axis L1 in a state where the curved portion 35 of each diaphragm blade 330 has moved to the position where the minimum diaphragm is reached, the cam follower 32 of the diaphragm blade 330 becomes the main cam groove 41. Along the cam member 40, the cam member 40 moves diagonally toward the outer peripheral side. Therefore, the curved portion 35 of the diaphragm blade 330 moves in a direction away from the optical axis L1 with the support portion 31 as the center. Then, when the support portion 31 moves to a position corresponding to the maximum diaphragm with the optical axis L1 as the center, the opening 33 formed by the 12 diaphragm blades 330 becomes the largest, as shown in FIG. 8A.

In each of the above-described deformation forms, when the auxiliary cam groove 34 moves relative to the support portion 31, the movement of the curved portion 35 of the diaphragm blade 230 (330) is caused by the support portion inserted into the auxiliary cam groove 34. It is regulated by 31. Therefore, the curved portion 35 of the diaphragm blade 230 (330) does not move in the direction of the optical axis L1 more than the amount of movement when the cam follower 32 moves along the main cam groove 41. Therefore, the aperture device 100B (100C) of each of the above-mentioned modifications and the lens barrel provided with these aperture devices can obtain a desired aperture shape at any aperture value, as in the first embodiment.

In the first and second modifications, the configuration in which the support portion 31 is inserted into the auxiliary cam groove 34 has been described as in the first embodiment, but the present invention is not limited to this. In the first and second modified embodiments, the configuration in which the regulating portion 36 is inserted into the auxiliary cam groove 34 may be applied as in the second embodiment.

(2) In the throttle device 100 of the present embodiment, an example in which the rotating member 20 rotates with respect to the cam member 40 has been described. Not limited to this, a member corresponding to the rotating member 20 may be fixed and the cam member 40 may rotate. In that case, for example, the main cam groove (41) is formed in the member corresponding to the rotating member 20, and the hole (22) is formed in the cam member 40 (the arrangement of the support portion 31 and the cam follower 32 in the diaphragm blade 30 is also opposite. do). That is, the rotating member 20 and the cam member 40 may be configured to be relatively rotatable with respect to each other.

(3) The configuration of the diaphragm device 100A of the second embodiment may be applied to the diaphragm device 100 of the first embodiment. For example, two auxiliary cam grooves 34 are provided in one diaphragm blade 30, and a support portion 31 of an adjacent diaphragm blade 30 is inserted into one auxiliary cam groove 34 corresponding to the first embodiment. In the other auxiliary cam groove 34 corresponding to the above, the restricting portion 36 provided in the adjacent diaphragm blade 30 may be inserted. Further, in a plurality of diaphragm blades 30 arranged in an arc shape, the configuration of the first embodiment and the configuration of the second embodiment may be alternately applied to every other diaphragm blade 30.

(4) In the present embodiment, the camera 300 provided with the lens barrel 200 has been described as a digital single-lens reflex camera with interchangeable lenses. Not limited to this, it can also be applied to mirrorless interchangeable-lens cameras, digital cameras with integrated lenses, video cameras, mobile terminals, and the like.
The embodiments and modifications can be used in combination as appropriate, but detailed description thereof will be omitted. Further, the present invention is not limited to the above embodiments.

20: Rotating member, 21: Cylindrical part, 30, 130, 230, 330: Aperture blade, 31: Support part, 32: Cam follower, 33: Aperture, 34: Auxiliary cam groove, 36: Regulatory part, 40: Cam member, 41: Main cam groove, 42: Optical path opening, 200: Lens barrel, 300: Camera

Claims (9)

A first opening member having a first opening and a first cam groove,
A second opening member having a second opening and a hole,
At least a part thereof is arranged so as to overlap each other, and has a first shaft that engages with the first cam groove and a second shaft that engages with the hole portion, and the first shaft is in the first cam groove. A plurality of diaphragm blades, which change the opening facing the first opening by moving along the same, are provided.
The plurality of diaphragm blades include at least a first diaphragm blade and a second diaphragm blade that at least partially faces the first diaphragm blade.
The first diaphragm blade is
With the first axis
With the second axis,
The second diaphragm blade is
A second cam groove that engages with the second shaft.
Aperture amount adjustment device. The opening amount adjusting device according to claim 1.
The second diaphragm blade is
With the first axis
The second axis is provided.
Aperture amount adjustment device. A first opening member having a first opening and a first cam groove,
A second opening member having a second opening and a hole,
At least a part thereof is arranged so as to overlap each other, and has a first shaft that engages with the first cam groove and a second shaft that engages with the hole portion, and the first shaft is in the first cam groove. It is provided with a plurality of diaphragm blades that change the opening facing the first opening by moving along the same.
The plurality of diaphragm blades include at least a first diaphragm blade and a second diaphragm blade that at least partially faces the first diaphragm blade.
The first diaphragm blade is
With the first axis
With the second axis
A third axis different from the first axis and the second axis is provided.
The second diaphragm blade is
A second cam groove that engages with the third shaft.
Aperture amount adjustment device. The opening amount adjusting device according to claim 3.
The third axis does not interfere with the second axis.
Aperture amount adjustment device. The opening amount adjusting device according to any one of claims 1 to 4.
The second cam groove is
It has a radial inclination different from that of the first cam groove.
Aperture amount adjustment device. The opening amount adjusting device according to any one of claims 1 to 5.
The gap between the second cam groove and the second shaft is larger than the gap between the first cam groove and the first shaft.
Aperture amount adjustment device. The opening amount adjusting device according to any one of claims 1 to 6.
The first axis moves along the first cam groove to change the opening formed by the plurality of diaphragm blades, and the second axis approaches or separates from the optical axis along the second cam groove. Move in the direction,
Aperture amount adjustment device. A lens barrel comprising the aperture amount adjusting device according to any one of claims 1 to 7. An optical device comprising the aperture amount adjusting device according to any one of claims 1 to 7.

Images